MW CDC upgrades its advisory on bird flu. Will Moderna's stock get a boost?

By Ciara Linnane

Agency is now calling for all patients hospitalized with flu to be tested for H5 avian flu

Patients hospitalized with flu should be tested for H5N1 bird flu within 24 hours, the Centers for Disease Control and Prevention said Thursday, upgrading its recent recommendation.

Before now, the agency was advising that patients hospitalized with flu who had been in contact with animals should be tested - but it's now extending that advice to all flu patients.

The latest advisory comes a week after the first human bird-flu death was announced - an individual in Louisiana who had been hospitalized with a severe infection.

"While tragic, a death from H5N1 bird flu in the United States is not unexpected because of the known potential for infection with these viruses to cause severe illness and death," the CDC said at the time.

As of Jan. 6, there were 66 confirmed human cases of bird flu, which has been spreading across the U.S. since early 2022, infecting birds and cattle and leading poultry farms to cull flocks. That in turn has led to a sharp spike in the price of eggs.

For more, see: Why eggs are nearly $9 a dozen in California-and when prices could drop

Highly pathogenic avian influenza A (H5) viruses were detected in U.S. wild aquatic birds, commercial poultry and backyard or hobbyist flocks beginning in January 2022, according to a Jan. 7 report from the U.S. Centers for Disease Control and Prevention. Those marked the first detections in the U.S. since 2016. In total, 130.7 million birds have been affected in all 50 states.

CDC officials said they opted to upgrade the advisory after seeing more patients whose illness cannot be traced back to an infected animal or bird.

"That's a newer finding in the history of H5 - not something that we've seen," Dr. Nirav Shah told reporters on a news call, according to media reports.

Shah said the CDC was not becoming more concerned about the current bird flu outbreak, which it still believes is a low risk for the general public. But he said the system should be able to diagnose cases more quickly to help shape the public-policy response.

Meanwhile, there is no approved vaccine for bird flu in humans, although the national stockpile includes certain shots developed in the past and tested on volunteers. That's because there haven't been enough cases in the U.S. for a full clinical trial.

"Fortunately, current vaccine candidates neutralize the circulating strains in vitro, and these strains so far are susceptible to antiviral agents," said a December editorial in the New England Journal of Medicine.

A number of drug companies are working to develop a vaccine, led by Moderna Inc., which won a $176 million award from the Biomedical Advanced Research and Development Authority to develop its mRNA-based H5N1 vaccine last July.

The award "will support late-stage development for an mRNA-based vaccine to enable the licensure of a pre-pandemic vaccine against H5 influenza virus," the company said at the time.

Moderna's stock $(MRNA)$ was down 2.7% Thursday and has fallen 67% in the last 12 months, while the SPDR S&P Biotech exchange-traded fund XBI has fallen 1.1% and the S&P 500 SPX has gained 25%.

-Ciara Linnane

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January 16, 2025 14:45 ET (19:45 GMT)

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