More than 50 cases of monkeypox, a rare infectious disease that causes flu-like symptoms and skin rashes and body lesions, have been reported in at least 16 countries since May 13. according to the World Health Organization. The United States had its first confirmed case last week in Massachusetts, followed by six probable cases in New York, Florida, Utahand washington state. At the time of this report, there is also a suspected case in California.
The unprecedented spread of this disease may seem grim, but that doesn’t mean we’re unprepared. In an article published on Tuesday in The Lancet Infectious Diseases journal, researchers in the UK believe we may have an antiviral miracle solution originally developed to fight smallpox, a cousin of monkeypox. The article also highlights what scientists know about how this infection passes from person to person, highlighting growing evidence that it is sexually transmitted.
“The document is reassuring,” Dr. Brian Garibaldi, medical director of the biocontainment unit at Johns Hopkins who was not involved in the study, told The Daily Beast. “We have some experience providing care for patients who have been infected with monkeypox outside of traditional endemic areas. And it highlights the fact that we still have a lot to learn about how to use therapies designed for smallpox to treat others. [smallpox-related] virus.
Monkeypox is not a new virus; it was first discovered in monkeys kept for research in 1958. Researchers believe that rodents and other small mammals are the primary animal hosts that keep the virus alive and circulating. The first documented outbreak of monkeypox in humans was in 1970. Since then, there have been occasional outbreaks in West and Central Africa, with few rarer cases elsewhere in the world. (The last human outbreak of monkeypox in the United States occurred in 2003.)
While obviously alarming, these outbreaks provide scientists and clinicians with unique opportunities to study and better understand the disease. In The Lancet article, researchers looked at cases of monkeypox in the UK from August 2018 to September 2021 and identified seven patients who received two antiviral drugs used to treat smallpox: brincidofovir and tecovirimat. Although both of these drugs are approved for use in the United States in special circumstances such as bioterrorism cases involving smallpox, their effectiveness has only been tested in animals. (It is unethical to intentionally infect humans with smallpox for the purpose of a clinical trial, Dr. Stanley Deresinski, an infectious disease specialist at Stanford University who has no participated in the study.)
Of the two drugs, tecovirimat appears to be the clear winner. Three monkeypox patients who were taking brincidofovir all developed elevated liver enzymes, which is a sign that the liver is in distress or destroyed. But the one patient on tecovirimat seemed to be tolerating the antiviral drug quite well and spent just 10 days in hospital compared to the others who spent up to two to three weeks or even more than a month.
While these results suggest we might want to add tecomirivat to our monkeypox-fighting arsenal, experts like Dr. Rebecca Wurtz, an infectious disease specialist and public health researcher at the University of Minnesota, have said that we were still in the very early stages where we can’t be too quick to jump to conclusions.
“We had so little experience [with these drugs] because we didn’t need to use them for what they were basically developed for, which was smallpox,” Wurtz, who was not involved in the study, told The Daily Beast. “We haven’t used them clinically for monkeypox because most people resolve the infection on their own, so we didn’t need to use them as potential treatments.”
Wurtz pointed out that it’s not even entirely clear whether tecovirimat was integral to this patient’s speedy recovery.
“It turned out that she had a relatively milder infection acquired from her daughter and although she seemed to get better, was that just because everyone with monkeypox eventually gets better or was it actually attributable antiviral?” Wurtz said.
Wurtz and Deresinski think the antiviral drug could instead benefit immunocompromised people, who can be hit hardest by monkeypox because their immune systems aren’t equipped to clear the infection naturally.
The Lancet The study also provides insight into exactly how the virus is transmitted between humans. The prevailing thought is that it takes close intimate contact through infected lesions or bodily fluids to transition from human to human. Many patients in the study appeared to have contracted the virus through sexual contact as they had skin lesions in the groin area. In the past, exposure to infected animals was thought to play an important role in transmitting the virus, so the sexual route of transmission has been underestimated, Wurtz said.
Despite the growing number of cases, monkeypox should not be considered an imminent threat anytime soon, even if the development of antivirals needs more work. Existing smallpox vaccines work against monkeypox. Monkeypox is unlikely to spread wildly, let alone COVID-19.
“I don’t think it will be a widespread problem,” Garibaldi said. “I think we are going to see more cases – there are people who have already been exposed who could develop an infection in the future. But now that we recognize it exists and understand that we need to be on the lookout, we can effectively isolate people. I think we are going to be able to prevent this from becoming a major epidemic.