How is smallpox spread? Things to know about transmission
UUntil recently, monkey pox It is rarely spread from person to person. In 2005, research announced a cluster of six cases in the Republic of the Congo as “the longest uninterrupted human chain of monkeypox to date.”
That has changed, to say the least. Up to present this year, More than 25,000 cases of monkeypox have been recorded over 83 countries — and human-to-human transmission is clearly happening on a massive scale.
How does monkeypox spread between humans? Research is ongoing and findings surrounding the transmission of smallpox in monkeys may develop over time. But here’s what the latest science suggests.
Most cases have been linked to infected animals
The first human case of monkeypox was identified in a baby living in the Democratic Republic of the Congo in 1970. according to the World Health Organization (WHO). Over the following decades, cases of the disease were quite rare and were often associated with contact with infected animals. America experienced a small outbreak in 2003with 47 cases in humans associated with prairie dog exposure.
Everything changed in 2017, when there was a rather large human outbreak start in Nigeria. Doctors there diagnosed cases of young men who had not had contact with infected animals and had lesions on their genitals, as NPR reported. Nigerian researchers published a 2019 study outbreaks and increased the likelihood of sexual transmission, but the theory gained little traction at the time. “People tend to close [onto] Study co-author Dr Dimie Ogoina, president of the Infectious Diseases Society of Nigeria, says what is the tradition, and the tradition holds that smallpox in monkeys is transmitted from animals to humans.
Most cases of smallpox in monkeys in the ongoing outbreak are related to sex
As the current outbreak shows, human-to-human transmission of smallpox has occurred — and sexual activity plays an important role.
“Currently, most transmission is happening in gay and gay sex networks, and Most transmission occurs through sexual contact or intimate contact“Joseph Osmundson, an assistant professor of clinical biology at New York University.
Ogoina says monkeypox is primarily spread between humans by close, skin-to-skin contact — especially with signs of blistering rash. Researchers are still studying whether people can be contagious asymptomatically, but individuals are considered to be contagious at least until their rash has completely healed and their skin is fresh. newly formed, based on US Centers for Disease Control and Prevention (CDC).
Research on the current outbreak, published in July in New England Journal of Medicine, found that, of the more than 500 cases of monkeypox across 16 countries diagnosed as of June, 95% were related to sexual activity and 98% were in men who were sexually active. same-sex sex. In July, WHO Director-General Tedros Adhanom Ghebreyesus advise men who have sex with men to temporarily reduce the number of their sexual partners to reduce their risk of contracting the disease.
Is monkeypox a sexually transmitted disease (STI)?
Any form of skin-to-skin contact — not just sexual activity — has the potential to spread smallpox in monkeys. Therefore, monkeypox is not considered a “traditional” sexually transmitted disease. based on Dr. Roy Gulick, head of the infectious disease division at Weill Cornell Medicine and NewYork-Presbyterian. CDC also speak Monkeypox is not considered a sexually transmitted disease.
Most cases in the current outbreak have been linked to male sexual activity, but Osmundson said the virus can also spread in places where there is a lot of non-sexual contact, such as like on sports teams, in spas or in college dorms.
Can you get monkeypox from surfaces?
Smallpox in monkeys can be contracted by contact with items, such as clothing or bedding, that have touched an infectious person’s rash. In 2018, a healthcare worker in the UK contracted monkeypox most likely after handling sick people’s bedding, according to a study.
Angela Rasmussen, a virologist at the University of Saskatchewan in Canada, says there is little evidence that frequent “random” contact spreads the virus. “You have to be exposed to all sorts of viruses to really get it,” she said. That can happen after sharing a bed or sharing a towel with an infected person, but is less likely after fleeting encounters like touching shared doorknobs, she said.
Müge Çevik, clinical lecturer in infectious diseases at the University of St. Scotland. “Every contact [doesn’t carry equal] risk,” she said. “People really need to know where to stay vigilant. Example: new reduction [sexual] A partner can be more helpful than wiping down the chair you’re sitting on in a coffee shop. “
Is smallpox in monkeys contagious?
Smallpox can be contracted in monkeys from contact with respiratory secretions from an infected person, but WHO says often requires close, long-term direct contact. According to the CDC, researchers are still studying how often that type of transmission occurs.
Scientists have demonstrated that it is possible, under specific experimental conditions, that monkeypox can be spread by aerosols, or that small particles can be suspended in the air – but so far, There is no solid evidence that that happens under real-world conditions outside of Rasmussen said in the lab. “This is mainly spread in communities of men who have sex with men, and it really shows that the main mode of transmission is prolonged, direct skin-to-skin contact,” she said. If airborne transmission were common, she said, we would likely see more cases in people of other demographic groups.
In the shadow of COVID-19, people are understandably concerned about monkeypox, which can be transmitted by aerosols. But “the epidemiology is very different,” says Rasmussen. “These are very different viruses.”
Can children get smallpox in monkeys?
More than 80 children around the world have been sick with the virus so far, largely the result of familial transmission. According to the CDC, a pregnant person can also transmit the virus to a fetus.
In the 1970s, monkeypox mainly affected young children – but by the 2010s the virus was diagnosed more frequently in adults, according to a new study. research published year PLOS Neglected Tropical Diseases in February. That was partly due to routine smallpox vaccinations (which also protects against smallpox in monkeys) ended when smallpox was eradicated, the study’s authors wrote. A few decades ago, only babies small enough were born after finishing smallpox vaccination. Now, a larger segment of the population is vulnerable.
The pediatric cases have raised concerns that schools and daycares could become hotspots for smallpox in monkeys. But Ogoina says that didn’t happen during the outbreak in Nigeria, which is a promising sign. “I’m not sure if that’s something we need to worry about,” he said. “But we need to be cautious and look for evidence.”
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