What is SARS-CoV-2?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for the COVID-19 pandemic. The virus is spread primarily through transmission of respiratory droplets during face-to-face contact. Infection with SARS-CoV-2 may or may not cause symptoms, and when symptoms are present, they can be mild, moderate, or severe. 1

Symptoms appear 2 to 14 days after being exposed to COVID-19. The most common symptoms of COVID-19 at presentation: 2


Loss of smell

Nasal obstruction

Weakness and lack of energy



Muscle aches and pain

Runny nose

Loss of taste

Sore throat


Clinical manifestations: 3

Asymptomatic or presymptomatic





Disease Characteristics - NIH

Asymptomatic or Presymptomatic

Individuals who test positive using a virologic test but who have no symptoms that are consistent with COVID-19

Mild illness

Various symptoms (eg, fever, cough, sore throat, headache, malaise, muscle pain, etc.) without shortness of breath, dyspnea, or abnormal chest imaging

Moderate illness

SpO2 ≥94% on room air and lower respiratory disease evidenced by clinical assessment or imaging

Severe illness

SpO2 <94% on room air, PaO2/FiO2 <300, respiratory rate>30 breaths/min, or lung infiltrates >50%

Critical illness

Respiratory failure, septic shock, and/or multiorgan dysfunction

When to get tested for SARS-CoV-2 infection 4

If you have symptoms of COVID-19

If you have been within 6 feet of an infected person for a total of 15 minutes or more over a 24-hour period with someone who has tested positive for COVID-19

If you have traveled, attended large social gatherings, or have been in a crowded indoor setting

If you have been asked to get tested by a healthcare provider, state, tribal, local, or territorial health department

Following an exposure to someone with COVID-19, you do not have to get tested for SARS-CoV-2 infection: 4

If you have been fully vaccinated

If you have recovered from COVID-19 within the past 3 months as long as you don’t develop new symptoms

Know your risk factors for COVID-19

If you have mild symptoms of COVID-19, you can recover at home without medical care. If your symptoms get worse, contact your healthcare provider. If you or someone else is showing signs of severe COVID-19, seek emergency medical care immediately. The emergency signs include: 5

Trouble breathing

Persistent pain or pressure in the chest

New confusion

Inability to wake or stay awake

Pale, gray, or blue-colored skin, lips, or nail beds, depending on skin tone

Know your risk factors for severe COVID-19 6


Chronic kidney disease

Chronic lung diseases (eg: COPD, asthma, interstitial lung disease, cystic fibrosis, pulmonary hypertension)

Dementia or other neurological conditions

Down syndrome

Heart conditions (eg: heart failure, coronary artery disease, or cardiomyopathies)

HIV infection

Immunocompromised state (weakened immune system) from solid-organ transplantation

Liver disease

Overweight (BMI >25 kg/m2 but <30 kg/m2), obesity (body-mass index>30 kg/m2 but <40 kg/m2), or severe obesity (BMI ≥40 kg/m2)

Older adults

People from racial and ethnic minority groups

People with disabilities


Sickle cell disease or thalassemia

Smoking, current or former

Solid organ or blood stem cell transplant

Stroke or cerebrovascular disease

Substance use disorders

Type 1 or 2 diabetes mellitus

COVID-19 Monoclonal Antibody Therapy for Nonhospitalized Patients

Dual monoclonal antibody cocktails with emergency use authorization (EUA) contain two potent antibodies that bind to different receptors of the SARS-CoV-2 spike protein and prevent them from entering host cells. Two monoclonal antibody cocktails can be used in nonhospitalized patients with mild to moderate symptoms of COVID-19:

Bamlanivimab and etesevimab 7

Casirivimab and imdevimab 8

These therapies must be given as soon as possible and within 10 days of symptoms for the treatment of mild-to-moderate COVID-19 in patients: 7, 8

Who are at least 12 years of age and weigh at least 40 kg

Have positive results of direct SARS-CoV-2 viral testing

Who are at high-risk of progressing to severe COVID-19 or hospitalization

Are you a candidate for monoclonal antibody therapy?

Click on the link to the monoclonal antibody eligibility tool for patients which will guide you through a series of questions to determine if you are eligible for these infusion therapies. You may also download and print a copy of the decision tree to share with your healthcare provider.

COVID-19 Monoclonal Antibody Eligibility Tool for Patients

What does it feel like to have monoclonal antibody therapy?

Watch this video to hear people share their experience with these infusion therapies for COVID-19.

