About 40 percent of COVID-19 positive patients in Wuhan, capital of central China’s Hubei Province, have antibodies that can offer protection against being reinfected with the virus for at least nine months, said a new article published in the medical journal The Lancet this week.

According to the study, the first long-term seroprevalence survey in Wuhan, the adjusted COVID-19 positive rate in the city hardest hit by the virus earlier last year was just 6.9 percent, indicating that only a small proportion of the city population was infected after the epidemic outbreak.