Two papers published Friday in the journal the Lancet offer some of the first rigorous analyses of patients who contracted a novel coronavirus that has broken out in China and spread to other countries. Among their discoveries: The virus does not only affect people with other, underlying health conditions, and people who are not showing symptoms can still be carrying the virus.
In one study, researchers analyzed data from the first 41 patients who were admitted to hospitals with confirmed cases of the infection in the central Chinese city of Wuhan, where the outbreak is believed to have originated last month. Two-thirds had been to a large seafood market that also sold wild animals for meat and is thought to be where the virus jumped from an animal source to people. The median age of the patients was 49.
About a third of the 41 patients needed intensive care, and six of them died. Some of the patients with more serious illnesses suffered from a dangerous immune system overreaction called a CYTOKINE STORM.
One child with the virus did not show any symptoms. Health authorities have said that people with the virus have shown a range of symptoms, from very mild to very severe. But an asymptomatic infection raises the question of whether people have to be showing signs of the disease to pass it to people, a question that experts are rushing to answer.
In a commentary piece also published Friday by the Lancet, Dr. David Heymann, an infectious disease epidemiologist at the London School of Hygiene and Tropical Medicine, wrote that “the picture these two manuscripts paint is of a disease with a 3-6 day incubation period and insidious onset.”