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Coronavirus Disease 2019 (COVID-19)

Frank J. Domino, MD, Robert Baldor, Kathleen Barry, MD, Jeremy Golding, MD and Mark B. Stephens, MD Reviewed 04/2021

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  • Coronavirus Disease 2019 (COVID-19) is a severe acute multi-system respiratory syndrome which was first detected in Wuhan City, Hubei Province, China.

  • The disease results from a novel virus, named coronavirus 2 (SARS-CoV-2).

  • The syndrome leads to multisystem complications including respiratory failure and death, particularly in elderly and immune-compromised individuals.




Pediatric cases of COVID-19 typically are milder than adults; however, a multisystem inflammatory syndrome (MIS-C) related to COVID-19, similar to Kawasaki disease (toxic shock syndrome), is reported in children. It is a "post-infectious immune response" associated with a positive test either for SARS-CoV-2 or for antibodies to the virus (1) (

  • Common findings in MIS-C include the need for respiratory support, cardiovascular and clotting problems as well as gastrointestinal symptoms and skin rashes. Children with MIS-C often require intensive care (2).



  • A novel (new) coronavirus (SARS-CoV-2) causes the coronavirus disease COVID-19.

  • SARS-CoV-2 is related to bat coronaviruses and to other Severe Acute Respiratory Syndrome (SARS) coronaviruses.

  • It is believed to evolve in animals including camels, cats, and bats.

  • Virology: SARS-CoV-2 is a positive-sense single stranded RNA virus (+ssRNA), a beta-coronavirus belonging to the same subgenus as the virus responsible for the severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS). The SARS-CoV-2 virus uses the angiotensin-converting enzyme 2 (ACE-2) receptor for cellular entry.

    • Variants:

      • B1.1.7/N501Y: the WHO has said the variant has been found in Australia, Denmark, Iceland, Italy, and the Netherlnds and it is assumed to be in the U.S. While more virulent (spreads more readily), it has not yet been found to cause more severe disease than other variants. The U.K. does more viral surveillance than other countries (3).

      • B1.251: South Africa may be resistant to the Astra Zeneca vaccine to prevent mild illness, which led the government to stop its use until further data is reviewed.

      • P.1 emerged, first identified in travelers from Brazil who were tested during routine screening at an airport in Japan. This variant contains additional mutations that may affect its ability to be recognized by antibodies.

  • For over 95% of infected persons, symptoms appear within 11.5 days. Median incubation time to is about was 5.5 days (4).

  • Symptoms develop because of viral effects on pulmonary tissue, and the associated immune response.

  • Coagulopathy: The virus affects the pulmonary and systemic vasculature, resulting in venous and arterial thrombosis including stroke, pulmonary embolism, and myocardial infarction, even in younger patients not normally considered to be at high risk for these problems.

  • A retrospective analysis of patients in New York City emergency departments who underwent computed tomography pulmonary angiography (CTPA) between April 1 and May 1, 2020 found 18.8% of CTPA studies were positive for PE compared to 7.6% during the same time period in 2019 (5).

  • Venous thromboembolism (VTE) was radiologically confirmed in, on average, 4.8% of patients, ranging from 7.6% in those critically ill and 3.1% in non–critically ill patients. The rate of arterial thromboembolism was 2.8% overall, with 5.6% in critically ill patients and 1.2% in non–critically ill patients. Bleeding was found in 4.8% of patients, ranging from 7.6% in critically ill patients to 3.1% in non–critically ill patients; the rate of major bleeding was 2.3% overall, but as high as 5.6% in critically ill patients.

  • Thrombosis was predicted by increased by D-dimer level at admission (>2500 ng/mL; odds ratio, 6.79), elevated platelet count, C-reactive protein, and erythrocyte sedimentation rate.

  • Bleeding was predicted by elevated D-dimer level at admission (>2500 ng/mL; OR, 3.56) and by excess thrombocytopenia (6).


  • Travel from countries of the world or specific regions that are experiencing outbreaks

  • The U.S. State Department issues travel bans and/or advisories as conditions change around the world, and advice can be found at

  • Spread primarily via respiratory droplets produced when an infected person coughs or sneezes

  • Risk factors for severe COVID infection include age over 65 or older, chronic kidney chronic obstructive pulmonary disease, obesity (BMI ≥ 30, risk of death: (OR = 1.71; 95% CI, 0.8-3.64) for BMI ≥ 35, risk of death: OR of 12.1 (95% CI, 3.25-45.1) (7), serious heart conditions (e.g. heart failure, coronary artery disease, cardiomyopathies), sickle cell disease, type 2 diabetes, and being immunocompromised after a solid organ transplant. The more of these conditions people have, the higher their risk. For pediatric patients, the CDC states: "Children who are medically complex, who have neurologic, genetic, metabolic conditions, or who have congenital heart disease are at higher risk for severe illness from COVID-19 than other children" (8).

  • Clinical risk factors for severe disease include chest radiography abnormality, age, hemoptysis, dyspnea, unconsciousness, number of comorbidities, cancer history, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, and direct bilirubin; these can be evaluated using a web-based risk calculator (9).

  • Proton pump inhibitor (PPI)

    • An October 2020 meta-analysis of high-quality studies on 37,000+ patients found an increased risk of severe or fatal course of COVID-19 with use of PPIs compared to nonuse of PPIs (pooled OR = 1.46; 95% CI 1.34–1.60) (10).

    • A November, 2020 meta-analysis reviewed data on 145,000+ patients and found PPIs associated with a non-significant increase in COVID-19 infection risk, but did not find current or regular PPI users were more likely to have severe outcomes of COVID-19 than PPI non-users, with a pooled OR of 1.67 (95% CI 1.19 to 2.33, p=0.003) (11).

  • Vitamin D deficiency:

    • A retrospective cohort study of 489 COVID-19 patients found after multivariate analysis that testing positive for COVID-19 was associated with vitamin D deficiency (RR=1.77; 95% CI 1.12–2.81) compared to sufficient vitamin D levels (12).

    • Observational study of 235 Iranian COVID patients admitted to the hospital found in those over 40, 20% had insufficient vitamin D levels (<30 ng/mL) on admission and ~90% who died had insufficient levels (13).

    • A pilot trial of early 25-hydroxyvitamin D treatment in hospitalized COVID-19 patients reduced ICU admissions (2% in the treated group vs. 50% in placebo group) and 0% of the vitamin D group died, while in the placebo group, ~8% died (14).

    • Meta-analysis of over 500 patients found vitamin D supplementation lowered ICU requirements, but did not influence mortality (15).

  • Blood group A: an early study comparing the genomes of ~1600 people with severe COVID-19 in Italy and Spain with controls found blood group A was associated with a 45% increased risk for COVID-19 respiratory failure, while blood group O was associated with a 35% lower risk (16). A January 2021 cohort study found those with blood group A had higher rates of adverse cardiac events with COVID-19 than other groups (17). Further research is needed to discern the correlation of blood group and COVID outcomes.


