Can the newest coronavirus spread through a handshake? Or by sharing shopping carts or subway hanging straps? Here’s what you need to know about how COVID-19 spreads from person to person
With more than 73,000 people confirmed with COVID-19 infection as of Feb. 18, and nearly 2,000 deaths around the world, questions about how the virus spreads are becoming more urgent.
Here’s what you should remember: COVID-19 spreads when the virus responsible for the disease, SARS-CoV-2, a coronavirus, is transmitted by one person to another in respiratory droplets. That means the virus can spread when an infected person coughs or sneezes and releases these droplets into the air, where they are either inhaled by others, or can land on other people’s mouths or noses if they’re near enough—generally a distance of about six feet (1.8 meters). Once the virus finds itself inside a new human host, it can start infecting cells and cause disease.
The other thing to keep in mind is that while doctors are still learning about how this particular coronavirus behaves in the human body, it seems that SARS-CoV-2 is more likely transmitted when the infected person already has symptoms of COVID-19, including fever, cough and shortness of breath. Based on the cases described so far, doctors believe it could take SARS-CoV-2 anywhere from two to 14 days to cause symptoms, so for now, they are assuming that the virus can be spread at any time during that period.
Since the disease spreads via respiratory droplets, neither a handshake or fist bump would be a primary way to pass along the virus. An infected person would have to sneeze or cough into his hand, touch someone else’s hand, and that second person would then have to place that hand in close contact with their nose, mouth or even eyes to get infected with any virus that might still be on the hand’s surface. So there’s no real reason that fist bumps are any safer than shaking hands when it comes to COVID-19. And no reason to avoid shaking hands for that matter either.
As with handshakes, touching infected surfaces isn’t a major source of transmission, since the SARS-CoV-2 virus is most efficiently spread by respiratory droplets. Still, if the virus lands on a surface after an infected person coughs or sneezes, and another person touches that surface soon afterward and then touches their nose, mouth or eyes, there is a small possibility the virus could be transmitted. Experts aren’t sure yet how long the virus can survive on such objects, but for viruses in general, it’s not very long.
It’s all about proximity. Since COVID-19 is spread by respiratory droplets, the important and limiting factor is how far those droplets can travel when someone sneezes or coughs. Typically, experts say that’s about six feet, or a little under two meters. This means that the people sitting closest to a person infected with SARS-CoV-2 are at highest risk of getting infected.
At the moment, experts at the U.S. Centers for Disease Control and Prevention (CDC) don’t recommend that healthy people wear face masks in public. For now, it’s more important for people who are infected to consider wearing them with their doctor’s recommendation in order to prevent spreading the virus to health care workers and others who are physically close to them.
There are a range of different types of masks. Disposable paper masks can help to reduce the chances of spreading infected droplets, and they should be thrown out after each use. Masks like N95, named because they are designed with better filters to block about 95% of small particles people breathe in, are meant for health care workers who have more direct and sustained contact with infected patients and are at higher risk of being exposed to SARS-CoV-2. But for most people, the CDC is currently not recommending the use of either type.
For healthy people, frequent hand-washing is one of the best ways to ward off SARS-CoV-2, since that can remove any virus-containing droplets on your hands that could make it to your nose or mouth. Health officials say using soap and water should be the first choice for washing hands, since the lather created by scrubbing your hands with soap can dislodge germs effectively. Experts have recently backed away from recommending alcohol-based hand sanitizers; although they are effective in killing some germs, they can also contribute to the rise of antibiotic-resistant bacteria that are harder to treat and kill.
And for those who are sick, covering coughs and sneezes with a tissue is another critical way to prevent any virus, not just SARS-CoV-2, from traveling to another person.
