H1N1 Vaccine: Potential Risks

The H1N1 swine flu vaccination campaign is due to begin in October for most of North America. However, as the conversation about the fall onset of swine flu is picking up, more and more people are being concerned over the risks associated with H1N1 vaccine.

The H1N1 vaccine is no different than any other vaccine out there in a sense that, like any vaccine, it will have some risks associated with it. First of all, the H1N1 vaccine that is being prepared right now contains live attenuated virus. That means egg embryos were used to grow live viruses which were than attenuated or weakened by a chemical or heat reaction, such that the virus is incapable of causing an infection, because part of its viral machinery is damaged or missing. So, even when the virus is injected into a human system, it will still build up the immune response, but won't do any actual damage. However, some viruses are notorious for fixing their DNA and reverting back to normal while in the human body. This is where the danger can lie -- what might end up happening is that a healthy person might be injected with disabled virus only for it to revert back to a fully functional, dangerous virus later on. Of course, the chance of a reversion happening is always negligible.

Another potential risk lies in how quickly the vaccine was assembled. From the time we found out about swine flu in May to administering the vaccine in October, scientists had to figure out the viral strain, code its DNA, create a vaccine, mass-produce it, and test it on animals and humans. Even with the modern advancements in medical technology, it is still an express way to make a vaccine, the whopping three billion doses of it.

The bottom line is that the H1N1 vaccine is new and had very limited testing done on it. Unlike established vaccines, like mumps, rabies or Hepatitis A that have been manufactured without much change for years, the H1N1 vaccine is brand new. Yes, it is being produced in accordance with an established template from previous years, but the virus is new to humans so the dangers associated are higher.

The World Health Organization (WHO) maintains that the H1N1 vaccine is just as safe as any seasonal influenza vaccine.

WHO did release a bit of a waiver, saying there is a possibility of "rare events that can occur when pandemic vaccines are administered to many millions of people." WHO does not specify what it means by "rare events," however. But, in fact, it makes sense for WHO not to, because no one can really tell what these "rare events" might be. 

The side effects from the actual injection of the vaccine are your typical soreness, swelling, redness, fever, headache, and muscle pains. But, these things are relatively minor. 

There has been some chatter online about the adjuvant chemicals used in the vaccine to enhance its effect. There has a particular concern about the potential use of squalene, which some say can lead to neurological disorders. However, previous studies have refuted the relationship between the use of squalene in anthrax vaccine and neurological damage.

In the end, any pandemic is a big gamble. So, while we may be trying to predict what the potential problems might be, many of the vaccine risks will have to be assessed as the vaccination campaign unravels.