Pregnancy increases risk of ICU admission (1.5%) vs. non-pregnant (0.9%), and risk for mechanical ventilation 0.5% vs. 0.3%. Mortality rates are not different (18).

  • Pregnancy and breastfeeding do not increase vertical transmission. Researchers compared data on ~80 neonates whose mothers were SARS-CoV-2 positive. About 80% of these children roomed with their mother. Mothers wore surgical masks when near their infant and used good hand and breast hygiene. At 14 days, none of the neonates tested positive (19). A systematic review of pregnancy-related SARS-CoV-2 infection found the risk of maternal intensive care unit admission was 3.0% (critical disease diagnosis [defined as respiratory failure, septic shock, and multiorgan dysfunction or failure] was 1.4%), with no deaths reported. Rate of preterm birth was 20.1% (~10%-11% in non-infected births worldwide); the cesarean section rate was 84.7% (almost triple the baseline rate in the three included countries). Vertical transmission did not occur; rates of neonatal death was found to be 0.3% (20).

  • A study of SARS-CoV-2 positive women who submitted breast milk samples evaluated by reverse transcriptase–polymerase chain reaction found no viral particles, implying breastfeeding when infected with the virus is not likely to transmit infection (21).


  • Population health:

    • The CDC, in December, 2020, designated 10 critical recommendations to address the SARS-CoV-2 pandemic: face mask use, physical distancing, avoidance of nonessential indoor spaces (e.g., restaurants) and crowded outdoor spaces, increased testing, diagnosis, and isolation, contact tracing, postponing travel, improved ventilation and effective vaccination (22).

    • Containment efforts (quarantine, universal testing, rapid identification of illness, contact tracing) are effective. When disease increases faster than containment can control (as in the U.S., Spain, Italy), mitigation strategies are initiated (hand hygiene, travel restrictions, school closures, and social distancing).

    • Physical distancing of at least 1 meter (preferably 2 meters) reduces viral transmission; use of face masks reduces the risk of infection as does proper use of eye protection (23).

  • Social distancing:

    • Keeping six feet apart from others, closing of schools, workplaces, meetings, social and religious gatherings, and sporting events

    • Minimizing contact with others and closure of nonessential business is effective at stopping the exponential spread of the virus (24).

    • "Close contact" was redefined as being within 6 feet of an infected person for at least 15 minutes over a 24-hour period beginning 2 days before symptom onset (or 2 days before testing in asymptomatic patients). Previously, the 15-minute exposure window was continuous (25).

    • Protection increases as distance is lengthened (change in relative risk [RR] 2·02 per m; pinteraction=0·041; moderate certainty).

    • Social distancing resulted in decreased rate of childhood infection disease (acute otitis media, bronchiolitis, common cold, croup, gastroenteritis, influenza, nonstreptococcal pharyngitis, pneumonia, sinusitis, skin and soft tissue infections, streptococcal pharyngitis, and urinary tract infection (UTI) based upon observational cohort study from a large pediatric primary care network in Massachusetts. Rates of influenza, croup, and bronchiolitis went to <1 case per 100,000 (26).

    • The U.S. CDC reports that in schools, 3 (three) feet of distancing is safe (27).

  • Face masks

    • The CDC updated their recommendations on masks, stating they prevent an infected person from spreading the infection AND effectively filter to prevent the mask wearer from contracting an infection (28).

    • Face masks do not increase CO2 retention. A study of 15 physicians without lung disease and 15 veterans with severe chronic obstructive pulmonary disease (COPD) found no significant changes in end-tidal CO2 or oxygen saturation at 5 and 30 minutes of mask wearing; during a 6-minute walk test, patients with COPD did not demonstrate CO2 retention while wearing a mask (29).

    • High-speed camera evaluation of respiratory droplets expelled during speaking, coughing, and sneezing suggests that a 3-layer surgical mask was the most effective at limiting droplet spread. A 2-layer cloth cotton mask was more effective during coughing and sneezing than one made from a single layer, but even a single-layer mask was better than no mask (30).

    • Theoretical data finds N95 masks most efficacious, followed by surgical masks, polypropylene masks and handmade cotton face coverings. Gaiter-type fleece coverings converted larger respiratory droplets into numerous smaller droplets which can travel further and were considered “counterproductive” (31). 

    • Increasing data shows aerosol transmission (with particles able to travel and infect in areas with recirculated air) is likely to occur (32).

    • February, 2021: The CDC, after completing two studies, determined that wearing a cloth mask over a medical procedure mask is the optimal masking method (33).

  • Face shields

    • Healthcare workers who added a face shield to a face mask reduced their personal infection rate almost 100% in an observational study from India (34).

  • Hand washing, avoid others if ill, avoid touching face

    • Hand washing for 20 seconds with soap lowers viral carriage and lowers risk of transmission.

  • Humidity: A summary of 10 international studies investigated the influence of humidity on viral (corona viruses SARS-CoV-1, MERS and SARS-CoV-2) spread and survival found air humidity >40% lowers the potential for the virus to be spread through aerosol transmission (35).

  • Social isolation and quarantine:

    • Self-quarantine recommended for all with symptoms of fever or new cough until symptoms resolve

    • Quarantine is recommended if exposed to confirmed COVID-19 infections to reduce infections and deaths.

    • Quarantine of returning international travelers from high risk countries to prevent transmission and death has small benefit.

    • Combination of quarantine and prevention methods (sheltering, school and business closures, social distancing) had a greater effect on disease transmission, use of critical care and deaths compared to quarantine alone.

  • Use of gloves is not recommended for the general population as it may decrease patient hand hygiene and increase carelessness.

  • Exposure to a contaminated surface "is not thought to be the main way the virus spreads" (36).

  • Exposure risk:

    • Children aged 10-19 years have been found to spread SARS-CoV-2 to household members more readily than adults. Data from South Korea of ~60,000 contacts of 5700 COVID-19 index patients. Overall, 12% of household contacts were infected, versus 2% of non-household contacts. When the index patient was aged 10–19 years, 19% of household contacts were infected; when the index patient was 30–49, 12% of household members were infected; and when the index patient was 0–9 years, 5% of household contacts were infected (37).

    • Household exposure to SARS-CoV-2 appears to be the most common risk factor for transmission based upon contact tracing, cell phone data and public transportation use. Ten percent of household contacts to index cases became infected vs. 1% from healthcare settings and 0.1% from public transportation. Risk for transmission increased as severity of index case symptoms increased (38).

  • School reopening: The CDC is updating K-12 school guidance to reflect the latest science on physical distance between students in classrooms. CDC now recommends that, with universal masking, students should help maintain a distance of at least 3 feet in classroom settings. CDC has updated its operational strategy to say:

    • In elementary schools, CDC recommends all students remain at least 3 feet apart in classrooms where mask use is universal — regardless of whether community transmission is low, moderate, substantial, or high.

