(Reuters) – The following is a roundup of some of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the illness caused by the virus.
Pollen levels linked to COVID-19 rates
Higher pollen concentrations in the air have coincided with increases in COVID-19 infection rates, a large study shows, suggesting a possible link. Using data from 130 sites in 31 countries, researchers found that airborne pollen levels, sometimes in combination with humidity and temperature, accounted for up to 44% of the variability of COVID-19 infection rates during the spring of 2020. The effect was not connected with pollen allergies, the researchers said. In a report published on Monday in the Proceedings of the National Academy of Sciences of the USA, they explained that in everyone, exposure to pollen reduces the ability of the respiratory tract lining to defend itself against viruses by diminishing the release of the antiviral protein interferon. The study also reports that under similar pollen concentrations, infection rates were halved when lockdown measures were in place, because the lockdowns limited exposure to both the virus and the pollen that diminishes the immune response. “As we cannot completely avoid pollen exposure, we … encourage high-risk individuals to wear particle filter masks during high pollen concentrations,” said coauthor Athanasios Damialis of Technical University of Munich, in Augsburg, Germany. (https://bit.ly/3byfNCc)
Robust vaccine responses seen during pregnancy and lactation
Pregnant and lactating women who received the mRNA vaccines from Pfizer/BioNTech or Moderna had immune responses similar to those seen in non-pregnant, non-lactating women, a new study found. In all cases, the COVID-19 antibodies induced by the vaccines were transferred to the babies via the placenta or breast milk, according to a report published on Monday on medRxiv ahead of peer review. The researchers studied 84 pregnant women, 31 breastfeeding women, and 16 non-pregnant women who received the vaccines. Immune responses were equivalent in all three groups, and all three groups had higher antibody levels than another group of 37 women who were infected with the coronavirus while pregnant. “Dampened response to vaccination has been noted in the past for other vaccines in pregnancy,” said coauthor Galit Alter of the Massachusetts General Hospital in Boston. She added that the study addressed an important question as COVID-19 vaccines are rolled out, given that there is currently “limited to no data on how they work in this population.” Pregnant and lactating women were not included in initial COVID-19 vaccine trials. A study testing the Pfizer/BioNTech vaccine in pregnant women got underway last month. (https://bit.ly/3l1BNZr)
Rapid test can screen for variants of concern
A new test can rapidly screen thousands of nasopharyngeal swab samples for the concerning, more contagious new virus variants first identified in the UK, South Africa and Brazil, researchers said. The test uses probes that change color at different temperatures depending on whether it detects a specific mutation, called N501Y, that is present in all three variants. The test, for now, is not capable of differentiating between them, so positive samples would need further testing to identify the particular variant, said David Alland of Rutgers University in New Jersey, coauthor of a report posted on Monday on medRxiv ahead of peer review. “Our next job, already mostly completed, will be to add to the test so that a second mutation … called E484K, can also be detected,” he said. “This will distinguish variants … from the UK from those of South African or Brazilian origin.” The test should continue to detect these variants of concern even if the virus continues to mutate, he said. In those cases, the temperature at which the probes change color will be altered, and any unforeseen color change will flag a sample as likely containing a new mutant, Alland said. The assay is open-source, so it can be updated by the Rutgers researchers or other teams. (https://bit.ly/30uVj6X)
Antibody combo treatment protects against severe COVID-19
A combination of two monoclonal antibody drugs – bamlanivimab and etesevimab – from Eli Lilly and Co reduced the risk of hospitalization and death by 87% in a U.S. study of 769 non-hospitalized COVID-19 patients with risk factors for developing severe illness, according to trial data released by the company on Wednesday. This is the second late-stage, randomized trial to show that the antibody cocktail is effective at treating mild-to-moderate COVID-19. The previous study, published in January, used a higher dose of the drugs and reduced the risk of hospitalization by 70%. U.S. regulators authorized the combination therapy in February for use in COVID-19 patients age 12 and over who are not yet hospitalized but are at high risk for developing serious complications. European regulators authorized its use in March. “We have few other diseases where we have drugs that can offer this magnitude of benefit,” said Daniel Skovronsky, chief scientific officer at Eli Lilly. (https://reut.rs/3l3Ce5i)
Open https://tmsnrt.rs/3c7R3Bl in an external browser for a Reuters graphic on vaccines in development.
(Reporting by Nancy Lapid; Additional reporting by Michael Erman and Carl O’Donnell; Editing by Bill Berkrot)