3 ms·
Measles, polio, and smallpox beg to differ. The varicella vaccine is fairly new, but I haven’t heard of a vaccine-resistant strain evolving. Pertussis seems to
by amluto 5y ago
Measles, polio, and smallpox beg to differ. The varicella vaccine is fairly new, but I haven’t heard of a vaccine-resistant strain evolving. Pertussis seems to be an odd duck, and its vaccine is not as effective as people would like.
History is mixed here, but most of the mandatory vaccines seem to be extremely effective and to work well for at least decades.
- manwe150 5y agoThose also have low breakthrough rates (assisted by high vaccination percentages), giving it relatively no opportunity to evolve. They also had millennia to reach (and then work to maintain) peak fitness, while COVID is still encountering beneficial mutations somewhat frequently.
- D_Alex 5y agoPresumably also the human species had time to co-evolve some resistance to these illnesses. I shudder to think at the cost... hundreds of millions of lives for smallpox alone...