    • In middle and high schools, CDC also recommends students should be at lease 3 feet apart in classrooms where mask use is universal and in communities where transmission is low, moderate, or substantial.

    • Middle school students and high school students should be at least 6 feet apart in communities where transmission is high, if cohorting is not possible. Cohorting is when groups of students are kept together with the same peers and staff throughout the school day to reduce the risk for spread throughout the school. This recommendation is because COVID-19 transmission dynamics are different in older students — that is, they are more likely to be exposted to SARS-CoV-2 and spread it than younger children (27).

  • American Academy of Pediatrics (AAP) released guidelines regarding children and COVID-19 which include cloth face masks being recommended for nearly all children aged ≥ 2 years and guidance on when to test children: having COVID-19 symptoms, having a close contact with a confirmed case, and prior to elective procedures (39).

  • Vaccine data:

    • As of February 8, 2021, the Pfizer/BioNTech and Moderna vaccines have been given Emergency Use Authorization by the U.S. Johnson & Johnson received EUA on February 27, 2021 (40).

    • Vaccines currently reporting successful outcomes:

      • Moderna: 2 doses, 4 weeks apart; approved for those aged 16 years and older. Their Phase 3 study included >7,000 Americans over the age of 65 and >5,000 Americans under 65 with high-risk chronic diseases (diabetes, severe obesity and cardiac disease). Reports find a 94.1% efficacy with a "100% efficacy at preventing severe illness."

      • The Pfizer and BioNTech SARS-CoV-2 vaccine: mRNA, 2 doses, 3 weeks apart; 18 years and older; has demonstrated an efficacy >90% at 7 days after teh second dose is given, based upon a phase 3 trial of ~44,000 volunteers (41). Pfizer reports a "95% efficacy." On December 10, 2020, the FDA Advisors recommended the Pfizer/BioNTech vaccine.

      • Johnson & Johnson: single dose, 18 years and older; vaccine 72% effective in the U.S. and 66% effective overall at preventing moderate to severe COVID-19, 28 days after vaccination; 66% effective in preventing moderate and severe disease, 85% effective overall at preventing hospitalization, and 100% at preventing death.

    • On March 3, 2021, the CDC issued the following guidelines concerning post-vaccination (at least 2 weeks following second dose of Pfizer or Moderna, or 2 weeks following Johnson & Johnson [Janssen] vaccine) status:

      • Fully vaccinated people can:

        • Visit with other fully vaccinated people indoors without wearing masks or physical distancing

        • Visit with unvaccinated people from a single household who are at low risk for severe COVID-19 disease indoors without wearing masks or physical distancing

        • Refrain from quarantine and testing following a known exposure if asymptomatic

      • For now, fully vaccinated people should continue to:

        • Take precautions in public like wearing a well-fitted mask and physical distancing

        • Wear masks, practice physical distancing, and adhere to other prevention measures when visiting with unvaccinated people who are at increased risk for severe COVID-19 disease or who have an unvaccinated household member who is at risk for severe COVID-19 disease

        • Wear masks, maintain physical distance, and practice other prevention measures when visiting with unvaccinated people from multiple households

        • Avoid medium- and large-sized in-person gatherings

        • Get tested if experiencing COVID-19 symptoms (42)

    • Not currently given Emergency Use Authorization:

      • University of Oxford and AstraZeneca vaccine; adenovirus-vector, 2 doses 4-12 weeks apart; 18 years and older. The vaccine has demonstrated between 62% and 90% efficacy; the better outcome was found with a low dose initial vaccine followed by a larger dose one month later with no significant adverse effects. Additionally, it does not require the extreme temperature transportation issues of the Moderna and Pfizer vaccines.  This can be stored and transported in normal refrigerated conditions (2-8 degrees Celsius, or 36-46 degrees Fahrenheit) for at least six months.

        • Recent data out of South Africa shows limited efficacy against the South African variant, leading the country to stop providing to its citizens. Data and updated trial outcomes pending.


Office-based triage 
  • Screen all patients prior to facility entry (

  • Establish Telemedicine protocol.

  • For those who come to the office:

    • Instruct patients to wear a surgical mask.

    • Maintain strict physical distancing.

    • Remind parents who wish to have a child seen not to bring other family members into the office, and only bring in one child.

  • In general, patients with COVID-19 can be grouped into the following illness categories:

    • Asymptomatic or presymptomatic infection: individuals who test positive for SARS-CoV-2 but have no symptoms

    • Mild illness: individuals who have any of various signs and symptoms (e.g. fever, cough, sore throat, malaise, headache, muscle pain) without shortness of breath, dyspnea, or abnormal imaging

    • Moderate illness: individuals who have evidence of lower respiratory disease by clinical assessment or imaging and a saturation of oxygen (SaO2) >93% on room air at sea level

    • Severe illness: individuals who have respiratory frequency >30 breaths per minute, SaO2 <93% on room air at sea level, ratio of arterial partial pressure of oxygen to fraction of inspired oxygen (PaO2/FiO2) <300, or lung infiltrates >50%

    • Critical illness: individuals who have respiratory failure, septic shock, and/or multiple organ dysfunction


  • Many patients with COVID-19 have mild illness or no symptoms; some "asymptomatic test-positive cases" have been found to be pre-symptomatic, testing positive before onset of symptoms.

  • Of patients who develop symptoms, 95% will have symptoms appear within 12 days of exposure.

  • Common symptoms include: fever, shortness of breath/difficulty breathing, cough, shaking/chills, muscle pain, headache, sore throat, abdominal pain/diarrhea, and new loss (or alteration) of taste and smell (43).

  • Modeling data to discern influenza from COVID-19 found influenza initially presents as cough. COVID-19 often begins with fever, followed by URI symptoms, then upper GI and finally lower GI symptoms (44). 

  • Gastrointestinal symptoms (i.e. anorexia and diarrhea), loss of smell, taste, and fever were 99% specific for COVID-19 (a highly specific test, when positive) (45).

  • Most symptomatic cases mount a fever >38°C/100.4°F.

  • Some patients with severe COVID-19 disease who presented initially with milder illness (and seeming improvement in the first week), went on to develop abrupt pulmonary and systemic decompression theorized to be due to "cytokine storm."

  • Activate EMS if any of the following are present:

    • Extreme difficulty breathing (cannot talk without gasping for air)

    • Blue-colored lips or face

    • Severe or persistent pain or pressure in the chest

    • Severe constant dizziness or lightheadedness

    • Acting confused or unable to wake up

    • Slurred speech (new or worsening)

    • New onset seizure or seizures that will not stop

    • Painful red or purple lesions on fingers or toes in the winter (anecdotal)


Risk factors for progression to acute respiratory distress syndrome (ARDS):

  • Age >65 years, neutrophilia, and organ or coagulation dysfunction (46)

  • Chronic lung disease, immunocompromise, obesity (47)

  • Hypertension and diabetes (48)



  • Mild-to-severe respiratory illness with fever, cough, dyspnea, and chest discomfort

  • Wheeze and rales are not typically found

  • Hypoxia. Pulse oximetry may reveal dramatic, relatively asymptomatic hypoxemia. Hypoxemia may be an early diagnostic clue of COVID-19 (49).

