Researchers at the University of California, Los Angeles (UCLA), have confirmed that genes from bird flu and human flu combined together can create dangerous new flu strains, mainly in the bird flu prevalent countries including Bangladesh.
The flu season this year is expected to be lengthier and the disease could be pandemic if bird flu becomes highly contagious among humans, researchers predicted in a study, published on Friday.
In Bangladesh, so far eight people had died of bird flue until 2010. However, some 800 people were infected and later cured until 2012, according to the Ministry of Health.
The respiratory virus, which infects pigs and humans only sporadically, spreads mainly through coughs and sneezes.
Flu season occurs during the end of winter and rages for several months among birds, humans and animals. Often the viruses become deadly.
In 2009, H1N1 swine flu outbreak killed 280,000 people worldwide when viruses from humans and animals exchanged genes to create a new virus in a process called ‘reassortment’, the study revealed.
Earlier, the flu killed more than a million people each time when it broke out in 1957 and 1968, the study said.
The researchers have advised the relevant authorities in the bird flue prevalent countries to vaccinate people, poultry and livestock and monitor animals for evolution of new viruses, which could help predict and prevent a probable pandemic disease.
According to the World Health organisation (WHO), China, Egypt, India, Vietnam, Indonesia and Bangladesh have been the hosts to ongoing, widespread of bird flu infections in poultry since 2011.
A research study of the UCLA revealed that the researchers had to work with limited data as they had lacked adequate data for bird and human flu outbreaks in all these six bird flu host countries.
The research study was published by Texas-based Red Orbit Science, Space, Technology, Health News and Information on Friday.
The study said the scientists had to identify indicators of flu outbreaks, such as dense poultry populations, or rain and temperatures that encourage flu transmission.
“For each type of flu, we identified variables that were predictive of the various virus strains,” the study report quoted UCLA postdoctoral research fellow Trevon Fuller as saying.
“We wanted a map of predictions continuously across the whole country, including locations where we didn’t have data on flu outbreaks,” Fuller said.
Using surveillance of influenza cases in humans and birds, the researchers have come up with a technique to predict sites where these viruses could mix and generate a future pandemic, the study said.
The researchers’ models revealed that coastal and central China and Egypt’s Nile Delta are danger zones where bird flu could combine with human flu to create a virulent kind of ‘super-flu’.
Governments can prioritise these zones – and use the researchers’ models to identify other hotspots – for increased monitoring of flu in humans, livestock, poultry and wild birds.
“That could help detect a novel flu virus before it spreads worldwide,” the study said.
Researchers using mice confirms that genes from bird flu and human flu can combine to create dangerous new flu strains.
Swine, which is susceptible to both bird and human flu, could serve as a mixing vessel for ‘reassortment’ between the two viruses.
“The mixing of genetic material between the seasonal human flu virus and bird flu can create novel virus strains that are more lethal than either of the original viruses,” the study quoted another UCLA researcher Thomas Smith.
The research focused on two flu strains that, as studies in mice have shown, can combine with lethal results, that is the seasonal H3N2 human flu, and the H5N1 strain of bird flu that has occasionally crossed over into humans.
Currently, H5N1 has a 60 per cent mortality rate in humans but is not known to spread between humans frequently.
Bird flu has taken a big toll in Bangladesh since its fresh outbreak in 2007. The number of farms has come down to 70,000 from 150,000 over the last five years, according to the Bangladesh Poultry Industries’ Association.