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Numerous mutations – This is why the virus is successful
Status: 12:48 p.m | Reading time: 4 minutes
Why is monkeypox suddenly spreading? The virus is apparently mutating stronger and faster than previously thought. Astonishing insights into the development of the disease can be gained from the analysis of the mutations.
The current cases of monkeypox are causing great concern to authorities and scientists. So far, the disease, which currently affects young men in particular, has hardly spread outside of Africa. What has caused thousands of cases to appear in dozens of countries since May?
A new study in which the genome of monkeypox viruses was analyzed and compared could provide an answer to this question . Accordingly, the causative agent of the current outbreak has mutated surprisingly strongly. Compared to related viruses from 2018 and 2019, there are around 50 differences in the genome, writes a team from Portugal in the journal "Nature Medicine". This is about six to twelve times more than what would have been expected based on previous estimates for this type of pathogen.
The divergent branch could be a sign of accelerated evolution. The work is based on analyzes of Portuguese cases. So far, experts had spoken of a generally rather slow development with regard to this type of virus - especially in comparison with the frequent mutations of Sars-CoV-2.
The authors of the study suspect one or more imports from a country in which the virus is permanently present behind the current outbreak. Superspreader events and international travel then seemed to have fueled further spread.
"Our data provide additional evidence of ongoing viral evolution and possible adaptation to humans," writes the team led by João Paulo Gomes from the National Institute of Health Doutor Ricardo Jorge (INSA) in Lisbon.
The expert on the evolution of viruses, Richard Neher from the Biozentrum of the University of Basel, explained that
the mutation rate was "indeed surprisingly high". The mutations would have a very specific pattern. The authors suspected that enzymes of the human immune system are responsible for these changes in the genome.
Even within the current outbreak, we are seeing this accelerated mutation. The rate is roughly one mutation per genome per month - with some uncertainty," said Neher. Sars-CoV-2 has about two mutations per genome per month, but the genome is about seven times smaller. However, such comparisons of mutation rates are not very meaningful and say little about the relative evolutionary mutability of the viruses.
When asked whether the mutations made the current spread possible in the first place, the scientist explained that to his knowledge there was no evidence of this, but that it could not be ruled out. Most of the mutations would "probably have no dramatic effects".
However, other researchers see evidence that the virus has been circulating largely unnoticed for several years. According to evolutionary biologist Trevor Bedford, the data available so far suggests that the virus became more transmissible from person to person at some point during this period. "The genetic patterns indicate that this happened around 2018," the scientist from the Fred Hutchinson Cancer Research Center in Seattle told the New York Times.
The enzyme APOBEC3 , which was discovered during research into HIV , seems to play a special role here . The enzyme helps the immune system fight off certain viruses by forcing them to introduce serious errors into the genetic material, thus preventing them from multiplying.
The increased mutations associated with the enzyme since 2018 could indicate that monkeypox viruses switched to using humans as hosts, according to Trevor Bedford.
WHO chief is concerned
Around 5,000 monkeypox infections have been reported worldwide this year alone. In more than 40 countries outside of Africa, where the disease was practically unknown until May, there were 3,308 cases, according to current information from the US health authority CDC. According to statistics from the World Health Organization (WHO), there are also around 1,600 suspected or confirmed cases in eight African countries, many of which have known such outbreaks for years.
WHO chief Tedros Adhanom Ghebreyesus expressed his concern about the current development in an emergency committee in Geneva on Thursday: "Human-to-human transmission is ongoing and is likely to be underestimated." Most of the reported cases involve men who have sex with men .
According to Ghebreyesus, people with a compromised immune system, pregnant women and small children are at risk of serious illnesses if they become infected. "It is important that countries remain vigilant and strengthen their capacities to prevent spread."
Most cases outside of Africa were reported in 29 countries in the WHO European region: a total of 2746, as reported by the EU health authority ECDC and the Regional Office for Europe of the World Health Organization WHO in a joint analysis. As can be seen from the data, almost all of the confirmed cases are male. Around 44 percent of those affected were between 31 and 40 years old.
https://www.welt.de/wissenschaft/ar...tationen-Darum-ist-das-Virus-erfolgreich.html
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Study: Monkeypox virus mutates faster than previously thought
As of June 24, 2022, 1:21 p.m
A study on the first monkeypox genomes in Europe shows amazing results. The virus is a clearly new variant and is mutating faster than normal.
The analysis of the monkeypox virus is giving researchers more and more mysteries. The pathogen was actually considered very rare for a long time. As scientists have now found out in a study, the causative agents of the first major outbreak outside of Africa are a clear mutant, which, however, changes exceptionally quickly. This is what a working group led by João Paulo Gomes from the Portuguese National Health Institute writes in a study on the genome data that has been published in the scientific journal "Nature".
WHO emergency committee convened for monkeypox
"The strain of virus sequenced in May 2022 and associated with the current outbreak in Europe is a clearly distinct branch from the monkeypox viruses of the 2018/19 outbreak in African countries," the study said.
The results also pointed to mutations in an ongoing evolution in human-to-human transmission. According to the researchers, this "continued accelerated evolution" could also explain the increasing transmission of the strain in Europe
First transnational outbreak in spring 2022
Monkeypox is a rare infectious disease that spreads between different species, including from animals to humans. It is caused by the monkeypox virus (MPXV) from the orthopoxvirus genus (which also includes the smallpox virus). To date, monkeypox has been localized primarily in West and Central African countries, with rare reports of cases outside of these regions being associated with imports from these countries. Until spring 2022. For the first time, the monkeypox virus spread across countries - also in Europe. More than 2,500 confirmed cases have been confirmed worldwide. (as of June 18).
How did the scientists come to accept the rapid mutation?
To study how the Spring 2022 outbreak began, João Paulo Gomes and colleagues reconstructed the genome sequences of the monkeypox virus (MPXV), which has been linked to the outbreak. Their conclusion: The MPXV from 2022 belongs to MPXV clone 3 and probably has a single origin. It differs from the related viruses from 2018 and 2019 by having about 50 single nucleotide polymorphisms (the occurrence of multiple gene variants), or genetic variations -- more than are usually expected for orthopoxviruses. Such a divergent branch could represent ongoing accelerated evolution, the authors believe.
Mutations during human-to-human transmission
In further analyses, the scientists actually found indications of ongoing evolution. During the human-to-human transmission of the current outbreak, they analyzed 15 single nucleotide polymorphisms, minor variants and the loss of a stretch of DNA (technical term gene deletions).
The monkeypox genome was first sequenced in 2018
Researchers first sequenced the genome, originally found in countries in West and Central Africa, in 2018 after previously appearing in Singapore, Israel, Nigeria and the UK. At that time, however, the virus was still associated with importation from African countries. The monkeypox outbreak in spring 2022 revealed for the first time a large number of diseases in Europe and also in Germany, which, as the researchers have just discovered, can be transmitted directly and also mutate from person to person. The current virus differs from the monkeypox virus of 2018 at a total of 47 points in the genome.
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https://www.mdr.de/wissen/mensch-al...-schnelle-evolution-viele-mutationen-100.html