By Shipra Prakash
24 June 2008 [MEDIAGLOBAL]: Even as Dr. David Nabarro, the United Nations System Influenza Coordinator, was speaking to a group of correspondents at the UN Secretariat about the improvements and remaining challenges in combating avian influenza, the Indonesian Health Ministry reported the deaths of two women from bird flu. Indonesia has had more human bird flu infections than any other country, with 110 deaths out of 135 cases.
Nabarro said that many countries had improved the functioning of veterinary services and bio-security in the rearing of poultry.
He commended the United Kingdom and the Republic of Korea for their quick and successful responses to bird flu outbreaks. But other countries have not been able to achieve similar results.
Nabarro pointed out that in 2008 there have been outbreaks among poultry in Indonesia, Vietnam, Bangladesh, Egypt and to a degree, Nigeria, although the situation in Nigeria had improved in recent months.
The Food and Agriculture Organization (FAO) reported in March that Indonesia is the country hardest hit by avian influenza.
With 20 percent of the country’s 1.4 billion chickens raised in backyards—the place where some 30 million Indonesian households raise poultry for food or income—special attention to the disease is warranted.
“Indonesia is facing the highest number of H5N1 cases in poultry,” Erwin Northoff, a spokesperson for the FAO, told MediaGlobal. H5N1 is the name of the virus that causes avian influenza.
But humans are being affected as well, according to Joseph Domenech, FAO Chief Veterinary Officer.
“The human mortality rate from bird flu in Indonesia is the highest in the world and there will be more human cases if we do not focus more on containing the disease at source in animals,” he said.
“The major challenge is to immediately apply the main components of a successful national avian influenza control strategy, based on effective surveillance, emergency culling and compensation, vaccination, improved biosecurity, effective laboratory and quarantine procedures, and movement controls of poultry and poultry products,” Domenech added.
According to Nabarro, much past human suffering can be attributed to the animal kingdom. Yellow fever originated in monkeys; HIV/AIDS began in a simian species and the respiratory disease SARS was believed to have come from bats, he said.
Armed with this knowledge, health officials in recent months have been drawing on the bird flu experience to analyze other diseases that could affect humankind. With the ‘One World, One Health’ initiative, UN agencies have been acting to bring veterinary professionals, human health experts and ministries of agriculture together with livestock departments.
Such projects are aided by the fact that funds received by the UN are not earmarked for any particular sector. National governments have pledged $2.7 billion in the past three or four years for the purpose of fighting outbreaks, and these funds can be used for both humans and animals, Nabarro said. On the human side, the funds have been used to build up the capacities of health systems to ensure better surveillance and faster, more comprehensive responses.
On the subject of treating infected humans, there is the question of whether a one-drug strategy will be effective.
A study published in the journal Nature in May revealed that no single drug would be sufficient to handle a global flu pandemic because the H5N1 virus is shown to be developing resistance to the leading anti-viral drug, Tamiflu.
The flu neuraminidase (N1) releases the virus from infected human cells, spreading the disease. Tamiflu and another drug, Relenza, restrain neuraminidase and so restrict the movement of the virus.
When a team at the National Institute for Medical Research (NIMC) — which is largely supported by the Medical Research Council (MRC) —used X-ray crystallography, a mutation in N1 was found, which has also been found in human incidences of H5N1.
The team discovered that when this mutation occurred the virus became resistant to Tamiflu, although it was still affected by Relenza.
“It is evident that a single drug has severe limitations,” Dr. Alan Hays, Director of the World Influenza Centre at NIMC and one of the authors of the study, told MediaGlobal.
The leading author of the study, Dr. Steve Gamblin, said “in order not to be outflanked by the virus, it will be necessary to have stockpiles of both drugs.”
“There is a huge imperative to develop further drugs and it is likely a future pandemic will need to be tackled using a three or four-pronged approach, much as we tackle HIV today,” he added.
Dr. Rupert Russell, a Lecturer at the UK-based University of St. Andrews’ School of Biology and another author of the study, agreed with Gamblin on the issue of stocking both drugs.
“I feel there is a need to stockpile both Tamiflu and Relenza, as there are growing concerns of Tamiflu-resistant viruses,” he told MediaGlobal.
Stocking both drugs could prevent large numbers of deaths. As the saying goes, it is better to be safe than sorry.