Scientists alienate origins of monkeypox outbreaks

When the first cases of monkeypox were identified in early May, European health officials were baffled. The virus was not known to spread easily between people, let alone infect dozens – and soon hundreds – of young people.

The origins of fascism are now more clear. Genetic analysis indicates that although monkeypox virus spreads rapidly in the open, it has been spreading silently among people for years.

Health officials have already identified two versions of monkeypox among American patients, suggesting that there are at least two separate chains of transmission. Researchers in several countries have found cases with no known source of infection, indicating The spread of the undiscovered community. A research team argued last month that monkeypox did indeed infect crossed the threshold to a sustainable person-to-person transmission.

genetic Information Available now shown At some point in the past few years, the virus has gotten better at spreading among people, said Trevor Bedford, an evolutionary biologist at the Fred Hutchinson Cancer Research Center in Seattle.

“The genomes suggest that this occurred around 2018,” Dr. Bedford said.

If the virus adapts to include people as hosts, monkeypox outbreaks could become more frequent and more difficult to contain. This entails the risk of monkeypox being transmitted from infected people to animals – most likely rodents – in countries outside Africa, which have struggled with this problem for decades. The virus may persist in infected animals, intermittently causing new infections in humans.

“We can also transfer this back to animals that can spread disease within wildlife and back to humans,” said Sagan Friant, an anthropologist at Penn State University who has studied human-animal interactions in Nigeria for 15 years.

Dr Friant said the longer it takes to contain the virus, the higher the odds of it finding a new permanent home in humans or animals.

As of Wednesday, the United States had identified 156 cases in 23 states and the District of Columbia. The global tally has exceeded 3,400 confirmed cases, and another 3,500 cases are being evaluated, three times what it was two weeks ago.

There are eight countries in Africa informed More than 1,500 suspected cases and 72 deaths as of June 10, most of them in the Democratic Republic of the Congo.

Monkeypox is a large double-stranded DNA virus, approximately seven times the size of the coronavirus. DNA-based viruses can correct their mistakes when they copy their genetic material. They may only collect one or two mutations each year compared to 20 to 30 mutations of an RNA virus like the coronavirus.

But the monkeypox virus appears to have amassed an unexpectedly high number of mutations — nearly 50 compared to the version circulating in 2018, according to the Preliminary Analytics.

Of the 47 mutations identified in a single analysis, 42 bear a distinctive signature of an enzyme called Apobec3. First discovered by researchers studying HIV, this enzyme is called a host defense factor – an immune weapon that animals and people use to disarm viruses such as monkeypox.

The enzyme essentially forces viruses to make mistakes when they try to reproduce, causing them to self-destruct. Mice carry only one copy of this enzyme, while humans have seven. Dr Bedford said the rapid buildup of mutations, a feature of the enzyme since 2018, suggested monkeypox may have switched to people as hosts at that time.

It is unclear how mutations can change the virus. from 48 mutations set in Britain21 It may affect how the disease spreads, its severity and how well it responds to a treatment called tecovirimat, according to the UK’s Health Security Agency.

But because mutations introduced by the Apobec3 enzyme are intended to damage the virus, their quantity alone is not a concern, said Michael Malem, a virologist at King’s College London who discovered Apobec3 in 2002. The effect of the mutations is likely to be debilitating. Comparing the current version of the virus with samples from the past few years may help in understanding how it evolved, but this information is scarce. Nigeria did not have the ability to sequence genetic material until 2017.

Since then, scientists there have been analyzing sequences from about 50 cases of monkeypox, according to Dr. Evidayo Aditiva, director of the Nigeria Center for Disease Control. Without the specialized equipment or expertise needed for rapid analysis, he said, the scientists had not yet completed their work.

Although the researchers sent several requests for data from outside Nigeria, Dr. Adityva said they would wait to publish their work to prevent teams with more resources than their competition and to get credit.

“I’m all for sharing open data and all that,” he said. “The question is who benefits?”

Some experts have to caution for years That the eradication of smallpox in 1980 Leaving the world vulnerable to the broader family of poxviruses and increased the odds of monkeypox evolving to successful human nurse.

In West Africa, the incidence of monkeypox increased at least Twenty times as much since 1986. In African countries in general, “we suspect some under-reporting because there is relatively low awareness and possibly a lower risk of monkeypox,” said Dr. Aditieva. He added that Nigeria is ramping up its monitoring of monkeypox, and case numbers may rise as more people become aware of the virus.

Although there is a characteristic rash of monkeypox that appears on the palms of the hands and the soles of the feet, it is often Confused with chickenpox. Many men in the current outbreak have lesions on their genitals, but these can be confused with sexually transmitted infections such as syphilis. Gonorrhea and chlamydia.

Researchers in Italy and Germany I reported finding monkeypox DNA in semenBut it is not clear whether the virus spreads in this way or is only present in semen and vaginal secretions.

The prevalence of genital ulcers among young people has been observed at least once before. In 2017, Nigeria recorded 228 suspected monkeypox cases and 60 were confirmed. The virus spread Primarily among young people Those with ulcers in the genitals.

Britain’s experience shows how this can happen Tracking contacts can be complicated For a virus that may be transmitted through sexual contact, especially in cases where infected people have several unknown partners. In a preliminary analysis of a subset of cases, officials said they were able to obtain the names of fewer than a third of the 78 people whose sexual contacts were reported.

Many cases in Africa have been traced back to contact wild animals or use animal products to medical or cultural practices.

As deforestation and urbanization push people and animals closer together, more viruses may jump to the human host. The monkeypox virus is more likely to be transmitted to humans from rodents. There are about 2,000 species of rodents worldwide, making up 40 percent of all mammal species. The African cord squirrel is a prime candidate as the primary reservoir for monkeypox, but there are other contenders, including flower-striped rats, giant sack rats, rust-nose rats, and brush-tailed porcupines.

In a 2003 US outbreak, a shipment of bagged Gambian rats imported from Africa transmitted monkeypox to prairie dogs, which then infected 71 Americans. But officials did not find signs of the virus in animals in the United States once the wave of cases ended.

There is no guarantee that luck will last this time. “These ramifications are of other kinds, what that means and what the pathway is – it’s very unexpected,” said Dr. Malem. “It happens more and more.”