Safety of Pandemic Vaccines

Safety Questions

Are pandemic vaccines safe? | Safe for pregnant women? | Safe for children?

Outcomes of studies completed to date suggest that pandemic vaccines are as safe as seasonal influenza vaccines. Side effects seen so far are similar to those observed with seasonal influenza vaccines.

What about safety for pregnant women?

To date, studies do not show harmful effects from the pandemic influenza vaccine with respect to pregnancy, fertility, or a developing embryo or fetus, birthing or post-natal development. In view of the elevated risk for severe illness for pregnant women infected by the new influenza, in clinical studies, pregnant women are a group that should be vaccinated against infection, as supplies allow.

Recent studies show that infected pregnant women have a 10 times higher chance to require hospitalization in intensive care units than infected persons in the general population, and 7% to 10% of hospitalized cases are women in their second or third trimester of pregnancy. The benefits of vaccination far outweigh the risks.

Additional studies on pregnant women following immunization are continuing.

What about my child's safety from a reaction?

The most frequent vaccine reactions in children following influenza immunization are similar to those seen after other childhood immunizations (such as soreness at the injection site, or fever). A child's health care provider or vaccinator can advise on the most appropriate methods for relief of the symptoms. If there are concerns about a child's safety from a reaction, consult a health care provider as soon as possible. Please note that a child may suffer from a condition not related to immunization, which coincidentally developed after vaccination.

Testing and Approval

What kind of testing is done? | Who approves pandemic vaccines?

What kind of testing is being done to ensure safety?

Because the pandemic virus is new, both non-clinical and clinical testing is being done to gain essential information on immune response and safety. The results of studies reported to date suggest the vaccines are as safe as seasonal influenza vaccines. However, even very large clinical studies will not be able to identify possible rare events that can become evident when pandemic vaccines are administered to many millions of people.

WHO advises all countries administering pandemic vaccines to conduct intensive monitoring for safety and report serious adverse events.

Who approves pandemic vaccines for use?

National authorities for medicines approve (or license) pandemic influenza vaccines for use. These authorities carefully examine the known and suspected risks and benefits of any vaccine prior to its licensing. Expedited regulatory processes in some countries have helped to license the new vaccine in a timely manner. However, the testing and manufacturing processes for the new vaccines are similar to seasonal influenza vaccines to ensure quality and safety.

Side Effects

What are the expected side effects? | Have all the possible side effects been identified?

What are the expected side effects of the new vaccines?

Some side effects can be associated with influenza vaccination. How often they result depends on the type of vaccine, how it is administered, and the age of the vaccine recipient.

There are two main types of vaccines: one is manufactured with inactivated viruses, the other uses live viruses.

Inactivated vaccines, administered by injection, commonly cause local reactions such as soreness, swelling and redness at the injection site, and less often can cause fever, muscle- or joint- aches or headache. These symptoms are generally mild, do not need medical attention, and last 1 to 2 days. Fever, aches and headaches can occur more frequently in children compared to elderly people.

Rarely, such influenza vaccines can cause allergic reactions such as hives, rapid swelling of deeper skin layers and tissues, asthma or a severe multisystem allergic reaction due to hypersensitivity to certain vaccine components.

Live vaccines are given via a nasal spray, and can commonly cause runny nose, nasal congestion, cough, and can less frequently cause sore throat, low grade fever, irritability and head- and muscle- aches. Wheezing and vomiting episodes have been described in children receiving live influenza vaccines.

Have clinical studies identified all the possible side effects?

Again, even very large clinical studies will not be able to identify possible rare events that can become evident when pandemic vaccines are administered to many millions of people. These can only be assessed when a vaccine is in widespread use.

Clinical trials often provide safety information for the general population. Additional monitoring of some special groups of vaccine recipients is necessary to gather specific safety information.

Additional and comprehensive monitoring efforts of the pandemic influenza vaccine are being planned as they are being used by more and more people around the world.

WHO advises all countries administering pandemic vaccines to conduct intensive monitoring for safety, and report adverse events.

Adverse Events

Have their been anyreported? | How should they be reported? | What happens when they are reported?

Have their been any reports of serious reactions, or adverse events, to pandemic vaccines?

As of late October, there is no indication at this stage that unusual adverse events are being observed after immunization, according to clinical trials and adverse event monitoring during deployment of vaccines in early introducer countries. The need for continued vigilance and regular evaluation by health authorities is ongoing.

How should serious reactions to the vaccines be reported?

Reports of serious adverse events, and those raising concerns, should always be submitted to national authorities. So far, reports of potential adverse events following immunizations have been well notified to authorities.

What happens when an adverse event is reported?

At the national level, individual reports are scrutinized for completeness and possible errors. In some instances, reports need to be validated and additional details must be checked. Reports are analysed for findings that are expected or appear more frequently than expected. If an analysis indicates a potential problem, further studies and evaluation are conducted and all relevant national and international authorities are informed. Decisions for appropriate measures are then made to ensure continuing safe use of the vaccine.

