Thursday, July 16, 2009

Swine Flu: Reason To Panic?

A pandemic means an epidemic that spreads in different parts of the globe. The World Health Organisation (WHO) has raised the worldwide pandemic alert level to Phase 6 in response to the ongoing global spread of the novel influenza A (H1N1) virus. Raising of the alert level to Phase 6 – the highest level of alert – have further fuelled fears of an impending global health emergency.

More than 70 countries, including India, are now reporting cases of human infection with novel H1N1 flu. This number has been increasing over the past few weeks, but many of the earlier cases reportedly had links to travel or were localised outbreaks without community spread.

The WHO designation of a pandemic alert Phase 6 reflects the fact that there are now ongoing community level outbreaks in multiple parts of world. There have been widespread speculation in the lay press regarding the possible consequences of the pandemic.

According to the WHO, we clearly, have a full-scale pandemic on our hands and the stage of containment is fast running out. The US recently admitted that there are already an estimated 1,00,000 cases of the infection in the country.

Margaret Chan, Director General of the World Health Organisation, recently warned in an interview that it is not possible anymore to contain and reverse the spread of the pandemic. While the epidemic unfolds, certain issues regarding the genesis of the pandemic and the global response, merit a closer look.

Pandemic Preparedness In An Unequal World
First, let us examine the global response to the pandemic. One lesson stands out loud and clear. The present methods of containing a pandemic are ineffective and perhaps useless.

This is linked to the fact that surveillance systems for monitoring the spread of infections are deeply embedded in the public health systems. In many parts of the world, public health systems are in a state of disarray and ill equipped to mount any meaningful surveillance.

After the Avian Flu scare in the late 1990s the WHO has tried to promote a strategy of identification and isolation of a pandemic strain within its local radius of outbreak. This strategy has clearly floundered in the face of the present epidemic. We can see clearly that public systems in many parts are incapable of monitoring outbreaks that can spread fast (like the present one).

Moreover, there doesn’t exist any effective mechanisms to monitor and contain the spread of epidemics from the reservoirs of such epidemics created by agribusiness. To do so would require enormous political will by countries such as the US, as one would need to confront the economic and political clout enjoyed by giant agribusiness corporations.

As health authorities move on to the next step towards addressing the public health effects of the epidemic, the focus shifts towards drugs and vaccines. Predictably, the inequity prevalent in the globe is starting to be played out again in the globe.

On one hand, the Swiss multinational Roche, is trying its best to make a killing from the patent that it holds over Tamiflu – the only known medicine that can ameliorate the symptoms of the disease (though it cannot cure or prevent it entirely). Interestingly, Tamiflu is not even an original Roche innovation – the patent was bought over by Roche from a smaller company.

Indian generic companies like Cipla are in a position to produce Oseltamivir, its generic version of Tamiflu, but Roche will now try to prevent these from being sold in markets where Roche holds a patent. Fortunately, there is no Tamiflu patent in India, thanks to the now abrogated Indian Patent Act of 1970. But it has already granted a local company Hetero Drugs. Hetero is the only local company that has a sub-licence from Roche to manufacture Tamiflu, which it does on the payment of a royalty to Roche.

The same North-South divide is being played out in the case of vaccine development as well. It is widely anticipated that an effective vaccine will be available by the coming winter. It is also clear that vaccine manufacturers will not be able to produce enough vaccines to supply to all populations in the globe.

The WHO estimates drug companies will be able to produce between one billion and two billion doses of vaccine a year for a pandemic - far short of the world's population of 6.8 billion also given that two doses of the vaccine are likely to be required for every person. So we already have unsavoury deals being struck by rich countries in the US and Europe to corner a major portion of the vaccines that will be produced.

The US, for example, has awarded Novartis AG $486 million toward the construction of a vaccine factory that will be able to produce 150 million doses of the vaccine within six months of a pandemic being declared - a deal that would give priority to US needs when the vaccine is developed. Similarly, the UK, similarly, has struck a four-year, £155.4 million contract with Glaxo Smith Kline and Baxter International Inc that guarantees delivery of up to 132 million doses of vaccine.

Further, since some time, there has been a global consensus on the need to have transparent methods by which countries share information about viruses that they collect from different regions in order to do research on the pathogens and also to produce vaccines (under the rubric of what are called: “Virus Sharing Agreements” or “Material Transfer Agreements”.)

In the past few months the US and other developed countries have obstructed discussions on such an agreement as they want to be in a position of advantage as and when remedies are developed for the present pandemic.

No Clarity
Indeed, though designated as “Swine Flu” by the global media, there is still no clarity regarding the origin of the new influenza virus. In fact, the Paris-based World Organisation for Animal Health (OIE) has expended considerable energy trying to keep people from calling the virus Swine Flu.

The OIE's quite legitimate concern is that this nomenclature might adversely affect trade, with countries taking unnecessary measures such as culling herds, or invoking trade bans on pigs and pork.

What we do know is that the present flu virus will not spread through consumption of pork. But the genetic evidence does point to the possibility that the present strain is a reassorted swine influenza virus, which has acquired genetic material from strains affecting birds and humans, and has jumped from pigs to humans.

