Hélène is right to ask the question, as these viruses are so similar. Both orthopoxviruses, they have a “clinical picture” similar, explains WHO on its website. That is why “several observational studies” demonstrated that prior vaccination against smallpox “was about 85% effective” against monkeypox, says the UN public health organization.
In a study published in 1987 (three years after the end of the last reminders), a team of researchers analyzed the clinical data of 282 patients with monkeypox in Zaire. And, according to their observations, “symptoms, signs, and disease course in patients who had been vaccinated against smallpox differed significantly from those in unvaccinated subjects”. “No deaths occurred in vaccinated patients”, said the researchers.
If there is no “specific” vaccine against the disease which has so far affected 16 people in Francethe smallpox vaccine is therefore “very effective in preventing monkeypox as well”, summed up the WHO.