Risks falsely associated with vaccines

Will pandemic vaccines contain thiomersal? | Are adjuvants a health risk? | Can they cause chronic diseases? | Can they cause GBS? | How can a repeat of the 1976 experience be avoided?

Will pandemic vaccines contain thiomersal, which some believe is a risk to health?

Thiomersal is a commonly used vaccine preservative to prevent vaccine contamination by bacteria during use. Inactivated vaccines will contain thiomersal if they are supplied in multi-dose vials. Some products can have ''traces" of thiomersal when the chemical is used during the production process as an antibacterial agent, which is later removed during the purification process.

Thiomersal does not contain methyl mercury, which is a naturally-occurring compound and whose toxic effects on humans have been well studied. Thiomersal contains a different form of mercury (i.e. ethyl mercury, which does not accumulate, is metabolized and removed from the body much faster than methyl mercury).

The safety of thiomersal has been rigorously reviewed by scientific groups. There is no evidence of toxicity in infants, children or adults, including pregnant women, exposed to thiomersal in vaccines.

Why do some pandemic influenza vaccines contain adjuvants and others don't?
Are vaccines with adjuvants a health risk?

Adjuvants are substances that enhance the immune response in vaccines and can make them more effective. They have been used for many years in some vaccines. Scientific data support the safety of adjuvants in pandemic influenza vaccine production.

Some seasonal influenza vaccines that are intended for people known to have poor immune responses to immunization contain an adjuvant. Some pandemic vaccines contain an adjuvant to reduce the amount of virus antigen to be used (an antigen is a substance capable of stimulating an immune response).

Manufacturers decide whether a product is formulated with or without an adjuvant. Adjuvants used with pandemic influenza vaccines are already licensed for use with other vaccines (e.g. hepatitis B, seasonal or pandemic influenza vaccines, or others), and have a safe track record.

Can influenza vaccination cause chronic diseases?

Current evidence does not indicate that seasonal influenza or pandemic influenza vaccines, or any other vaccine against novel human influenza viruses, either induce or aggravate the course of chronic diseases in vaccine recipients. Careful assessment is required to clarify if adverse events that occur after vaccination are actually caused by an influenza vaccination.

Can influenza vaccination cause Guillain Barré syndrome (GBS)?

Guillain Barré syndrome (GBS) is a rapidly developing, immune-mediated disorder of the peripheral nervous system that results in muscular weakness. Most people recover completely but some have chronic weakness. It can develop following a variety of infections, including influenza. In people who have been immunized with available vaccines, the frequency of GBS usually is the same as in unvaccinated people. Extensive studies and data analysis of influenza vaccines have only found a well established causal association with the 1976 vaccine that contained an H1N1 swine-influenza-like virus. No other clear association has been found with either seasonal or other pandemic influenza vaccines.

How can a repeat of the 1976 swine flu vaccine complications (Guillain-Barré syndrome) experienced in the United States of America be avoided?

During the 1976 influenza vaccination campaign, about 10 persons per million vaccinated persons developed GBS.

The reason why GBS developed in association with that specific vaccine has never been firmly established. The potential for the development of a similar risk with future vaccines can never be totally excluded. However, pandemic influenza vaccines are manufactured according to established standards, and are similar to recent well-studied influenza vaccines that have shown no association with GBS. Surveillance after vaccines have been sold (post-marketing surveillance) is being conducted to look for potential developments of serious adverse events. Safety monitoring systems are an integral part of strategies for the implementation of the new pandemic influenza vaccines.

Resources

Notice of Decision for AREPANRIX H1N1 Vaccine
On October 13, 2009, an Interim Order was issued by the Minister of Health at the request of the Public Health Agency of Canada to allow the authorization for sale of a vaccine for the novel Influenza A H1N1 virus in response to the influenza A H1N1 pandemic.

The H1N1 vaccine race: Can we beat the pandemic?
Canada proudly claims to be the first nation with an influenza pandemic plan - a response, in part, to the lack of vaccine during the 1976 swine flu scare. We are told that there is a guaranteed supply of pandemic vaccine from a domestic source. But this is only the first step. The bigger issue is: Will we be able to immunize vunerable populations in time? Under the current plan, the answer is "No". Vaccines must pass a regulatory process for licensing, and Health Canada, the licensing authority, has decided to treat this virus like a new subtype rather than a variant H1N1 strain, requiring a more extensive review and a slower rollout.

Arepanrix [pdf]
Arepanrix product information leaflet by GSK.

Pandemrix (UK) [pdf]
Pandemrix product information leaflet by GSK.

