A study by Israel's Clalit Research Institute and Harvard University has found that adolescents who have received two doses of the Pfizer-BioNTech COVID-19 vaccine are less likely to contract symptomatic Coronavirus disease. The risk of infection also drops by 90 percent with the Pfizer COVID-19 vaccine.

According to a press release issued in the study, the data provides a "strong argument" in favour of choosing to get vaccinated, particularly in those countries with widespread infection due to the virus.

"These data provide much-needed real-world evidence to help parents make informed decisions about vaccinating their adolescent children," said Ran Balicer, senior author of the study and chief innovation officer at the Clalit health care service.

The study has come at a time when countries across the world are struggling to counter surging cases of COVID-19 among children and adolescents. It has also increased the risks related to safety of students at schools.

The research assessed the effectiveness of the vaccine against the delta variant of COVID-19. About 94,354 vaccinated adolescents aged 12-18 participated in the study as they were matched against a control group of unvaccinated teens with similar personal, clinical and demographic characteristics.

As per the data, the risks of infection dropped significantly for fully vaccinated adolescents at least 7-21 days after they received their second dose of Pfizer vaccine.

Furthermore, Pfizer also performed a smaller trial with the participation of 2,260 teens aged 12 to 15 in the US. The trial found that the COVID-19 vaccine was 100 percent effective against symptomatic disease among the age group.