Protection against bird flu is found in our bodies

A key defense that blocks almost every bird flu when it tries to invade our bodies has been discovered by scientists.

Bird flu has been involved in four pandemics since 1918 – killing millions of people.

The research, led by the University of Glasgow, showed that these pandemics and normal winter flus have developed ways to overcome this “powerful barrier”.

The team believes that we will soon be able to predict which of the bird flus currently poses the greatest risk.

Scientists studied secondary events. These are the moments when a person becomes infected from an animal. This jump between species is a critical step in the initiation of a new pandemic.

In laboratory experiments, researchers have discovered a part of our genetic code—our DNA—that is activated in response to infection. It’s called BTN3A3 (although even the researchers admit we’re “stuck” with a clunky name).

Researcher Dr. Rutte Maria Pinto said that “almost all” bird flus are unable to bypass this defense, so “they usually get blocked by it so they don’t jump.”

She added: “The majority of human viruses and indeed all pandemic viruses so far have (resistance to BTN3A3), so they overcome this block and therefore infect.”

There is a constant possibility that bird flu will pass to humans. There are different influenza viruses in wild birds, and poultry pose a high risk due to the large number of farmed animals and their proximity to humans.

The influenza pandemic of 1918 is believed to have started in birds, and it is believed that killed 50 million people. The researchers showed that a form of bird flu called H7N9 developed higher levels of resistance to BTN3A3 in 2011 and 2012 before the first human cases appeared in 2013.

Evolving ways to circumvent BTN3A3 is one of the steps bird flu can take to successfully infect us.

The researchers’ vision is to routinely analyze – or sequence – the genetic code of flus currently circulating in birds, identify the dangerous ones and deal with them.

Prof Massimo Palmarini, director of the Glasgow Center for Virus Research, told me: “In the not too distant future we will be able to put all the pieces of the puzzle together.

“From sequencing a virus, we’ll be able to say there’s a 90% chance of it moving to humans, this virus only has a 10% chance.”

Targeted measures can then be put in place to help control viruses that do have a high surge risk.

The world’s bird populations were hit by the largest avian or bird flu outbreak ever recorded.

The virus – H5N1 – is occasionally passed to people coming into close contact with infected animals, but it is not spread from person to person.

Professor Palmarini said “just over 50%” of virus samples from birds and “all seven” cases found in humans this year had resistance to BTN3A3.

“That’s one level of concern, the other is that the virus has spread like never before,” he told me.

However, the ability to bypass BTN3A3 is only one aspect of the virus’ threat to human health.

Dr Stephen Oakeshott, Head of Infection and Immunity at the Medical Research Council, said: “This interesting study illustrates an important piece of the very complex puzzle that underlies the transmission of viruses between species.

“This type of mechanistic scientific insight, combined with genetic monitoring, can offer a window into future disease risks to inform public health planning.”