Severe Flu Season Puts Spotlight on New Vaccine Developments and Existing Challenges
This year’s flu season started early and has been severe. By early January, more than 15,000 people had contracted the virus, which caused overcrowding at many local hospital emergency rooms. In one week alone, there were over 2,000 hospitalizations associated with the flu. So when the flu is bad, often there is increased interest in new developments to prevent illness associated with the influenza virus. A recent article in the MIT Technology Review titled “Why is the flu so relentless and how technology might help,” discusses several advancements.
New Vaccine Developments
Recently Approved Cell Culture Based Vaccine Manufacturing Options
On November 20, 2012, the Food and Drug Administration (FDA) announced that it approved the use of Flucelvax manufactured by Novartis to prevent seasonal flu in people over age 18. This approval was the first for a cell culture-based seasonal influenza vaccine in the United States. Instead of using the traditional chicken egg production method, Novartis propagates the virus in Madin Darby Canine Kidney (MDCK) cells. There are many advantages to using a cell culture-based manufacturing system for vaccines – it is quicker to manufacture, efficiently scalable and offers more control over the manufacturing environment. These advantages are particularly important in fighting a potential influenza pandemic. Please see our previous blog “A First – Cell Culture Based Seasonal Influenza Vaccine Approved by the FDA,” for more information.
This year another cell culture based vaccine was approved. On January 16, 2013, the FDA approved Flublok, manufactured by Protein Sciences Corporation. Flublok utilizes recombinant DNA technology and a baculovirus (insect virus) expression system. The insect cells are used to manufacture recombinant hemagglutinin, a flu virus protein. This technology offers similar advantages in that it can be used to manufacture influenza vaccines much faster than traditional egg based production. In addition, it doesn’t require availability of the influenza virus, just the genetic code.
Another benefit – both cell culture based vaccines offer an alternative for the millions of Americans who are allergic to eggs and are unable to receive any vaccine manufactured using egg-based production.
Universal Flu Vaccine Testing
Many researchers are currently working on a universal influenza vaccine that would eliminate the need for seasonal flu vaccines by attacking a part of the influenza virus that doesn’t mutate or change with different strains. If this type of vaccine is achieved it would effectively end the threat of a pandemic because effective vaccination would not rely on predicting which strains would be prevalent for that flu season. The goal would be to also effectively combat new mutations. There are several approaches being examined to accomplish this type of vaccine, including these examples:
- Dr. Sarah Gilbert at Oxford’s Jenner Institute is testing a universal flu vaccine that involves boosting T cell immunity instead of focusing on the creation of antibodies to the virus.
- A team of scientists at The Scripps Research Institute and Crucell Vaccine Institute has identified human antibodies that provide broad protection against both Influenza A and B strains. According to a press release on The Scripps Research Institute website “To develop a truly universal flu vaccine or therapy, one needs to be able to provide protection against influenza A and influenza B viruses, and with this report we now have broadly neutralizing antibodies against both,” said Ian A. Wilson, the Hansen Professor of Structural Biology at Scripps Research, who was senior investigator for the new study with Crucell’s Jaap Goudsmit and Robert Friesen.
- DNA-based influenza vaccines are also being developed that contain portions of the influenza virus’s genetic material. This material, when injected, causes cells in the body to make the proteins, which then activate the immune system against the virus.
The Challenge of Low Vaccination Rates
Perhaps the most pressing opposition to successful vaccination against the flu is that people don’t get vaccinated. The Washington Post presented a very interesting blog titled “Why 64.8 percent of Americans didn’t get a flu shot,” that provides interesting statistics and insight around seasonal flu vaccination behavior. As the title reveals, many Americans don’t get a flu shot even though it is widely available. The blog features an interesting poll about perceptions of the flu vaccine. In the poll, 28% reported, “I don’t need it.” It just isn’t as pressing or as dangerous as some other vaccines individuals do get. However, the flu can be deadly, particularly to those at risk, including children, the elderly, pregnant women, and those with compromised immune systems. Centers for Disease Control reports that over the past 31 years, seasonal flu deaths have ranged from 3,000 to 49,000 per season. Despite these facts, getting people vaccinated is a hurdle that has to be overcome regardless of the technology behind the vaccine.
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