Are we capable of coping with the deadly bird flu?

Andrio Adiwibowo, Jakarta

In the aftermath of the polio outbreak, we are faced with grave doubts about our capacity to cope with the current outbreak of avian influenza. The disease has claimed more lives in a shorter period. Within three months, four deaths have been confirmed and the number of patient is still increasing. That the outbreak is centered in the capital city of Indonesia has shocked officials.

Moreover, many researchers are extremely surprised about the emergence of avian influenza in humans in Indonesia. They had believed that avian influenza was restricted to animals and there was only a very small possibility that it could infect humans. However, the facts have proved otherwise.

Avian influenza is not a new disease, especially in the Asian region. There was an outbreak in 2000, even though it was insignificant. At that time, a small number of chickens in isolated poultry farms in Vietnam were killed by H5N1, an agent of avian influenza. International researchers had warned most countries in this region, including Indonesia of the possibility of the virus spreading.

Based on good evidence, the next great pandemic is not a matter of if, but when and where. From 2000 to 2004, avian influenza cases occurred sporadically, not frequently. The rarity of this event has tempted us to underestimate the threat. During that period, it seems that the virus has become stronger and more virulent. Today the death toll is evidence of that.

Today, a wild bird population has been accused as the reservoir of the virus. This may or may not be true. The existence of viral diseases is common in nature. Nature has its own mechanism to activate and turn off the disease. The purpose of this mechanism is to maintain equilibrium. In the wild, approximately 20 percent of a bird's population may carry a disease.

However, these numbers are not a threat to the human population at all. They only live in remote places that are far from urban centers. The problem emerges when irresponsible act alters the system. Many people in developing countries are involved in hunting and trading wild birds. People snare the wild birds and trade them, or in other words they have introduced the birds along with their diseases to the human community.

Therefore, the rule of thumb is one sick bird that is kept as a pet is more likely to infect human beings than tons of sick birds that lived in their own habitat. Jakarta itself has some large bird markets, and hundreds of wild bird-trading centers, both legal and illegal. We can only imagine how many diseased birds are circulating and the threats we are facing now.

Avian influenza is endemic and probably ineradicable among poultry in Southeast Asia, and now seems to be spreading at a pandemic velocity. Correspondingly, unhygienic poultry practices in most developing countries also support the spread of the disease. Current evidence suggest that intensive farming practices, inadequate disease control, trade in live poultry, mixing of avian species on farms and at live bird markets, and poor bio-security in poultry production contribute much more to the spread of the disease than wild bird movements.

Overcrowding of birds within intensive farming practices that causes close contact with fecal and other secretions has resulted in the transmission of the virus at a greater rate. Likewise, lack of control on transported poultry products, including infected poultry, along with high mobilization across the city has also widened the transmission from farm to farm.

The current belief that avian flu occurs exclusively where there is close contact between humans and poultry may prevent us from encouraging greater awareness and attention to this disease. It is naive to believe that human to human transmission could only happen by chance and the probability is insignificant. It is true that there is no evidence of human to human transmission to date.

However, in the future, a strain might acquire the ability to "jump species", either by mutation or by recombination of genetic material with a human influenza virus and the ensuing virus would then be highly pathogenic and transmissible causing an influenza pandemic.

The up side of the story is that avian influenza is by no means new and a cure is already available. Most developed countries are already prepared, yet the effectiveness of the vaccine is still in question.

First, there is no guarantee that the vaccine prototype, based on a reverse-genetically-engineered strain of H5N1, will actually be effective against a pandemic strain with different genes and proteins. The epidemiological observations and sequencing analyses of genes from avian and human H5N1 viruses "demonstrate that the viruses are continuing to evolve and pose a continuing and potentially growing pandemic threat.

Next, gearing up for larger-scale production will take many months and production itself is limited by the antiquated technology of vaccine manufacture, which depends upon a vulnerable and limited supply of fertile chicken eggs. It would also likely mean the shortening of the production of the annual winter flu vaccine that is so often a lifesaver for many senior citizens. Moreover, there is not enough vaccine or antiviral medicine available to protect more than a handful of people, and no industrial capacity to produce a lot more of these medicines quickly.

At the least, developing poor country will suffer a lot more than the developed world. The majority of the world, including all the poor countries of South Asia and Africa where, history tells us, pandemics are likely to hit especially hard, will have no access to expensive antivirals or scarce vaccine. It is even doubtful whether the minimal medicine to respond to an initial outbreak are available adequately.

Correspondingly, immediate steps should be taken to improve monitoring and assessing the risk for pandemic influenza in all countries where avian H5N1 viruses are present. Measures to reduce the threat of pandemic influenza including developing an international stockpile of antiviral drugs and making a vaccine available in affected countries in Asia should be mandatory.

The writer is a researcher in the Public Health and Virology Department at the University of Indonesia, Jakarta. He can be reached at andrio7897@yahoo.com.