This so-called mutant flu was created from a combination of two strains of influenza, known as H5N1 and H1N1. The research was going on last year, but didn’t get major attention until December 2011, when the scientists tried to make their results public. Suddenly, the news was full of stories about a potentially dangerous form of flu. In the U.S., the National Science Advisory Board for Biosecurity stepped in and told the researchers that they were not allowed to share the details of their experiments. There were a lot of discussions, with health leaders such as the World Health Organization weighing in. In March, the science board decided to let the scientists publish their results. A team of researchers in Wisconsin published its study this week.
But why did these scientists want to make a mutant bird flu in the first place?
H5N1 is a type of influenza that has been very deadly to humans. It was discovered 15 years ago when a boy in Hong Kong died. Scientists found out that this new flu, H5N1, was carried by chickens. This flu is commonly called “avian” influenza in the news.
Although H5N1 is deadly to humans, it has mostly stayed in birds over the last decade and a half. And so far, H5N1 has not been able to spread from person to person. A few hundred people have died from H5N1 flu, but they are mostly people who come into close contact with chickens and other birds in countries like China, Indonesia, Egypt, India and Vietnam.
What scientists are afraid of is that H5N1 could someday mutate into a type of flu that could spread from person to person. Because humans have not been exposed to this kind of flu, we don’t have an immunity to H5N1, and our current flu vaccines wouldn’t protect us. Scientists fear that H5N1 could cause the next great flu pandemic.
So back to the mutant flu research. The scientists took wild H5N1, which can’t be spread person to person, and mixed it with parts of the H1N1 virus, which can spread to humans (and as we learned in 2009 during the global pandemic, it spreads quickly!) The researchers checked millions of viruses for mutations until they found a virus that could spread in mammals, and then they tested it. What they found was a little scary: It only took four small changes in the H5N1 virus to start spreading in the air.
|H5N1 viruses (colored gold) are grown in a lab.|
Image courtesy CDC/Cynthia Goldsmith; Jacqueline Katz; Sherif R. Zaki
Thanks to these new studies, we now know how easily a person-to-person type of H5N1 flu may develop. But instead of being scared, we should be hopeful, because we’re also one step closer to a better flu vaccine and better ways to monitor the flu.
To learn more about H5N1 flu, visit WHO’s website. You can also learn more about the different types of flu through our post, “So, what causes the flu?”