Bird flu pandemic: West Bengal chickens out

If you think that the H5N1 avian flu virus, which hit West Bengal on 16 January 2008 and caused poultry losses of Rs. 350 crore, has been entirely and irrevocably contained, think again. Scientists see increasing indications that the 15 types of avian flu viruses circulating around the world are mutating so swiftly that a strain capable of jumping the human-to-human barrier is inevitable in the short term.

Despite the undeniable presence of this spectre, the West Bengal government declared precipitously on 14 July that it had decided not to allow vaccination of birds ‘as its efficacy is yet to be proved’. Avian vaccination is considered by experts worldwide to be the only prophylaxis against a future outbreak, but Animal Resources Minister Anisur Rahaman insisted that traces of the vaccine that were found in the blood of the vaccinated birds could—potentially—affect poultry consumers.

He didn’t, however, back up his claim with empirical evidence. Since 1997, when the H5N1 virus was first identified in Hong Kong, there has been no scientific or statistical proof that the H5N1 vaccines for birds pose any danger to humans. If the minister’s statement of concern for the electorate was a cover for economic expediency, it’s a very skimpy one. Avian flu vaccines for birds—as opposed to those for humans—won’t bankrupt the state government. The cost of each vaccine—which can be used on birds both before and after an outbreak—created as long ago as July 2006 by the Bhopal-based High Security Animal Disease Laboratory (HSADL), worked out to 35 paise, including traders’ profit and cost of transportation.

Also, a state government official recently confessed that those involved with the fowl culling operations in West Bengal were ‘seriously worried’ because ‘the H5N1 virus is still in circulation in the state’ and that ‘(o)ver four districts have already reported reinfection’, and that ‘(r)epopulation and infiltration have already started in several districts’. Avian influenza control and containment protocol says that an infected area should not be permitted repopulation of poultry for at least three months from the date that culling teams wind up disinfection operations.

The next flu pandemic, which will most likely be based on one of H5N1’s mutations, could take out between two million and 50 million people worldwide, triggering entire societal die-outs and a global economic cave-in of unprecedented proportions.

In fact, the human-to-human mutant of the virus might already be out there: there have been three suspected cases of human-to-human infection, one each in Thailand (2004), Hong Kong (1997) and Indonesia (June 2006). It would be unrealistically optimistic to believe that the H5N1 can be easily contained. Professor Dr. Prasert Auewarakul of Mahidol University, Thailand, said on 8 July ‘that the H5N1 virus is adapting each time it infects a human. Such adaptations may lead to the emergence of a virus that can cause a pandemic’.

Immediately following the 2008 bird flu outbreak in West Bengal, WHO declared that the next pandemic would probably be centred in Southeast Asia, with the epicentre being the Indian east—and it hasn’t redacted that prognosis. In April this year, the UN had issued its bluntest warning to India since the first avian flu outbreak in 2006. Dr David Nabarro, the UN’s influenza coordinator, said that the virus had, in all probability, become entrenched in the Indo-Gangetic plains of India and Bangladesh.

‘We have got bird flu now in Southeast Asia, Central Asia, Eastern Europe, and West Africa’, Nabarro said on 20 July. ‘Compared with eight months ago, this is a major extension of the avian influenza epidemic’.

In fact, contrary to the Food and Agriculture Organisation’s statement that ‘(n)o new disease outbreaks have been discovered since 2 February 2008’, an outbreak occurred in Darjeeling as recently as on 10 May, long after the ban on the sale and consumption of poultry products and meat in the state was lifted in late February.

The reasons why the epidemic took such fierce hold in West Bengal still exist—the highest population density of all states in India, delayed action, bad planning and mismanagement by the state government, porous segregation zones, inefficient biosecurity measures, and people resisting culling operations, led by CPI (M) leaders worried about cascading insolvency caused by the government’s inability to deliver compensation money adequately and on time.

What Anisur Rahaman should really be worrying about is H5N1 vaccines losing their potency over time. In July this year, the head of the microbiology department at the University of Hong Kong revealed that a poultry vaccine designed to protect chickens in Hong Kong from the H5 strain had lost efficacy over the past seven years of use because of tangential virus mutation. Tests on birds in 2005 suggested that the antibody response to the vaccine was only 25 per cent of that in 2001. The microbiologist told Hong Kong city officials that it was imperative that all live chickens be banned from markets before vaccine-immune birds begin being transacted.

