The Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) have identified an outbreak of respiratory illnesses caused by a novel coronavirus originating in Wuhan, China.  This post is being updated as of March 18, 2020, with data available as of March 17.  The WHO Director-General announced at a media briefing that the COVID-19 outbreak has now been classified as a pandemic. As of March 17, 2010, the WHO reports a total of 179,111 global cases with 7,426 mortalities. Click HERE for an interactive map from the WHO depicting the current COVID-19 pandemic.  A total of 81,116 cases are within China, with 3,231 associated mortalities.  In Italy, there have been 27, 980 cases with 2,503 mortalities. According to WHO data, There have been a total of 3,503 cases in the United States with 58 associated mortalities.  This includes repatriated cases. The severity of the outbreak has already surpassed the SARS epidemic in 2002 in terms of infected cases.

Coronaviruses comprise a large family of viruses and are a frequent cause of the common cold. Some cause less-severe disease, but more rarely, can cause severe disease as seen with the 2002 severe acute respiratory syndrome (SARS) and 2012 Middle East respiratory syndrome (MERS) outbreaks. The 2002 SARS epidemic, which originated in China, caused 8,300 illnesses and 785 mortalities.  A total of 1,879 cases of MERS have been reported with a 39% mortality rate.

The mode of transmission of COVID-19 is by respiratory aerosol and is spread from person-to-person.  However, all coronaviruses do not spread from person-to-person. For example, the primary mode of transmission of MERS was camel-to-human transmission, with the rates of human-to-human transmission being very low. Initially, the likelihood of human-to-human transmission of COVID-19 was thought to be very low. The outbreak has a possible zoonotic origin, as it has been linked to a large seafood and animal market.  However, medical workers caring for patients in Wuhan city have become infected with the virus suggesting human-to-human transmission.  

Individuals with pre-existing lung disease, those that are elderly, and those with other chronic illnesses such as heart disease appear to have a higher risk for severe COVID-19 illness.  Everyday preventative behaviors are the most effective method to avoid COVID-19 infection.  These measures include frequent hand washing, covering coughs, and staying home when sick.  While most cases are mild, serious illness occurs in about 16% of cases. The estimated mortality is about 3% according to WHO data as of March 3, 2020. 

On March 9, 2020, the WHO Director provided a media briefing to provide an update on the COVID-19 epidemic.  He emphasized that "we are not at the mercy of this virus".  He also reported that of the cases in China, "70% have recovered and been discharged".  He noted the overall goal is to stop transmission and prevent viral spread. He said that the approach in each country must be tailored due to the uneven distribution of the epidemic across the globe.  He did encourage that areas with community spread consider cancelling mass gatherings and implementing school closings.  The WHO Director also announced financial aid donations toward the WHO's Strategic Preparedness and Response Plan from several countries including 300 million dollars from the United States and donations from Azerbaijan, China, the Republic of Korea, and the Kingdom of Saudi Arabia.

The CDC and WHO have been working tirelessly to quickly develop and implement testing for COVID-19.  The CDC developed an rRT-PCR test for rapid diagnosis.  As of March 13, a total of 81 laboratories in the United States are offering testing.  On March 4, the CDC updated its criteria to guide evaluation of persons under investigation for COVID-19.

Certain travel bans have been instituted in order to slow the spread of COVID-19.  These include travel restrictions to China, Iran, and Europe. Please refer to the Proclamation on Declaring a National Emergency Concerning the Novel Coronavirus Disease (COVID-19) Outbreak for more information.  Further, on March 14, 2020, the POTUS announced additional travel restrictions were extended to the United Kingdom and Ireland.

 Additionally, many schools and colleges are choosing to facilitate classes from home using distance learning mechanisms in order to prevent viral spread. Further, many workplaces are encouraging work-from-home duties when feasible to help reduce the possibility of viral spread.  Many large theme parks, stores, and areas of recreation are choosing to close out of caution as well. On March 16, 2020 the POTUS issued Coronavirus Guidelines for the United States of America encouraging individuals to avoid discretionary travel, stay home when possible, work from home, avoid gatherings of 10 or more people, avoid bars and restaurants and continue practicing good hygiene.  These guidelines are to stay in place for 15-days in efforts to slow the spread of the coronavirus. 

According to the CDC, the potential public health threat posed by COVID-19 is high, both globally and to the United States, but individual risk is dependent on exposure. The CDC notes that for the general American public, the overall risk is low as they are unlikely to be exposed to the virus at this time.  The CDC warns that certain populations, such as healthcare workers are at an increased risk of exposure due to the possibility of caring for patients infected with the virus. CDC has developed guidance to help in the risk assessment and management of people with potential exposures to COVID-19.

Read more:

Review of Medical Microbiology & Immunology: A Guide to Clinical Infectious Diseases, 15e: Chapter 38: Respiratory Viruses

The Centers for Disease Control and Prevention: 2019 Novel Coronavirus (COVID-19), Wuhan, China

World Health Organization: Coronavirus disease (COVID-19) outbreak