Study shows previous omicron infection is more protective against BA.2
study in Lancet Infectious Diseases demonstrates that pre-Omicron BA.1 infection was the most protective agent against BA.2 infection (associated with a 72% reduced risk) and conferred greater protection than primary infection with Pre-Omicron SARS-CoV-2 (38%) or three mRNA vaccine doses in People with no previous infection (46%).
The test-negative case-control study involved health care workers in Quebec comparing those who tested positive for SARS-CoV-2 during the Omicron BA.2 dominance period, March 27 to June 4, 2022, with health care workers who tested negative during the same period. Period.
Primary infection of COVID-19 must have occurred at least 30 days before the study period, with pre-Omicron infection occurring between February 20, 2020 and November 27, 2021., 2021, and March 26, 2022. In total, 37,732 putative cases were compared from Omicron BA.2 with 73,507 randomly selected controls.
Of the cases, 1,159 (3.1%) had a primary infection with two doses of the mRNA vaccine, and 1436 (3.8%) had a primary infection with three doses of the vaccine, the authors said. Among the controls, 687 (10.9%) had a primary infection accompanied by two doses of the vaccine, and 821 (13.4%) had a primary infection with three doses of the vaccine.
Hybrid immunity from BA.1 infection plus two or three doses of mRNA vaccine increased efficacy to 96% for >5 months. It is worth noting that a third dose of the vaccine did not give any improvement to that hybrid protection.
“These data provide the immunological context for the importance of hybrid immunity in managing current mutations caused by BA.2.12.1, BA.4 and BA.5 sub variants in populations with high frequencies of vaccination and BA.1 or BA.2 infection,” David wrote. Hui, MD from the Chinese University of Hong Kong, commented on the study. “Another important factor in reducing infection risk is heterogeneous booster vaccination with different platforms to maximize the breadth of vaccine-induced immunity, especially in countries that primarily use an inactivated vaccine.”
September 21 Lancet hits dis study And the Suspension
Agreement paves the way for more global access to Baxolvid
Today, Pfizer announced it has signed an agreement with the Global Fund to provide up to 6 million Paxlovid courses to 132 low- and middle-income countries to help treat COVID-19.
Countries will be able to access the drug through the Global Fund’s existing Epidemic Response Mechanism, which has been used to provide grant support for tests, treatments, personal protective equipment and other items to strengthen health care systems.
Pfizer said in a statement that it expects supply to begin this year, subject to regulatory approval and state request. Countries can purchase supplies through tiered pricing at the nonprofit Pfizer Inc.’s price. Albert Burla, CEO of Pfizer, said contact with the Global Fund promotes equitable access to treatments for high-risk groups in low- and middle-income countries. The company also said the agreement builds on previous efforts to facilitate access.
In US developments, an official from the Food and Drug Administration said this week that the use of updated COVID boosters for children ages 5 to 11 will be allowed in the coming weeks, according to ABC News. Peter Marks, MD, PhD, who directs the Food and Drug Administration’s Center for Biology Evaluation and Research, was speaking at an event with the COVID-19 Vaccine Education and Equity Project. Earlier this month, the new booster was approved for emergency use for people under 12 years old.
September 22, Pfizer Inc. statement
September 21 ABC News a story