Use of Pfizer Inc.’s COVID-19 oral antiviral treatment Paxlovid jumped 315 percent over the past four weeks, the U.S. Department of Health and Human Services said on May 17, as health officials try to address unexpectedly light demand.

Half of the COVID-19 patients discharged from a Chinese hospital in early 2020 still have at least one symptom two years later, a new study shows. Additionally, new findings suggest patterns of inflammatory proteins in the blood of people with long COVID may someday help guide individualized treatment.

Moderna Inc. on May 4 forecast higher vaccine sales for the second half of 2022 than in the first six months of the year, as the company expects the virus that causes COVID-19 to follow a more seasonal pattern requiring booster shots in the fall.

Moderna Inc. asked U.S. regulators to authorize the company’s COVID-19 vaccine for children under the age of 6, which would make it the first shot against the coronavirus available for those under 5-years-old.

Following the record surge in COVID-19 cases during the Omicron-driven wave, some 58 percent of the U.S. population overall and more than 75 percent of younger children have been infected with the coronavirus since the start of the pandemic, according to a U.S. nationwide blood survey released on April 26.

Pfizer Inc. and the company’s partner BioNTech SE said on April 26 that they had submitted an application to the U.S. health regulator for the authorization of a booster dose of their COVID-19 vaccine for children aged 5 to 11 years.

CureVac and GSK’s second-generation vaccine candidate targeting two recent COVID-19 variants has been shown to be highly effective in preclinical studies on mice, CureVac said, as the biotech firm seeks to catch up with rivals’ development work.

COVID-19 cases and deaths are declining in the Americas, the Pan American Health Organization (PAHO) said on April 20, with infections last week having dropped 2.3 percent and deaths falling 15.2 percent from the prior week. The broad trend comes even as cases have scaled up in North America with an 11.2 percent increase last week, the organization said.

The BA.2 sub-variant of Omicron and its sublineage BA.2.12.1 is estimated to make up more than 90 percent of the coronavirus variants in the United States as of April 16, the U.S. Centers for Disease Control and Prevention (CDC) said on April 19.

Moderna Inc. on April 19 said a COVID-19 booster designed to target the Beta variant as well as the original coronavirus generated a better immune response against a number of virus variants including Omicron.