Two studies published in the New England Journal of Medicine show that the immune protection from Pfizer’s COVID-19 vaccine begins to wane after two months. The first study from Israel found that antibody levels decreased, “especially among men, among persons 65 years of age or older, and among persons with immunosuppression”. “BNT162b2-induced protection against infection builds rapidly after the first dose, peaks in the first month after the second dose, and then gradually wanes in subsequent months,” Laith Abu-Raddad of Weill Cornell Medicine-Qatar and colleagues wrote. “The waning appears to accelerate after the fourth month, to reach a low level of approximately 20% in subsequent months,” they added. A second study from Qatar found that antibody levels rise rapidly after the first dose and then peak one month after the second dose is administered. Despite the waning antibody levels, Pfizer’s vaccine continues to provide strong protection against severe cases of COVID, hospitalizations, and death. The vaccine is still 90% effective and protects against all coronavirus variants of concern, including the delta variant.