Those vaccinated for smallpox 40 yrs ago have immunity against monkeypox: Dr Yong
People who received a dose of smallpox vaccine 40 years ago still have immunity against monkeypox, Thailand’s top virologist Dr Yong Poovorawan said on Tuesday.
They had been given the vaccinia virus, which was originally understood to be cowpox, as a vaccine to boost immunity against smallpox, Yong explained.
“Smallpox is a DNA virus with similar genetic and structural characteristics, so it can protect people from other species as well,” he said.
Smallpox and monkeypox have an average incubation period of nine days, different from Covid-19’s three days, Yong noted.
He said that even though immunity against the disease with a long incubation period had dropped, the body is still able to stimulate defences to protect people from infection and from developing severe symptoms.
For example, only one human papillomavirus (HPV) vaccine jab can help effectively protect people from cervical cancer, thanks to HPV’s long incubation period, Yong pointed out.
“Hence, the immunity of people who received a smallpox vaccine jab a long time ago is unmeasurable,” he said.
People given this dose may have to receive only one shot of a new-generation vaccine to stimulate immunity against monkeypox, he added.
