Influenza is extremely contagious and often got from the air because it is an airborne infection. While the flu vaccine has had some success, researchers are at a loss to know which strain of influenza will take predominance in a particular season and make the vaccine tailored for it. As the flu vaccine is effective only for certain strains of flu, it is quite easy to get another strain, even if you have taken your flu shot, which is effective only against H3N2, H1N1 and B viruses.
Why is the disease often referred to as swine flu or bird flu or avian flu?
This is because specific strains often originate from birds or animals, go on to the people who work on them and mutate so then they readily find human hosts. Influenza is different from common cold and cough, though early symptoms may be similar. However, influenza is a more serious illness and can lead to various complication, including pneumonia and even be fatal – the disease can has caused more 50,000 fatalities in a year (reports available for 2011 for influenza and pneumonia) according to CDC. What is worse is that often the flu virus mutates so rapidly and with very severe consequences – the swine flu (H1N1) and SARS being prime examples. Because of increased air travel the virus spreads rapidly worldwide.
Medical researchers at Seattle BioMed collaborating with people at the University of California, San Diego School of Medicine, St. Jude Children’s Research Hospital and the University of Washington, have just recently published their findings in CELL on how critical molecules regulate both the induction and resolution of inflammation during flu infection.
The research studied how different flu viruses affect the body. The researchers – Aderem and Vincent Tam, PhD and Oswald Quehenberger, Ph.D., and Edward Dennis, Ph.D. – focused on lipid components and the host-pathogen interaction. It was known that lipid mediators played an important role in the body’s inflammatory response. The researchers adopted a systems approach, using computational tools to integrate the study of genes, proteins and lipids. This comprehensive approach had never been applied to this kind of infection earlier.
They studied 141 different lipid metabolites along with two different flu strains to see how the process worked. The lipid metabolites are a crucial element in host and pathogen interaction. They found that the milder H3N2 strain caused a pro-inflammatory response that was later followed by an anti-inflammatory response. The severe H1N1 virus produced both pro and anti inflammatory responses that were overlapping. This gave the researchers a new weapon in the fight against flu by hopefully revealing new drug targets that would increase immunity among patients.
New flu dangers
Unfortunately, flu still claims lives and mutates very rapidly and does not wait for research to catch up with it. Since March 2013, more than 37 people have died in China due to a new bird flu virus. The H7N9 strain can easily spread and mutate even further and there are fears of an epidemic. According to researchers led by Yoshiro Kawaoka of the University of Wisconsin-Madison this particular virus can be potentially extremely dangerous. WHO has also warned about a global pandemic.
While the H1N1 swine flu virus targeted those younger than 25, the H7N9 virus attacks older people, especially those over 60 and mostly male. While there are a number of anti-virals and other flu specific medicines, there is no guarantee that they will work against the new strains. Often the viruses develop resistance to current available drugs and that is why CDC advocates flu shots. However, flu shots often don’t work effectively for many people since the elderly have reduced immunity so don’t produce enough antibodies to counter infections.
What is even worse that influenza often starts off with minor symptoms and it is only when they persist that people get tested for virulent strains of flu, which makes treatment all the more difficult and, at time, less effective.
The importance of a universal flu vaccine
The flu shots are effective only around 60 percent of the time. When medical research points to the exact viruses that cause flu and be able make a vaccine to prevent it, then there will be a turnaround in the statistics. This research hopes to understand the way flu viruses interact with the human response system so that immune systems can be made stronger.
CDC asks everyone to get flu shots, even if they are not completely effective, because they do reduce the incidence of the disease to some extent. And people, who are more vulnerable such as senior citizens and children, specially need to get their shots.
There is need for a universal flu vaccine that will work against all strains of flu and give better immunity. Unfortunately, researchers have not made much headway against this because the flu virus mutates in such a way – subtly changing their surface proteins constantly – that the human immune system cannot act against them. A universal flu vaccine would be able to provoke a stronger response from the body and also act against different flu strains. It may also not need to be given yearly as current flu shots have to be. While this may increase the price of the vaccine, if it actually works the way it should, it would save a lot of money in terms of productive days lost due to illness and of course avoid fatalities.
New York Times
National Institute of Allergy and Infectious Diseases