Thursday, November 03, 2005

Birdfluenza!

To be very honest, I started to write this piece with intentions of heaping adulation on a vegetarian diet, since I was of the opinion that the new disease in town, the Bird Flu was going to affect only poultry eaters. Although there has been a lot of news coverage on this recently both in the international media and the Indian press, I had ignored it as something not very relevant to a hardcore vegan. What caught my attention to it was a news piece about the settlement in the Lipitor battle between Pfizer and Ranbaxy. The article about the high profile global lawsuit about interpretation of patent laws also carried an interesting side note about the dire consequences of a draconian patent regime in case of a bird flu pandemic where the pharmaceutical company licensed to produce a anti viral drug used for treatment, could not match up to the global demand.

This obviously caught my attention and I did a little research about this new disease on the internet and found that there definitely is a cause for concern in case of world wide out break of Bird Flu. Not going into very detailed description of the genetics of the issue, which I certainly am not qualified to explain, here is a gist of the biology behind this disease, which I have been able to understand. Bird flu or H5N1 as it is called in scientific terminology is one amongst the many strains of influenza virus found in migratory birds. These birds carry these and many other strains of the virus in there intestines and they have no harmful effect on the birds which do not fall sick or die as a result of such infections. The different strains of the virus have varied reactions on different species of animals and H5N1 seems to have a fatal effect on poultry birds like ducks, turkeys and particularly chicken, and when these migratory birds come in contact with these poultry birds the virus jumps from one species to another and here begin all the problems. The disease spreads when the infected bird’s saliva or feces comes in contact with other animals. I am not sure of the symptoms of the disease in these birds which may involve cough and fever, but the crux of the issue is the highly contagious nature, among these birds of the H5N1 virus.

Before going any further, for those interested in the terminology of H5N1 let us examine in slightly more detail what this stands for. As we all know there are vaccines available for influenza and treatment for cases of flu is common in human medicine. But why then do people need to take flu shots ever so frequently and why do doctors prescribe different medicines at different times? This is because the influenza virus can mutate and these leads to different strains of the virus and the same vaccination can not work for all strains. Also, some of these mutations develop into drug resistant strains and hence there is a need for constant upheaval of the drugs which can counter these new strains. Now, a virus is a genetic material encapsulated in a protective coating material. When this entity attaches itself to the cells of the host that’s when a virus “attack” takes place. The surface of the virus has spike like extensions which are mainly protein components, and these receptor binding proteins, as they are called are responsible for the process of attaching the virus to the host cell. The influenza virus has around 500 such spikes and they are made up of two types of viral proteins called Hemagglutinin (HA) and Neuraminidase (NA). Different combinations of these proteins are denoted with different HN terminology like H5N1, H3N2 etc. If the host cell tissue, the upper respiratory tract in case of influenza virus, is not conducive for a particular combination of the viral proteins then the virus cannot attach itself and hence is harmless to the particular species having that tissue.

This strain is still a predominant threat only among poultry birds and there still is very little evidence of it making successful jump to humans. What is worrying the medical fraternity is that among the 100 or so reported cases of humans being infected with H5N1, there has been a 60% mortality rate. The first case of a human being infected with this strain was reported in 1997 in Hong Kong and since then there have been around 100 odd cases reported, around 60 of them since 2003. Although these statistics may not be very indicative of a major epidemic, the worry is about the hitherto un-reported cases of this virus. The people directly in contact with infected birds like the poor poultry farmers in South East Asia are the people mainly affected by the disease. It has been spotted extensively in countries like Vietnam, Cambodia, Indonesia and China. The concern in the international community seems to be about countries like China not disclosing the extent of the cases of bird flu, as a safeguard against trade restrictions on poultry products. Another cause for concern is the impending mutation of the virus which may make it easier for the disease to be transmitted to humans from these poultry.

Research has intensified for developing the drug and vaccines for this strain and although a vaccine is not available as yet, Glaxo SmithKline has indicated that they are on the verge of developing a H5N1 vaccine. Currently the disease is being treated using two drugs, Tamiflu, available in capsule form from the Swiss drug maker Roche and Relenza, available as in to be inhaled, powder form GSK. Going by the estimates of past flu pandemics, where the people affected world wide being around 50 million, and at a rate of 40 tablets per person, it is not difficult to fathom the large market for drugs like Tamiflu should the disease breakout among humans. It is also believed that the extent of pandemic may be worse than before affecting well over a 100 million people world wide. All these indications and the pressure from governments has made drug companies including Roche, who own rights to Tamiflu to declare that in the event of a global pandemic outbreak, they would be willing to share the rights to manufacture of these drugs to other companies. Such schemes of patent sharing does not always lead to the desired social good which they start out to achieve, as drug quality is the first to be hit in such cases where there is a substantial demand for a new drug to be manufactured by those companies who have not done so before. Nevertheless, it is imperative that a better solution to deal with the capacity shortages in companies like Roche be addressed at the earliest. In such situations, it might be worthwhile to track the stocks of these companies in the near future!

There has been precious little said or done about this situation in India. I for one have not seen in the press much talk about preemptive action to counter a threat of H5N1. Although the bird flu as of now seems to be still confined in the South East Asian countries, the poor hygienic conditions of the poultry markets in India and the seasonal interaction of poultry with the migratory birds are all very conducive for a widespread outbreak. In spite of the belief in the medical circles that consumption of poultry products may not lead to spread of the disease, more than 100 million poor chickens have slaughtered as preemptive action in South East Asian countries. It is yet to be seen if such barbaric yet required preemptive action is being considered in India. The congested and populated environment in India may actually prove to be a deadly breeding ground in case of a mass outbreak.

There may not be a case for an alarmist reaction to the situation but the general consensus amongst the medical fraternity is that caution has to be exercised. Indications are that there might be an effective vaccine ready by the time the virus mutates into a form which can affect humans more easily. With reports of the flu spotted in places like Turkey, Kazakhstan, Romania and few other parts of Europe, there is indication that the flu is spreading along with the migratory patterns of birds. As it is not possible to exterminate these infected species of birds as can be done with infected domesticated chicken, containment of the spread may not be possible. Effective quarantine measures are being initiated in these countries and around Europe and America. This vaguely reminds of the book Kalki by Gore Vidal, where a meglomaniac in the effort to start a new superior race of humans, hires a pilot to fly all around the world dropping leaflets loaded with a deadly poison which kills anyone who comes in contact with it. But one can be sure that there will be no one demented whacko behind a flu pandemic, but a whole bunch of unhygienic communities!

According to my understanding, it is the quarantine method that needs to be adopted in India. With the extremely deplorable conditions of the poultry breeding infrastructure in the country, the chances of the presence of bird flu is very likely. The best solution would be to study and quarantine the infected lots at the earliest. Also hygiene awareness should be improved and the deplorable conditions in which poultry and livestock are reared should be changed for the better. Of course being a vegetarian reduces a person’s direct contact with poultry products, it is nevertheless worthwhile to maintain strict levels of cleanliness in the fruits and vegetables we eat. As being a vegetarian does not also reduce one’s chances of being “bombed” by a bird, it may not be sensible, in the future to treat it as a lucky charm as some people do so today!

References:

  1. Website of the Centre for Disease Control and Prevention (CDC): http://www.cdc.gov/flu/avian/
  2. Science Explained: http://www.synapses.co.uk/science/fluvirus.html
  3. CNN’s report “Bird Flu: Preventing a Pandemic”

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