Muge Cevik, a virologist at the University of St. Andrews in the United Kingdom, has noted that the two largest factors in the spread of the virus are close contact and crowding in closed spaces. Anywhere that has seen large amount of people crowded into places, we have seen large numbers of infected people. In his studies and throughout reviewing papers and other studies, he has determined that doing things like going out to eat together and being in public transport risk spreading the disease, but she says that he doesn’t think “going to a market briefly, for five minutes or a transient encounter while you walk or run past someone” are as high of risks for spreading the virus.
Studies that Muge has gone over have come from places like China, Singapore, Taiwan, and some from the United States. The studies not in the US were done through contact tracing, whereas studies done here involving contact tracing, hasn’t even hardly started. When surveying people coming into hospitals in New York City in May, it was revealed that most of them had been home, and weren’t going into work or even taking public transport. Which leads many people to wonder how they are even being infected if the virus takes close contact to spread.
Cevik says that each infected individual is transmitting the virus to between two and three others on average, which is key, that is only the average. In reality, most people don’t transmit the virus to anyone, or maybe just one person, but a minority infect many others in so-called super-spreading events. The data show that nine percent of infected people are responsible for 80% of the transmissions, and we are still trying to learn how that could be possible.
One of the main theories is that the disease is very infectious but only for a short window. Contact tracing studies show, “People are most infectious right around the onset of symptoms, as well as a couple of days before and after.” Cevik noted that people with severe symptoms were more likely to transmit the virus to others. But this doesn’t necessarily help us understand spreading in cases for people who are Asymptomatic. Erin Bromage, a biology professor at the University of Massachusetts, Dartmouth explained recently that even people exposed to sick family members in their homes don’t always get sick. We are still learning many things about how the virus spreads, and one thing to be sure about, is that we’re going to need many more studies on it to fully understand it.
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