Suspected adverse reactions to Panvax® reported to the TGA 30 September 2009 - 30 April 2010
17 June 2010
The national immunisation program with Panvax® began on 30 September 2009. The TGA has been closely monitoring any side effects from the use of the vaccine.
As at 30 April 2010 a total of 1773 suspected side effects have been reported to the TGA following vaccination with Panvax® in Australia. To that date approximately 8.7 million doses of Panvax® had been distributed in Australia and over 370,000 doses of Panvax Junior®. The great majority of reported side effects have been mild and common problems such as headache, gastrointestinal upset, soreness, swelling, or redness at the injection site. Most of the side effects that have been reported are well recognised and listed in the Panvax® Product Information. Of the suspected side effects reported, only 156 related to Panvax Junior®, and the majority of these reports were of fever (129) and/or vomiting (75).
The TGA's assessment remains that Panvax® is a safe, effective vaccine for prevention of the H1N1 influenza.
Further information about the vaccine may be found at Health Emergency.
Common side effects reported to date
Common side-effects reported following Panvax® administration are shown in the table.
| Suspected adverse reaction | Number of reports for PANVAX®* |
|---|---|
| Nausea, vomiting or diarrhoea | 589 |
| Headache | 333 |
| Fatigue, lethargy, general weakness | 389 |
| Fever | 400 |
| Cough, runny nose or sore throat; flu-like symptoms | 368 |
| Injection site reaction | 345 |
| Pain (including muscle or joint pain; excluding injection site pain) | 388 |
* The sum of the common side effects exceeds the total number of reports because each report can contain more than 1 reaction, for example, an injection site reaction and flu-like symptoms.
Due to concerns regarding a possible association between influenza vaccines and the development of a rare condition known as Guillain-Barré syndrome (GBS), the TGA continues to closely monitor the rate of GBS in the Australian community during the Panvax® immunisation program.
Based on all evidence available, and following advice from its independent expert advisory committees, the TGA has concluded that there is no evidence of an increased rate of GBS in people receiving Panvax® compared with that normally seen in the community.
In Australia there are approximately 100 new cases of GBS every three months. Viral and bacterial infections, especially food poisoning and acute respiratory tract infections are the commonest precursors to GBS. In the six months of the Panvax® immunisation program the TGA has received 10 reports of GBS in people who had received the vaccine.
Similar analyses of data relating to GBS by overseas medicines regulators including in the US, Canada and Europe have concluded that there is no evidence of an increased rate of GBS in people receiving the H1N1 influenza vaccine. The World Health Organization has also confirmed that although some cases of GBS have been reported after receipt of pandemic (H1N1) 2009 vaccines, the evidence to date is reassuring, with no increase in reporting rates above what is expected based on background rates1.
An important category of possible reactions to any vaccine is allergy. Severe allergic reactions, such as anaphylaxis, may require adrenaline injections or other treatment, which is the reason why all persons providing vaccines must have the necessary drugs and equipment available. The occurrence of anaphylaxis and allergic reactions is not predictable and can occur in anyone regardless of whether they have a previous history of allergy or not. Anaphylaxis is a rare event but healthcare professionals and patients should be aware of its possible occurrence.
As at 30 April 2010, the TGA had received 10 reports of possible anaphylaxis following vaccination with Panvax®. The TGA, together with its expert advisory committees, has thoroughly investigated the details of these suspected cases of anaphylaxis. Using the Brighton Collaboration criteria for defining anaphylaxis2, the TGA, following advice from its expert advisory committees, has concluded that, based on distribution figures for Panvax®, the current observed rate of anaphylaxis is within the range expected for anaphylaxis post-immunisation. All cases reported to the TGA to date have either been treated appropriately or have resolved without treatment.
As at 30 April 2010 the TGA had received 27 reports of convulsions of which 16 reports were febrile convulsions in children with three of these in association with the administration of other vaccines. Convulsions are known to occur at a rate of between 1 in 1,000 and 1 in 10,000 people vaccinated with influenza vaccines. As there have been approximately 8.7 million doses of Panvax® and Panvax Junior® distributed the rate of convulsions observed is less than might be expected based on experience with other influenza vaccines.
The TGA continues to work closely with its international regulatory partners and the World Health Organization to detect and respond to any safety signals that may emerge as the H1N1 influenza vaccine is used around the world.
Reference
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- Rüggeberg JU, Gold MS, Bayas J-M, Blum MD et al. Anaphylaxis: Case definition and guidelines for data collection, analysis, and presentation of immunization safety data. Vaccine 2007; 25: 5675-5684.
- WHO Weekly epidemiological record, No. 5, 2010, 85, 29–36 (pdf,749kb) <http://www.who.int/wer/2010/wer8505.pdf>
How to report a suspected side effect to Panvax®
Healthcare practitioners and consumers are encouraged to report any suspected adverse events following immunisation with Panvax® by using the online reporting form <http://www.tga.gov.au/problem/medicines.htm> available from the TGA website.