  • Livedoid and necrotic skin eruptions (50)


Influenza, other virally-mediated respiratory illness 
  • Influenza and COVID-19 infection share the following characteristics:

    • Fever or feeling feverish/chills

    • Cough

    • Shortness of breath or difficulty breathing

    • Fatigue (tiredness)

    • Sore throat

    • Runny or stuffy nose

    • Muscle pain or body aches

    • Headache

    • Vomiting and diarrhea; more common in children than adults

  • The single factor that distinguishes COVID-19 from influenza is the lose of sensation of taste and smell (seen in up to 60% of patients based upon observational data from Italy) (51).


CDC guidelines on isolation (separation of those with COVID-19 from others) and quarantine (separating from others if you have been exposed to COVID-19) 
  • Quarantine: for those exposed to COVID-19

    • May come out of quarantine after 7 days postexposure if they have no symptoms and have a negative PCR or antigen test result; the specimen for testing may be collected as early as day 5. Without a test, people can end their quarantine after 10 days if they still have no symptoms. The agency says that 14 days is still optimal.

  • Isolation

    • If COVID positive but has no symptoms, they can be with others after:

      • 10 days have passed since the dates you had your positive test

    • If COVID-19 positive and has symptoms, patients may be with others after:

      • At least 10 days since symptoms first appeared and at least 24 hours with no fever without fever-reducing medication and other symptoms of COVID-19 are improving (loss of taste and smell may persist for weeks or months after recover and need not delay the end of isolation)

    • If severe illness from COVID-19 (hospitalized and needed oxygen), healthcare providers may recommend staying in isolation for longer than 10 days after your symptoms first appeared (possibly up to 20 days) and you may need to finish your period of isolation at home (52).

Initial Tests (lab, imaging)

  • Testing options: molecular tests detect the SARS-CoV-2 viral RNA from nasopharyngeal and other respiratory specimens. Serological tests detect the presence of antibodies (IgG;IgM) produced by the immune system in response to the infection.

    • Molecular test: CDC 2019-Novel Coronavirus (2019-nCoV) RT-PCR diagnostic panel (specimens refrigerated at 2-8ºC)

      • Intended for use with upper and lower respiratory specimens collected only from persons who meet CDC criteria for COVID-19 testing

      • Nasopharyngeal swab AND oropharyngeal swab (use only synthetic fiber swabs with plastic shafts with a viral transport media), or oral swabbing AND nasal swabbing on a single swab

      • Systematic review of RT-PCR testing finds false negative rates of between 2% and 29% (sensitivity of 71% and specificity of 95%) for nasopharyngeal swab. As this test is highly specific, when positive, it rules IN disease. However, when negative, repeat testing should be obtained as it does not rule out disease (53).

        • The Abbott ID NOW point-of-care test for SARS-CoV-2 has been recently called into question, as it may have a high false-negative result; if positive, it can be assumed to be a true positive, but if negative, consider further testing (54).

    • Serologic testing for an immune response is best used to determine who has been exposed. Serologic tests are not designed to be diagnostic of infection, but rather as evidence of exposure.

      • The U.S. Food & Drug Administration (FDA) has stated that these tests should only be used by institutions collecting convalescent sera and not for diagnostic purposes (55).

      • Based upon a Cochrane Systematic Review, testing for IgG and IgM antibodies against SARS-CoV-2 found a sensitivity of just 30% during the first week of symptoms, increasing to 91% by the third week. Specificity was above 98%, a high rate of false negatives, but a positive is highly likely to be a true positive (56).

  • PCR tests are more accurate (have a higher sensitivity) but take longer. Antigen tests have a lower sensitivity but a high specificity (57).

    • FDA issued a statement on rapid antigen testing having higher rates of false positives, especially if the end user does not store the testing components properly and readings the outcomes not at the test's specified time (too soon after the required time).

  • Pooled testing: the FDA has issued an emergency use authorization for the Quest Diagnostics RT-PCR test for SARS-CoV-2 to be used with swab specimens pooled from up to four patients. The rationale for pooled testing is if the pool tests negative, all patients are considered negative; if it's positive, each individual sample needs to be retested, saving time and supplies (58).​​​​​

Follow-Up Tests & Special Considerations

  • For worsening symptoms: chest X-ray, confirmatory CT scan. Early CT findings include peripheral ground glass opacities (GGO) which can progress to bilateral or multifocal pneumonia

  • Consider LDH, hsCRP and d-dimer as a baseline.

  • For patients whose symptoms progress from mild to moderate, severe or critical, consider obtaining and monitoring d-dimer, prothrombin time, platelet counts, fibrinogen.

    • Increased d-dimers are reported in patients with severe illness and may predict mortality.

    • A tripling of the d-dimer may predict worsening clinical course.

    • Fibrinogen should be monitored to predict disseminated intravascular coagulation (DIC); nonsurvivors with severe illness have developed DIC around day 4; significant worsening in those parameters at days 10 and 14 was also reported.

    • Prophylactic low-molecular weight heparin (unless there is active bleeding or a platelet count of <25x109/L) is suggested with the hope of lowering the impact of the septic-like coagulopathy and protecting against venous thromboembolism.




  • Resources for healthcare providers from the U.S. CDC can be found at:

  • Current data on critical care can be found at:

  • Continuously updated guidelines from NIH based on severity of illness:

  • Hospital infection prevention and control measures include use of personal protective equipment (PPE) for aerosol, droplet, and contact precautions (e.g. masks, face shields, gloves, gowns), including eye protection (e.g. face shields or goggles) and single-patient dedicated medical equipment (e.g. stethoscopes, blood pressure cuffs, thermometers). Limit the number of individuals and providers entering the room of a patient with COVID-19.

  • If necessary, hospitalized patients with confirmed COVID-19 may be cohorted in the same room. Airborne infection isolation rooms (AIIRs) should be used for patients who will be undergoing any aerosol-generating procedures. During the procedures, all staff should wear N95 respirators or powered, air-purifying respirators (PAPRs).

  • Summary of the care of COVID-19 patients (for the most current information, visit

    • Non-hospitalized patients, hospitalized or are hospitalized but do not require supplemental oxygen

      • In February 2021, the FDA issued Emergency Use Authorization for the monoclonal antibodies bamlanivimab (700 mg) and estevimab (1,400 mg) for the treatment of outpatients with mild to moderate COVID-19 who are at high risk for progressing to severe disease and/or hospitalization (

      • Remdesivir should NOT be used in the outpatient setting but may be initiated for hospitalized patients at high risk for clinical deterioration.

      • Dexamethasone should not be used in outpatients or those who are hospitalized but do not require supplemental oxygen.

      • IL-2 inhibitors (monoclonal antibodies): NIH recommends against the use of tocilizumab or sarilumab for the treatment of non-hospitalized patients with COVID-19, except in clinical trials.


