There have been many concerns over how much immunity a single dose of Pfizer and BioNtech COVID19 vaccine can provide. However, scientists from Israel have claimed that the efficiency of one dose of the vaccine is much lower than expected. Israel is undergoing its third nationwide lockdown just like the UK. The country has vaccinated more than 75 percent of its older population with one dose of the vaccine. Early reports of vaccine rollout have confirmed that the first dose of the vaccine has resulted in a 33 percent drop in COVID19 cases as compared to the efficiency of 52 percent in clinical trials of the vaccine. A study from the Clalit Research Institute has compared the data of infection of 200000 people in the age range of 60 years and above, who have not been inoculated with the infection data of 200000 people of the same age range who have received one dose of the vaccine. These people have been observed for 11 days after the vaccination. On day 14, there has been a major reduction of 33 percent in the rate of positive tests for COVID19 in people who have been vaccinated. This reduction has been the same between days 15 and 17.
The findings of this report have raised doubts as the clinical trials of the Pfizer vaccine have shown 52.4 percent efficacy after the first dose of the vaccine. The data from Public Health England has shown that the first dose of the vaccine can provide 89 percent immunity from days 15 to 21. The Clalit Research Institute has reported that the findings of its study have included only older people who have been under the age group of 60 years and above whereas the clinical trials of Pfizer and BioNtech vaccine have included younger people as well. The Clalit study has found infected people as per the lab tests of those who have chosen to be tested at the same time whereas Pfizer studies have referred to those with the symptoms of the disease. The UK government has prioritized getting the maximum number of people who are in the high-risk category vaccinated with only one dose of the vaccine. At the same time, health officials from the UK government have ensured people that they will be getting the two doses within the specified time. Experts have revealed that the data shows that chosen 12-week gap between two doses of AstraZeneca and Oxford vaccine is quite effective; however, there are no data available to prove the same for the Pfizer vaccine.
UK chief scientific advisor Patrick Vallance has said that when any drug or vaccine comes into the real world, it is rarely quite as good as it shows in the clinical trials. Nevertheless, health experts need to look into reports coming from Israel. Experts from the London School of Hygiene and Tropical Medicine have said that the UK government will soon have its own data, which will show the efficiency of the first dose of the different vaccines which are currently in use in the country. The government is going to wait for robust data before any policy change.