Coronavirus disease 2019 (COVID-19) was first associated with a cluster of pneumonia cases during December 2019 in Wuhan, China. After rapid spread of the disease across China and to several countries,1  the World Health Organization declared a global health emergency on January 30, 2020, followed by a global pandemic on March 11, 2020.

Coronaviruses are a large family of viruses that are widespread among birds and mammals and cause a variety of illnesses. The virus that causes COVID-19 is an enveloped single-strand RNA zoonotic virus associated with a severe respiratory syndrome.2  Spread occurs via human-to-human transmission primarily by inhalation of large respiratory droplets associated with coughing, sneezing, singing, or talking (these heavy droplets may travel 6 feet [1.8 m] or more but fall relatively quickly), or tiny aerosolized particles (< 5 μm in diameter) that are light and thus can stay suspended in the air for hours, especially...

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