(Photo : Reuters)
A passenger wearing a protective mask arrives at a railway station in Wuhan on the first day inbound train services resumed following the novel coronavirus disease (COVID-19) outbreak, in Wuhan of Hubei province, the epicentre of China's coronavirus outbreak

Headed by Dr Li Tan of the General Hospital of Central Theater Command of PLA in Wuhan, he and a team of researchers shared on the scientific website medRxiv- in which medical papers are uploaded before being printed and analyzed by peers- their recent findings while studying the case of a patient who continued shedding for 49 days.

In their report, they discussed the case of the middle-aged man suffering from the coronavirus who remained contagious for 49 days and who may have formed a 'symbiotic relationship' with the virus. This phenomenon has never been recorded before.

He displays mild symptoms all that time while he is suffering the disease. It was not until the doctors injected him with the blood of somebody who had fully recovered that he shook the infection off.

Period of Viral Shedding

The man was tested positive of COVID-19 on February 8 at a hospital in Wuhan after having high temperature for a week, but he did not report suffering from any symptoms. His swab tests resulted positive on days 17, 22, 26, 30, 34, 39, 43, and 49. He did not, however, test positive on the 47^th day, but this could have been an aberration.

On average, a person infected by the virus shall have a viral shedding - the time wherein a sufferer can affect others - of approximately 20 days and longest previously case reported lasted for 37 days. It is also commonly known that the longer a person is infectious for, the more severe symptoms that a person is suffering.

However, this seems not to be true to this man's case who has the most prolonged duration of viral shedding and yet only reported mild symptoms of the disease.

Dr Tan said, "The Case 1 only got moderate fever initially, and the body temperature rapidly decreased into normal levels without any respiratory failure."

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Chronic Mutation

The researchers are not sure whether the type of virus the man has belongs to S type or it is a mutated L type or maybe a new subtype. L type is proven to be more prevalent and is more aggressive than the S type.

The study authors think that Case 1 could be an original new subtype that is yet to be identified. It may be a chronic type without infusion treatment, and the virus and the host may even have a symbiotic relationship.

They warned that there could be more "chronically infected patients," but are most often neglected- because they show mild or no symptoms at all- that can spread the virus to their surroundings and cause a new outbreak.

The critical question for these cases is how long will this kind of patients remain infectious and whether they can infect through a new route of transmission, such as sexual transmission.

In a previous article from Science Times, they mentioned there that Dr Christian Drosten published his scientific research in the journal Nature discussing that the shedding of the virus occurs most likely earlier during when patients still have mild symptoms.

Also Read: More Evidence Indicate Seemingly Healthy People Spread Coronavirus Faster Than You Think