Wuhan Coronavirus: What are the facts?

Michael Doney MD, MS, MPH is Color’s Head of Medical Affairs. Before joining Color, Michael worked at the US Centers for Disease Control & Prevention (CDC), where he served as Associate Director, Preparedness & Response in the Division of Global Migration and Quarantine and as a Medical Officer in the Emergency Preparedness and Response Branch, Division of Preparedness & Emerging Infections. Michael also has experience working on seasonal and pandemic influenza vaccines.

The Wuhan Coronavirus, a new respiratory virus identified in Wuhan, China, is making headlines all over the world. And just like the virus, misinformation is spreading. Today, we’re sharing suggestions on where to find up-to-date and reliable information about this most recent outbreak.

First things first, what is a Coronavirus?

Coronaviruses are a large family of viruses that cause a wide range of respiratory illnesses, ranging from the common cold to more serious diseases like Severe Acute Respiratory Syndrome (SARS). These types of viruses are zoonotic, meaning they can infect and spread between animals and humans. The name coronavirus stems from the latin term “corona” meaning crown or halo, and refers to the spike proteins found on the surface of the virus that give the virus a crown-like appearance.

This new virus, referred to as the Wuhan coronavirus or 2019-nCoV, is a new type of coronavirus that was first identified in Wuhan, China.

How have advancements in genetic sequencing contributed to knowledge about the Wuhan coronavirus?

While there is still a lot we don’t know about the Wuhan coronavirus, advancements in sequencing technology have allowed researchers to respond more quickly to this outbreak. During the 2003 SARS coronavirus outbreak, it took over three months to sequence the entire SARS genome.¹ In contrast, it only took scientists a month to sequence the entire Wuhan coronavirus genome and the genome has already been shared widely with researchers around the world.² This is important for two reasons: it allows researchers to track mutations in the virus and it provides researchers with clues on the emergence of the virus and may provide insight into treatment and prevention.

The dissemination of the sequenced viral genome has already led to an improved understanding of the Wuhan coronavirus. Recent findings showed that the Wuhan coronavirus is genetically similar to a SARS-like coronavirus found in bats, which suggests bats were the original source of this outbreak.³

How concerning is the virus?

There are many factors that contribute to the impact of an infectious disease outbreak, such as the contagiousness of the virus and the severity of the associated disease. To measure how contagious a virus may be, scientists use a value called R₀ (pronounced “R nought”). The R₀ is a measure of the expected number of cases generated by a single case in a susceptible population, or in other words, the number of people to whom an infected person may be expected to spread the illness. Thus, the greater the value of R₀, the more contagious a virus is expected to be. For example, measles, which is a highly contagious respiratory disease, has an estimated R₀ between 12 and 18.⁴ This means that on average, each person infected with measles will spread the infection to another 12–18 people if preventive measures, like immunization, aren’t taken. Early reports suggest that the R₀ of the Wuhan coronavirus is between 1 and 3.⁵ In comparison, the CDC estimated the R₀ of the seasonal flu to be around 1.3 and the R₀ of the SARS coronavirus was around 3.

 

In addition to how many individuals an infected person is likely to spread the illness to, another factor to be considered is the severity of illness. So far, the Wuhan coronavirus appears to be less deadly than the prior SARS coronavirus outbreak, with early reports suggesting that 2–3% of those who become infected with the Wuhan coronavirus will die.⁶ As a comparison, around 0.01% of those who become infected with the seasonal flu die each year and overall about 10% of those infected with the SARS coronavirus during the 2003 outbreak died. It is important to note that early estimates of disease severity and lethality are subject to change as we gain more insight into the numbers of persons infected and the spectrum of milder to more severe disease. Like many respiratory viruses associated with pneumonia, this virus is more dangerous for older people or those who are in poor health.

Should you worry about becoming infected in the US?

The good news is that since the virus is not widespread in the United States the chance of becoming infected in the US is currently low. To date, the majority of reported cases have been in mainland China. While there have been several cases reported in the US, the CDC is being vigilant. Those who have been infected are being isolated and quarantine of close contacts is being utilized in an attempt to prevent the virus from spreading within the community. You can find the current number of coronavirus cases in the United States on the CDC’s website.

What steps can you take to stay healthy?

As with most viruses, the best way to protect yourself from infection is to avoid being exposed to the virus. The CDC suggests these preventive actions to prevent the spread of respiratory infections:

– Avoid close contact with people who are sick.

– Avoid touching your eyes, nose, and mouth with unwashed hands.

– Wash your hands often with soap and water for at least 20 seconds. Use an alcohol-based hand sanitizer that contains at least 60% alcohol if soap and water are not available.

– The CDC does not currently recommend the use of face masks among the general public as there has only been limited person-to-person spread among close contacts at this time.

Where is the best place to go to find accurate and up-to-date information about the virus?

The best place to find accurate and up-to-date information will be from local, state, and/or government public health agencies like the Centers for Disease Control. You can find information about the coronavirus from the CDC on their 2019 Coronavirus website.

The following are also good sources for information:

– FAQ and Answers about the 2019 Novel Coronavirus (CDC)

– 2019-Novel Coronavirus Situation Summary (CDC)

– What to do if you are sick with 2019 Novel Coronavirus (CDC)

– Novel Coronavirus 2019 (World Health Organization)


References

1. Leung FC. Hong Kong SARS sequence. Science. 2003;301(5631):309–310.

2. Zhou P, Yang X-L, Wang X-G, et al. Discovery of a novel coronavirus associated with the recent pneumonia outbreak in humans and its potential bat origin. bioRxiv. January 2020:2020.01.22.914952. doi:10.1101/2020.01.22.914952

3. Zhu N, Zhang D, Wang W, et al. A Novel Coronavirus from Patients with Pneumonia in China, 2019. N Engl J Med. January 2020. doi:10.1056/NEJMoa2001017

4. Guerra FM, Bolotin S, Lim G, et al. The basic reproduction number (R0) of measles: a systematic review. Lancet Infect Dis. 2017;17(12):e420-e428.

5. Zhao S, Lin Q, Ran J, et al. Preliminary estimation of the basic reproduction number of novel coronavirus (2019-nCoV) in China, from 2019 to 2020: A data-driven analysis in the early phase of the outbreak. Int J Infect Dis. January 2020. doi:10.1016/j.ijid.2020.01.050

6. Huang C, Wang Y, Li X, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet. January 2020. doi:10.1016/S0140–6736(20)30183–5