The most effective way to prevent and control avian influenza in humans is through vaccination, although the effectiveness of the vaccine may vary depending on the strain.
This is the conclusion drawn by the authors of a recent review that examines the current research on vaccines for bird flu in humans.
These findings were published in the peer-reviewed journal Human Vaccines & Immunotherapeutics, and focus on the existing research in this area.
The timing of this news is particularly relevant, given the recent report on Wednesday 22nd May that the bird flu strain H5N1 had once again transmitted from cattle to a human in America. This has raised concerns about the potential for human-to-human transmission, which could have serious consequences.
The avian influenza was first identified in US cattle back in March. Since then, the virus has primarily spread from cow to cow, and researchers have found very high levels of the virus in raw milk (pasteurized milk is safe, as it has shown viral RNA but not infectious virus). So far, only two people have been confirmed to have contracted the bird flu virus.nts — US farmers — only reported eye symptoms and with treatment they made a full recovery.
After testing the first human case, it was discovered that the strain had evolved to better infect mammalian cells. However, if the infected human did not pass it on to another person, the spread likely stopped there. With the second case, the CDC has stated that it has been closely monitoring influenza surveillance systems, especially in affected states. “There has been no indication of unusual influenza activity in people, including in syndromic surveillance,” they state.
The current concern is that if the H5N1 continues to have the opportunity to change in an environment like crowded cattle farms, and if this goes on for long enough, it may develop a form that can easily spread to humans.
A new study by a team at the University of Georgia, USA, suggests that vaccines are still our main defense against potential spread of avian influenzas like the H5N1 and others.
“The H5N1, H7N9, and H9N2 types of avian influenza virus pose a double threat, causing not only significant economic losses to the global poultry industry but also being a potential hazard to human health.”The lead author, Flavio Cargnin Faccin, along with mentor Dr. Daniel Perez from the University of Georgia, USA, analyzed the current research on human vaccines for avian influenza. They found that bird flus are a significant public health concern due to spillover events and human cases. The research shows that vaccination is still the main defense against these viruses. The team studied vaccines tested in mice, ferrets, non-human primates, and human clinical trials of bird flu vaccines to assess their effectiveness.
forms and exciting new avenues.
The analysis conducted indicates that inactivated vaccines are a secure and cost-effective choice that primarily stimulate humoral immunity — the section of our immune system that generates antibodies.
Lively weakened influenza vaccines (LAIVs) are recognized to prompt a more comprehensive immune reaction than inactivated vaccines, triggering not only antibody production but also mucosal and cellular defenses. In this analysis, the writers propose that this broader response may provide greater protection, although they also suggest that further research is necessary to fully comprehend and utilize its potential advantages for both human and agr
The review looked at different vaccination options for bird flu, including traditional egg-based vaccines and newer options like virus-like particle (VLP) vaccines and messenger RNA (mRNA) vaccines. While VLP vaccines have shown promise in studies with mice and ferrets, there is limited data on their effectiveness in humans. Similarly, mRNA vaccines have produced strong immune responses in animal studies, with some promising results from a small human trial. The authors recommend further research and use of these alternative vaccine options for bird flu.A variety of vaccine platforms will be essential for improving readiness for pandemics and reducing the risk of avian influenza viruses.
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