[ad_1]
Asymptomatic and even mild cases of Covid-19 do not offer immunization against the disease, according to a new Fiocruz study published Wednesday. Published in the Social Science Research Network, the work reinforces the idea that reinfection by SarsCov2 is possible and can result in serious illness. In other words, the population is even more vulnerable to the pandemic than previously thought.
The lead author of the study, virologist Thiago Moreno, said he accelerated the dissemination of the results as much as possible due to a question of social responsibility.
“I feel like a matter of social responsibility to make it known as soon as possible,” Moreno said, recalling that we are on the eve of the Christmas season and vacation travel. “If you have ever had an asymptomatic or mild infection, it does not mean that you will not have it again, or that it will be mild again.”
The study was carried out at the Center for Technological Development in Health (CDTS / Fiocruz) based on the sequencing of genotypes of the new coronavirus. The study followed four people weekly who had not shown any symptoms since the start of the pandemic in March. Serological tests and RT-PCR were performed on all the subjects followed and all were positive, although they were asymptomatic.
By sequencing the genomes, the researchers confirmed that one person contracted the virus associated with an imported genome and another had a viral structure associated with the genome already circulating in Rio de Janeiro.
According to Moreno, one of the volunteers again sought out the research group in late May, citing stronger signs and symptoms of COVID-19, such as fever and loss of taste and smell.
“When we did RT-PCR again, all four subjects tested positive. What we observed was a reinfection in the family environment ”, explained the researcher. “However, the person who presented the genotype associated with imported cases in March was now infected with another strain. The other individual, who had been infected with the genotype circulating in Rio, remained with the same genotype, but already had some accumulated mutations, which allowed us to interpret that it was a reinfection and not a persistence of the infection ”.
For the virologist, the work reinforced the notion that reinfection is possible, something common among respiratory viruses. According to him, the first exposure to the virus did not guarantee an immune memory of the organism.
“People with asymptomatic or very mild cases, if they are exposed to the virus again, they can have an infection again,” he said. “This time, it may be a more serious infection than the first, as research shows.”
When the organism is invaded by some foreign microorganism, it initially launches a generic response to combat the invader. Since this response is not specific, it does not generate a memory of the invasion, although it does manage to overcome the milder forms of infection. In such cases, there is no immunization.
In the more severe and prolonged forms of the disease it is different. There is the formation of a specific adaptive response to combat this invader. That response is what makes up immunization.
Another problem, according to Moreno, is that in some cases an immunization can occur, but it is not lasting, this is what happens in the case of the influenza virus, for example. “The two mechanisms may be happening in parallel,” he explained.
see also
+ 5 benefits of intermittent fasting plus weight loss
+ Young man dies after 50-meter fall during Slackline Highline practice
+ Meet the phloeodes diabolicus “the indestructible beetle”
+ The trick to squeeze lemons becomes crazy on social networks
+ Woman pretends to be an FBI agent to get free food and goes to jail
+ The woman is run over by her own Range Rover and the widower says the gear button is the culprit; watch the video
+ Tender, chester and turkey: understand the difference between meats for Christmas dinner
+ The Digital Blue Zone in SP changes on the 16th; look how it looks
+ Study reveals the healthiest method of cooking rice
+ Can burping a lot be a health problem?
+ Shark is captured in MA with remains of missing youths in stomach
+ Cinema, sex and the city
+ A 6,500-year-old copper workshop discovered in the desert of Israel.
[ad_2]