Having two doses of vaccine does not keep you away from COVID-19, as recent cases show us. This is because Covid’s vaccines are not 100% effective at preventing infection. Additionally, some new strains of Covid have become very common. Other new strains are incompletely tested for how long immunity from Covid lasts following vaccination. Nevertheless, vaccinated people are less likely to succumb to serious complications from the disease, and therefore they might get treated at home and the virus is highly unlikely to lead to death.
Recent data shows why vaccinated people might not be fully protected. For instance, in the case of the Pfizer vaccine, it was discovered that those who were vaccinated in January were just 16% resistant against symptomatic infection, while the efficacy for those vaccinated in April was at 79%. Another study revealed that Pfizer is in fact 88% against the new delta variant.
“There will always be a proportion of individuals who will still remain susceptible to infection and illness. There are also two other factors that impact vaccine effectiveness: (1) waning immunity — we still don’t know how long vaccine-induced protective immunity lasts. This is very likely to be a factor in those elderly and more vulnerable individuals who were vaccinated early in the vaccine rollout program,” explained virologist Lawerence Young.
Moreover, he explained that recent outbreaks affecting vaccinated people can be blamed on the new delta variant that is more infectious.
Because people in some areas have begun contracting a strain of the virus that was previously uncommon, more research into this is needed. “We need to better understand how infectious fully vaccinated people who become infected are, as this will help to better predict the situation in the coming months” noted professor Steven Riley.