Scientists say border workers need to keep being frequently tested even after receiving their vaccinations, to counter risks of them silently spreading Covid-19. One scenario the Te Punaha Matatini researchers modelled, in which a vaccine slashed transmission by just half, vaccinating border workers could actually boost the risk of a significant community outbreak. Their simulation, beginning with a single infected border worker, measured the number of people infected before the first case was detected by testing. "In the short term, there is a potential risk that a border worker may contract Covid-19 and have minimal symptoms," they said. Until more is known about the effect of the vaccine on transmission, we continue to recommend the routine testing of vaccinated border workers to identify infection."

Source: New Zealand Herald March 24, 2021 02:00 UTC