4 July 2022

Vaccine benefit does not change with weight

Communicable Disease COVID-19 Live blog

And the CDC now recommends vaccinating all children over six months.


Your weekly pandemic wrap from Australia and around the world.


4 July


Covid vaccines are as effective in people who are overweight and obese as they are in healthy weight people, research suggests.
A paper using pre-Omicron data published in the Lancet Diabetes & Endocrinology reported the outcomes of a population-based cohort study involving more than 9 million adults in the UK, examining the effectiveness of one, two or three doses of vaccine against hospitalisation or death from covid.
Around one-quarter of the study cohort had had three doses of vaccine, around half had had two doses, 3% had had one dose and the remaining 19% were unvaccinated by November 2021.
The analysis suggested that, compared to the unvaccinated, those who had had two doses and were underweight had half the odds of hospital admission from covid and those who were healthy weight, overweight and obese had one-third the odds. A similar pattern was seen for the risk of death from covid.
After a third dose, the odds of hospitalisation was 95% reduced in those who were underweight or obese, 93% reduced in those of healthy weight and 92% reduced in those who were overweight.

The US Centers for Disease Control has recommended that all children aged 6 months to 5 years get vaccinated against covid, while Australia’s TGA has given the green light to Pfizer to apply for registration of its vaccine in this age group.

The US is pushing for all covid boosters to be bivalent and include Omicron subvariant BA.4/BA.5 spike protein components, according to a statement from the Food and Drug Administration.
While clinical trials are already under way for vaccines modified for Omicron BA.1, the FDA says “manufacturers will also be asked to begin clinical trials with modified vaccines containing an Omicron BA.4/5 component, as these data will be of use as the pandemic further evolves.”

Three doses of covid vaccine are 65% more effective than two doses at preventing hospitalisation or death from Omicron, according to a non-peer reviewed Australian study.
A paper published on the Lancet’s preprint server reported the findings of a cohort study in more than two million infection-naïve Australians aged over 40 years, followed from 1 January 2022. Just over three-quarters had had two doses of vaccine, nearly one-quarter had had two doses, and 1% had had just one dose.
Three doses significantly reduced the risk of hospitalisation and death overall, but among those aged 65 years and older it reduced the risk by 70% and among those with comorbidities it reduced the risk by 60%, compared to 47% effective in those aged 40-64 years.
Researchers estimated that for every 192 people aged 70 or older who received a third dose of vaccine, one hospitalisation or death was avoided.

The global covid rollercoaster rolls on, with an 18% increase in new infections reported in the past week after a long run of decreased case numbers.
The latest WHO figures show 4.1 million new cases were diagnosed in the past week, although the rate of deaths remained similar to the previous week. New infections increased in all regions except Africa and the Western Pacific region.
This week also marked a devastating pandemic milestone for Australia as total covid deaths exceeded 10,000.