Monkeypox vaccines are now available to some health care workers treating infected people.
“I am pleased to report that even with the first case in Boston at Massachusetts General Hospital, our colleagues across government were able to bring vaccines to this hospital. And just yesterday they already started offering the vaccines to healthcare workers who were exposed,” said Dr. Raj Panjabi, who is leading the White House’s monkeypox response, told CNN’s Laura Coates Monday night.
“The first part is identifying those infected and isolating them and making sure they get the care they need,” Panjabi said. “The second part is making sure we vaccinate those who have been exposed to the infected people. If we keep doing that — and that’s our approach in the White House and across the administration — then we have a better chance of ending this outbreak.”
A senior Biden administration official said Tuesday that generally small groups of people who have been exposed to a symptomatic monkeypox patient could be offered a vaccine — but this is not a mass vaccination effort.
“Because the monkeypox virus is closely related to the virus that causes smallpox, the smallpox vaccine can protect people from monkeypox,” according to the US Centers for Disease Control and Prevention website. “Smallpox and monkeypox vaccines are effective in protecting humans from monkeypox when given prior to exposure to monkeypox. Experts also believe that vaccination after exposure to monkeypox may help prevent or mitigate the disease.”
Scientists have known for years that smallpox vaccines can also be effective in preventing monkeypox. The variola virus, which causes smallpox, and the monkeypox virus belong to the same family.
“The viruses are from the same virus family, and what we’ve seen in previous monkeypox outbreaks is that exposure to vaccination in people with monkeypox aborts or weakens the infection,” said Dr. Amesh Adalja, senior researcher at the Johns Hopkins Center for Health Security at the Bloomberg School of Public Health.
However, do not expect a large-scale rollout of vaccines.
“I think that in contacts of cases we have to use vaccinations. Not everyone lines up here and gets vaccinated,” said Adalja about the current outbreak. “That will be crucial in stopping cases.”
What vaccines might work against monkeypox?
The senior administration official said Tuesday there was enough vaccine to cover the current level of cases in the United States.
“Right now we have over 1,000 cans of [Jynneos] available and we expect this level to increase very rapidly in the coming weeks as the company makes more doses available to us,” Dr Zoonotic Infectious Diseases said Monday.
Another vaccine called ACAM2000 is approved in the United States to prevent smallpox. Although the vaccine could be used to prevent monkeypox, it is not approved for that purpose.
The United States has more than 100 million doses of ACAM2000, McQuiston said.
“ACAM2000 is an older-generation smallpox vaccine that has some potential significant side effects,” she said. “So a decision to go that far would have to be seriously discussed.”
ACAM2000 is a live vaccine – and once injected, a lesion will develop at that site. Because the virus grows at the site of the lesion, it can spread to other parts of the body or even to other people, according to the CDC, so people receiving ACAM2000 “must take precautions” to prevent spread.
Who should be vaccinated against monkeypox?
Most people are not vaccinated against monkeypox. It is based on direct exposure.
Amid the global outbreak, officials at the World Health Organization plan to make recommendations on who should prioritize smallpox vaccination to reduce risk of monkeypox.
“It’s not something that everyone needs. It’s a virus that spreads between people who come into close contact with those who are cases,” said Van Kerkhove. “We really need to discuss evidence-based use of these interventions, access and equity.”
Andy Seale, policy adviser to the WHO Division for Global HIV, Hepatitis and STI Programmes, added that vaccination should be considered for countries where monkeypox is endemic, i.e. West and Central Africa.
“Communities are already telling us, ‘If we do this right, if we contain this, if we get the right to access the outbreak, we have to do the same for the endemic countries,'” Seale said.
Can someone be vaccinated after being exposed to monkeypox?
“That’s the norm. We don’t usually vaccinate everyone beforehand. We use vaccination as post-exposure prophylaxis,” Adalja said.
“Because monkeypox has a long incubation period, just like smallpox – monkeypox is about 12 days on average – you can go into an exposed person with a vaccine and it will stop the infection,” he said. “Or if you get an infection, maybe it comes on very late or late in the incubation period, it makes the infection less severe.”
But the sooner an exposed person gets the vaccine, the better. The CDC recommends giving the vaccine within four days of exposure to help prevent disease. When given between four and 14 days of exposure, the vaccine can relieve symptoms but may not prevent the disease itself.
Overall, people who have been exposed to the monkeypox virus and have not been vaccinated in the past three years should consider getting vaccinated, the CDC says.
Does a smallpox vaccine protect against monkeypox?
There is likely a “residual” protection against monkeypox for adults who were vaccinated against smallpox as children, Adalja said, but it may not be complete protection.
“The smallpox vaccination program ended in the United States in the 1970s. If someone is in the US military and was vaccinated last year, I’m sure they will be fully protected,” Adalja said. “But people who were vaccinated as children in the days when smallpox was a routine childhood vaccination may have some residual immunity.”
The senior Biden administration official said Tuesday that theoretically there is some protection from a previous smallpox vaccination, but there is no good evidence of how much protection — and that protection may wane over time.
Has the monkeypox virus changed with this outbreak?
The official said that nothing appeared to have changed in the biology of the monkeypox virus and that the general public still had a very small chance of contracting it.
WHO officials have found no evidence that the monkeypox virus changes or mutates in this outbreak. Therefore, there is no evidence that the approved vaccines are not effective against the virus currently circulating.
“It’s a very stable virus. So we have no evidence yet that there is a mutation in the virus itself,” said Rosamund Lewis, head of the smallpox secretariat of the WHO emergency response program, during Monday’s Q&A.
“We’re starting to gather that information,” Lewis added. “We will convene our groups of virologists and other experts who will discuss this very question based on the sequence of the genome of some of the detected cases.”
That’s a “key question” to answer, said Dr. Daniel Rhoads, co-chair of the College of American Pathologists Committee on Microbiology.
“Has something changed about the biology, or is this just an unusual situation that has never happened before, or we didn’t recognize it before?” I think it’s always a key question when the geography changes for these endemic diseases,” he told Rhoads, a pathologist at the Cleveland Clinic in Ohio.
“Whenever we see a new infection, or an infection that’s being transmitted in a seemingly new way, I always ask myself, is this just something we didn’t realize before that has always been there? Or is this an actual biological change, which would be due to a mutation in the virus? I don’t know,” Rhoads said.
“I suspect once they sequence the virus that’s causing the current outbreak they can compare it to known sequences and then hopefully we’ll have some insight as to whether or not it’s the same old monkeypox, if there’s anything.” , which appears to be different.”