Pakistan to get 2.8 million AstraZeneca vaccine doses from COVAX

Henrietta Strickland
February 22, 2021

Pollard believes policies of initially vaccinating more people with a single dose may provide greater immediate population protection than immunising half the number of people with two doses, especially in places where the Oxford vaccine is in limited supply. The researchers further added that the governments should definitely vaccinate the people twice after the interval of three months has passed as in the long term the second dose would give long-lived immunity against the virus.

As part of the study, the scientists collated the randomised controlled trials data from South Africa, Brazil, and the United Kingdom.

Canada has not yet approved the AstraZeneca-Oxford shot, but is set to receive millions of doses if it is authorized by Health Canada.

"The big problem that is coming up is the mRNA is able to retain a lot of their effectiveness with the variants, AstraZenecas' vaccine may not perform as well with variants and that seems to be the thing that is really holding things up".

Meanwhile, another 1,245 new COVID-19 cases were reported in the country on Friday, bringing the country's total infection count to 568,506.

France, Belgium and Germany are among European Union countries to recommend that Oxford's vaccine be given only to under 65s. To establish the efficacy of a single dose, the authors analysed participants who had had their first standard dose and had tested positive for Covid-19 more than 21 days afterwards.

The efficacy of the vaccine was found to be 81.3% with a longer interval of 12 weeks between the first and second dose, compared to 55.1% efficacy in case of a six-week gap, according to the Lancet study. Efficacy results were supported by immune response results in 18-55 year olds, which found that binding antibody responses were more than two-fold higher in the group having their two vaccines with a longer delay.

The study also confirmed AstraZeneca's findings from earlier this month that showed that the vaccine had 76% efficacy against symptomatic coronavirus infection for up to three months after the first dose. In addition, antibody levels against the SARS-CoV-2 spike protein remained at similar levels for 3 months.

However, the study authors mentioned that they were not sure if the single dose of the vaccine would extend its protective shield for a period of more than three months as the study was conducted with a time period of up to three months only.

Professor Pollard said: "It is important to understand whether vaccines can reduce Covid-19 transmission".

Other reports by Click Lancashire

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