African swine fever: a transboundary virus that defies biosecurity mechanisms

Entry of African swine fever (ASF) in July 2021 on the island of Hispaniola (Dominican Republic – Haiti) it forces other countries in the region to “drop their chins in the water” and Panama does not run away from this reality.

The presence of ASK in the region tests the ability of countries to establish their own biosecurity strategies, as well as strategic risk communication, which is crucial for protection against the virus, which, due to its high mortality and resistance, has already been cataloged by experts as the ‘Virus Terminator’.

African swine fever (ASF) is a deadly disease that affects pigs and is caused by a virus that is highly resistant to the environment, Despite the fact that it is not a zoonosis, that is, it does not infect humans, it is very destructive to the production and economy of the country, explains Víctor Neira, an expert on pig health from the University of Chile.

ASK affects pigs at any stage of their life, as well as feral pigs (feral pigs), and is transmitted by a soft tick that is present throughout the world. It is probably one of the most resistant viruses in nature, it is difficult to control and it is a transboundary disease, which indicates that the virus can travel long distances, explains a researcher from the Veterinary School of the University of Chile.

Due to the biological impact that ASK has on the production chain, Neira qualifies the ASK virus as a ‘Virus terminator’. This virus can cause high mortality, 100% in a pig farm, which in intensive production can be from 40,000 to 100,000 heads or two animals in a backyard farm.

When the virus reaches an intensive farm in the country, it gets out of control because there are a lot of animals there, which causes an extreme viral load, which will be transferred between farms in one way or another, he explains. There are multiple possible modes of transmission or spread within the country, including through the air, so preventing the entry of African swine fever (ASF) is the only key to protecting the production chain and economies of countries in the region. region, explains an expert from the University of Chile.

The air itself inside the farm can be a means of transmission, but by transporting pigs in the yard or family production, the virus can reach a distance of up to 1000 kilometers.. Those 1,000 kilometers can be compared to the distance between Santiago de Chile and Buenos Aires in Argentina, Lima and La Paz, Mexico and Guatemala, as well as between Guatemala and Panama, an expert from the University of Chile explains in detail.

The ASK virus has 175 known genes, which makes it impossible to make an effective vaccine. Complete depopulation of pigs or euthanasia remains the only effective way to eradicate the virus, which represents a high economic cost for both producers and the country’s economy. The former also includes a 50% increase to double the cost of pork.

Epidemics that occurred in China a few years ago, where large numbers of animals were slaughtered for eradication programs, caused a steady increase in pork prices, including in Latin American countries, such as Chile, where export production is preferred.

Globally, pork is one of the most consumed, so if this disease spreads around the world, it will cause damage to various economies, explains Neira. If a country has ASK, there will be pig mortality, this does not mean that production will disappear, but food would be produced with the virus present, which, although it does not affect humans, has as a trigger the further spread of the disease.

resistant virus

Any food of pig origin can contain the virus, especially that which has not undergone the cooking process, which facilitates the transport of the active virus between countries, explains Neira. With one gram of positive sausage, you can infect practically all the pigs in Chile, six million animals, Neira points out about the impact that a contaminated product would have entering the country through any port.

The risk is also represented by the informal and illegal importation of pig products into the country, the virus can also be present in products that travelers bring in, which can later be consumed by animals in the form of garbage, explains Nicolás Winter, in charge of the FAO’s African swine fever project (ASF) for Latin America and the Caribbean.

The virus present in a product stored at 4 degrees Celsius can resist up to four months or a year, in frozen meat for 2 years, in frozen blood for more than 6 years, in pig feces for about 160 days, in bone marrow for several months and years. It is also resistant to PH from 4 to 11 degrees. It can also remain viable on contaminated objects such as rubber, glass, metal and paper.

Biosecurity is a set of activities whose purpose is to control the main sources and ways of spreading of pathogenic biological agents, and what it is intended to do is to prevent the entry, contain and avoid the internal spread of these pathogens, FAO experts explain.

Countries in the region such as Panama have requested assistance from FAO to implement disease warnings in the region, the need to adopt a preventive approach and strengthen biosecurity. Panama maintains an active individual strategy, but also in coordination with the countries of the region, explains Nicolás Winter, responsible for the African swine fever (ASF) project of the FAO for Latin America and the Caribbean.

Pork production in Latin America is estimated at 8.1 million tons of meat, and in the United States at about 12 million tons. In Panama, pig production is the fourth most important agricultural activity, representing 7.7% of the gross value of agricultural production, about 158.2 million dollars per year. 539,610 pigs are slaughtered annually, or about 45,000 pigs per month.

For the winter, the strategy must focus on prevention by strengthening borders both for risky goods and for tourists entering the country who may transmit the virus without realizing it.