To try to understand why monkeypox is currently spreading outside Africa, a continent where it is endemic in several countries, let’s go back a little in time, just after the cessation of anti-smallpox vaccination where populations in contact with monkeypox virus were left unprotected.
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[EN VIDÉO] What are the differences between bacteria and viruses? They are microbes. They are very small and they are quite easily confused. However, bacteria and viruses are two very different things. And to fight effectively against those that cause disease, it is better to identify them clearly.
On May 8, 1980, on the occasion of the 33e World Health Assembly, smallpox is officially declared extinct : “ All the peoples of the world are now free from smallpox. This is the result of a campaign of vaccination conducted for 10 years by theWHO, during which half a billion smallpox doses were distributed worldwide. Thus disappeared a disease known since Antiquity, fatal in 30% of cases and responsible for 300 million deaths during the 20th century.e century.
If the eradication of smallpox is an indisputable victory, it has two negative consequences: the children who are born after the cessation of the vaccination campaign are not protected against the disease, raising fears of a bio-terrorist attack; a problem quickly solved by the rich countries which stockpiled doses of vaccines in the freezer. The second consequence concerns the African countries where monkeypox is endemic. The smallpox vaccine also protected local populations against this other orthopoxvirus. To respond to fears, the WHO launched monitoring of monkeypox between 1981 and 1986 after which it was concluded that the disease did not represent a major public health problem. People in contact with monkeypox are therefore left with no alternative to protect themselves from the virus.
Monkeypox Explodes With Diminished Smallpox Immunity
A conclusion that resonates strangely with the current situation. In effect, a study published in 2010 and conducted by scientists from the school of Los Angeles School of Public Health concludes that the thirty years following the cessation of smallpox vaccination, theimpact monkeypox has increased by a factor of 20 in the areas monitored in the Democratic Republic of the Congo, the country where the virus is most active. Monitoring data collected between 2005 and 2007 by scientists indicate that the decrease inherd immunity against smallpox, more frequent contact with animal reservoirs of the virus and the increase in human-to-human contamination are the cause of the cases. Most of those infected are young boys under the age of 15, born after the cessation of smallpox vaccination. The scientists note in their paper: Based on our surveillance program, we observed that the risk of contracting monkeypox was inversely associated with smallpox vaccine. Vaccinated people are 5.21 times less likely to get monkeypox compared to unvaccinated people. »
Another more controversial theory states that the disappearance of smallpox would have left an ecological niche free, a concept whose definition is debated according to the disciplines, offering the opportunity for monkeypox to occupy it. This view is supported by University of California scientist James O. Lloyd-Smith, and detailed in a publication published in 2013 that he signs alone. He writes : ” Therefore, eradication may lead to a quantitative increase in the incidence of another infection, but if this leads to theemergence as agent pathogenic endemic depends on additional factors. No scientific data has yet formally validated this theory.
A link to the current situation?
The fact remains that the end of smallpox vaccination and the globalization which increased in the following years allowed the monkeypox virus to prosper and leave the African continent from 2003, via of the dogs of contaminated meadows, and on several occasions in 2018 and 2019 before the situation we know today emerged. Monkeypox is the most common orthopoxvirus in humans. The smallpox vaccines will come out of the freezers to constrain the spread of the monkeypox virus and immunize infected people and their contacts. From now on, 23 countries outside Africa are affected by human-to-human transmission of the monkeypox virus. In the Democratic Republic of Congo, the monkeypox virus is still present and 56 people have died from the disease since the beginning of the year; none in Western countries to date.
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