Should I get the H1N1 shot?

Provinces and territories have embarked on Canada's largest-ever mass immunization campaign. But with poll after poll showing less than half of Canadians willing to roll up their sleeves, and doubts swirling about the safety of the H1N1 pandemic vaccine, public health officials have a tough slog ahead in debunking the myths. Canada's chief public health officer, David Butler-Jones, expressed frustration at the anti-vaccine sentiment. Canadians, he said, have a choice: Protect themselves with a safe and effective vaccine, or risk severe disease and even death. "We have the potential to prevent tens of thousands of hospitalizations and thousands of deaths by a simple process of taking advantage of the vaccine that we have," Dr. Butler-Jones said Monday.

1. Will the vaccine give you the flu? AND what about side effects?

The vaccine cannot give you influenza, because it doesn't contain a live virus. In fact, it contains antigens that trick the immune system into thinking it has been attacked by the H1N1 virus so it produces antibodies. It takes about a week to 10 days for immunity to develop after being vaccinated. While some people are scared or nervous about getting a needle, after the initial jab the side effects are similar to those seen with seasonal-flu vaccines, including headaches and sore muscles.

2. It's a new vaccine. But has it been tested enough?

Health Canada says that, based on the results of thousands of clinical trials around the world, it is satisfied the vaccine is safe. And the adjuvant, a chemical product that boosts the immune response, has been tested on thousands with the H5N1 avian flu drug and proven effective, the regulator says. The vaccine confers more than 90-per-cent immunity in healthy adults, more than the seasonal flu vaccine. Researchers cannot do studies in millions of people before licensing a vaccine, which would be too time-consuming during a pandemic. Post-licensing surveillance, in which people report their side effects, will be conducted in Canada.

3. Can you trust the adjuvant?

Canada's vaccine uses an adjuvant which consists of squalene (shark liver oil), DL-alpha-tocopherol (vitamin E) and polysorbate 80 (an emulsifier also used in ice cream). There were claims that squalene, part of the adjuvant used in the anthrax vaccine, was to blame for Gulf War syndrome, but the evidence just wasn't there. Claims that mercury in vaccine causes autism have also been debunked. The amount of mercury in a typical vaccine is less than in a can of tuna. The adjuvant used in Canada has been tested with the bird flu vaccine and there was no negative response to it.

4. Should you get the vaccine if you're pregnant?

Pregnant women are one of the most at-risk groups. Their chances of getting very sick and potentially dying from swine flu are four to five times higher than for non-pregnant women, according to experts, and there is also a risk to the fetus. Michael Gardam, director of infectious diseases prevention and control for the Ontario Agency for Health Protection and Promotion, noted recently that there is no evidence that any component of this vaccine is harmful to the fetus. Women more than 20 weeks pregnant and those in earlier stages of pregnancy with a history of chronic illnesses should consider getting the adjuvanted vaccine, until the unadjuvanted vaccine is available, public health officials say.

5. What should you do to prevent the spread of H1N1?

• Frequent hand-washing with soap and water curbs the spread of germs;
• Cough into your arm and stay home if you're sick;
• Antiviral drugs, such as Tamiflu, will help fight off the virus. But they should be prescribed by a doctor and used for treatment, not as a preventive measure;
• Don't all rush to get the vaccine at the same time. The vaccine is slowly trickling in to provinces and territories, and health officials want pregnant women, adults with chronic conditions, health-care workers, people living in remote places and schoolchildren to be first in line.

6. Should you get vaccinated?

Consider this: 5,000 people have died worldwide, and hundreds of thousands of people have been infected with H1N1. The most recent death in Canada was a preteen girl from Cornwall, Ont., who had no pre-existing medical conditions. True, there have been few H1N1 deaths overall in Canada, but this virus attacks the young, unlike the seasonal flu, which burdens the elderly. Adults get one dose; children between the ages of six months and nine years get two half-doses at least 21 days apart.