African Swine Fever and Avian Influenza : the next viral threats?

The COVID-19 pandemic and its health and economic consequences have dominated the news worldwide in the last few months. However, COVID-19 is not the only disease that is currently on the rise and that could have an impact on the global economy.  Since 2019, more and more pigs and boars have contracted African Swine Fever (ASF). Similarly, Avian Influenza has re-emerged and is infected larger numbers ofbirds. These two diseases could have important economic consequences on the pig and poultry markets, but also more broadly on the animal protein market! Our team takes stock of these upcoming viral threats.

African Swine Fever (ASF), a contagious disease that endangers the world’s pig population

African Swine Fever, or ASF, is a viral disease that affects domestic pigs and wild boar but is not transmittable to humans. The main symptoms of this disease are high fever, loss of appetite, and reddening of the skin, especially in the ears. The most virulent strains of the virus cause death within 2 to 10 days with a mortality rate approaching 100%. Less severe strains of the virus also exist with 30 to 70% mortality rates.

ASF is highly contagious. Several modes of transmission exist:

– Via contact between mucous membranes or scratches, or indirectly via animal secretions (excrement, urine, semen, blood)
– By ingestion of food contaminated by the virus (hardly cooked or uncooked meat)
– From by contaminated materials (syringes, boots, clothes, vehicles, etc…) that have come into contact with infected pigs
– By ticks

The virus is very resistant to cold and freezing temperatures, but also to heat (up to 56°C!) which explains its presence in undercooked food such as meat. It is sensitive to some detergents, including ether, chloroform or sodium hydroxide, but once a place is contaminated by the virus, it is difficult to get rid of it. To date, there is no approved vaccine against African Swine Fever, but the American Society of Microbiology announced in early 2020 in the Journal of Virology that a vaccine in development appears to be working, though testing is still not yet complete and the vaccine has yet to be marketed. In March, a publication from the China Veterinary Research Institute also indicated that an effective vaccine had been developed, but clinical trials have not yet been initiated.

The disease was first described in Africa. While a few ASF outbreaks were noted in Europe and America in the 1990s, the virus reappeared in Georgia in 2007 in the form of a massive outbreak before spreading to Russian-Caucasian regions. In 2014, the first cases were discovered in Poland, and then China in 2018. Today, the disease is spreading at a rate of about 350 km per year, making it a global threat.

The current situation in China is complicated: it is estimated that the disease decimated 40% of the Chinese pig population in 2019. At the beginning of 2020, the virus is still far from being eradicated.

Resurgence of avian influenza threatening the world’s wild and domestic bird populations

Along with ASF, the Avian Influenza is making a comeback. This virus affects both wild and domestic birds. It exists in a large number of forms, some more dangerous than others for infected individuals. The viral infection can be asymptomatic or lead to non-specific symptoms such as behavioral disorders (undernourishment, sensitivity to the cold…) and respiratory disorders. Some strains of the virus can infect humans, such as the H1N1 strain that caused the global pandemic from 2009 to 2010.

In early 2020, the H5N1 strain was detected in the Hunan province in China, in a farm of 7,850 hens, 4,500 of which died from the virus. To prevent the spread of the virus, 18,000 poultry were slaughtered following the discovery of this outbreak.

In Asia, as of February 2020, 37 outbreaks were still being reported. Numerous outbreaks are currently occurring in Europe and the virus, that was initially detected in Poland, is moving westwards. In early February 2020, the H5N8 strain was detected in a backyard in south-western Germany, 100 km away from the French borders. Mortality among those birds was as high as 80%.

Although the origin of the different strains of the virus, the contagiousness rate and the risks for humans are not yet well understood, veterinary authorities have asked affected countries to redouble controls to avoid the need to slaughter animals.

Two viruses with significant economic consequences

The mass slaughter of infected or suspected virus-carrying animals has global economic consequences. China, which is the world’s largest consumer of pork, has increased its meat imports by 63% in 2019 (see Figure 2) to compensate for the decline in production due to ASF. This production drop has an impact on the flow of pork, but also poultry and beef worldwide.

The increase in meat demand in China is a direct consequence of the general increase in prices. As a matter of fact, meat prices increased by an average of 40% in China in 2019, 23% in France, 37% in Germany and 31% on average in the EU between January 1 and June 3, 2019.

Meat-producing countries (Brazil, Eastern European countries) are now having difficulties meeting this demand. This is why the ASF being on the doorstep of Germany, Europe’s largest pork producer, is worrying the market.

Moreover, if the spread of avian flu leads to mass slaughter of poultry, the prices of animal proteins will continue to soar, which will then pose the problem of access to these proteins, especially in countries where populations already cannot always afford the recommended daily intake. Other indirect repercussions are to be expected on the price of vegetable proteins, but also on the market for substitutes to animal products and on the evolution of dietary habits.

About the authors

Amélie, Consultant in Alcimed’s Life Sciences team in France
Alice, Project Manager in Alcimed’s Life Sciences team in France