If you would like to learn more about COVID-19 monoclonal antibody infusion therapies, visit these websites:




Recommended Treatment Options for Hospitalized Patients 6

Treatment Guidance

Recommended for hospitalized patients with severe COVID-19

Most benefit seen in those with severe COVID-19 on supplemental oxygen rather than patients on mechanical ventilation or ECMO


Recommended for hospitalized patients with severe COVID-19

Not recommended for hospitalized patients without hypoxemia requiring supplemental oxygen

Baricitinib + Remdesivir

Combination recommended over remdesivir alone in those who cannot receive corticosteroids because of a contraindication


Recommended in addition to standard of care in hospitalized patients with progressive severe or critical COVID-19 who have elevated markers of systemic inflammation

Vaccines Approved for Prevention of COVID-19

COVID-19 vaccines help to develop immunity without having to get the illness. COVID-19 vaccines with EUA:

Pfizer-BioNTech COVID-19 vaccine 9

Moderna COVID-19 vaccine 10

Janssen COVID-19 vaccine 11

Variants of the COVID-19 virus

Viruses are constantly changing, and new variants emerge over time. Sometimes they emerge and then disappear, sometimes they emerge and persist. Variants of concern are those that may be more easily spread, cause more severe disease, reduce efficacy of vaccines and treatments, and create diagnostic challenges compared with strains that were previously circulating. 12

Variants of concern of the COVID-19 virus that were first identified abroad are now circulating in the United States, in addition to two variants first identified in California: 11

B.1.1.7 (United Kingdom)

B.1.351 (South Africa)

P.1 (Brazil)

B.1.427 (California)

B.1.429 (California)


1 Wiersinga WJ, Rhodes A, Cheng AC, et al. Pathophysiology, transmission, diagnosis, and treatment of coronavirus disease 2019 (COVID-19): a review. JAMA. 2020;324(8):782-793.

2 Lechien JR, Chiesa-Estomba CM, Place S et al. Clinical and epidemiological characteristics of 1420 European patients with mild-to-moderate coronavirus disease 2019. J Intern Med. 2020;288(3):335-344.

3 NIH. Clinical spectrum of SARS-CoV-2 infection.
https://www.covid19treatmentguidelines.nih.gov/overview/clinical-spectrum/. URL accessed April 2, 2021.

4 CDC. Test for Current Infection.
https://www.cdc.gov/coronavirus/2019-ncov/testing/diagnostic-testing.html. URL accessed April 2, 2021.

5 CDC. What to Do If You Are Sick.
https://www.cdc.gov/coronavirus/2019-ncov/if-you-are-sick/steps-when-sick.html. URL accessed April 2, 2021.

6 CDC. People with Certain Medical Conditions.
https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-with-medical-conditions.html. URL accessed April 2, 2021.

7 Bhimraj A, Morgan RL, Shumaker AH, et al. IDSA Guidelines on the treatment and management of patients with COVID-19. Infectious Diseases Society of America 2021; Version 4.1.1. Available at
www.idsociety.org/practice-guideline/covid-19-guideline-treatment-and-management/. Accessed April 2, 2021.

8 FDA. Fact Sheet for Health Care Providers Emergency Use Authorization (EUA) of Casirivimab and Imdevimab. Available at
https://www.fda.gov/media/143892/download. Accessed April 2, 2021.

9 FDA. Fact Sheet for Health Care Providers Emergency Use Authorization (EUA) of Bamlanivimab and Etesevimab. Available at
https://www.fda.gov/media/145802/download. Accessed April 2, 2021..

10 FDA. Pfizer-BioNTech COVID-19 Vaccine. Available at
https://www.fda.gov/emergency-preparedness-and-response/coronavirus-disease-2019-covid-19/pfizer-biontech-covid-19-vaccine/. Accessed April 2, 2021.

11 FDA. Moderna COVID-19 Vaccine. Available at
https://www.fda.gov/emergency-preparedness-and-response/coronavirus-disease-2019-covid-19/moderna-covid-19-vaccine/. Accessed April 2, 2021.

12 FDA. Janssen COVID-19 Vaccine. Available at
https://www.fda.gov/emergency-preparedness-and-response/coronavirus-disease-2019-covid-19/janssen-covid-19-vaccine/. Accessed April 2, 2021.

13 CDC. SARS-CoV-2 Variant Classification and Definitions. Available at https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/variant-surveillance/variant-info.html#Concern. Accessed April 2, 2021.