Presymptomatic people have COVID and are not yet showing symptoms of the virus but eventually do. According to a study published by the Journal of the American Medical Association (JAMA) on Jan. 7, 35 percent of new COVID cases stem from presymptomatic spread. People can have the virus for days before showing any sign of symptoms. “The time from exposure to symptom onset (known as the incubation period) is thought to be three to 14 days, though symptoms typically appear within four or five days after exposure,” according to Harvard Health. Not only are you contagious before symptom onset, but you’re also potentially the most contagious at that time. “Emerging research suggests that people may actually be most likely to spread the virus to others during the 48 hours before they start to experience symptoms,” per Harvard Health. And for more up-to-date information, sign up for our daily newsletter. Some people never go on to develop COVID symptoms—these people are asymptomatic. While researchers have yet to pin down the definitive percentage of asymptomatic cases, various studies have hovered around more than 40 percent, according to the Advisory Board. The JAMA model found that 24 percent of COVID cases come from these asymptomatic cases. And for coronavirus symptoms you should know, This Strange Pain Could Be the First Sign You Have COVID, Study Says. When the presymptomatic and asymptomatic spread are combined, they account for almost 60 percent of the virus’ spread. It’s challenging to combat a virus that’s invisible in some people, but experts say adhering to precautions, such as wearing a mask and maintaining social distance, could help control the spread.ae0fcc31ae342fd3a1346ebb1f342fcb “The bottom line is controlling the COVID-19 pandemic really is going to require controlling the silent pandemic of transmission from persons without symptoms,” study co-author Jay C. Butler, the CDC deputy director for infectious diseases, told The Washington Post. And for more on the current state of the pandemic, These 3 States Have the Worst COVID Outbreaks in the Entire World. JAMA’s model confirmed what many other studies have found, which is that people without COVID symptoms are responsible for the majority of the virus’ transmission. “It’s certainly confirmatory, but it’s nice to see confirmation,” epidemiologist Richard Menzies, MD, told The Washington Post. And for more on coronavirus, If You Have These 4 Symptoms, You Could Have Longer Immunity to COVID.