For outpatients, a number of clinical trials are open for you or patients to register and receive treatments by mail and/or in home:

  • Respiratory/ventilatory support (recommendations of NIH updated June 2020):

    • For adults with COVID-19 and acute hypoxemic respiratory failure despite conventional oxygen therapy, the Panel recommends high-flow nasal cannula (HFNC) oxygen over noninvasive positive pressure ventilation (NIPPV).

    • For patients with persistent hypoxemia despite increasing supplemental oxygen requirements in whom endotracheal intubation is not otherwise indicated, the Panel recommends considering a trial of awake prone positioning to improve oxygenation.

    • The Panel recommends against using awake prone positioning as a rescue therapy for refractory hypoxemia to avoid intubation in patients who otherwise require intubation and mechanical ventilation.

    • For mechanically ventilated adults with COVID-19 and ARDS, the Panel recommends using low tidal volume (VT) ventilation (VT 4-8 mL/kg of predicted body weight) over higher tidal volumes (VT >8 mL/kg) (AI).

    • For mechanically ventilated adults with COVID-19 and refractory hypoxemia despite optimized ventilation, the Panel recommends prone ventilation for 12 to 16 hours per day over no prone ventilation.​​​​​​


  • Oxygen

  • Hydration

  • Acetaminophen (max is 1,000 mg every 6 hours in patient without liver disease) given around the clock to address fever

  • Hospitalized adults with COVID-19 should receive VTE prophylaxis per the standard of care for other hospitalized adults (unless there is active bleeding or a platelet count of <25x109/L), with the hope of lowering the impact of the septic-like coagulopathy and protecting against venous thromboembolism (

  • Those who develop thromboembolism should be managed with therapeutic doses of anticoagulant therapy as per the standard of care for patients without COVID-19.

  • Use of NSAIDs in addition to acetaminophen is controversial; there is no data showing they are problematic, but a theoretical rationale should make their use only if acetaminophen is inadequate to maintain fever control.

  • There remains no definitive clinical trial data on the use of vitamin D, vitamin C, or aspirin for COVID-19. Some observational data:

    • Vitamin C: as of November 20, 2020, the NIH states: "There are insufficient data for the COVID-19 Treatment Guidelines Panel to recommend either for or against the use of vitamin C for the treatment of COVID-19 in non-critically ill patients."

    • Vitamin D: there is inconsistent data on the benefit of vitamin D treatment for patients with any stage of COVID-19 infection; the NIH has not updated its recommendation since July 19, 2020, where it stated: "There are insufficient data to recommend either for or against the use of vitamin D for the prevention or treatment of COVID-19."

    • Zinc: the NIH states "there are insufficient data to recommend either for or against the use of zinc for the treatment of COVID-19. The COVID-19 Treatment Guidelines Panel recommends against using zinc supplementation above the recommended dietary allowance for the prevention of COVID-19, except in a clinical trial.

    • Aspirin: due to its inherent anti-inflammatory and anti-thrombotic effects, aspirin is theoretically a possible therapeutic option for COVID-19 patients, but confirmatory data is still being evaluated (60). (See below for further discussion.)


Use of chloroquine or hydroxychloroquine, either alone or with azithromycin, should NOT be prescribed for outpatients. Experimental protocols with sicker inpatients are underway. Use in outpatients may well cause harm and decrease availability of medication for patients with known need (e.g., rheumatoid arthritis, systemic lupus erythematosus).


Patients who have worsening symptoms with declining function should be admitted to the hospital for observation for further deterioration.


First Line

For severely and critically ill patients: 
  • Antibiotics: Consider empiric broad-spectrum antimicrobial therapy for these COVID-19 patients; for patients in shock, empiric broad-spectrum antimicrobial therapy is the standard of care (

  • Dexamethasone: Utilized (at a dose of 6 mg per day for up to 10 days) for the treatment of COVID-19 patients who are mechanically ventilated (AI) and in patients who require supplemental oxygen but who are not mechanically ventilated (NIH Guideline). Dexamethasone improves 28-day mortality compared to placebo in patients requiring IMV (NNT=8.5) and those patients requiring oxygen therapy (NNT=29).


Dexamethasone is not recommended for milder disease and may be harmful (61). Dexamethasone is recommended against for non-hospitalized patients with COVID-19 unless treating other conditions, like asthma or COPD.

  • WHO meta-analysis on the use of steroids on severely ill COVID-19 patients found the 28-day mortality (the primary outcome) was significantly lower in the steroids group (222/678; 32.7%) than in the control group (425/1025; 41.5%); the odds ratio was 0.66 (62).

  • Anti-infectives

    • Baricitnib plus remdesivir was found, in one clinical trial of hospitalized patients with COVID-19, to reduce time to recovery within 29 days after initiating treatment vs. those on placebo with remdesivir. The FDA approved it to be used in combination, but never alone, and ongoing safety and efficacy data is still being studied (63). The NIH states there is not enough evidence to support this combination.

  • Remdesivir: in September, 2020, the WHO recommended against remdesivir (61), but the NIH Panel has not changed their recommendation regarding administering the investigational antiviral agent remdesivir  for 5 days for the treatment of COVID-19 in hospitalized patients with SpO2 ≤94% on room air (at sea level) or those who require supplemental oxygen, and for patients who are on mechanical ventilation or ECMO. Initial data finds recovery is shortened with remdesivir but no mortality benefit has been shown (64). In late August 2020, the US FDA gave emergency authorization despite the drug's limited data or mortality benefit.

    • A study of 600 patients with COVID-19 who did not require oxygen randomized to either a 5- or 10-day course of remdesivir or standard care. At day 11, 5 days of remdesivir  improved survival vs. standard care. There was no difference for the 10-day group, but by day 14, both treatment groups were significantly better than standard care (65).

    • A recent industry sponsored trial of 584 patients with moderate COVID-19 (defined as hospitalized with evidence of COVID-19 pneumonia but no hypoxia) were randomized to 10 days of RDV, 5 days of RDV, or standard care with outcomes measured at “Day 11” on a 7-point ordinal scale. Those in the 5 day arm had significantly better scores than those in the 10 day arm or control groups, but in all groups there was no significant difference in time to recovery, time to improvement in clinical status, or death at 28 days (65).

    • The SOLIDARITY trial (>11,000 hospitalized patients with COVID-19 who were not on mechanical ventilation or ECMO) randomized to study medications that were locally available (lopinavir/ritonavir, hydroxychloroquine, interferon beta-1a, or remdesivir) found no benefit to any of the medications on mortality (66).

      • Despite the SOLIDARITY data, the U.S. FDA voted to approve remdesivir for use in COVID-19 patients who require hospitalization and are at least 40 kg in weight (67).

    • Another RCT of remdesivir found it shortened time to clinical recovery for hospitalized patients with lower respiratory tract disease (10 days vs. 15 days) but without any mortality benefit, except in those who required supplemental oxygen without need for high-flow oxygen or mechanical ventilation (68).

