CDC

Indigenous Peoples' Higher Risk to Bird Flu Driven by Genetics, Historical Isolation

Terri Hansen
1/13/14

Studies of indigenous populations in Alaska and Australia by researchers at Australia’s University of Melbourne have found that genetic differences is the driver that puts Indigenous Peoples at higher risk of severe complications from the new, severe strain of Avian influenza or bird flu called H7N9, now circulating in China and Taiwan.

The H7N9 virus has not been detected in people or birds in the United States.

RELATED: Avian influenza: Public health readiness and surveillance

The Australian researchers studied 31 populations from different continents, and included Alaska Natives based on 1919 data, study co-author Katherine Kedzierska, associate professor at the University of Melbourne’s department of microbiology and immunology, told ICTMN.

The 1918-1920 Spanish flu decimated Indigenous Peoples worldwide. Historical evidence indicates indigenous populations have been disproportionately affected more by influenza pandemics than other population groups.

“This is a new strain in humans,” Kedzierska said. “We have to protect everybody so that is why we tested preexisting immunity in everyone.”

The researchers tested cellular immunity, or pre-existing immunity, and found the prevalence of T-cell immunity depends on ethnicity and that Indigenous people, owing to their historical isolation lacked a key protein necessary to fight the virus. The researchers found that just 16 percent of the Indigenous populations in Alaska and Australia had a robust T-cell response, compared to 57 percent of non-Native populations.

“Genetics played a key role in new emerging influenza strains,” said Kedzierska. “Indigenous people are vulnerable to positive pneumonia and respiratory stress syndrome, and high mortality rates. We think it is caused by centuries of isolated populations. We know that Europeans have had influenza outbreaks for centuries so have more protective mechanisms, but if it’s a novel strain, Indigenous populations are more sensitive.”

Kedzierska said this would be true for any influenza virus, or new virus to which we don’t have antibodies.

A study released by the U.S. Center for Disease Control and Prevention (CDC) and the Indian Health Service (IHS) in 2009 found that the death rate among Native peoples in the U.S. of complications from the H1N1 swine flu was four times that of the general population. The IHS attributed those high numbers at that time to obesity, diabetes, and overcrowded housing.

RELATED: IHS prepared for H1N1

Kedzierska noted that while determinants such as overcrowded housing will increase infections, genetics is the driver. “It depends on how a person deals with the infection. I think this would be true for any influenza virus, or new virus to which we don’t have antibodies.”

The researchers are at work to find ways to boost T-cell immunity in Indigenous communities in order to propose a vaccine that would provide some protections to Australian Indigenous populations. “It’s really important to understand if we have any vaccine it needs to be tested to make sure that it works for everyone,” Kedzierska said. “We need to make tailored vaccines.”

Kedzierska said every government should be aware when there is a newly emerging virus to make sure that their Indigenous population is protected. She expressed great interest in collaborating with U.S. researchers, and as well welcomes queries from Native Americans interested in working with their researchers. Reach Professor Kedzierska at kkedz@unimelb.edu.au.

H7N9 emerged in China in March 2013. China reported some mild cases, but most patients have had severe respiratory illness, with about one-third resulting in death. Canada reported the first case in the Americas of another strain of avian influenza, or bird flu called H5N1 in early January, in a traveler who had recently returned from China.

The IHS flu website at http://www.ihs.gov/flu/ recommends the best way to prevent the flu is by getting vaccinated each year, which can keep you from getting sick and keep you from spreading the flu to children and elders—those who can get very sick from flu.

RELATED: Indian Health Service launches influenza surveillance website

Visit the CDC’s Flu website at www.flu.gov for information on flu, flu vaccines, anti-virals and other flu-related information. And here’s advice for Parents on Talking to Children about the flu.

RELATED: Rate of Flu Shots Among American Indians among lowest in U.S.

You need to be logged in in order to post comments
Please use the log in option at the bottom of this page