Two doses of Pfizer’s COVID-19 vaccine can provide more than 95% protection against infection, severe illness, and death, according to the first nationwide data from Israel.
A single dose of the jab, meanwhile, is associated with 58% protection against infection, 76% against hospital admission, and 77% against death, research published in The Lancet suggests.
The study uses Israeli ministry of health data from between 24 January and 3 April this year, a time when the UK variant was responsible for most of the country’s infections.
By the end of that time period, 72% of people over 16 years and 90% of those over 65 years had received two doses of the Pfizer-BioNTech jab.
For those over 16 years, the vaccine provided 96.5% protection against infection, 98% protection against hospital admissions and 98.1% protection against death, from 14 days after the second dose.
Protection for the elderly was almost as strong, with those over 85 getting 94.1% protection against infection, 96.9% against hospital admission, and 97% against death, a week after receiving their second dose.
Israel’s vaccination programme has been one of the fastest in the world, and the country went from more than 10,000 new virus cases a day in January to just a few hundred in March.
The economy has almost fully reopened and people are going to sporting and cultural events outdoors.
Lead author Dr Sharon Alroy-Preis, of the Israeli ministry of health, said: “As the country with the highest proportion of its population vaccinated against COVID-19, Israel provides a unique real-world opportunity to determine the effectiveness of the vaccine and to observe wider effects of the vaccination programme on public health.
“Until this point, no country in the world had described the national public health impact of a nationwide COVID-19 vaccination campaign.
“These insights are hugely important because, while there are still some considerable challenges to overcome, they offer real hope that COVID-19 vaccination will eventually enable us to control the pandemic.”
Jonathan Ball, professor of molecular virology at the University of Nottingham, said: “Importantly, the study shows that two doses of the vaccine significantly increase levels of immunity and protection.
“This is why it is important that people get both doses, and if UK vaccine policy changes, to get a third dose if offered in the autumn.”
Prof Ball said that as new coronavirus variants emerge, “topping up your immunity with the vaccine boost will be even more important” as the virus acquires genetic changes that may make it more resistant.
He added: “Therefore, it will be important to continue to monitor the potential impact of virus change and vaccine effectiveness.”
Dr Luis Jodar, Pfizer’s senior vice president and chief medical officer of vaccines, said more data is needed urgently about the effectiveness of the vaccine against severe disease and death, and the levels of protection it provides to elderly people.
“Research examining long-term vaccine effectiveness will ultimately play a vital role in tackling the pandemic.”