12 Nov 2009

Doubts about vaccine safety

The Italian consumers organization Codacons has asked the Ministry of Health to prove the safety of the flu vaccine, the Focetria vaccine made by Novartis. Codacons doubts that  a producer can make and test a flu vaccine in four months. Another point is the use of the MF59C.1 adjuvant, containing squalene. In Italy Codacons is a well known union, but in such a scientific matter it's a bit confused (and confusing).
The European Medicines Agency (Emea) has already explained the procedure of the ‘mock-up’ vaccines: in the first step Emea has evaluated a flu vaccine containing a different strain, the H5N1, and when the WHO declared the pandemic, the vaccine producer has replaced the strain in the mock-up vaccine with the pandemic H1N1 strain.
The second issue is more complex. "Clinical trials with MF59C.1 adjuvanted H5N1 vaccine have shown that the vaccine is adequately immunogenic in children older than 6 months up to 17 years with an acceptable safety profile." wrote Emea about the safety of the adjuvant system in children. So, it's ok for children.

More murky is the evidence of safety in pregnant women. Emea wrote:
"The non-clinical program included studies where the MF59C.1 adjuvant was given alone, or in combination with non-influenza antigens. This included specifically designed studies with administration before pregnancy, at the time of mating, as well as later during pregnancy in rabbits. It was shown that the doses of MF59C.1 applied did not induce reproductive toxicity for the dam or the foetuses. Experience with these adjuvants in pregnant women is very limited. In the pregnancy clinical database of Novartis, a limited number of pregnancies occurred in females of childbearing potential exposed to at least one dose of a MF59C.1 adjuvanted vaccine (either influenza vaccine or not). No occurrence of congenital abnormalities was reported, but the experience is too limited to draw conclusions."
So, it looks like Codacons could be right about the vaccine safety in pregnant women. The adjuvant has been tested in rabbits, not women . On the other hand, one should consider the risk of becoming infected while pregnant. So, it's up to every woman to choose. But the Italian Focetria leaflet doesn't help. Strange enough, the Italian leaflet ("Tell your doctor if you may be pregnant, plan to become pregnant. You should discuss with your doctor whether you should receive Focetria) is less clear from the English Focetria leaflet ("Tell your doctor if you are pregnant, think you may be pregnant, plan to become pregnant. You should discuss with your doctor whether you should receive Focetria).

1 comment:

  1. The 2009 H1N1 swine flu pandemic resulted in millions of individuals getting ill worldwide. The outbreak of the H1N1 swine flu was originally established in the month of April in the year 2009. Scientists and medical professionals established that the H1N1 swine flu was an interesting combination of genes from the swine virus, the avian virus, and a human virus. It was established that the original outbreak occurred in an area of Mexico called Veracruz.

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