Is there a vaccine for H5N1? What we know as first person with severe case of bird flu died in United States

The H5N1 bird flu has been reported to have caused the death of a patient in Louisiana. Such a case poses a significant threat to public health and can be considered an important stage in combating avian flu. It is the first case of death due to H5N1 being reported in this country since 2022.

The number of human H5N1 cases as of January 6, 2025, stood at 66, confirmed since 2024, and accumulative cases from 2022 amounted to 67.

Several H5N1 vaccines are already available and stockpiled in national supplies. These vaccines were made on the basis of previous circulating strains of the virus, but it is hoped that they will still provide some cross-protection against serious illness caused by current strains.

The initial studies reported so far reveal that the already established vaccine candidates were in a position to neutralize circulating H5N1 strains within the lab environment. Yet, extensive clinical trials cannot be executed as, to date, not enough human infections exist for a comparison study to occur.

Much of the emphasis has been on mRNA vaccines, particularly after successful application in the COVID-19 vaccines. The Biomedical Advanced Research and Development Authority (BARDA), funded under the U.S. government, has awarded Moderna $176 million to work on an improved mRNA H5N1 vaccine that is being advanced to early-stage testing safety and efficacy.

Other companies, such as Pfizer and GlaxoSmithKline, are also developing mRNA-based approaches.

Promising results were obtained in animal studies recently, such as in the case of mRNA vaccines. For example, research led by the Centers for Disease Control and Prevention (CDC) showed that an mRNA-based H5N1 vaccine induced strong antibody responses in ferrets, which could survive lethal doses of the virus.

According to Time magazine's report, experts, such as Dr. Drew Weissman, consider it an advantage of mRNA technology that with this product, updates can easily be done within a short period of time in the vaccine adapting to emerging strains.

Although the mRNA vaccines can be accelerated, the clinical trials will take more time to ensure safety and efficacy.

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H5N1 bird flu death details

On December 18, 2024, the CDC first confirmed a severe case of H5N1 bird flu in the United States.

The patient was admitted to the hospital due to direct contact with sick or dead birds in their backyard flock. This could, therefore, be indicative of an importation of avian disease to humans.

Louisiana's health department said in a public statement:

"The patient was over the age of 65 and was reported to have underlying medical conditions."

Although this raises the neck hairs, the public health authorities allayed fears that the general population is still a low risk as no evidence exists at all for person-to-person transmission.

This case is alarming because it is a departure from previous cases, which were primarily linked to poultry farms or wild birds.

The Louisiana Department of Health is actively tracing contacts and administering necessary antiviral treatment to the exposed individuals.

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Global context and preparedness

More than 950 cases have been reported to the World Health Organization (WHO) over the globe, of whom half have died due to the H5N1.

Some countries, like the UK, have already started stocking vaccines. They recently ordered five million doses of an H5 influenza vaccine to be prepared for the future.

Experts caution that H5N1 currently does not spread easily between humans, but mutations could alter that, posing a potential pandemic threat.

Therefore, both vaccine development and viral mutation research and surveillance need to be constantly done as a public health strategy going forward.