The ECD notes 'considerable uncertainty related to transmissibility, vaccine effectiveness, risk for reinfections and other properties'

Experts warn that immunization campaigns are in a race against time to contain the new strain of the pandemic that is taking over the world

Albert Bourla believes COVID-19 inoculations will become an annual affair; says bringing down pool of people susceptible to virus crucial to halting pandemic

Largest study in world followed about a fifth of COVID-positive Israelis after recovery, and found 154 got reinfected, indicating immunity is high but far from absolute

Research by UN and Switzerland shows that even though the level of antibodies fade, body maintains sufficient memory B cells, and they manage to stave off reinfection

One paper shows body retains high level of memory B cells for lengthy period; two others examining statistics indicate reinfection chances very low for at least half a year

Probe as to why patient, 74, who had been clear of infection, became fatally ill finds that second illness was caused by a mutated coronavirus variant

Oxford University report finds 'good news,' says examples of reinfection relatively rare and few cases found did not exhibit symptoms

Experts say disappearing antibodies don't spell the end of immunity, following seemingly alarming British study

Admission comes as first confirmed Israeli and American reinfections documented in journals; Expert: Don’t worry, these are exceptions that prove rule of immunity