Avian Flu
UN warns governments to remain vigilant

In an interview with IRIN, Dr David Nabarro, the United Nations’ senior coordinator for avian and human influenza, says although global defences against avian influenza have been strengthened, there are still challenges ahead in limiting the damage should the virus mutate into a form easily transmissible between humans.

Dr David Nabarro, the United Nations’ senior coordinator for avian and human influenza, said governments around the world must be poised to aggressively contain any localised outbreak of H5N1 influenza in humans and to limit the fallout. He added that in the event of a human influenza pandemic it will be vital to keep essential services running.

Dr Nabarro made the comments while in Bangkok in late November to plan the next stage of Asia’s battle against bird flu. He said Asian governments faced a long battle to control the virus in their vast bird populations, and to transform the poultry industry to reduce the likelihood of farmers contracting the lethal H5N1 avian virus from ailing birds.

“It doesn’t require a lot of thinking to understand what the magnitude of the impact of a pandemic will be,” he warned. “We are not talking about a health crisis, but a social, economic and governance crisis.”

Many public health specialists believe the world is overdue for another influenza pandemic, which in the 20th century typically occurred every 27 years. The worst pandemic was in 1918, when flu infected a quarter of the world’s population – and claimed 40 million lives. Since the last flu pandemic was in 1968, analysts say the chances of a new pandemic are rising. The H5N1 virus – which causes highly pathogenic avian influenza – has proven particularly virulent in the relatively few humans it has infected, killing 152 of the 256 people known to have been infected.

But so far, the virus has not proven easy to transmit between people, partly because the virus lodges in the lower part of the infected person’s lungs. However, public health analysts’ great fear is that the virus will mutate into a form that lodges in the upper part of the human respiratory system – as human influenza typically does – which would make it far easier to transmit from person to person, potentially triggering a new human flu pandemic.

“We are expecting an influenza pandemic any time,” Dr Nabarro said. “We just don’t know when, we don’t know where it is going to start, and we don’t know how severe it is going to be. If it is this H5N1 virus that mutates and becomes the cause of the next pandemic, and if that virus maintains the kind of virulence that it has shown in birds, it will be a horrible pandemic.” While virologists differ on the likelihood that H5N1 will mutate into such a form, the potential consequences could be devastating – both in terms of lives lost and the massive disruption to travel, business, government and all aspects of everyday life.

The comparison with Sudden Acute Respiratory Syndrome (SARS), which struck several Asian countries in 2003, is instructive. Although the SARS outbreak was classed as a “public health success”, which claimed less than 1,000 lives before the virus was eradicated, the episode – and the panic and fear associated with it – resulted in economic damage of about US$50 billion, mainly to Asian economies.

The World Bank and International Monetary Fund have estimated that the cost of a virulent influenza pandemic could be far worse – into the trillions of dollars. But the UN is collaborating with governments to try to prevent socio-economic meltdown should a pandemic occur. “There are ways in which we can prepare for economic continuity, continuity of governance, of security systems, of humanitarian relief on a massive scale,” he said.

“It requires planning, identifying essential functions, and development of standard operating procedures for how we will work with 30% absenteeism. And it requires exercises, simulations, and drills to test how we are getting on.”

Such work “parallels the thinking they have to do for major security outrages. It’s not an unreasonable thing to be doing,” Dr Nabarro said.

Yet global efforts to prevent, or limit, such a catastrophe will require huge resources – both financial and technical. Dr Nabarro estimates the battle against bird flu will require between $500 million and $1 billion of new funding each year over the next decade to help countries, particularly poor countries that are most likely to be first affected, to bolster their bird flu defences.  

As one urgent measure, Dr Nabarro said many countries still had to strengthen their public health systems, particularly their surveillance capacities, to be able to quickly detect and contain an outbreak of avian influenza in humans and to prevent the virus from spreading widely throughout the population.

“Human health systems, if they do pick up a cluster of severe human flu-like illness, need to have the capacity to contain this virus and stop it from spreading,” he said.

“Containment means initiating actions where people’s movement is limited, where people are encouraged to not mix with each other in crowded places, and when sick to stay home and isolated as much as possible.”

