PURPOSE
To determine whether regular seasonal influenza vaccination has any effect on the risk of developing influenza due to the 2009 pandemic H1N1 virus.
- The pandemic strain of influenza is very different from the usual seasonal influenza viruses
- Vaccines made to protect people from usual strains of seasonal influenza would not be expected to protect people from this virus. Unexpectedly, four studies in Canada indicate that people who got the seasonal influenza vaccine last fall are actually a bit more likely - about 2 times more likely - to see a doctor for pH1N1 infection than unvaccinated people of similar age. The basis for these unexpected observations is not known. No similar effect was seen in studies in the USA or Australia.
- We believe that it is important that we find out whether this effect is real, so that we can better understand the effect of influenza vaccination in general, so we can ensure that we can make the best recommendations for influenza vaccination programs for 2010, and so that we can more effectively prepare for the next pandemic. For this reason, you are being asked to participate in this study.
PROCEDURES
If you wish to participate in the study, you will have to:
- Also agree to participate in the influenza Cohort Study
- Be randomized to receive either the regular 2009 seasonal influenza vaccine or a placebo injection of sterile normal saline (salt) solution. Half of the participants in the study will receive influenza vaccine, and half will receive placebo.
- At the end of November, the study will contact you about the status of the study. Based on the best available information at the time, the study will make a recommendation to you about whether or not you should receive the seasonal influenza vaccine if you were randomized to the placebo injection. If you choose to be vaccinated with the seasonal vaccine, the study will offer vaccine to you.
When you enroll in the study, you will be given a supply of antiviral medication, for treatment of influenza should you become infected. Because antivirals are most effective if taken early after the onset of symptoms, and because it is sometimes difficult for people with influenza to get to their pharmacy to fill a prescription, we are giving you these to keep and use if necessary. If you develop an illness with sudden onset, fever and cough, or any illness that you think might be influenza you should call the study office, and discuss whether you should start taking the medications. Instructions to help you understand when and if to start taking the medication are included in your enrolment package.
DURATION OF STUDY AND NUMBER OF VISITS
This study will not add any time to your participation in the influenza cohort study. You will need to make at least one additional study visit, to discuss your participation, and to receive the study injection. This visit will take 20-60 minutes, depending on how many questions you have before you decide about study participation.
RISKS
Influenza vaccination and injections of placebo may be associated with soreness or redness at the injection site. These reactions are usually mild. Allergic reactions to vaccines, including urticaria (hives) and anaphylaxis (severe allergic reaction) are rare, but can occur. Two other very rare adverse events of influenza vaccination have been described. Oculo-respiratory syndrome is redness and irritation of the eyes, and swelling of the face that starts within a few hours of vaccination, and lasts a few hours. It occurs in about 1 in 10,000 vaccinations, and is not dangerous, but may be frightening. Guillan Barre syndrome is a neurologic disease that appears to occur at a rate of about 1 per million vaccinations; it can also complicate influenza.
If you are randomized to receive the seasonal vaccine, you may be at increased risk of infection due to pH1N1. This risk, if it exists, appears to be about a 2 fold increase. pH1N1 infection in healthy adults is usually not serious, but can occasionally be. As part of the study, you will be offered diagnosis and treatment promptly, and we believe that this will effectively prevent serious complications; however, a very small risk may be present. Similarly, if you are randomized to NOT receive the seasonal influenza vaccine, and the regular 2009/10 influenza season starts early, you will be at some risk of getting seasonal influenza, which can also occasionally be serious. Weekly emails from the study will keep you updated on influenza developments, and you may choose to get either vaccine at any time after the study starts.
Please see the instructions which accompany your antiviral medication for the potential risks associated with this medication.
BENEFITS
- There are not direct benefits to you from participating in the study. Depending on which injection type you are randomized to, you may be protected from the risk of seasonal influenza.
- We hope that the information from this study will help us to better protect people from influenza in the future.
PARTICIPATION
Your participation in this study is voluntary.
EXPENSES ASSOCIATED WITH PARTICIPATING IN THE STUDY
- You will be not have to pay for any of the procedures involved with this study.
- You will be provided with $25 per study visit to cover the costs of travel and parking, and compensate you partially for your time.
Study Investigators:
Dr. Allison McGeer, Mount Sinai Hospital, Toronto, Ontario
Dr. Brenda Coleman, Mount Sinai Hospital, Toronto, Ontario
Dr. Natasha Crowcroft, Ontario Agency for Health Protection and Promotion, Toronto
Ms Karen Green, Mount Sinai Hospital, Toronto, Ontario
Dr. Kevin Katz, North York General Hospital, Toronto, Ontario
Dr. Mark Loeb, Hamilton Health Sciences Centre, Hamilton
Dr. Shelly McNeil Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia
Dr. Matthew Muller, St. Michael's Hospital, Toronto, Ontario
Dr. Andrew Simor, Sunnybrook Health Sciences Centre, Toronto, Ontario
Sponsor: This study has been initiated by a group of independent investigators. GlaxoSmithKline Inc. is providing funding for this study.