    • Tocilizumab: on March 5, 2021, the NIH COVID-19 Guideline Panel recommended the use of tocilizumab  (single intravenous dose of 8 mg/kg of actual body weight, up to 800 mg) in combination with dexamethasone  (6 mg daily for up to 10 days) in hospitalized patients who are exhibiting rapid respiratory decompensation due to COVID-19. This includes: recently hospitalized patients who have been admitted to the intensive care unit (ICU) within the prior 24 hours and who require invasive mechanical ventilation, noninvasive mechanical ventilation (NIV), or high-flow nasal canula (HFNC) oxygen (>0.4 FiO2/30 L/min of oxygen flow) and patients not in the ICU with rapidly increasing oxygen needs who require NIV or HFNC and have significantly increased markers of inflammation (C-reactive protein [CRP] ≥75 mg/L) (69).

  • ECMO: Venovenous extracorporeal membrane oxygenation (ECMO) has some potential for COVID-19 patients with severe respiratory failure despite receiving invasive mechanical ventilation (70).

  • Famotidine:

    • A retrospective, propensity matched trial of ~900 SAR-CoV-2 patients admitted to the hospital found treatment with famotidine decreased in-hospital mortality (OR = 0.37; CI 0.16 – 0.86, p = 0.021); combined death or intubation (OR = 0.47; CI 0.23 – 0.96, p = 0.040) and lower serum markers of inflammation (71).

    • A post hoc analysis of in-hospital use of famotidine did not find a mortality benefit compared to non-use. It was unclear if pre-hospital famotidine use had any influence of COVID-19 mortality (72).

  • Aspirin: A retrospective, observational cohort study of patients receiving aspirin within 24 hours of admission or those taking aspirin 7 days prior to admission (believed to be for ASCVD prophylaxis) found, after adjusting for confounding variables, aspirin use was associated with decreased risk of mechanical ventilation (adjusted HR 0.56, 95% CI 0.37-0.85, p=0.007), ICU admission (adjusted HR 0.57, 95% CI 0.38-0.85, p=0.005), and in-hospital mortality (adjusted HR 0.53, 95% CI 0.31-0.90, p=0.02). There were no differences in major bleeding (p=0.69) or overt thrombosis (p=0.82) between aspirin users and non-aspirin users. Aspirin was started at time of admission (IQR 0-1 days), median dose was 81 mg (IQR 81-81 mg), and median treatment duration was 6 days (IQR 3-12 days)  (73).

  • A large number of medications remain under investigation: antivirals, immunomodulatory medications (e.g., Regeneron recently stopped trial of polyclonal antibodies in those patients requiring high-flow oxygen or ventilation due to an "unfavorable risk/benefit profile") cytokine inhibitors, and other classes. The following medications are among the better-known examples of medications under investigation:

    • Nebulized interferon beta-1: in a study of ~100 patients hospitalized with COVID-19, nebulized interferon beta-1 x 14 days resulted in clinical improvement at beta-1a is associated with higher odds of clinical improvement at 15 and 28 days (74).

    • Lopinavir-Ritonavir (not effective)

    • Hydroxychloroquine /chloroquine (not effective in prophylaxis or in treatment) with or without azithromycin, and maybe harmful (prolonged QT and increased death)

      • Systematic review of hydroxychloroquine treatment of hospitalized COVID-19 patients did not reduce risk of death or illness vs. standard care. High dose regimens or when combined with macrolides may be associated with harm. Postexposure prophylaxis may not reduce the rate of infection, but the quality of evidence is low (75).

      • In outpatients with ≤4 days of COVID-19 symptoms (with either laboratory-confirmed SARS-CoV-2 infection or epidemiological link to a confirmed COVID-19 case), a randomized clinical trial studied 5 days of hydroxychloroquine or placebo. The treatment and placebo group outcomes were found to not differ in symptom-severity change, hospitalizations, or deaths. But, the hydroxychloroquine recipients had significantly more adverse effects (mostly GI) compared to placebo recipients (43% vs. 22%; number needed to harm, 5) (76).

    • In patients with type 2 diabetes hospitalized with COVID-19, the addition of the dipeptidyl peptidase 4 (DPP-4) inhibitor sitagliptin to insulin treatment was found to lower ICU admission, need for mechanical ventilation use, and mortality risk  (77).

    • Interferons

    • Monoclonal antibodies

    • Ivermectin: NIH continues to recommend against its use as there is insufficient reliable data to support its use (78)

  • Convalescent plasma (sera): Initially promising benefit was reported in critically ill patients, but there has been subsequent conflicting data on its benefit (79). 

    • FDA has granted emergency authorization for use in patients critically ill with COVID-19. This is based on data from the Mayo Clinic of 35,000 patients hospitalized with COVID-19. Outcomes found the 7-day mortality was 8.7% in those transfused within 3 days of diagnosis vs. 11.9% if transfused 4 or more days later. At 30-days, mortality was 21.6% vs. 26.7%, p<0.0001.  It also found transfusions with higher IgG levels (18.45 S/Co) vs. low IgG plasma had lower mortality at 7 and 30 days. Pooled relative risk of mortality with high antibody levels was 0.65 [0.47-0.92] at 7 days and 0.77 [0.63-0.94] at 30 days. This study did not contain a placebo arm and was published without peer review (80).

    • On February 4, 2021, the FDA altered its EUA that only high-antibody-titer convalescent for use in hospitalized patients with COVID-19 early in the disease course and in those hospitalized with impaired humoral immunity (

    • A randomized, controlled study of almost 500 patients in India evaluated convalescent plasma vs. none in addition to the standard of care and found progression to severe disease or all-cause mortality within 28 days was ~18% in all patients, regardless of receiving plasma. Those in the intervention arm did have a higher conversion to a negative SARS-CoV-2 RNA test result, demonstrating efficacy of clearing the virus, but with no impact on clinical outcomes (81).

    • An open-label RCT of convalescent plasma for patients with moderate to severe pulmonary symptoms in COVID-19 across India on progression to severe disease or all-cause mortality at 28 days found no lower risk of severe disease or mortality (81).


If you have a patient who has recovered from COVID-19, and is interested in donating plasma, go to



For any patient meeting criteria for evaluation for COVID-19, clinicians are encouraged to contact and collaborate with their state or local health department. 


Depending on local case rates, elective procedures and surgeries may be postponed. COVID-19 testing is required pre-operatively for elective and emergent procedures. 


  • Review NIH Guidelines as above.

  • Any patient who has had a potential exposure and is ill should NOT enter an ambulatory healthcare facility; remain at home to allow quarantine. Maintain contact via telephone or telemedicine methods.

