Vaccine makers rose in premarket trading on Wednesday as investors reacted to rising flu and COVID-19 cases in the U.S. following the latest respiratory illness data announced by the CDC last week.

Novavax up 9%; Moderna up 7%; Novo Nordisk, CureVac up 2%; BioNTech up 1%.

Their upsurge came after the U.S. CDC said that COVID-19 activity was rising in most areas of the country alongside a concurrent increase in seasonal flu activity, especially among young children. “There is still time to benefit from getting your recommended immunizations to reduce your risk of illness this season, especially severe illness and hospitalization,” the agency added in a statement on Friday.

The CDC also reported a “very high” prevalence of respiratory syncytial virus (RSV) particularly in young children. Pfizer (PFE) and GSK (GSK) offer Abrysvo and Arexvy vaccines for RSV, respectively, Moderna (NASDAQ:MRNA) recently joined the market with its mRESVIA vaccine.

Meanwhile, public concerns over H5N1 bird flu spread after state health officials in Louisiana reported the first death linked to that respiratory virus in the U.S. However, despite the fatality, the WHO said that the risk to the general population from bird flu remained low.

The infected individual, who was older than 65, had underlying medical problems, and it was the only bird flu case in the state, the Louisiana Department of Health said, adding that there was no evidence of human-to-human transmission.