The “Swine Flu” scare has a long history. In 1998 an extremely virulent variant of the virus was reported, which killed thousands of pigs on a farm in North Carolina in the US. Ever since, new strains appeared every season, and some of these strains showed up genes from the influenza Type-A virus seen in humans.

Six years ago, the prominent journal 'Science' had reported that the North American Swine Flu virus was on “an evolutionary fast track”. The journal detailed how, after decades of “stability” the virus had started mutating.

While it is virtually impossible to accurately predict when a virus will “jump species”, i.e. change from one capable of only infecting animals to one that can infect and spread among humans, we do know that the swine population is a reservoir of viruses that can mutate and afflict humans. Two of the great influenza pandemics in recent history – in 1957 and in 1968 – are believed to have originated from the mixing of bird and human viruses inside pigs.

Viruses have been known to jump species for long. What is however of interest and concern is the fact that there appears to be an acceleration of the process in recent times. The Swine Flu epidemic comes close on the heels of the avian flu scare a few years back. Not just influenza viruses – new virulent strains of viruses capable of causing other disease in humans have been emerging with disconcerting regularity in the past decades.

Agribusiness’ Microbe Factories
To understand why this is happening, we need to understand what factors influence the emergence of new strains of viruses. Random mutations take place constantly in nature. However almost all such mutations do not result in a new variant that is able to sustain itself in a population of animals (or humans).

Environments where viruses have access to large animal populations living in close proximity are known to be the best breeding grounds for new strains of viruses. Such environments provide viruses with the two basic ingredients required to thrive and spread – a large number of hosts in which to grow and multiply, and other hosts to which they can migrate.

It is from such a pool of genetic mixing that a virus capable of causing pandemics emerges. While known strains of influenza affect millions of humans every year, they do not cause serious symptoms in most and do not spread very fast.

This is because after a virus has established itself in a human population over a period of time, most people develop some levels of immunity to the virus. As a consequence most people do not get the disease even when infected, or only develop mild symptoms.

The people who get very sick are usually those who are already vulnerable – children, old people, those with other underlying diseases, etc. On the other hand when a new virus starts spreading, the entire population has little or no immunity. So the disease spreads rapidly and causes more severe symptoms.

In the past such conditions existed within the environment of intensive agriculture in South China, where cultivation of rice, and rearing of pigs, poultry and fish take place in close proximity. The major pandemics of the 20th century were thus believed to have originated from this environment.

However, today, we have a more potent sources of new viruses – what can almost be termed as virus producing factories. Livestock rearing has undergone major changes in the past few decades with the advent of corporate-owned industrialised modes of livestock rearing.

The giant livestock farms – that are the hallmark of industrialised livestock production – have thus become the breeding grounds for new viruses. Statistics from the US show livestock rearing has been transformed. In 1965 there were 53 million pigs on more than a million farms, while today 65 million pigs are concentrated in just 65,000 facilities. Half of these house more than 5000 pigs each (Mike Davis: 'Global Agribusiness, SARS and Swine Flu' in The Asia-Pacific Journal, Vol. 18-1-09, May 1, 2009.).

It is not just the large number of animals being in close proximity that promotes breeding of pathogens. These animals are housed in cramped quarters, have little scope for exercise, live in suffocating heat and surrounded by their excreta, have little contact with the outside environment and made to breed among themselves.

They are, thus, animals with weak immune systems that are perfect for the introduction of any new pathogen. Such farms are breeding grounds for exotic species of drug resistant bacterial and protozoal pathogens as well, fuelled by the widespread and indiscriminate use of antibiotics in the captive animals.

Clearly there is a need for much larger scrutiny of the conditions in which animals are reared in corporate run farms. At present, for example, there is no requirement that the authorities be notified of flu in pigs, as the animals generally recover, and farmers have little incentive to report an outbreak in their herds given the potential repercussions.

More advanced forms of co-operation are required to examine the interface between human and animal health. Corporations need to be reined in so that their hunger for super profits do not come at the expense of human health at a global level.

Meeting The Challenge
While the present pandemic is a real public health emergency, it is also necessary not to fall prey to scaremongering. What we know about the present epidemic indicates that at present the virus, though highly infective, does not generally cause very severe symptoms – it has been labelled as “moderate” in its ability to cause morbidity or mortality in humans.

Also, to put the numbers of deaths and infected patients being reported at present in perspective, it should be understood that 36,000 people die in the US every year due to influenza related complications caused by existing influenza viruses.

What is unusual about the present pandemic is that it seems to affect young and middle aged adults more than children and the old. It is also likely, as in all past influenza epidemics, that the temperate regions of the world (North America and Europe) will be affected to a much larger degree than tropical and sub-tropical countries such as India. This is due to geophysical and climatic characteristics of temperate regions in Europe and North America, which help the transmission of the virus.

The pandemic will intensify in all likelihood in the coming winter, especially in Europe and North America and could be expected to start declining in a year or two as larger populations get exposed and develop some immunity. Then we shall wait the advent of the next pandemic!

We cannot predict that it will not be more virulent than the present one unless we wake up to the need for better surveillance, better public health systems, better sharing of research in the world and more sustainable ways of rearing livestock.

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