  • CDC recommends for patients aged ≥2 years to call 911 if any of the following are present:

    • Extreme difficulty breathing (cannot talk without gasping for air)

    • Blue-colored lips or face

    • Severe or persistent pain or pressure in the chest

    • Severe constant dizziness or lightheadedness

    • Acting confused or unable to wake up

    • Slurred speech (new or worsening)

    • New onset seizure or seizures that will not stop


  • Anxiety of patients infected with coronavirus and their close contacts, along with the general population, remains high. Reassure those who test positive to monitor their symptoms and to contact you if they worsen.

  • CDC services include phone and text consultations for these issues at:

  • Depression prevalence in the U.S. has tripled during the pandemic compared to 2017–2018 data. Approximately 1,400 adults surveyed about depressive symptoms in spring of 2020 were compared to ~5,000 adults from the National Health and Nutrition Examination Survey in 2017–2018. In the pre-pandemic cohort, 9% had depressive symptoms vs. 28% during the pandemic; this included a 7-fold increase in risk of severe depression. Populations currently at greatest risk are those with the lowest incomes, where almost 50% had reported depressive symptoms during the pandemic (82).

  • For the general population, offer support and tele-counseling sessions; some therapists are offering this service without charge.

  • Limit anxiolytics as they can compromise symptom recognition in patients who may become ill from any severe illness or infection.

  • Consider cardiac magnetic resonance imaging (MRI) in college athletes before returning to play. A small study of 26 college athletes who tested COVID-19 positive (45% without symptoms) were screened for cardiac manifestations by cardiac MRI after recovery. All had normal electrocardiograms, echocardiograms, and troponin levels. Fifteen percent (all male) had findings consistent with myocarditis with mild (slight shortness of breath) or no symptoms (83).


  • General population: On May 22, 2020, the CDC issued new guidelines on management of COVID-19 patients.

    • People with COVID-19 who experienced symptoms and isolated at home can leave home under the following conditions:

      • If there has not been a test to determine persistent infection, people can leave home after these three things have happened:

        • Afebrile for at least 72 hours (that is three full days of no fever without the use of medicine that reduces fevers) AND

        • Other symptoms have improved (for example, when your cough or shortness of breath have improved) AND

        • At least 10 days have passed since symptoms first appeared

      • If there has been a test to determine persistent infection people can leave home after these three things have happened:

        • Afebrile (without the use of medicine that reduces fevers) AND

        • Other symptoms have improved (for example, when cough or shortness of breath have improved) AND

        • There have been two negative tests in a row, at least 24 hours apart.

    • People who DID NOT have COVID-19 symptoms, but tested positive and have isolated at home can leave home under the following conditions:

      • If there has not been a test to determine persistent infection, people can leave home after these two things have happened:

        • At least 10 days have passed since the date of the first positive test AND

        • Symptoms have not appeared (no cough or shortness of breath) since the test

      • If there has been a test to determine persistent infection, people can leave home after:

        • There have been two negative tests in a row, at least 24 hours apart.

    • Note: if you develop symptoms, follow guidance above for people with COVID-19 symptoms (84).

  • Healthcare workers: On April 30, 2020, the CDC offered the following Return to Work guidelines, "Return to Work Criteria for HCP with Suspected or Confirmed COVID-19."

    • Symptomatic HCP with suspected or confirmed COVID-19

      • Either strategy is acceptable depending on local circumstances

        • Symptom-based strategy. Exclude from work until:

          • At least 3 days (72 hours) have passed since recovery defined as resolution of fever without the use of fever-reducing medications and improvement in respiratory symptoms (e.g., cough, shortness of breath); and,

          • At least 10 days have passed since symptoms first appeared

        • Test-based strategy. Exclude from work until:

          • Resolution of fever without the use of fever-reducing medications, and

          • Improvement in respiratory symptoms (e.g., cough, shortness of breath), and

          • Negative results of an FDA Emergency Use Authorized COVID-19 molecular assay for detection of SARS-CoV-2 RNA from at least two consecutive respiratory specimens collected ≥24 hours apart (total of two negative specimens). See Interim Guidelines for Collecting, Handling, and Testing Clinical Specimens for 2019 Novel Coronavirus (2019-nCoV). Of note, there have been reports of prolonged detection of RNA without direct correlation to recovery of live, infectious virus from viral culture.

    • HCP with laboratory-confirmed COVID-19 who have not had any symptoms

      • Either strategy is acceptable depending on local circumstances

        • Time-based strategy. Exclude from work until:

          • 10 days have passed since the date of their first positive COVID-19 test assuming they have not developed symptoms since their positive test. If they develop symptoms, then the symptom-based or test-based strategy should be used. Note, because symptoms cannot be used to gauge where these individuals are in the course of their illness, it is possible that the duration of viral shedding could be longer or shorter than 10 days after their first positive test.

        • Test-based strategy. Exclude from work until:

          • Negative results of an FDA Emergency Use Authorized COVID-19 molecular assay for detection of SARS-CoV-2 RNA from at least two consecutive respiratory specimens collected ≥24 hours apart (total of two negative specimens). Note, because of the absence of symptoms, it is not possible to gauge where these individuals are in the course of their illness. There have been reports of prolonged detection of RNA without direct correlation to viral culture.

    • Note that detecting viral RNA via PCR does not necessarily mean that infectious virus is present.

    • Consider consulting with local infectious disease experts when making return to work decisions for individuals who might remain infectious longer than 10 days (e.g., severely immunocompromised).

    • If HCP had COVID-19 ruled out and have an alternate diagnosis (e.g., tested positive for influenza), criteria for return to work should be based on that diagnosis.


The American Academy of Pediatrics recommends youth athletes with COVID-19 who have had moderate symptoms (e.g., prolonged fever), cardiac symptoms, or other concerning findings should undergo electrocardiography prior to returning to play sports and may need pediatric cardiology for clearance to return to sports. Serum enzyme levels and EKG findings that are normal should not be considered adequate for return unless there are no symptoms, especially chest pain/pressure or dyspnea as MRI findings show a subset of young athletes have a persistent myocarditis that is not identified on blood or EKG testing. Any abnormal cardiac finding must return to normal before the athlete returns to play (85).


Patient Monitoring

Encourage those who test positive to monitor their breathing, and if they develop dyspnea with activity or at rest, to contact their PCP or be seen in an emergency department. 


  • Frequently clean hands by using alcohol-based hand rub or soap and water.

  • When coughing and sneezing, cover mouth and nose with flexed elbow or tissue. Throw tissue away immediately and wash hands.

  • Avoid close contact with anyone who has fever and cough.

  • If you have fever, cough, and difficulty breathing, seek medical care early.

  • Wear a face mask when in public and unable to remain at least 6 feet from others.

  • For patients on PPIs, consider switching to an H2RA (famotidine 20 mg BID or nizatidine 150 mg BID).

  • As vitamin D deficiency increases risk of COVID-19 infection and severity of disease, consider recommending to patients to take 2–4,000 IU vitamin D per day. While not proven to be protective, vitamin d deficiency is common, and there is little risk at this dose (

  • Medications and other therapies written for the general public can be found at

  • Urge patients NOT to seek out hydroxychloroquine for prevention or treatment of COVID-19.

