Recent headlines about the sudden emergence of an unusual disease, spreading case by case across countries and continents, may, for some, evoke memories of the early 2020s.
But monkeypox is not COVID-19 — in a good way.
Health officials around the world have turned their attention to a new outbreak of smallpox, a virus typically found in central and western Africa that has appeared in Europe and the US in recent weeks — even in people who have never traveled to Africa.
But experts say that while it is important for public health officials to keep an eye on monkeypox, it is extremely unlikely that the virus will escalate into an uncontrolled worldwide pandemic in the same way as COVID-19.
“Let’s just say up front that smallpox and COVID are not the same disease,” said Dr. Rosamund Lewis, head of the Smallpox Secretariat at the World Health Organization, in a public question-and-answer session on Monday.
For starters, monkeypox spreads much less easily than COVID-19. Scientists have studied monkeypox since it was discovered in humans more than 50 years ago. And its similarities to smallpox mean it can be fought in many of the same ways.
As a result, scientists are already familiar with how monkeypox spreads, how it presents itself, and how to treat and contain it – giving health officials a much greater advantage in containing it.
Here are some of the other ways the public health approach to monkeypox differs from COVID-19:
Scientists already know how it spreads and it’s different from COVID
Monkeypox normally requires very close contact to spread – most often skin-to-skin contact or prolonged physical contact with clothing or bedding that has been worn by an infected person.
On the other hand, COVID-19 spreads quickly and easily. The coronavirus can spread simply by talking to another person, sharing a room, or, in rare cases, inside a room that an infected person was previously in.
“Transmission is actually happening by close physical contact, skin-to-skin contact. It’s quite different from COVID in that sense,” said Dr. Maria Van Kerkhove, an infectious disease epidemiologist at the WHO.
The classic symptom of monkeypox is a rash that usually starts on the face and then spreads to a person’s limbs or other parts of the body.
“The incubation from the time of exposure to the appearance of lesions is five days to about 21 days, so it can be quite long,” said Dr. Boghuma Kabisen Titanji, an infectious disease physician and virologist at Emory University in Atlanta.
The current outbreak has seen a few different patterns, experts say — particularly, that the rash starts in the genital area first and may not spread throughout the body.
Either way, experts say, it’s usually through physical contact with this rash that the virus spreads.
“It’s not a situation where if you’re passing someone at the supermarket, they’re at risk of monkeypox,” said Dr. Jennifer McQuiston of the Centers for Disease Control and Prevention at a briefing on Monday.
People most likely to be at risk are close personal contacts of an infected person, such as family members or healthcare professionals who may have treated them, she said.
“We’ve seen over the years that often the best way to handle cases is to keep patients isolated so they can’t spread the virus to close family members and loved ones, and to proactively follow up with those a patient comes into contact with so they can observe. symptoms,” McQuiston said.
With this version of the virus, people usually recover in two to four weeks, the scientists found, and the fatality rate is less than 1%.
Monkeypox is less contagious than COVID-19
One factor that helped COVID-19 spread rapidly around the world was that it was very contagious. This is even more true for the variants that emerged in the last year.
Epidemiologists point to the R0 value of a disease – the average number of people to whom you would expect an infected person to transmit the disease.
For a disease outbreak to grow, the R0 must be greater than 1. For the original version of COVID-19, the number was between 2 and 3. For the omicron variant, that number is around 8, according to a recent study .
While the recent spread of smallpox cases is alarming, the virus is far less contagious than COVID-19, according to Jo Walker, an epidemiologist at the Yale School of Public Health.
“Most of the previous outbreak estimates had an R0 of less than one. With that, you can have clusters of cases, even outbreaks, but they will eventually die on their own,” they said. “It could spread between humans, but not very efficiently in a way that it could sustain itself without constantly being reintroduced from animal populations.”
This is a big reason why public health officials, including the WHO, are expressing confidence that monkeypox cases will not skyrocket. “This is a manageable situation,” Van Kerkhove said Monday at the public session.
As smallpox is closely related to smallpox, vaccines already exist
Monkeypox and smallpox are both members of the Orthopox virus family. Smallpox, which once killed millions of people every year, was eradicated in 1980 by a successful worldwide vaccine campaign.
The smallpox vaccine is about 85% effective against smallpox, says the WHO, although that effectiveness declines over time.
“These viruses are closely related to each other, and we now have the benefit of all these years of research, diagnostics and treatments and vaccines that will be applied to the situation now,” said WHO’s Lewis.
Some countries, including the US, keep smallpox vaccines in strategic reserve in case the virus re-emerges. Now, they can be used to contain an outbreak of monkey pox.
The FDA has two vaccines already approved for use against smallpox.
One, a two-dose vaccine called Jynneos, has also been approved for use against monkeypox. About 1,000 doses are available in the Strategic National Stockpile, the CDC says, and the company will provide more in the coming months.
“We are already working to ensure a sufficient supply of effective treatments and vaccines to prevent those exposed from contracting monkeypox and to treat affected people,” Raj Panjabi, of the White House pandemic office, told NPR in an interview.