Traces the genetics of coronavirus would be almost as important in people infected with the COVID-19, whether they have or not symptoms of the disease, according to a study in south korea.
The scientists from the University of Soonchunhyang, Seoul, analyzed data on 303 patients infected by the COVID-19 who stayed for the month of march in a center of temporary isolation established in the suburbs of the south Korean capital.
During their isolation, 89 individuals (29,4 %) have never developed symptoms although they have received a diagnosis of COVID-19 positive – and therefore fall in the group of ” asymptomatic “.
In addition, 21 employees (6.9 %) did not show any symptoms to their arrival at the centre, but developed it later. So they were presymptomatic.
All other individuals had symptoms as early as their arrival.
The patients were typically young adults with no other health problem. All were tested periodically at the level of the nose, throat and saliva to check for the presence of the virus.
The result is the most surprising is that the viral load of asymptomatic patients was “similar” to that of symptomatic patients. The study was published this week in the journal JAMA Internal Medicine. Another interesting fact : people asymptomatic have healed slightly more quickly than the other, receiving a first negative result, on average, at day 17 of their isolation, compared to days 19 or 20 for those who had symptoms.
The researchers call “a high” viral load found in hiv infected individuals and asymptomatic, suggesting that they ” could be a key factor in the spread within the community “.
However, they acknowledge that their study “was not designed to determine” and are therefore not a definitive answer to this question.
In fact, scientists have not been able to do it themselves for the collection of data, but rather analyzed the results of the 1886 tests that have been requested by the medical staff who was at the bedside of the 303 patients. Thus, they have not been able to verify if the genetic material of the virus that was identified was infectious or not, since the method used to detect the virus without regard to the fact that he is alive or dead.
Epidemiological studies and experimental wider will be necessary to establish with certainty the risk of contagion posed by asymptomatic individuals, the researchers write.
According to them, a precautionary principle should apply and it is necessary to encourage the screening of intensive population and the research of contacts to allow to trace and isolate the carriers silencing of the COVID-19.