Here’s what you need to know about the SARS-CoV-2 virus and the disease it causes, called COVID-19.
At 2:24 the video states, “So far, evidence suggests that this coronavirus is spreading mostly from people who do feel sick, traveling from person to person in tiny droplets.” However, multiple preliminary studies have since suggested that the virus can spread from infected people who have not developed symptoms: https://bit.ly/2w4R7iI, https://bit.ly/2R6eakG, https://bit.ly/2UAqtru.
At 2:42 William Hanage says, “It’s not yet clear how long these droplets can survive on surfaces.” A study published in the New England Journal of Medicine on March 17, 2020, showed that SARS-CoV-2, the virus that causes COVID-19, can remain viable in aerosols for three hours, on copper for up to four hours, on cardboard for up to 24 hours, and on plastic and stainless steel for up to two to three days: https://bit.ly/2R3jhSK.
What We Know and Don’t Know about the Coronavirus
Published: March 10, 2020
Onscreen: There are hundreds of known coronaviruses that can infect birds and mammals. We know of 7 that have infected humans.
Amira Roess: Coronaviruses all belong to the same family, and we call them coronaviruses because if you look at the outside structure of the virus, they look like crowns. And in Latin, “corona” means crown.
Alok Patel: This is why it got its name. It's not named after the beer.
Onscreen: The official name for the coronavirus causing the epidemic today is SARS CoV-2—a coronavirus that's never been seen in humans before. It can cause a respiratory illness called Coronavirus 2019, or COVID-19, with flu-like symptoms.
William Hanage: The first two major symptoms observed in the majority of cases are a dry cough and fever.
Onscreen: Another potential symptom is shortness of breath. Sometimes the infection becomes severe and can even be fatal.
Roess: Individuals with underlying respiratory conditions, like asthma or tuberculosis or some other respiratory illness, are more prone to getting a severe infection from COVID-19.
Patel: The data’s showing that the elderly or people with other medical conditions are at most risk of getting severe illness or dying.
Onscreen: It's not clear yet why some people get sicker than others. Not everyone who gets severely ill has an underlying condition.
Roess: We're constantly analyzing the data to understand who is most at risk for dying from COVID-19.
Onscreen: One group of people has not gotten very sick.
Patel: Children are not getting as severe of infections with this coronavirus.
Onscreen: And the reasons for that are not clear. Among the adults known to be infected, the majority of cases so far have been mild. But we don't yet know the exact percentage.
Hanage: At present there is still a lot of uncertainty as to how much of the disease is comparatively mild. So, if it is mostly comparatively mild, that sounds like it's good—but actually it comes with a kicker, which is it's much more difficult to control.
Onscreen: That's because if infected people don't feel very sick, they're more likely to go to school, to work, to the store, to a theater, where they can spread the virus.
So far, evidence suggests that this coronavirus is spreading mostly from people who feel sick, traveling from person to person in tiny droplets.
Hanage: Droplets are the small little sort of blobs of fluids that we emit when we cough or sneeze or even talk.
Onscreen: Droplets can also be passed from hands to surfaces.
Hanage: It's not clear how long this virus can survive on surfaces, but it could survive for quite a long time.
Onscreen: Other coronaviruses have survived up to nine days.
If you touch that surface and then touch your nose, mouth, or eyes, the virus can get into your body and cause infection.
Will the virus spread less when the weather turns warmer?
Hanage: There is virtually no evidence that the coming change in the seasons will help at all. China has really quite varied climatic conditions—from very humid places like Hong Kong in the South to parts of the North, which are much colder and less humid—and they found virtually no difference. I also note that it's been transmitting quite well in Singapore and Singapore is on the equator. So, this suggests that different climatic conditions are not going to have a major impact.
Onscreen: There's still a lot researchers don't know about COVID-19, including how many people have been exposed or infected.
Epidemiologists like William Hanage would like to see a serological survey that examines blood samples to assess whether a person has been exposed.
Hanage: If you have those data then you have be going to be able to be much, much more precise about how many people were exposed, how many people got infected, how many had mild disease, how many of the children became infected, whether or not there is actually a different attack rate across the different age cohorts.
All of that at the moment is mostly speculation. But with this, we'd be able to actually say something sensible about how lethal it is.
Onscreen: In the meantime, people can take steps to reduce their risk of getting COVID-19.
Hanage: People should be aware that this is an extremely serious situation. They should also not feel helpless. It's not a time to panic, but it is a time to prepare and there's a bunch of stuff that we can all do which will make us much less likely to get infected—and if we're less likely to get infected, we're less likely to transmit it to our communities and other people, including our loved ones.
Onscreen: Protect yourself from those droplets that could carry the coronavirus. Stay away from people who are sick, if you can.
Patel: A lot of people out there clamoring to go and buy masks. If you're healthy and you have no symptoms, and you are not around other people who may be sick, you don't need to go out and buy a mask. Now, if you are sick, wearing the correct type of mask may prevent you from spreading the disease to other people.
Onscreen: Keep your hands clean.
Patel: What people need to do is follow really strict hygiene precautions and that includes washing your hands either 20 seconds with soap and water or with hand sanitizer, making sure that you are not touching your eyes and your nose.
Roess: We recommend eating a healthy diet, lots of fresh fruits and vegetables, stay hydrated, get plenty of rest and sleep. That is really important for boosting your immune system and helping your body fight pathogens before they make you sick.
Hanage: Even if we cannot keep the virus out forever, we can still slow it down. And every moment we can slow it down buys us time, makes less stress on health care, and enables us to hopefully get to the point when we're going to be able to move past this.
Digital Producer: Ana Aceves
Research and Production: Sukee Bennett, Angelica Coleman, Ari Daniel, Robin Kazmier, Christina Monnen
Shutterstock, Videoblocks, Scientific Animations Inc./Wikimedia Commons, F.A. Murphy, S. Whitfield, CDC
NIAID, Alissa Eckert, MS, Dan Higgins, MAMS, NIAID-RML, Banej/Wikimedia Commons
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