Story at a glance Researchers reviewed the positive COVID-19 test results of 800 people--400 vaccinated and the same number unvaccinated. The South African variant was 8 times more likely to show up in the test of a person who received both doses of the Pfizer vaccine. The findings defied researchers initial expectations, although they concluded that given the relatively small sample size more research is needed. ______________________________________________________________ Israeli researchers found in a study released Saturday that the COVID-19 mutation first discovered in South Africa has a greater likelihood of “breaking through” the Pfizer-BioNTech vaccine than other prominent variants. The study,...