CEID youth ambassadors discuss raising concerns with H5N1
Youth ambassadors to Wayne State University's Center for Emerging and Infectious Diseases, Shams Hasan and Simran Adnani, recently prepared a paper regarding raising concerns about H5N1.
H5N1 leading to raising concerns
Shams Hasan, Simran Adnani
Center for Emerging and Infectious Diseases, Youth Ambassadors
At what point does a non-concerning virus become a pandemic-level concern? In the case of the H5N1 virus, the answer seems to be when there is evidence of human-to-human transmission.
H5N1 is a subtype of influenza that primarily infects birds, hence its other name, "bird flu" (WHO, 2024). However, it has the potential to infect humans, and when it does, it often leads to severe illness or even death. The virus predominantly affects the respiratory system. There are many variants of the H5N1 virus, and it can easily spread from an infected animal to other animals or humans. Scientists have grown increasingly concerned since a teenager in Canada was hospitalized in critical condition after being infected with the H5N1 avian virus (Nature, 2024).
This particular strain of the virus has been shown to have mutations that make it more capable of infecting the human airway (Nature, 2024). Researchers are still investigating the source of the teenager’s infection, but according to Bonnie Henry, "The adolescent did not work or live on a poultry farm, and researchers have found no signs of H5N1 infection in household pets" (Nature, 2024). The inability to pinpoint the source is particularly concerning because understanding where this mutated form of the virus originated and under what conditions it emerged is critical for controlling its spread. The strain that infected the teenager is closely related to the one typically found in birds. However, what sets this strain apart is that it carries a mutation that enhances its ability to replicate in humans who are not the usual hosts for this virus. Scientists are also considering the possibility that the virus may have adapted further within the teenager's body, making it a more effective human pathogen.
The reassuring news is that, so far, there is no clear evidence that this strain can transmit from one human to another. This means that while the virus has become better at infecting humans, it does not currently pose an imminent threat of human-to-human transmission. More recently the Scripps Research Institute researchers published a report in the journal Science where they described a single mutation which would be needed to make the H5N1 virus adept in attaching to human cells. This is worrisome news given the fact that viruses can mutate very fast.
As if now, scientists are continuing their research to fully understand the virus and its potential risks. It is important to remain aware that if the virus acquired mutations enabling efficient human-to-human transmission, it could lead to another pandemic. This calls for aggressive surveillance and pandemic preparedness.
Citations
“Influenza: A(H5N1).” World Health Organization. Accessed December 3, 2024. https://www.who.int/news-room/questions-and-answers/item/influenza-h5n1.
Ledford, Heidi. “Why a Teenager’s Bird-Flu Infection Is Ringing Alarm Bells for Scientists.” Nature News, November 20, 2024. https://www.nature.com/articles/d41586-024-03805-4.