PolitiFact | Claim from Giuliani on Covid-19 spread ‘wrong on every level’

…Public health authorities have encouraged people who have had Covid-19 to be vaccinated, because the vaccine provides a more robust immunity than antibodies from the infection…
https://www.politifact.com/factchecks/2021/jun/01/andrew-giuliani/giuliani-claim-about-covid-19-transmission-not-bac/

Covid: chemicals found in everyday products could hinder vaccine

"People with high exposure to PFAS have a non-protective and very low antibody levels after four vaccinations for diphtheria and tetanus," Grandjean said. "So if a vaccine for Covid is similar, the PFAS will likely inhibit the response from a vaccine. But it is an unknown at this stage."

https://www.theguardian.com/world/2020/nov/17/chemicals-found-in-everyday-products-could-hinder-covid-19-vaccine

Covid-19 antibodies: Spanish study has a scary takeaway about coronavirus immunity - Vox

One of the worst coronavirus outbreaks in the world isn’t anything close to a worst-case scenario. https://www.vox.com/2020/5/16/21259492/covid-antibodies-spain-serology-study-coronavirus-immunity

WHO warns that few have developed antibodies to Covid-19

Herd immunity hopes dealt blow by report suggesting only 2%-3% of people have been infected ...
https://www.theguardian.com/society/2020/apr/20/studies-suggest-very-few-have-had-covid-19-without-symptoms

Antibody Study Shows COVID-19 Rate of Infection May Be up to 85 Times Higher Than Reported

A study in a county in California suggests that the prevalence of people infected with the coronavirus is much higher than previously thought, potentially complicating decisions on whether to end widespread lockdowns.
https://www.newsweek.com/covid-19-coronavirus-antibodies-infection-higher-1498740

Having older brothers increases men's likelihood of being gay -- CNN

Science, not statistics, draws a connection between male homosexuality and having older brothers, due to a mother's antibodies fighting a Y-chromosome-related protein.....
http://www.cnn.com/2017/12/11/health/men-older-brothers-gay-study/index.html

And Now the Good News #260: Antibody Attacks 99% of HIV Strains! - YouTube

https://www.youtube.com/watch?v=bytxnh1mmKw&t=190s