A research letter published this week describes the case of a woman in China who extended COVID-19 to five people without showing any symptoms.
While international efforts to curb the coronavirus outbreak are in full swing, some see this recent finding as a concern.
To date, the vast majority of cases have occurred in China, but the virus has now spread to 29 other countries.
Scientists have shown that the new virus, called SARS-CoV-2, can be transmitted from human to human. Studies have also shown that some people may be infected by the virus but show few or no symptoms.
The recent article, published in JAMA, is the first to describe an asymptomatic carrier that transmits the virus to others.
What does this mean?
A letter published in The New England Journal of Medicine on January 30 described a similar case. She reported that a woman from Shanghai, who had no symptoms, had transmitted the infection to a German man.
The authors of the letter write that “The fact that asymptomatic people are potential sources of infection may [SARS-CoV-2]warrant a re-evaluation of the transmission dynamics of the current outbreak.”
However, it turned out that the woman had experienced mild symptoms, such as muscle pain and fatigue. The authors had not been able to speak directly to the woman before the material was published.
Information on this outbreak is published quickly and comprehensively; During an epidemic, everyone focuses on bringing data into the public domain.
In an interview with Science, Professor Marc Lipsitch, an epidemiologist at Harvard T.H. Chan School of Public Health, boston, MA, explains how these situations can change the way scientific evidence is compiled and published:
“I think peer review is lighter in the midst of an epidemic than at normal speed, and also the quality of the data entering the documents is necessarily more uncertain.”
Overall, the current case study is compelling, but more research is needed.
It is also worth noting that asymptomatic carriers do not sneeze or cough, which are some of the main ways the virus spreads. Because of this, it is not clear how much role these individuals could play in the transmission of SARS-CoV-2.
