In a strange case causing concern, a group of Brazilian scientists analyzes the medical history of a patient who gave positive of coronavirus in PCR tests for 218 days, period in which the virus replicated and even mutated.
This is a man in his 40s who, before suffering from covid-19, had gone through aggressive cancer treatment, which left his immune system weakened. This was pointed out by a note from the São Paulo State Research Amparo Foundation (FAPESP).
The patient tested positive for the disease (covid) from September 2020 to April of this year.
The research – published on the medRxiv platform and which has yet to be reviewed by other experts – was conducted by scientists from the University of Sao Paulo (USP), who discovered that the virus was not only present in the patient’s body, but also he replied for a good part of that time.
“During all that period there was a risk of transmission to other people “, explained María Mendes-Correa, professor at the USP School of Medicine and first author of the research.
This was corroborated in in vitro examinations from nasopharyngeal and saliva samples extracted weekly and in which, after a few hours, it was possible to appreciate a increased viral load.
“That replication capacity of the virus was observed continuously and persistently over a period of 196 consecutive days “Mendes-Correa said.
Between January and April of this year they also collected samples of blood, urine, and anal region. These data also indicated the persistence of SARS-CoV-2 throughout much of the study period.
On the other hand, serological tests revealed that at no time did the patient develop antibodies.
.On the other hand, the scientists also detected pathogen mutations throughout the infection process, from the genetic sequencing of nasopharyngeal samples.
Some of these mutations occurred in the ‘spike’ protein, which the virus uses to penetrate human cells.
“The data suggest” that this evolutionary process of the virus “has occurred within the same host, when normally “these changes” are observed in the community, “Mendes-Correa pointed out.
“ That is a worrying phenomenon, as it favors the emergence of viral variants better adapted to the human organism, “he added.
The patient in question remained a good part of the time admitted to the hospital and in the short periods of time in which he was at home, he also remained isolated.
With 505,000 deaths and more than 18 million positives, Brazil is the country of Latin America hardest hit by the coronavirus pandemic, the second in the world with the most deaths linked to the disease and the third with the most infections, behind the United States and India.
With information from EFE