What are the challenges in the fight against monkeypox?

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On May 12, Nesli Basgoz, an infectious disease physician at Massachusetts General Hospital, encountered a 31-year-old patient with troubling symptoms. After a trip to Canada, the man noticed itchy bumps around his genitals; a few days later he had a fever, swollen lymph nodes and profuse sweating. He had been sexually active during his trip, so Basgoz considered gonorrhea, syphilis, herpes, and HIV. None seemed to match his symptoms. She was given antibiotics and antivirals, but small fluid-filled blisters broke out on her arms and legs, and ulcers near her rectum, as well as inflammation inside, became so painful that he had trouble sitting up and sleeping. Basgoz contacted the state health department, which said it had not received any reports of similar illnesses.

At the hospital, Basgoz saw the man twice a day. One afternoon, she noticed distinctive dimples had formed in the center of the blisters. The next morning, she woke up before five o’clock with a hunch and started scouring the internet for information on orthopoxvirus, a genus of virus that can move between animal species, and which includes smallpox. . The UK, she learned, had recently issued a public health notice describing four men who had been diagnosed with monkeypox. “I had this sinking feeling,” Basgoz told me. “I knew there would be a lot of implications for a lot of people.” The patient was transferred to the special pathogen unit of the hospital. To confirm the diagnosis, she sent a sample on a circuitous trip, first to the state public health laboratory and then to the Centers for Disease Control and Prevention.

Doctors spend thousands of hours honing the skill of pattern recognition, matching signs and symptoms to conditions and treatments. As I learned during my medical residency at Mass General, Basgoz is a legendary practitioner of Bayesian reasoning: she starts from a set of assumptions, or “a prioris”, and updates them as she goes. as new information emerges. She makes lists of medical conditions that could explain a patient’s symptoms, and as she learns of lab tests, examinations, and attempts to treat an infection, she adds and subtracts from the list, moving plausible conditions up and improbable ones down. “When all that doesn’t give you an answer, you have to ask yourself, ‘Could this be a new agent or a new route of transmission?’ “Basgoz told me.

His experience with monkeypox also illustrates how medical knowledge is changing. Monkeypox has traditionally been understood as a two-stage disease, in which, a week or two after exposure, a person develops flu-like symptoms and then a generalized rash; within a few weeks, the blisters usually cover and heal, and the patient is no longer considered infectious. But the current outbreak has tested medical textbooks. Some patients, including the man treated with Basgoz, developed symptoms just days after exposure. It becomes clear that monkeypox may cause a rash before causing a fever, and the lesions may be few or confined to the genital areas. “The guidelines are based on what we’ve seen in the past,” Basgoz said. “When you’re dealing with something new, you have to keep an open mind.” As physicians share what they learn — at conferences, on Twitter, in Google Docs, preprints, and journals — their observations become the patterns others watch.

More than eleven thousand cases of monkeypox have now been reported in dozens of countries, including more than fourteen hundred in the United States. In Europe, cases have more than tripled in recent weeks. Official figures likely underestimate the true number of infections, due to inadequate testing and a lack of public awareness of the disease. In late June, the World Health Organization identified the outbreak as an “evolving health threat”, its second highest level of alert. Next week, the agency will reconvene its emergency committee and could declare monkeypox a global health emergency.

Monkeypox is unlikely to cause a nationwide pandemic. covid-19. The virus is much more lenient than the coronavirus – less transmissible, easily controlled by existing vaccines. But if we don’t act quickly, forcefully and globally, monkeypox could take hold permanently in a number of countries. It could become a regular scourge facing health care providers and public health systems; each year, the virus can inflict painful, sometimes scarring lesions on several thousand people, and it is likely to prove fatal for some. With an aggressive and coordinated public health campaign, we have the opportunity to learn from the mistakes of the past and avoid such a future.

