Rapid vaccine rollout in Israel leads to sharp decline in severe COVID-19
A rapid vaccine rollout in Israel that prioritized older adults led to 67% decline in the ratio of COVID-19 patients aged 70 years or older who required mechanical ventilation compared with patients younger than 50 years, a study showed.
According to the study, which was published in MMWR, approximately 84% of people aged 70 years or older and 10% of people aged 50 years or younger had received two doses of the Pfizer-BioNTech vaccine as of this month.
Yair E. Lewis, MD, PhD, of Maccabi Healthcare Services in Tel-Aviv, and colleagues said the findings of their study reinforced that COVID-19 vaccines can “help limit spread of disease and potentially reduce the occurrence of severe disease.”
“Many countries are currently conducting national COVID-19 vaccine campaigns,” they wrote. “The findings from this study provide preliminary but important evidence of the effectiveness of vaccines in preventing severe cases of COVID-19 at the national level in Israel.”
In December, Israel instituted a national vaccination campaign using the Pfizer-BioNTech vaccine. It prioritized individuals aged 60 years or older, health care workers and individuals with underlying conditions for vaccination.
Rinott and colleagues conducted an ecological study to assess the effect of vaccination on severe COVID-19, which they defined as COVID-19 requiring mechanical ventilation. They used the Israel Ministry of Health database to obtain vaccination and case information.
As of Feb. 9, a total of 2.2 million of 3.6 million vaccinated adults in Israel had been given their second dose. The percentage of people receiving both doses aged 70 years and older, 60 to 69 years, 50 to 59 years and younger than 50 years was 84.3%, 69%, 50.2% and 9.9%, respectively.
Since the implementation of the country’s vaccination program, the ratio of mechanical ventilation in adults aged 70 years and older compared with adults younger than age 50 years dropped from 5.8 to 1 to 1.9 to 1. — a decline of 67%.
The decline “began around the time of commencement of administration of the second vaccine dose. This might reflect the effects of the first dose, an observation that is consistent with the Pfizer-BioNTech vaccine phase 3 results, which demonstrated partial efficacy after the first dose,” the authors wrote.
They noted that the study’s limitations included a reliance on preliminary and aggregated data, a limited ability to account for concomitant effects and possible differences in adherence to mitigation measures between the age groups examined.