Ellen Phiddian
Cosmos science journalist
Vaccines are highly effective at preventing death from Delta
A Scottish study of 100,000 Delta-positive people has found that the AstraZeneca and Pfizer vaccines are highly effective at preventing death: 91% and 90%, respectively.
The research, which is published in the New England Journal of Medicine, examined data on vaccination status, COVID testing, and mortality across the Scottish adult population from April to August 2021.
Among the 114,706 adults who tested positive to COVID-19 in the study period (with 99.5% of these infections being the Delta variant), 201 died. Vaccination coverage across the population was heavily skewed, with only 380 out of 8,523 subjects aged over 60 unvaccinated, compared to around half of the 16-39 age population.
Adjusting for age and demographic factors, the researchers found that the AstraZeneca vaccine was 91% effective at preventing death, and slightly more effective in the population aged over 60. The Pfizer vaccine was 90% effective, and peaked in efficacy among those aged 40-59.
No vaccinated subjects between the ages of 16 and 39 died during the study period, compared with 17 who were unvaccinated.
Don’t worry about steroid side-effects for severe COVID-19
The steroid dexamethasone has been gaining interest as a treatment for severe COVID-19, with growing evidence that it can reduce mortality in some patients.
This evidence has been tempered, however, by concerns that it has negative side-effects – particularly at higher doses.
Researchers from the George Institute for Global Health have delivered data in a paper in JAMA showing that a higher (12mg) dose of dexamethasone doesn’t reduce mortality any better than a 6mg dose, but nor does it have worse side-effects.
“Our study found no differences in the adverse event rates between the two doses. While there had been reports of infections with so called ‘black fungus’ in patients with COVID-19 with a weakened immune system, our study found no increase in infection rates with the higher doses of steroids,” says co-author Professor Bala Venkatesh, a researcher at the University of Queensland and the George Institute.
“Whilst the data do not provide unequivocal evidence that dexamethasone 12mg is better than 6mg, we saw a trend towards reduced requirement for life support and mortality at the higher dose without any increase in risk of serious infections,” adds co-author Professor Vivek Jha, from the George Institute India.
“As dexamethasone is cheap, easily available and indicated for the treatment of COVID-19 patients with critically low oxygen levels, even a small difference in death rates or health outcomes could lead to important clinical and health economic benefits at the population level.”
Vaccines don’t cause early pregnancy loss
A study of over 18,000 pregnant people has found no link between COVID-19 vaccines and pregnancy loss.
Published in the New England Journal of Medicine, the research tracked 18,477 Norwegians, all of whom were pregnant or had miscarried, and roughly 5% of whom were vaccinated.
“There is a lot of misinformation regarding possible effects of COVID-19 vaccinations on pregnancy and fertility,” says Dr Alex Polyakov, an obstetrician and senior lecturer at the University of Melbourne, who was not involved in the study.
“Millions of women in these circumstances have been vaccinated up to date, and there is no suggestion that COVID-19 vaccination has any impact on either short or long-term fertility.”
He says that this study adds to the growing body of data on fertility and vaccination.
“This Norwegian study concentrated on the risk of miscarriage and its possible association with COVID-19 vaccinations. The results are reassuring in that it found no increased risk of miscarriage following either one or two doses of COVID-19 vaccination.
“The message is clear: there are very few reasons not to get vaccinated, and trying to conceive or being pregnant are not among them.”
More science, but fewer female scientists, after the pandemic
The COVID-19 pandemic prompted an explosion of scientific publishing, as researchers raced to better understand the virus. But an Italian study has found that the gender gap was exacerbated during the early pandemic, with women submitting fewer manuscripts than men – especially in the medical field.
The researchers, who have published their findings in PLOS One, examined submission data for 2,329 journals – all published by academic giant Elsevier – from February 2018 to May 2020.
While there was a 30% jump in submissions between February and May 2020 (compared to the same months in 2019), men were responsible for many more of these than women.
The researchers conclude that the pandemic, and subsequent work-from-home orders, helped to create an environment that was advantageous for male researchers.
COVID recovery plans don’t take climate into account
The Lancet’s annual report on health and climate change has highlighted the fossil-fuel intensive economic recovery plans of a number of countries, pointing out that they do not take the Paris Agreement into account.
The report highlights the risk to human health of climate change, encompassing food and water insecurity, heatwaves, and a greater risk of infectious disease spread.
“The Lancet Countdown’s report has over 40 indicators and far too many of them are flashing red,” says Professor Anthony Costello, executive director of the Lancet Countdown – the journal’s climate change tracker.
“But the good news is that the huge efforts countries are making to kick-start their economies after the pandemic can be orientated towards responding to climate change and COVID-19 simultaneously.
“We have a choice. The recovery from COVID-19 can be a green recovery that puts us on the path of improving human health and reducing inequities, or it can be a business-as-usual recovery that puts us all at risk.”