A new influenza pandemic is quite possible, according to a study by researchers at the University of NSW’s School of Public Health. The study notes that 19 different influenza strains have affected humans in the last 100 years, but the speed with which new strains have emerged has increased over the past 15 years. There have been seven new strains in the past five years alone.
Professor Raina MacIntyre, director of the UNSW Integrated Systems for Epidemic Response, said while factors such as climate change and increased urbanisation impact on pathogens, the rate of change far outstrips the changes taking place in such factors. She emphasised the need for much better collaboration between countries as well as sectors such as agriculture, health, emergency services and defence to improve the response to such an event.
Recent strains seem to be mainly transmissible from birds or swine to humans and not between humans, but the large number of viruses today raises the likelihood of mutation to a between-human spread — a pandemic. Such a speed-up affects the production of appropriate vaccines.
The baseline for the danger and lack of preparedness for human influenza is the 1918–19 pandemic, which infected about 500 million people and killed an estimated 50 to 100 million people worldwide.
This pandemic occurred in three waves. The first was in March 1918, when the mortality rate was more like previous influenza outbreaks. But the second outbreak in September and the third outbreak in early 1919 were highly fatal with death rates 5 to 20 times higher than expected.
Viral analysis took place much later from samples of second wave frozen corpses. These showed a migration across species, probably initially from birds to swine and humans and then human to human transmission.
In Big Farms Make Big Flu, published last year by Monthly Review Press, Rob Wallace agreed a pandemic is not just more than likely, it is probable, and echoes the necessity to prepare. But his focus is to identify why the rate of new virus strains has increased, which he sees as basic to how to effectively plan containment.
Wallace is an evolutionary ecologist who has expanded into phylogeography by examining the economic geography of the location of an influenza outbreak and the ways that shifts in agriculture impact on the evolution of pathogens. He has worked with the United Nations Food and Agriculture Organisation and Centres for Disease Control and Prevention.
The book looks at a broad range of infectious agents such as viruses, bacteria, fungi (pathogens) and their associated diseases, but focuses primarily on influenza.
Basis of pathogen strain increase
Wallace argues that the speed up in new pathogen strains is linked inextricably to the changes in food production since World War II.
Global agribusiness meat production today is based on the Taylorist time-and-motion factory model where maximum profitability shapes productivity. This starts with shaping the type of animal best suited for quick development and fast delivery to market at the lowest cost, in a business strategy based on maintaining a steady flow of product.
This model was first pioneered in the US in the 1940s for poultry but has spread worldwide. It was taken up by the pig industry in a major way in the 1990s.
For example, the industrial stockbreeding for chickens selects the breed for quick development and hybridises it for business outcomes for broilers as well as hens. Broilers raised for meat production reach slaughter weight at 5 to 6 weeks, whereas other breeds take about 14 weeks. They grow three times faster on less than half the feed, which is in part due to selecting against the pituitary regulated cap on appetite. This means the bird develops big breasts but suffers from skeletal damage to its legs.
Hens or layers are selected to raise egg production from 250 eggs a year up to one a day. In Israel in 2009 researchers selected a line of featherless birds, cutting out one stage in the production line and speeding up the preparation for market.
Today, nearly three-quarters of the world’s poultry production has consolidated into a few multinationals. Those who control the primary broiler breeders’ market declined from 11 companies in 1989 to four in 2006. The 10 companies producing layer lines consolidated from 10 to two in the same period.
Multiplier companies are offered only males of the male line and females of the female line. The resulting batches of hybrid chickens based on trade secrets mirrors Monsanto seeds.
They must be purchased continually. Yet the danger of the narrowness of the base of genetic stock raises the potential destroy-or-damage susceptibility of a monoculture to new diseases.
Agribusiness production is structured vertically at a national level. The company owns and controls every stage of the process: it provides the poultry, feed mix and schedule delivery; medicine to avert disease and gain weight; sets prices for chickens based on weight; and slaughters, processes and markets the meat.
They spread this on a global scale, setting up such vertical structures across countries for poultry and feed production, often retailing their product through a variety of fast-food chains. Such a global spread means that when an avian flu outbreak occurs in one country the company can substitute supply from another location.
These arrangements produce big market benefits through economies of scale that squeeze smaller local companies and local farmers out of the market, reducing competition. Establishing such a spread politically and financially influences government decision-making to their benefit.
They can avoid national government health oversight, regulations and penalties by setting up in countries with little regulation, low production costs or corruption of officials. Structural adjustment regulations cutting public health infrastructure and undermining national legislation for loans from the International Monetary Fund and the World Bank impose privatisation programs by default. Free trade agreements open opportunities for dumping of product, overriding industrial law and undermining trade unions.
Vertical integration and total company control are basic to the industry. But the risk factors of disease and stress of huge monocultures of, for example, 50,000 turkeys or 250,000 chickens per barn, lead to a severe diseconomy of scale.