The virus we call monkeypox was first identified in 1958 by Danish scientists studying primates in a laboratory, but ‘monkeypox’ is a misnomer because monkeys are not its natural reservoir. The virus primarily circulates among rodents such as dormice, rope squirrels and pouch rats. In 1970, a nine-year-old boy in the Democratic Republic of the Congo became the first known person to be infected, and for decades the disease was confined mainly to central and western Africa, where it spread among hunters and other people who handled bushmeat, suffered animal bites or came into contact with contaminated objects. Even as African countries warned of outbreaks and asked for help in containing them, the virus was mostly overlooked by the global community.

This isn’t the first time the United States has experienced an outbreak. In 2003, a distributor of unusual pets in Texas imported hundreds of rodents, including giant pouch rats, from Ghana. Some were sent to a distributor in Illinois, where they were housed alongside prairie dogs. Seventy-one people across the Midwest, the majority of whom had direct contact with prairie dogs, were infected. Fortunately, there were no fatalities; the United States has banned the importation of giant pouch rats.

Monkeypox comes in two flavors, or clades. The clade that predominates in Central Africa is more lethal, with a reported case fatality rate as high as 11%. (This rate has declined somewhat in recent years, and the absolute number of reported deaths has been relatively low, in the hundreds.) The West African clade, the one now circulating globally, is less severe. Yet before the current outbreak, even this version had a reported fatality rate of almost 4%, according to a recent study conducted by Bavarian Nordic, a Danish monkeypox vaccine manufacturer.

Most deaths occur in young children or immunocompromised people, and since January seventy-three monkeypox-related deaths have been reported in Africa. Outside the continent, however, there has not been a single confirmed death from monkeypox and hospitalizations have been rare. We don’t know what explains this. Perhaps the virus has evolved or is spreading in new ways, or perhaps those infected around the world differ in age or health status from those who have died from it. Maybe the different outcomes are the result of inequities in the health care infrastructure, or maybe they’re the result of something else entirely.

The virus is mainly spread by close contact with an infected person’s skin, bedding, towels or clothing. This makes sex a particularly effective mode of transmission; the current epidemic has primarily affected men who have sex with men, but there is little reason to believe that it will not affect other groups. (Although the virus is sometimes present in semen and other bodily fluids, it is not known whether it can be transmitted through them.) To a lesser extent, monkeypox can be spread through respiratory droplets produced when people cough or sneeze, but it does not appear to linger in the air or transmit effectively over long distances, and it is not thought to spread until people develop symptoms.

In most people, the symptoms of monkeypox can be treated with skin care and pain medication. In severe cases, doctors may administer tecovirimat, or Tpoxx, an antiviral drug that became the first treatment approved by the Food and Drug Administration to treat smallpox, in 2018, or brincidofovir, which was approved in 2021. Two vaccines are also thought to be effective. An older vaccine, CAPA2000, has been around in one form or another for nearly a century, and the US National Strategic Stockpile comprises a few hundred million doses. But CAPA2000, which is administered by an unusual technique that involves puncturing the skin multiple times, carries a risk of serious side effects, especially for people with heart disease and immune disorders. Bavarian Nordic’s new vaccine, Jynneos, was approved in 2019 and is much safer. The vaccine is given in two doses, 28 days apart. According to the CDC, a first dose given within four days of exposure can completely prevent infection, while a dose within two weeks can reduce symptoms.

Ideally, anyone who has known or probable exposure to the virus, or who feels they are at high risk of contracting the disease, would have access to rapid and convenient testing through primary care providers, health clinics emergency care, community health centers and mobile testing sites. Those who are confirmed carriers of the virus, or who simply want to take precautions, would receive a free, safe and highly effective vaccine. In a strategy known as ring vaccination, close contacts of people who test positive would be notified and offered vaccination, as would contacts of those contacts. We know it works, that’s how we eradicated smallpox.

But the supply of Jynneos vaccine is limited. Last week, the Department of Health and Human Services distributed only about fifty-six thousand doses; the agency now says it has distributed a hundred thousand more. For now, public health officials generally recommend the vaccine only to people who have had a confirmed or suspected exposure to monkeypox, or who have had multiple recent sexual partners in areas where the virus is spreading. Even for these groups, getting vaccinated hasn’t always been easy: Health departments in New York, Atlanta and San Francisco were quickly overwhelmed when they began offering monkeypox vaccines.

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