Thread by @OhCasavant

🧵 Is there hybrid immunity for measles like for COVID? If so, should that be a public health goal?

Answer from Dr Mansour Haeryfur, President, Canadian Society for Immunology

*Replying in a personal capacity, not on behalf of CSI or UWO

b. Measles & COVID hybrid immunity

"The goal for measles should be herd (population) immunity through vaccination, not breakthrough infections for several reasons:"

c. Measles & COVID hybrid immunity

"With COVID19, we had no tangible choice but to rely on hybrid immunity..." 🧐😳

"...because mRNA vaccines have not been super-effective in “preventing infections". They were great at preventing/minimizing severe illness ..."

d. Measles & COVID hybrid immunity

"When Omicron came along, we lucked out [😲] because this was a highly transmissible version of SARS-CoV-2, similar to measles virus, while primarily affecting the upper respiratory tract without causing severe illness in most cases."

e. Measles & COVID hybrid immunity

"So, this [Omicron] was a blessing in disguise (in my opinion) and helped with hybrid immunity and in reducing the impact of the pandemic."

President of 🇨🇦 Society for Immunology, speaking in personal capacity via personal comm. Mar 2024

f. Measles & COVID hybrid immunity

SARS-CoV-2 is similar to flu in terms of accumulating mutations. Measles virus is much more stable. And we have a choice – that is to use the vaccine and the booster to increase our immunity at individual and population levels..."

g. Measles & COVID hybrid immunity

"One vaccine against measles virus is very effective, & 2nd dose is even more effective...Breakthrough infection-elicited immunity should never be a goal vis-à-vis measles, in my opinion."

h. Measles & COVID hybrid immunity

"This is because if a previously unvaccinated (or not optimally vaccinated) individual contracts measles, the wildtype strain of the virus can cause rare but very serious complications."

cont'd below

i Measles & COVID hybrid immunity

"In addition, the wildtype virus can bind CD150, a cell surface molecule expressed by memory T and B cells (and innate-like T lymphocytes as we reported), thus causing "immune amnesia". "

j. Measles & COVID hybrid immunity

"This means, memory and memory-like immune cells that have accumulated in the body due to previous vaccinations or infections (for/with any pathogens) can be killed by measles virus."

k. Measles & COVID hybrid immunity

"...one could become prone to many unrelated infections simply because she/he has no recollection of previous encounters with microbes of vaccines. This is consistent with measles-induced
immunosuppression, which has been known for decades..."

l. Measles & COVID hybrid immunity

"If we do not optimally vaccinate ...against measles, the so-called herd immunity is not reached, thus potentially compromising other vulnerable members of our communities..."

m. Measles & COVID hybrid immunity

mRNA COVID vax only targeted Spike protein not the actual virions

vs

Measles vax is live attenuated whole virus

n. Measles & COVID hybrid immunity

Not enough vaccinated [but not because of hybrid immunity sales pitch 🤔]. We need respectful vaccine education.

Not for COVID, though, is how I read this. 🤔

o. Measles & COVID hybrid immunity

"Measles induced immunosuppression & heightened susceptibility infections...are well- established but ""immune amnesia" is a subject of intense investigations. ...Regardless...it can be easily avoided by the vaccines that are widely available."

p. Measles & COVID hybrid immunity

For more information, refer to the following papers and interviews:

(Links in Alt text in image)

q. Measles & COVID hybrid immunity

End of email from Dr Mansour Haeryfar, President of Canadian Society for Immunology