More than two years into the COVID-19 pandemic, a new infectious disease outbreak – monkeypox – is causing concern in Massachusetts and around the world. Jewish infectious disease doctors in the Boston area are urging the public to stay calm but vigilant.
Although the name of the virus comes from laboratory monkeys in Copenhagen, it is actually spread through rodents, who can then pass it onto other animals and humans. In 2003, a monkeypox outbreak in the western United States spread through pet prairie dogs. According to the Centers for Disease Control and Prevention, the pets were infected after being housed near small mammals from Ghana that were imported to Texas.
Monkeypox causes flu-like symptoms, swollen lymph nodes, and skin lesions.
Dr. Shira Doron, hospital epidemiologist and antimicrobial steward at Tufts Medical Center, said that it would “not be a good thing if monkeypox became entrenched in an animal residing in the U.S.,” adding this represented an unlikely but dangerous scenario.
One feature of the outbreak was the reappearance of smallpox in news headlines – in this case, the news that smallpox vaccines are being used against monkeypox. Antiviral drugs also exist to treat monkeypox.
“It’s believed that people who have previously received the smallpox vaccine, who are old enough to have been vaccinated against smallpox before the vaccine stopped and smallpox was declared eradicated, probably have some immunity or cross-immunity against monkeypox,” said Dr. Daniel Kuritzkes, chief of the Division of Infectious Diseases at Brigham and Women’s Hospital.
“The newer vaccines, which are different from the original smallpox vaccine but approved as smallpox vaccines, are effective against monkeypox and can be used to protect people, high-risk contacts who had very close contact with an index case of monkeypox,” Kuritzkes said. “Because the risk of person-to-person transmission is so low, there’s not a huge reason to be vaccinating people, except in very unusual circumstances.”
For the general public, Doron said, monkeypox is “not something to panic over,” but added that people should be “careful not to expose themselves to monkeypox. You should be alert to signs and symptoms in yourself and people you have close contact with.”
Asked whether the virus is airborne, doctors gave qualified responses.
“Yes, but only close and prolonged contact, not in the way chickenpox or measles or COVID-19 are airborne, where brief exposure to shared air may put you at risk,” Kuritzkes said.
Citing the CDC, he said that monkeypox spreads through “close contact for several hours, contact within six feet for several hours.
It can be spread by respiratory droplets from people who are physically quite close to each other, not somebody who happens to be in the same room.”
“It’s not considered classically airborne, the way that measles, tuberculosis, even chicken pox [are],” Doron said.
Monkeypox has an incubation period of up to 21 days.
“It starts very much like a lot of other viruses,” Kuritzkes said. “You can have a fever, muscle aches and pains, [and] not feel well.”
As it progresses, its symptoms include swollen lymph nodes and a rash featuring lesions, as well as pustules that turn into scabs.
“You’re contagious until the scabs fall off and new skin grows underneath,” Doron said. “There’s a long period of infection and a long period of contagion.”
The first monkeypox case in the U.S. was diagnosed by Dr. Nesli Basgoz last month at Massachusetts General Hospital.
“An infectious disease doctor heard all the news reports of monkeypox infections in other parts of the world, outside where you typically see it in Africa,” Doron said. “It made the list of things she decided to consider.”
Since then, around 200 people who came into close contact with the patient at MGH have been examined.
“There is not real concern that any of those people are at high risk for any monkeypox,” Kuritzkes said.
Overall, Kuritzkes said, “there has been an outbreak in Europe, and it is likely that cases now being seen in the U.S. are linked to the ongoing outbreak in Europe.”
The MGH patient had recently traveled to Canada, where an outbreak subsequently occurred as well. The bulk of cases this year have occurred in Africa, with nearly 15,000 to date. According to the World Health Organization, 780 laboratory-confirmed cases have been recorded outside Africa as of June 2.
“In the developed world – the Americas, Europe, the Middle East – I don’t think it’s a big concern,” Kuritzkes said. “It’s a slightly bigger concern right now for the LGBTQ community. It appears to have been amplified in the community, probably due to a couple of big events that kind of created an opportunity for spread.”
However, she said, monkeypox can be spread between “any two people who have any kind of close contact. We will increasingly see cases outside of the LGBTQ community. It just happened to have started there.”