The search for universal flu vaccine — who will win the race?
Every year, many of us get flu shots in preparation for the flu season. Imagine an all-in-one flu shot that you only need to get once. It may not be too far in the future for this to happen.
One of the most effective strategies in the prevention of seasonal flu epidemics is vaccination. The development of influenza vaccines began soon after the isolation of human influenza A virus in 1933 and continue to be developed each year. The production of better flu vaccines is crucial in the prevention of flu pandemics, such as the one caused by H5N1 (or avian flu) that inflicted about 600 people worldwide as of last month, of which 60% of the cases were fatal.
The major challenge for the preparation of flu vaccines is the ever changing nature of flu viruses. Flu vaccines contain inactivated flu virus or parts of flu virus. By exposing our bodies to these harmless forms of virus, our immune system learns to recognize them and become ready to attack the real flu virus when we get infected by it. Currently, the most common parts of the flu virus that are used in vaccine are the proteins coating the outside of the virus. However, these outer coating changes (or mutates) rapidly, leading to the emergence of new strains of virus. Vaccine would be useless if it contained a strain of virus that is different from the strain circulating in the particular season. This poses challenge for guessing which strain to include in the seasonal flu vaccine each year. This is why it is necessary to make new vaccines every year, which contains flu strains of that particular season, and we need to be repeatedly immunized. Moreover, when new form of flu virus emerges, we are unprepared, resulting in a pandemic like the one we experienced in 2009 with swine-origin H1N1 flu virus.
In order to put an end to this guess work for annual flu vaccine production and our burden on getting flu shots every year, researchers are in search for universal flu vaccine – a vaccine that can provide protection against all strains of influenza viruses. This hunt is pursued by many pharmaceutical and biotechnology companies, as well as clinical and academic researchers. In fact, several vaccines are already in clinical trial to test for their effectiveness in humans.
One that might be a step faster than others is a flu vaccine called Multimeric-001 developed by Israeli pharmaceutical company BiondVax Pharmaceuticals. This vaccine contains nine segments of three flu viral proteins which are shared by more than 10,000 flu strains. Thus the goal is to provide protection against all strains of flu. In Phase I of clinical trial, the vaccine was tested on 60 healthy individuals and was shown to be safe and successful in inducing anti-influenza immunity. Now the vaccine is in Phase II of clinical trial to test on larger number of subjects, and the result should be revealed soon.
While waiting for the winner of the race for the hunt for universal flu vaccine, we can also help prevent the spread of flu by using precautions, such as washing hands frequently, coughing into sleeves, avoiding crowded area during flu season, etc.
Thank you for reading this post, and see you next week! 🙂
Moving towards a universal flu vaccine
Safety and Immunogenicity of Multimeric-001—a Novel Universal Influenza Vaccine
One step closer to universal influenza epitopes
Influenza vaccine immunology
Novel vaccines against influenza viruses
A universal influenza vaccine: where are we in the pursuit of this “Holy Grail”?
Research and development of universal influenza vaccines
Cumulative number of confirmed human cases for avian influenza A(H5N1) reported to WHO