Scientists are squabbling over the effect of virus inhibitor Tamiflu. While some say it is an important weapon in the battle against Mexican flu, others say this has never been proven.

The effect of Tamiflu has not been researched enough, says epidemiologist Luc Bonneux of the Netherlands Interdisciplinary Demographic Institute. He says there is no proof that the virus inhibitor prevents serious complications from Mexican flu. But Jaap van Dissel from the Leiden University Medical Centre is convinced that it works.

What bothers Mr Bonneux most of all is the so-called scientific research. In an article for the Dutch Journal of Medicine, he writes that one of the often-cited studies into Tamiflu's active substance, “oseltamivir”, was carried and paid for by the Swiss medicine manufacturer Roche. By coincidence, the same company which put Tamiflu on the market.

Unreliable
The Belgian epidemiologist thinks there is a lot wrong with the research. Mr Bonneux doubts whether the test groups in the Roche trial show enough similarities to be able to draw factual conclusions. He thinks Roche has presented the results in the most favourable light. He wants bigger and better studies to gain more certainty about the drug’s effectiveness. In addition flu patients seldom develop complications, like pneumonia, not even high-risk patients. Therefore treatment is unnecessary.

Difficult research
Jaap van Dissel, professor of infectious diseases at the Leiden University Medical Centre and a member of the Dutch Health Council, says Mr Bonneux is entitled to his own opinion. “Research into the effectiveness of Tamiflu is just difficult”, he says. Two groups of trial volunteers hopefully develop seasonal flu. One group is given medicine and the other is not, showing whether or not the medicine works. Ideally, “because flu symptoms do not always mean someone has flu,” says Professor Van Dissel. “If the trial volunteer does not have flu, Tamiflu doesn’t work either.”

The professor from Leiden believes Tamiflu is effective in the current pandemic. “In a situation like this, you know it is flu. Then it appears that 80 percent of people in close contact with the patient are protected. Especially if it is taken straight away. The quicker the better.”

Commotion
This is not the first time that Mr Bonneux has expressed his doubts about Tamiflu. In a commentary in the Belgian magazine De Tijd, he wrote earlier that it is only the pharmaceutical industry that profits from the medicine as remedy for mild flu, which H1N1 in fact is. The evidence that Tamiflu slows down the epidemic by a day, can, according to him, only be found in the “virtual world” of an obscure computer model.

”The telephone was red hot,” says Mr Bonneux, surprised by the commotion his article caused. “While I didn’t actually say anything new. When the US Food and Drug Administration (FDA) approved Tamiflu in 1999, it doubted its effectiveness.” The FDA considers the effectiveness of the medicine in people with a poor immune system or serious heart disease unproven.

Clear considerations
In addition Tamiflu is expensive, a relatively large number of people have to be treated to prevent infection and it only provides a limited amount of protection. “A preventive dose of antibiotics works better,” thinks Luc Bonneux. “The complications of flu can cause more problems than the actual disease itself. Pneumonia can be treated with antibiotics. Then Tamiflu doesn’t help at all.” Although, he does not deny that the medicine is useful for people in high-risk groups, such as the elderly and the chronically ill.

“That is precisely Dutch policy, so I do not see the problem,” says Professor Van Dissel. The Netherlands is much stricter than Great Britain for example, where Tamiflu can just be ordered over the Internet. “Here it is only people in high-risk groups who are given a prescription, and they always have to consult a doctor. When the patients are children a doctor should take the decision whether or not to prescribe the drug.”

Professor Van Dissel sees few alternatives. “We are not talking about a nasty bout of winter flu, this is a type of influenza which few people have developed immunity to. We know that a lot of people have to be treated to prevent the spread of the epidemic. Doing nothing is not an option. Mr Bonneux says the glass is half empty, we prefer to say the glass is half full.”

External Weblinks:

FDA report on Tamiflu

The Netherlands Interdisciplinary Demographic Institute

RIVM: Mexican Flu Dossier (in Dutch)

Profile of Prof. Jaap van Dissel