Coronavirus (COVID-19): What You Need to Know

This is a rapidly evolving situation. Last updated Friday, Dec. 18, 2020.

The “2019 novel coronavirus” (COVID-19) is a new coronavirus and the responsible agent for an outbreak of pneumonia cases in Wuhan City, Hubei Province, China. COVID-19 was initially reported to the World Health Organization (WHO) on December 31, 2019 with links to a large seafood and animal market. The virus is transmitted via infectious secretions (respiratory droplets, sputum, serum, or blood) between individuals in close contact (within about 6 feet). It is possible that, in addition, the virus can be transmitted by saliva, urine, and stool.

On March 11, 2020, the WHO declared COVID-19 a global pandemic.

The situation is rapidly evolving. There have been more than 75 million confirmed human infections and more than 1.6 million deaths worldwide as of December 18, 2020. In the United States alone, there are more than 17 million confirmed cases. For an up-to-date heat map of global cases, click here.

Per the CDC, health care providers should immediately notify their local or state health department in the event of the identification of a person under investigation (PUI) for COVID-19


Multiple vaccines for COVID-19 have been under development. On December 11, 2020, the FDA issued an EUA for the Pfizer-BioNTech COVID-19 vaccine for individuals aged 16 years and older. The vaccination series is 2 doses given 3 weeks apart. As of December 15, 2020, a Moderna vaccine is on track for FDA authorization for use in individuals 18 years of age or older.

Because demand is expected to exceed initial supply, the US Advisory Committee on Immunization Practices (ACIP) has recommended that when a COVID-19 vaccine is authorized by the FDA and recommended by ACIP, the following groups be offered vaccination in the initial phase of the COVID-19 vaccination program:

  • Healthcare personnel
  • Residents of long-term care facilities
What to look for:

Signs and symptoms of illness vary, and some people with COVID-19 infection can be relatively asymptomatic. Most patients, however, will experience one or more of the following over the course of disease:

  • Fever or chills
  • Cough
  • Dyspnea
  • Fatigue
  • Myalgias
  • Headache
  • New-onset anosmia or ageusia
  • Sore throat
  • Congestion or rhinorrhea
  • Nausea or vomiting
  • Diarrhea

In children:

What else could it be:

The differential diagnosis of COVID-19 includes other etiologies of lower respiratory tract infection.

Viral infection:

Bacterial pneumonia, eg:

Bacterial pneumonia, eg:

Atypical bacterial pneumonia, eg:


If you suspect COVID-19:

Clinicians should use their judgment to determine if a patient has signs and symptoms compatible with COVID-19 and whether the patient should be tested. Most patients with confirmed COVID-19 have developed fever and/or symptoms of acute respiratory illness (eg, cough, difficulty breathing).

Contrary to CDC recommendations, the WHO does not recommend use of Airborne Precautions unless the patient is undergoing high-risk interventions for aerosolization (intubation, induced sputum, etc). Currently, all US providers should follow CDC recommendations.

Refer to the WHO for additional guidance for suspected COVID-19 infection.

Management of COVID-19 depends on the severity of illness.

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