West Bengal’s Achilles’ heel lies in the CPI (M)’s irradicable populism. In April, with elections just a month away, politicians were reported intervening in the culling and containment efforts, alleging that the methodology was menacing. On 12 April, in fact, a team from the Central government’s Department of Animal Husbandry lodged a complaint upon its return from West Bengal that culling operations were being hampered by the ungoverned run-up to the elections.

The World Health Organisation’s (WHO) case fatality ratio (CFR) reports on avian flu read alarmingly. The mortality rate in 2007 (59 out of 88 cases) was 67 per cent. In 2008, it has risen to 76 per cent (26 out of 34 cases). As of 19 June 2008, the total avian flu CFR over the years was 63 per cent (243 deaths from 385 cases).

In a lab test that sought to mimic a possible real-life scenario, scientists recently reported a successful fusion—known as ‘reassortment’—of H5N1 with a strain of the human flu virus named H3N2, producing a hybrid virus. H3N2 is one of the two influenza viruses that commonly affect humans during flu seasons.

While many nations have developed pandemic plans and are stockpiling antiviral drugs such as Roche’s Tamiflu and GlaxoSmithKline’s Relenza, India is not one of them. The UK government, for instance, has reserved the right to buy up to 122 million doses of pandemic flu vaccines from a variety of suppliers in case of an outbreak. In contrast, during the January 2008 outbreak in West Bengal—the 10th avian flu malignancy in the country since its emergence here in February 2006—the state government received only 36,000 doses of the Tamiflu oral antiviral treatment, all of which were given to hazmat-clothed cullers and none at all to the unprotected poultry farmers, many of who were dirt-poor.

An official at the National Institute of Communicable Diseases (NICD) said that the ‘avian flu story’ was far from over. He referred to the unequivocal cautions handed out by Dr. Malik Peiris, the Sri Lanka born, Hong Kong-based virologist who discovered the aetiological agent that causes Severe Acute Respiratory Syndrome (SARS) and who is at the vanguard of research into the H5N1 virus. ‘If you look back at all the major emerging infection problems over the last few decades—whether West Nile or mad cow disease or the avian flu or SARS—these were all animal pathogens that jumped to humans’, Peiris said.

Warning that the avian flu virus problem had been ‘grossly underestimated’, Peiris said that in regions where the virus was endemic, the magnitude of poultry infected with the virus was far higher than people imagined. Poultry sold after entering a market might not seem to be dying of the virus. But this ‘sleeping’ virus continues to circulate on the busy back-and-forth transaction route between farm and market, finding purchase wherever it can. ‘Once the virus gets in a market’, Peiris said, ‘it remains there almost forever’. And no market is as chaotic, unhygienic and unmonitored as an Indian one.

Furthermore, the political and social fractiousness between India’s eastern states could hardly help contain the spread of avian flu. For instance, the Orissa Veterinary Association (OVA) decided in February not to participate in any systematic ‘ring vaccination’ (vaccinating all birds in a 5-10 km radius of the outbreak) along the Orissa-West Bengal border, on the grounds that since no infections had been detected in Orissa, the killing of healthy poultry would contravene the basic principles of veterinary ethics. The OVA chose to be blind to the possibility of infection infiltration from West Bengal into Orissa.

WHO had said that the poultry farms—backyard flocks, live bird markets and commercial farms—of India, Bangladesh, Myanmar, Indonesia and Thailand were likely to be both the most vulnerable to and the most rabid vectors of the avian flu virus. It doesn’t help West Bengal’s case that 29 of the 64 districts in Bangladesh, which has a notoriously lax biomonitoring and medical system and which shares a long border with West Bengal, were affected. Officials said that vector tracking showed that a significant part of the avian flu crossed over—probably through smuggled poultry—into West Bengal, which declared itself hit on 15 January, from Bangladesh, which had announced its outbreak earlier on 3 January.

Then, again, the whole issue of the H5N1 virus is perforated with the ideological ironies that always attend an overlapping of geopolitics and national administration. When, in end-January this year, the Union Ministry of External Affairs accepted US ambassador David C. Mulford’s offer of American assistance in tackling the bird flu outbreak, the West Bengal government knew full well that it would be the first beneficiary.

The irony here is that not only would Left-run West Bengal benefit from an extreme capitalist government that it detests but also that the global community of virologists is aware that several US laboratories are creating and experimenting with novel influenza types that could, if they escaped, start a formidable bushfire. In one well-known example, US scientists recently rejuvenated the extinct 1918-19 Spanish flu that had killed 50 million people, claiming against all logic that the anabiosis would help the world prepare for an H5N1 pandemic.

The H5N1 virus prospers amidst this welter of political and scientific paradoxes.