A research letter published this week describes the case of a woman in China who spread COVID-19 to five people without displaying any symptoms. Share on Pinterest Can asymptomatic SARS-CoV-2 carriers pass the virus on? All data and statistics are based on publicly available data at the time of publication. Some information may be out of date. Visit our coronavirus hub and follow our live updates page for the most recent information on the COVID-19 outbreak. The CDC recommend that all people wear cloth face masks in public places where it is difficult to maintain a 6-foot (2-meter) distance from others. This will help slow the spread of the virus from asymptomatic people and people who do not know that they have contracted it. People should wear cloth face masks while continuing to practice physical distancing. Instructions for making masks at home are available here. Note: It is critical that surgical masks and N95 respirators are reserved for healthcare workers. Although international efforts to curb the coronavirus outbreak are in full swing, some view this recent finding as a cause for concern. To date, the vast majority of cases have occurred in China, but the virus has now spread to 29 other countries. Scientists have demonstrated that the new virus, dubbed SARS-CoV-2, can be passed from human to human. Studies have also shown that some people can be infected by the virus but display few or no symptoms. The recent paper, published in JAMA, is the first to describe an asymptomatic carrier passing on the virus to others.

Wuhan to Anyang The paper outlines the experiences of five individuals with respiratory symptoms and fevers who were admitted to the Fifth People’s Hospital of Anyang, in China, and one family member with no symptoms. The asymptomatic individual is a 20-year-old woman who lives in Wuhan. She traveled to see family in Anyang, more than 400 miles (645 kilometers) away. After a few days, five of her relatives developed symptoms of SARS-CoV-2 infection, and she was isolated and placed under observation. The woman from Wuhan experienced no respiratory or gastrointestinal symptoms and no fever, cough, or sore throat. A CT scan showed no abnormalities. Following further tests, doctors found that her C-reactive protein levels were normal, meaning that there was no inflammation. The woman’s lymphocyte counts were also normal, indicating that there was no immune response. However, real-time reverse transcriptase polymerase chain reaction tests confirmed that she had been infected with SARS-CoV-2. All five of her family members — four women and one man — developed COVID-19. None had visited Wuhan or had contact with anyone else who had visited Wuhan.