A recent laboratory study suggests that a single gene mutation could enable H5N1 bird flu to spread between people. The researchers found that a specific mutation, called Gln226Leu substitution, can “completely switch” the virus’s preference from birds to humans. This change would allow the virus to infect human cells more easily and increase its potential for sparking a pandemic.
The study, published in the journal Science, explored what it would take for the H5N1 bird flu virus to switch its preference from birds to people. The researchers looked at the genetic code of the virus that infected the first person ever known to catch bird flu from a cow and found that a single mutation was sufficient to make the virus a better match for human cells.
Currently, the circulating bird flu virus is a much better match for bird receptors, but the new study suggests that with enough mutations, it could become a more efficient infectant for humans. The researchers warn that if the strain of H5N1 currently circulating in the US were to evolve and acquire this mutation, it could potentially lead to deadlier or more transmissible cases.
As of December 4, the Centers for Disease Control and Prevention has confirmed 58 H5N1 infections among people in the US, with most linked to exposure to infected cattle. However, the two remaining infections have no known source and are suspected to have originated in animals. So far, human cases have been mild, but a teen infected in Canada had more severe symptoms.
The study’s findings have significant implications for pandemic preparedness and highlight the need for continued monitoring of the H5N1 virus. With the Northern Hemisphere’s flu season ramping up, there is a possibility that H5N1 could infect a person who is already infected with seasonal flu, potentially leading to gene swapping between the two viruses.
Source: https://www.livescience.com/health/flu/a-single-gene-mutation-could-enable-h5n1-to-spread-between-people-study-finds