How is monkeypox spread?what scientists know

As monkeypox cases continue to surge worldwide, researchers are learning more about how the disease spreads. Early predictions of transmission by repeated skin-to-skin contact between individuals are largely supported.

“When you put all these studies together, you see clinical similarities everywhere, which is also surprising,” says Oriol, an infectious disease researcher at the Germans Trias y Puyol University Hospital in Barcelona, ​​Spain. says Mitjà.of recent research in lancet¹That’s because the pattern of symptoms and spread is different from what researchers have observed in western and central Africa, where the monkeypox virus is endemic. Has caused isolated and sustained outbreaks for decades.

Since early May, monkeypox has spread to more than 90 countries, infecting more than 32,000 people, nearly a third of them in the United States.The rapid spread of the virus has prompted the World Health Organization to issue the highest public health alert July 23rd. US President Joe Biden followed suit by declaring a US public health emergency on August 4.

Some women and children have been infected since May, but so far most cases have been in men who have sex with men (MSM), especially men with multiple sexual partners or having anonymous sex. Mitjà says the virus probably spread efficiently by taking advantage of the dense sexual networks of the MSM community. Increased chances of infecting a group. Scientists warn that it can establish viral reservoirs that can repeatedly infect humans.

‘Full of viruses’

People with monkeypox may have flu-like symptoms, enlarged lymph nodes, and characteristic fluid-filled lesions on the skin. Some researchers have suggested that the monkeypox virus could be spread via respiratory droplets or airborne particles like SARS-CoV-2, but Mitjà and his colleagues reported that samples taken from skin lesions when was diagnosed contained more viral DNA.do them out of the throat¹The lesions appear relatively “viral-filled,” says Boghuma Titanji, an infectious disease physician at Emory University in Atlanta, Georgia.

some research^2,3indicating that few people contract the disease from infected family members who have no sexual contact, including those from Mitjà. This suggests that it is not a common route of transmission, says Titanzi.

Detailed data about how a person’s viral load changes over time is still lacking, says Jessica Justman, an infectious disease specialist at Columbia University in New York City. His colleagues did not detect much viral DNA in samples taken from people’s throats early in the infection, but they may have had higher virus levels if they had taken them later or earlier. she says. Such data, which the team is currently collecting in follow-up studies, will allow public health officials to provide better isolation and treatment guidance for infected people.

talk about sex

It is not yet known whether monkeypox is absolutely sexually transmitted, that is, whether it is transmitted from person to person through blood, semen, or other bodily fluids during sex. , monkeypox virus DNA has been found to be present in human semen for several weeks after infection.^2,3In one study, infectious virus was isolated from the semen of one individual six days after the onset of symptoms.^Four.

Even if the virus can be transmitted sexually, how much larger is this mode of transmission compared to simple human-to-skin-to-skin contact or inhalation of respiratory particles? It is unknown whether it is fulfilled. This also happens during sex. If other studies find infectious virus in semen, it will be important to understand how long it can persist in bodily fluids. It can persist in semen for months, complicating efforts to prevent epidemics.Until researchers know more, the UK Health Security Agency Recommend continued use of condoms 8 weeks after infection

Mitja and his colleagues found that in the people they examined, more lesions in the mouth and throat were associated with oral sex, and more lesions in and around the anus were associated with anally receptive sex. Given all these findings, Titanjee said it was important for public health officials not to hesitate to talk about sex in their guidance and to be clear about the types of protection available. It says there is

More data from rigorously designed studies just can’t come fast enough, says Justman. Some researchers are already concerned that the outbreak has passed the point of containment. Inadequate vaccine stockpiles When Inaccessible antiviral treatmenteven as inadequate testingFunding and motivation to study monkeypox are limited compared to COVID-19, she says. “We don’t have ‘Operation Warp Speed,'” she adds.