African swine fever

African Swine Fever

African swine fever (ASF) is a highly contagious viral disease that affects domestic and wild pigs. It is caused by the African swine fever virus (ASFV), which is a large, double-stranded DNA virus belonging to the family Asfarviridae. ASF is characterized by high mortality rates and can have devastating impacts on pig populations and the pork industry.

History

The disease was first described in the 1920s in Kenya, and it has since spread to many parts of the world. ASF has been endemic in sub-Saharan Africa, but outbreaks have occurred in Europe, Asia, and the Americas.

Transmission

ASF is primarily spread through direct contact with infected animals or their secretions, such as blood, saliva, and feces. It can also be transmitted via contaminated feed, equipment, and clothing. Soft ticks of the genus Ornithodoros can act as vectors, transmitting the virus between pigs.

Clinical Signs

The clinical signs of ASF can vary depending on the virulence of the virus strain and the susceptibility of the pig population. Common symptoms include:

• High fever
• Loss of appetite
• Weakness
• Reddening of the skin, particularly around the ears and snout
• Diarrhea
• Vomiting
• Respiratory distress

In severe cases, ASF can lead to death within 6-13 days after infection.

Diagnosis

Diagnosis of ASF is based on clinical signs, laboratory testing, and polymerase chain reaction (PCR) assays. Serological tests can also be used to detect antibodies against ASFV.

Control and Prevention

There is currently no vaccine or treatment for ASF. Control measures focus on preventing the introduction and spread of the virus. These include:

• Strict biosecurity measures
• Quarantine and culling of infected animals
• Proper disposal of carcasses
• Disinfection of contaminated areas

Economic Impact

ASF can have significant economic impacts due to the loss of pigs, trade restrictions, and the cost of control measures. The disease poses a major threat to food security and livelihoods, particularly in regions where pig farming is a key agricultural activity.

Research

Ongoing research efforts are focused on understanding the virus's biology, developing effective vaccines, and improving diagnostic methods. Collaborative efforts between governments, international organizations, and the scientific community are crucial in combating ASF.

See Also

• Swine influenza
• Classical swine fever
• Porcine reproductive and respiratory syndrome

References

• Dixon, L. K., et al. "African swine fever virus." Annual Review of Virology 6 (2019): 197-214.
• Penrith, M. L., et al. "African swine fever." Transboundary and Emerging Diseases 66.2 (2019): 689-701.

External Links

• World Organisation for Animal Health - African Swine Fever
• Food and Agriculture Organization of the United Nations - African Swine Fever