So the cost and risk of raising the birds is shifted onto contract farmers who, as employees, must take bank loans to afford the land, barns, equipment, and bills for electricity, heating, fuel and water for the birds. While their debt is measured in decades, the company contracts run a matter of weeks and are reissued flock by flock.
If there is an outbreak of bird flu, that too is externalised onto the contractor with no insurance for the loss of the birds as well as the costs of government regulation. Their barns are out of commission for the 28 days of composting to which the dead birds must be subjected before being sold as crop fertiliser. They must then lie vacant for an additional 21 days before they can be repopulated.
No wonder smallholding farmers, like their counterparts in India subjected to the cost shifting and dangers from the Green Revolution, are killing themselves at a high rate.
There is a further externalised cost to the taxpayer as the government is responsible for regulation and oversight of the culling of poultry.
Disease consequences of flu
Southern China has become a global centre for production based on this model. It began with the opening up of Special Economic Zones in the late 1970s, mainly for foreign joint venture cheap labour manufacturing.
But in the 1990s this changed to include poultry production, especially of chickens, ducks and geese. Faecal waste from the birds, all-year rather than seasonal flu period and intense human population growth close by, all raise the risk of a human-specific viral strain developing.
In Hong Kong in 1997, a deadly bird flu swept through poultry on two farms, then stopped. Two months later a child died of the same highly pathogenic strain, which apparently jumped the species barrier. This was followed later by a small number of infections and deaths linked to handling of poultry.
By the end of the year birds began to die in the city’s markets. The authorities stepped in, ordering the destruction of all 1.5 million poultry in the city.
Infected birds die from the inside out, imploding from internal organ damage. Humans similarly suffer organ breakdown and collapse, especially the lungs, often leading to patients effectively drowning in their own fluid within days of infection.
In Mexico in 2009, an outbreak of a new strain of swine flu spread globally through human to human contact to many countries quite quickly. This was put down to airline travel from the initial outbreak near Mexico City and its international airport facilities to New York and San Diego. It was highly contagious and spread out through each centre or country as it arrived.
The World Health Organisation (WHO) reported 15,510 official cases in 53 countries. As flu can transmit before symptoms appear, this had all the indications of a pandemic, but while this flu spread quickly its virulence presented as no more than a bad seasonal flu.
It showed this strain can cross host species of swine–bird–human and across the countries of North America and Europe, not just the countries of the Global South or China.
In March 2015 a different avian strain led to an epidemic in turkey and chicken farms in the US and spread rapidly. Nine million birds were killed across 108 farms in 23 counties at a huge loss of profit in an industry worth $265.6 billion annually.
Blame was attributed to wild birds, smallholders, farm workers, the weather, the wind, flies and rodents — in short, everything except the agribusiness industrial model.
Virulence is defined in terms of the magnitude of damage a pathogen causes in the host. Key concepts include: transmission where the virus kills too quickly before infecting the next host; immunity in the host; co-infection by related or unrelated competing strains in the host; and the supply of susceptible hosts.
Basic to the evolution of pathogen virulence is the supply of susceptible hosts to infect. Once that supply no longer exists, either through high death rates or the build-up of immunity, that particular strain burns out. All influenza epidemics cease eventually, but that is not reassuring if millions of people die in a pandemic.
The WHO has operated the Global Influenza Surveillance Network for the past 65 years. Countries forward samples of prevalent influenza strains, which it offers at no cost to pharmaceutical companies willing to make vaccines.
These companies sell the vaccines to countries that can afford them — populations in highly industrialised countries. Populations in poorer Third World countries are excluded by cost, so they refuse to send on such samples. This means that scientists are excluded from the process of identifying the evolutionary ecological and sociological basis of the emergence of new strains.
Other forms of censorship of necessary information go much further. In the US, farmers traditionally have pigs tested for flu at diagnostic labs of the National Animal Health Laboratory Network. These laboratories, often housed in universities, work for the farmers, who they see as their clients, and thus keep the outcomes confidential.
They work on the belief that the pig samples are owned by the farmers so the information is theirs alone, not the government’s. So this data is not shared with virologists, epidemiologists and phylogeographers who are the best informed to protect both livestock and humans.
Wallace made the point that “a federal government of a major industrial country won’t provide the information needed to determine which farm or even in which county an outbreak has occurred”. Only the state in which the outbreak occurred is made available by law.
So economics trumps population health. The US government, which could force this information into a federally-run and industry-subsidised surveillance system does not do so due to the political power and influence of big business. Wallace also noted somewhat wryly that China has less censorship than the US on such outbreaks.
Wallace’s argument is compelling. His book outlines a broad range of viral species shifts to human outbreaks based on crop and meat agribusiness production, while arguing for the alternative of sustainable agriculture.
It is certainly worth the read and it definitely encourages you get your annual flu vaccine shot.