When the H5N1 virus began to kill vast numbers of birds in southeast Asia in late 2004, regional governments were slow to recognise and respond to the threat, with some authorities even attempting to cover up the extent of poultry deaths. The denials and delays proved costly, allowing the virus to spread and take root, while also killing dozens of people in the region.

Subsequently, Asian governments embarked on aggressive campaigns to contain the virus, culling millions of birds. Yet the H5N1 virus is still circulating in parts of Indonesia, and also thought to be endemic in Vietnam, Thailand and China. The fact that some birds, including ducks and wildfowl, can carry the virus without falling ill or displaying symptoms has hampered efforts to stamp out the virus completely.  

In 2006, the virus surfaced in many other parts of the world – including eastern Europe and Turkey; the Middle East and sub-Saharan Africa – having been carried by migratory birds and introduced into domestic poultry populations.

But authorities moved swiftly, helping to bring the virus under control, though it appears to be still circulating in certain parts of Egypt and Nigeria. Dr Nabarro also said governments and local communities could ill afford to be complacent since the virus could reappear at any time.

Specifically, governments and communities must be prepared when there is a new outbreak to rapidly restrict movements around affected farms, cull birds on affected farms and surrounding areas, and keep the area clear of poultry for a long time before restocking.

“Most countries in eastern Europe would be able to control any new outbreak now much more rapidly than they did at the beginning of 2006,” he said.

“In sub-Saharan Africa and the Middle East, “all these countries have got a much better functioning system than before, and that is a very good sign”.

Asian countries have also made “huge progress” in responding to outbreaks in birds and strengthening their animal-health systems. But developing countries, especially in Asia, face a long-term challenge of overhauling their poultry industries – partially by reducing the movement of live birds – to increase biosecurity, and reduce the risks of people contracting the virus from ailing birds.

“We’ve got a 10-year challenge ahead of us,” Dr Nabarro. “What was initially treated by some as an emergency is now turning into a long-term programme in which we are trying to upgrade animal health, with veterinary services, greater bio-security for poultry rearing, and more attention to the quality of slaughterhouses and markets.

“In Indonesia particularly, but also China and other parts of this region, we’ve just got to transform the way poultry are reared,” Dr Nabarro said.

“It will be a long haul and we are going to have to maintain focus on it.”

Such dramatic changes would also require “mass social mobilisation” through  large-scale public-awareness campaigns targeting rural communities in Asia – an effort that has begun with money from Japan and the US, though Dr Nabarro said such initiatives still needed to be expanded.

“We need to move people from ‘shock-horror-fear’ to having a pretty clear idea of what actions they will need to take, their families will need to take, and their communities will need to take to limit the threat,” he said.

Public health professionals are trying to work out how to simplify the messages on bird flu to effectively communicate the most important points to the public, such as washing hands and keeping distance from animals.

“We’ve started to see the kind of investment in public information that is necessary, but it is still only scratching the surface,” he said.

“It’s tricky – we have to change public attitudes internationally because of a problem that still is not tangible to very many villagers.

“To encourage them to change the way they care for their poultry, or to pay more attention to contagion and hygiene, on the basis of a risk that is intangible to them is never easy.”

It’s not just villagers who feel little sense of urgency: Dr Nabarro said he is frequently asked whether the seemingly abstract threat of avian influenza is more hype than reality.

“People ask me all the time, ‘is this H5N1 really going to change its genetic make-up and become capable of human-tohuman transmission or is it just going to coexist alongside the human race and then fade out in due course?’ My answer is, I do not know.”

Yet even if avian influenza ultimately recedes as a threat and the worst fears about a devastating human illness are never realised, Dr Nabarro said the global efforts to beat the virus are valuable preparation for governments, and rural communities, to cope with other disease threats that may begin in animals and migrate to humans.

“Seventy per cent of the pathogens that are going to affect the human race in the future will come from animals,” he said.

“To have human health services, and animal health services, that are working together is extremely reassuring.

“To have a human health service that is capable of detecting strange new bugs that may come from animals is an extremely good thing for the future of human kind.”

                                               Copyright © 2007 MiddleEastHealthMag.com. All Rights Reserved.