What are coronaviruses?

What are coronaviruses?

Reposted from original blog, published on July 16, 2018

By Julie T. Shapiro, UFBI Fellow

You might not have heard of coronaviruses, but maybe you have heard of SARS (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Syndrome). These two diseases were both caused by coronaviruses that originated in animals and “spilled over” to people. SARS first broke out in China in 2002 – 20031–3, while MERS first broke out in Saudi Arabia in 20134,5. Although both diseases were contained, during both outbreaks there were fears of an even more serious global epidemic6,7. Both had high rates of reported mortality: 9.6% for SARS8 and 35% for MERS9. In addition to SARS and MERS other coronaviruses can cause milder, cold-like infections in people 10,11. The name “coronavirus” comes from the shape of the virus. Corona means crown in Latin and the shape of the virus makes it look like it has a crown or halo around it. You can see a picture in one of the early scientific articles on coronaviruses here.

Free-tailed bat (Chaerephon pumilus)

Coronaviruses are currently classified in four groups. The Alpha- and betacoronaviruses originate in bats, while the gamma- and deltacoronaviruses originate in birds12. In bats, these viruses are found in the gastrointestinal tract, but they can also infect the respiratory tract of other organisms, including people12. They do not appear to make the bats sick. Coronaviruses appear to switch hosts very easily16 and in addition to infecting people, have “jumped” over to many other species, including cats13, whales14, and pigs15.

As a UFBI Fellow, I am analyzing data on coronaviruses in the little free-tailed bat (Chaerephon pumilus) from Swaziland and the way anthropogenic disturbance might affect the prevalence and diversity of these viruses. The SARS epidemic, and the discovery of SARS-like coronaviruses in bats in China, spurred a lot of further research to discover new coronaviruses16 and many bats around the world appear to host them17. With every study, new coronaviruses are discovered. However, there are over 1100 species of bat18 and we have not yet studied coronaviruses in all of them. If we do not even know all the coronaviruses that are out there, we cannot understand why or how some of them spillover to people (or other animals). It is important to document as many coronaviruses as possible and then study how factors, such as anthropogenic disturbance, might affect both the diversity of different coronaviruses that bats host and the prevalence of these viruses. This information might help us predict and prevent future outbreaks of coronavirus disease.




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