A Perspective on the 1976 Swine Influenza Experience: Lessons Learned [pdf]
By Karen Midthun, MD, Deputy Director, Center for Biologics Evaluation and Research, FDA

2009 H1N1 Influenza Vaccine Q and A - CDC (US)
Questions and answers related to the 2009 H1N1 Influenza Vaccine from the US Centers for Disease Control and Prevention.

Ingredients of Vaccines - Fact Sheet - CDC (US)
Chemicals commonly used in the production of vaccines include a suspending fluid (sterile water, saline, or fluids containing protein); preservatives and stabilizers (for example, albumin, phenols, and glycine); and adjuvants or enhancers that help improve

Mercury and Thimerosal - CDC (US)
Information about Thimerosal from the US Centers for Disease Control and Prevention. Since 2001, with the exception of some influenza (flu) vaccines, thimerosal is not used as a preservative in routinely recommended childhood vaccines.

Frequently Asked Questions About Thimerosal - CDC (US)
Until 1999, vaccines given to infants to protect them against diphtheria, tetanus, pertussis, Haemophilus influenzae type B (Hib), and Hepatitis B contained thimerosal as a preservative.

ALERT Canadians: Toxic Ingredients in the Arepanrix H1N1 Vaccine Harm Your Health
This report is designed to inform you how the risks outweigh the benefits of the vaccine. It will demonstrate how the Health Canada assessment is flawed and contradictory to established research on the detrimental health effects of the vaccine ingredients

The vaccines are far more deadly than the swine flu
Mass vaccinations is a recipe for disaster Dr. Mae-Wan Ho and Prof. Joe Cummins. This report has been submitted to Sir Liam Donaldson, Chief Medical Officer of the UK, and to the US Food and Drug Administration.

Thimerosal in Vaccines - FDA (US)
In the following pages, a discussion of preservatives, the use of thimerosal as a preservative, guidelines on exposure to organomercurials (primarily methylmercury), thimerosal toxicity, recent and future FDA actions, and the conclusions of the Institute

Thiomersal and vaccines - Global Advisory Committee on Vaccine Safety
In 1999, concerns were raised in the United States of America about exposure to mercury in vaccines. This was based on the realization that the cumulative amount of mercury in the infant immunization schedule potentially exceeded the recommended threshold.

Thimerosal in Vaccines - NIAID (US)
In July 1999, U.S. Department of Health and Human Service agencies, The American Academy of Pediatrics, and vaccine manufacturers agreed that thimerosal should be reduced or eliminated in vaccines as a precautionary measure and to reduce exposure to mercu

Safety of pandemic (H1N1) 2009 vaccines - WHO
Global Alert and Response (GAR) from the World Health Organization answers questions about the safety of pandemic 2009 H1N1 vaccines.

Intranasal vaccines and the occurrence of Bell's palsy
In October 2000, an inactivated intranasal flu vaccine (virosome formulated and adjuvanted by heat labile enterotoxin of Escherichia coli) was licensed in Switzerland.

Vaccine Concerns - Adjuvants and Ingredients Resources - Immunization Action Coalition
The Immunization Action Coalition (IAC) works to increase immunization rates and prevent disease by creating and distributing educational materials for health professionals and the public that enhance the delivery of safe and effective immunization services.

US Dept of Defense Novel Influenza A (H1N1) Vaccine Program
Novel Influenza A (H1N1), was first recognized in April 2009. Since that time, it has spread both nationally and internationally.

US Dept of Defense Anthrax Vaccine Immunization Program
The Official DoD Anthrax Vaccine Immunization Program (AVIP) Web Site. Your definitive source for information about anthrax - the disease, the threat, the safety and effectiveness of the vaccine and the implementation of the Anthrax Vaccine Immunization Program.

Antibodies to Squalene in Gulf War Syndrome [pdf]
Armed Forces Epidemiological Board. Recommendations regarding review of the paper �Antibodies to Squalene in Gulf War Syndrome by P. B. Asa, Y. Cao and R. F. Garry. 11 Jul 2000.

Biological Products; Bacterial Vaccines and Toxoids; Implementation of Efficacy Review [pdf]
20 January 1991, during Desert Storm, under orders, our company was injected with a single dose 'SECRET' Anthrax vaccine. This vaccine likely contained Squalene, an oil adjuvant, illegal in the United States for human use.

This information should not be used as a substitute for the medical care and advice of your physician.
There may be variations in treatment that your physician may recommend based on individual facts and circumstances.

For more user submitted links please visit the Health and Wellbing category topic: H1N1. For user submitted downloads please visit the Health, Fitness, Wellbeing section and we also have health and wellbeing documents related to H1N1 and the vaccines available here: http://windsorlive.com/docs/health.php. Be sure to join our interactive Community Discussion Forum to share your experiences and other resources about pandemic influenza. We are also looking for contributors and sponsors for this resource. Please contact us if you can help us provide this valuable online resource for our community.