Severe obesity may weaken the effectiveness of COVID-19 vaccines in those who have never been infected with the coronavirus, according to a small Turkish study. Additionally, South African researchers have found infection with the Omicron variant of the coronavirus can significantly improve the immune system’s ability to protect against other variants, but only in people who have been vaccinated.

COVID-19 vaccine candidates developed by a Sinopharm subsidiary and Sinovac Biotech to target the Omicron variant were approved for clinical trials in Hong Kong, the companies said on April 16.

Although people who recover from COVID-19 usually gain some immune defenses against reinfection, they get additional protection from vaccines, especially against severe disease, according to two studies published on March 31 in The Lancet Infectious Diseases. Additionally, two gold-standard trials published in The New England Journal of Medicine on March 30 help settle questions about two controversial therapies touted by many early in the pandemic with decidedly mixed results – failure for the antiparasite drug ivermectin and success for antibody-rich blood plasma from COVID-19 survivors.

Comirnaty

The world’s leading COVID-19 vaccine and therapeutic manufacturers continue to develop treatments for the waves of variants as well as life-changing therapies for disease areas outside the world of coronaviruses. The world’s efforts to combat the global pandemic continue to evolve, as does Coronavirus Disease 2019 as variants and subvariants constantly toss volleys of grenades at the battlefront lines.

Two cases of a subvariant of the Omicron variant were identified in Washington state. Two cases were also identified in Houston.

A third booster dose of a COVID-19 vaccine made by AstraZeneca, Pfizer-BioNTech or Johnson & Johnson increases antibody levels significantly in those who have previously received two doses of Sinovac’s CoronaVac shot, a study has found.

Antibodies triggered by Sinovac Biotech’s Covid-19 vaccine decline below a key threshold from around six months after a second dose for most recipients, although a third shot could have a strong boosting effect, according to a lab study.

While several countries are relying on Sinovac Biotech’s coronavirus disease 2019 vaccine to end the pandemic, concerns regarding the shot’s efficacy continue to shroud CoronaVac, which is the second most used Covid-19 vaccine product across the globe.