The first results of the genetic sequencing of monkey pox virus, which is being implemented in Portugal, surprised the researchers. All results already processed indicate an average of 50 mutations (nucleotide polymorphisms), which is sufficient to distinguish this virus from the previous outbreaks observed in 2018/2019 in African countries, Israel, Singapore and the United Kingdom.
“Comparing the genome now with what already exists, it is similar to the cases that were sequenced from 2017 to 2019, in Africa, Israel and the United Kingdom, but it has about 47 mutations compared to its predecessors, which is a large number. An unexpected type for this type of virus,” as says Camila Malta, a researcher in the Laboratory of Medical Investigations at Hospital das Clinicas, FMUSP (University of Medicine School of São Paulo) and Institute of Tropical Medicine.
The scientist draws attention to the fact that one or two mutations of this virus are usually observed every year.
“What I’ve seen now is that it seems to be developing faster. […] Almost all of the ten sequenced viruses already have a few – two or three – mutations between them, proving that the rate of evolution of this virus appears to be faster.”
One hypothesis that scientists have put forward to explain the disease’s rapid transmission and in places where there is no clear link is that the so-called orthopoxvirus has mutated, facilitating the disease’s further spread among humans.
Despite the surprise, Camilla points out that it is still not possible to confirm this hypothesis with available genome analyzes.
“It is still too early to tell, as the only more detailed analysis that has been done on these genomes has noted that most mutations appear to be neutral or harmful, i.e. not ‘good’ for the virus.”
The changes may be a response against infection.
“It may be the result of selective pressure from the host, trying to eliminate the virus. A certain enzyme, called APOBEC, acts in us as an antiviral, because it causes mutations in viruses as they multiply. These mutations have a specific pattern – and this is exactly the pattern found in smallpox mutations. monkeys [nome em inglês] From the outbreak now,” the biologist explains.
However, it is also possible that mutations have arisen over time without samples available for comparison. Another line of research is the virus that has accumulated many mutations in a short time (hyper-stimulated) as a result of the APOBEC enzyme.
He summarizes: “These mutations could indeed be the result of an attempt by the host to control the virus. And not the other way around, i.e. the adaptation of the virus to be more transmissible.”
Mutations in the pathogen that causes monkeypox are more difficult because it is a DNA virus. Unlike SARS-CoV-2, which causes Covid-19, it is RNA and changes faster.
Since the global eradication of conventional smallpox – announced in 1980 – monkeypox has emerged as the most common orthopoxvirus infection in humans.
In an interview last week, the head of the bioinformatics unit at the Department of Infectious Diseases at INSA (National Institute of Health Doctor Ricardo Jorge) in Portugal, Joao Paulo Gomez, said that the virus detected in the country is less aggressive than the one detected in the country. The type that is common in West Africa.
“In theory, it is evolving more than we expected. Eventually we will be able to realize that these genetic characteristics may be linked to greater transmissibility, and we still don’t know,” the researcher was quoted by Xinhua as saying.
Portugal is the third country in the world in the number of positive diagnoses, with 100 cases, after only Spain and England.
“The situation is rapidly evolving and WHO expects that there will be more cases identified as surveillance expands in non-endemic countries as well as in countries known to be endemic that have not reported cases recently,” the WHO said. In a statement issued on 29.