  • Patients with COVID-19 should continue taking their angiotensin-converting-enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs).

    • A statement from the American Heart Association, the Heart Failure Society of America, and the American College of Cardiology (86) initially supported this position and 3 recent studies have found no worsening of outcomes of COVID-19 infections based upon anti-hypertensive agent being taken (87). A recent single-center case of 362 patients hospitalized with COVID-19 infection found no difference in severity of the disease, complications, and risk of death in those who were taking ACEIs/ARBs compared with those not on these medications (88).

  • Patient resource on home care:

  • All should try to get 30 minutes of exercise per day. A survey study of ~370 adults' health and wellbeing after one month of confinement due to COVID-19 in China found those who stopped working reported worse mental and physical health conditions. This was mitigated by exercise for ≤30 minutes per day (89).


  • 80% of patients have mild, self-resolving illness requiring no intervention.

  • A study compared ~46,000 patients hospitalized with influenza during the 2018–2019 flu season and 90,000 hospitalized with COVID-19 from March through April. The in-hospital mortality rate for COVID-19 was 3 times higher than influenza (17% vs. 6%). For adolescents, in-hospital mortality was 10 times higher with COVID-19 (1.1% vs. 0.1%). COVID-19 patients were more likely than flu patients to develop acute respiratory failure, pulmonary embolism, septic shock, or hemorrhagic stroke but were less likely to experience myocardial infarction or atrial fibrillation (90).

  • Observational data from Indiana found the infection fatality ratio of 0.26% of those not institutionalized aged 12 and older. Higher infection fatality ratios were seen in those aged 60 and older (1.71%) (this does not include those in nursing homes, rehabilitation centers, etc.) and among non-whites (0.59%). The infection fatality ratio of those aged 65 and older for the seasonal influenza is ~0.8% (91).

  • U.S. mortality compared to other western countries: mortality data through September 19, 2020 found the mortality rate in the U.S. was 60.3/100,000 compared to Australia (3.3 deaths per 100,000), Canada (24.6 per 100,000), Italy (59.1/100,000), and Belgium (86.8 per 100,000).

    • Outcomes if the U.S. death rates were comparable to other similar countries:

      • If like Australia, the U.S. would have had 187,661 fewer COVID-19 deaths.

      • If like Canada, 117,622 fewer deaths

  • CDC data on prognosis in those under age 20 years found:

    • ~70% of deaths occurred in those aged 10 through 20 years, 20% aged 1 through 9, and 10% under 1 year with Black and Latino youth accounting for ~75% of those who died.

    • Predisposing conditions of those who died include chronic lung disease (mostly asthma), obesity, neurologic/developmental conditions, and cardiovascular syndromes (92).

  • Duration of immunity from infection is unknown. While reinfection has occurred with other coronaviruses, they typically occur months to years after the initial infection (93).

  • Immunity persistence is unclear; from a study of 82 confirmed and 58 probably cases of COVID-19 from China, the median duration of IgM detection was 5 days (interquartile range, 3-6), while IgG was detected at a median of 14 days (interquartile 10-18) after symptom onset (94).

  • A small U.S. study followed antibody levels after mild COVID-19 in 34 patients with mild COVID-19 using serial anti-SARS-CoV-2 receptor binding domain IgG levels. The estimated mean IgG half-life was 36 days (95).

  • There remains conflicting data on persistence of antibody response in those already infected with the virus, with some showing loss of antibodies within a few weeks, while others show persistence up to 120 days after infection (96).

  • A recent report on 185 adults who recovered from COVID-19 (most with mild symptoms found levels of spike-specific memory B cells increased over the initial 4-6 months with SARS-CoV-2 spike IgG titers, showing only modest declines at 6-8 months (97).

  • U.S. cohort data tracked estimated excess deaths in the U.S. between March 1 and May 30, 2020, and compared it to data from January 5, 2015 through January 25, 2020. During these three months in 2020, there were 780,975 total deaths; 122,300 more deaths than expected from previous years, with COVID-19 accounting for 78% of these deaths, implying significant under-reporting (98).

  • Laboratory findings that correlate with an increased mortality include leukocytosis with lymphopenia, and highly-elevated LFTs, creatinine, lactate dehydrogenase, troponin, N-terminal-pro-brain natriuretic peptide, and d-dimer compared to those who recovered.

  • Morbidities that correlate with death include acute respiratory distress syndrome, sepsis, acute cardiac injury, heart failure, acute kidney injury, and encephalopathy (99).

  • UK cohort data of neurologic outcomes of COVID infection included cerebrovascular events and mental status changes (encephalopathy, encephalitis) (100).

  • Postinfection neuropsychiatric disorders were studied in a systematic review and meta-analysis of 65 studies and 7 preprints from multiple countries.

    • From the 25 studies of SARS and MERS:

      • Insomnia (41% of patients), anxiety (36%), concentration impairment (38%), memory difficulties (34%), depression (33%), and confusion (27%)

      • After the infection (60 days to 12 years), 40 studies found traumatic memories (30%), emotional lability (24%), memory impairment (19%), fatigue (19%), irritability (13%), anxiety (12%), insomnia (12%), pressured speech (12%), euphoria (11%), and depression (10%) with a prevalence of 15% for depression and for anxiety, and 32% for post-traumatic stress disorder (PTSD).

    • Of the 12 COVID-19 studies:

      • Findings included acute-phase delirium, agitation, and alterations in consciousness, with some cognitive dysfunction after hospitalization (101).

  • An Italian cohort study of 143 patients hospitalized for COVID-19 evaluated symptoms at a mean of 60 days after symptom onset and 36 days after hospital discharge. Mean age of 56.5 years, 37% were women, and the mean length of hospitalization was 13.5 days. During hospitalization, 73% had interstitial pneumonia, 15% required noninvasive ventilation, and 5% received mechanical ventilation. Participants were virus-free by PCR. Only 13% of participants reported being symptom-free but 55% had 3 or more symptoms. The most common persistent symptoms were fatigue 53%, dyspnea 43%, joint pain 27%, and chest pain 22%. Compared to pre-COVID-19 infection, 44% reported their quality of life was ≥10 points lower on a scale of 0 (worst health) to 100 (best health) (102).


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  • The disease results from a novel virus, newly named coronavirus 2 (SARS-CoV-2).

  • The syndrome may lead to death, particularly in elderly and immune-compromised individuals.

  • Modeling data to discern influenza from COVID-19 found influenza initially presents as cough, while COVID-19 often begins with fever, followed by URI symptoms, then upper GI and finally lower GI symptoms. The single factor that distinguishes COVID-19 from influenza is the loss of sensation and smell. 

  • Gastrointestinal symptoms (i.e. anorexia and diarrhea), loss of smell, taste, and fever were 99% specific for COVID-19 (a highly specific test, when positive).

  • Use of NSAIDs in addition to acetaminophen is controversial; while there is no data showing they are problematic, consider using only if acetaminophen is inadequate to maintain fever control.