Cases of COVID-19 reported in multiple areas of the US in early February. Risk to public is low. Use basic health precautions.

Severity: Informational Alert

The locations affected by this alert are:

  • Chicago, Illinois
  • Los Angeles, California
  • Washington, DC
  • Boston, Massachusetts
  • Baltimore, Maryland
  • Phoenix, Arizona
  • San Antonio, Texas
  • Madison, Wisconsin
  • Orange County, California
  • Everett, Washington
  • Mesa, Arizona
  • Santa Clara, California
  • Anaheim

This alert began 01 Mar 2020 02:41 GMT and is scheduled to expire 31 May 2020 23:59 GMT.

  • Event: Imported cases of coronavirus disease (COVID-19), limited local transmission
  • Location(s): Multiple areas (map)
  • Period: January-March 2020
  • Cases: 26

US authorities have identified 26 presumptive positive cases of coronavirus disease (COVID-19), including 16 laboratory-confirmed cases, according to data through Feb. 29. Most of these were imported cases from areas with ongoing outbreaks, primarily China. Authorities identified a presumptive positive case of COVID-19 in an individual hospitalized in Washington, DC, late Feb. 29, and are transporting the individual to a containment facility in Baltimore, Maryland, for continued treatment in isolation. The designated regional hospital epidemiology and infection control center is The Johns Hopkins Hospital in downtown Baltimore. The risk to the wider public remains low; additional cases may be identified in the coming weeks in the Washington, DC area as authorities trace the person's close contacts.

Health officials in Seattle and King County, Washington, reported three new cases late Feb. 29, including two cases, one resident and one healthcare worker, at a long-term care facility. Authorities will likely identify additional cases among residents of the long-term care facility, where the residents are typically older individuals and those with chronic medical conditions.

Confirmed and presumptive positive cases have been identified in:

  • Arizona: Maricopa County
  • California: Humboldt, Los Angeles, Orange, Sacramento, San Benito, San Diego, Santa Clara, Orange, and Yolo counties.
  • Illinois: Chicago, Cook County
  • Maryland: Baltimore (transported there from Washington, DC No exposure to the public in Baltimore).
  • Massachusetts: Boston, Suffolk County
  • Washington, DC
  • Washington State: King and Snohomish counties
  • Wisconsin: Madison County
  • Texas: San Antonio County

All individuals are receiving treatment in isolation until their symptoms resolve. The risk to the public remains low. This represents the latest case count as of Feb. 29.

Background and Analysis
Older individuals, infants, and those with chronic illness are more susceptible to infection and are at increased risk for severe complications. Human-to-human transmission can occur, though it remains unclear how easily the virus spreads between people. Preliminary investigations indicate the course of illness is not as severe as seasonal influenza, nor as contagious.

Coronavirus disease 2019 (COVID-19) is a viral respiratory disease caused by infection with the SARS-CoV-2 virus (previously known as 2019-nCoV). Symptoms occur 1-14 days following exposure (average of 3-7 days). These symptoms include fever, fatigue, cough, difficulty breathing, sometimes worsening to pneumonia and kidney failure - especially in those with underlying medical conditions.

Emphasize basic health precautions, especially frequent handwashing with soap and water, or an alcohol-based hand sanitizer if soap and water are unavailable. Practice good coughing/sneezing etiquette (i.e., covering coughs and sneezes with a disposable tissue, maintaining distance from others, and washing hands). There is no evidence that the influenza vaccine, antibiotics, or antiviral medications will prevent this disease, highlighting the importance of diligent basic health precautions.

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