I refer to the letter Latest flu outbreak an American plot and a subsequent reply by Progress At Any Cost .

First of, I would like to correct a few statements by ‘Progress at Any Cost'. He is correct in saying that Tamiflu is not a vaccine. It is an antiviral drug which inhibits some viruses from ‘reproducing' (an inaccurate term to use, since they are technically not alive) within the host's body.

However to say that it is a drug extracted from star anise (bunga lawang) is akin to saying that ice cream is a dessert extracted from cows. It is a merely one of the raw ingredients for a lengthy process.

As with other medicines, vaccines may have side effects on some individuals. These would be written on a small leaflet included within the vaccine's packaging. However I have searched three journal databases (namely ScienceDirect, PubMed, and EBSCO) and found no scientific literature linking vaccination to autism.

Instead, I have found papers with evidence against this claim for the MMR vaccine. Perhaps there is something I missed that the readers would like to point out.

The issue of vaccination is a complicated one. One which involves the safety of the public (whether from the disease or the vaccine itself), and the freedom of the individual. I feel it is not my place to debate and articulate this thorny issue, but I feel compelled to point out that the benefits of vaccination extend beyond the individual vaccinated.

It is something called ‘herd immunity'. Put simply, it simply means that even those who are not vaccinated, or already vaccinated but still vulnerable for some reason (for example, weakened by other illness, the vaccine did not take full effect, ect.) are still better off if their community is already vaccinated simply because the disease has a harder time spreading. This is certainly a food for thought in the ethical debate of vaccination.

As for Wong Ang Peng's ‘Latest flu outbreak an American plot', it must have been the most outrageous and scientifically inaccurate article I have read for some time. Diseases have a long history of cross-species transmission (zoonosis), both human to animal and vice versa.

This dates back to the time when humans first domesticated animals and come in close contact with them. Perhaps longer. Recall the famous story of Edward Jenner, who was inspired to invent a vaccine for the deadly smallpox after he discovered that milkmaids who had cowpox are immune to smallpox?

Where had she contracted cowpox from? From cows of course, but this was in the late 18th century, well before we are aware of the existence of genes, never mind manipulation. Indeed, even the dreaded smallpox had bovine origins.

Also noteworthy in this story, is that the viruses involved used double-stranded DNA as their genetic material. This is highly stable and less susceptible to random mutation, in contrast to the influenza virus' highly mutable RNA. Nonetheless, it has somehow made the jump from cow to human.

Today, because of its inability to mutate and change rapidly, it has been eradicated by a massive vaccination campaign by the WHO and all its horrors are now a thing of the past.

Wong is also incorrect that organisms are incapable of sharing genetic material between species. Need I remind you how mules are born? At the micro level, this happens routinely in nature, with bacteria sharing genetic information with other bacteria, and even with plants. Viruses, especially influenza viruses, have their own way of mixing their genes without human intervention.

Horizontal gene exchange between bacteria and viruses occur too. Flu vaccine manufactures constantly monitor the genetic makeup of flu viruses in order to keep up. Indeed, it can take months (but not years) to develop a new flu vaccine.

What the CDC has done is merely making the virus' genome more readily available to researchers, it is still very far from a working vaccine. The latest quote I had is from Protein Sciences, which claims that it will have a vaccine ready for testing in six weeks. See here .

On his advice on vitamin C, I am not sure how useful this is for swine flu, but it reminds me of a particular former South African health minister who denied the existence of Aids (which affects a quarter of its population) and prescribed beetroot juice instead of anti-retroviral drugs for its alleged sufferers. This, of course, cost lives. Nonetheless, a good, balanced diet is always sound advice, with or without an impending pandemic.

As for his conspiracy theories, I have no wish to argue. These have been raised, debunked, raised, debunked, rinsed and repeat, over and over again. Tantalising, but no thanks. Nature is an amazing thing, full of surprises but not always to our advantage.

While human achievements are no small thing, nature sometimes gets too little credit. But sometimes, nature gets too much credit, considering all the hype on natural medicine without much study. If only we could learn more of what has nature done, and what have we done, hand-in-hand.

Dear Dr Wong and ‘Progress at Any Cost', while I don't doubt that your intentions are good, please check your facts. Lives are at stake here.