Possible Virus Hybridization Cause for Concern
The H5N1 avian influenza and human seasonal influenza could potentially combine to create hybrid strains that combine the severity of the bird flu with the pandemic ability of H1N1, according to a study funded by the U.S. National Institutes of Health (NIH), the Japan Society for the Promotion of Science, the Ministry of Education, Culture, Sports, Science and Technology of Japan, and the Japan Science and Technology Agency.
In experiments with mice, a single gene segment from the human seasonal flu virus was able to combine with the avian H5N1 virus in order to form a highly pathogenic form. According to Yoshihiro Kawaoka, a virologist at the University of Wisconsin-Madison and senior author of the study, some of the hybrids were able to spread throughout the mouse population easier than the H5N1 virus.
The H5N1 virus has caused 262 human deaths worldwide, but, as of yet, it cannot spread from person to person, only from bird to person. Experts worry that a hybridized version may be able to transmit among humans.
The researchers advised that surveillance of viral populations is necessary to monitor the potential emergence of highly pathogenic viral variants.
The study was reported in the February 22 early online edition of the Proceedings of the National Academy of Sciences.
SOURCE: University of Wisconsin-Madison