Relapses of already cured people worry doctors. Wuhan imposes 14 days of isolation on those who are considered healed
A father and daughter in the city of Xuzhou, in the Chinese province of Jiangsu, have become the last known cases so far of a group that continues to grow: that of patients infected with the new coronavirus who recover for, after a few days or weeks, test positive again. A phenomenon that worries doctors, as it can make Covid-19, the disease caused by the virus, more difficult to eradicate.
According to the Chinese state media, the father, the first confirmed case in that city, had been discharged from the hospital two weeks ago, but in a new test he has returned to be positive as a carrier of the virus. Her young daughter, who had also been declared cured, has yielded the same result. Both have been admitted again.
Two days earlier, the local government of Japan’s Osaka prefecture had confirmed another similar case: that of a tourist guide in her forties who had fallen ill in January and had been discharged in early February. He showed symptoms again, such as a dry cough and chest pain, and on February 26, he tested positive. This patient had not returned to work, had remained at home, had not maintained close contact with anyone and had always worn a mask when leaving.
Other cases of new positives have been detected throughout China among people declared to have been cured previously. A study carried out among patients who left the hospital in the province of Canton, in the southeast, found that 14% of the cases were positive again, according to the Caixin magazine on Tuesday .
The concern about possible reinfection has led authorities in Wuhan, the city where the epidemic originated, to order patients Covid-19 receiving discharge from the hospital have to spend a quarantine fourteen days in a specially enabled before to be able to return to normal life.
Experts see several possible explanations for a discharged affected person to relapse again. One possibility is that a small amount of virus has been left in the body, insufficient to test positive, but enough to reproduce and test positive again if the body has not developed antibodies in adequate amounts to fight it. It is also possible that this lack of antibodies allows a second infection from external sources.
“It is a pattern that has occurred in outbreaks of other diseases,” recalls Professor of Statistical Epidemiology Christl Donnelly of Imperial College London and the University of Oxford. In the case of the Ebola epidemic in West Africa between 2013 and 2016, for example, there were cases in which, when the tests were repeated before final discharge, relapses were recorded. “It is also possible that it occurs as in the case of herpes zoster, the consequence of a previous infection with the chickenpox virus, in which the virus is dormant in some part of the body,” for years.
The question in these positive cases after healing, Donnelly points out, is that “we do not know if these affected people can infect other people later. If it did, it would cause those apparently recovered cases to be a potential source of infection, which would be somewhat concerning. We have to wait and see what happens to these people, and carefully follow the clinical data that comes out. “
The National Commission of Health in China has declared this Friday that the first examinations of these patients have found that they are not infectious. Another possibility that is handled is that, at least in some cases, the tests to register are not done correctly. Or that they have been done correctly and thrown false negatives: Dr. Li Wenliang, who tried to raise the alarm at the beginning of the crisis that died of Covid-19 on February 6, tested negative several times before his confirmation was confirmed. infection.
Speaking to People’s Daily , the Communist Party of China newspaper, the deputy director of the infectious disease center at West China Hospital explained that doctors initially took samples from the nose and throat to determine if a patient was a carrier of the coronavirus. Other more recent tests find traces of the pathogen in the lungs.
In Japan, the criteria for discharging a Covid-19 patient foresee that the patient test negative 48 hours after he has stopped presenting severe symptoms, and that the result is the same in a second test twelve hours later.
In China, patients must test negative, have no symptoms, and their lungs must be free from abnormalities on a CT scan image.
At a press conference this week, the deputy director of the Canton Center for Disease Control and Prevention, Song Tie, said that none of the second-infected patients appears to have infected the people around him. “From what we understand, after someone has been infected by this type of virus, they will produce antibodies, and after these antibodies have been produced, it will not be contagious.”
So far, of more than 78,000 people infected with the coronavirus in China since the crisis began two months ago, 36,117 have already been discharged, almost half.
The Mazatlan Post