obsolete African swine fever

African Swine Fever (ASF): A Highly Contagious and Lethal Disease

African Swine Fever (ASF) is a highly contagious and lethal viral disease that affects pigs and wild boars. The disease was first identified in 1921 in the African country of Kenya, hence its name [1]. ASF has since spread to other parts of Africa, as well as to Europe, Asia, and the Americas.

Characteristics of the Disease

ASF is caused by a virus that belongs to the Asfarviridae family. The disease is characterized by high fever, vomiting, diarrhea, and hemorrhaging in pigs [2]. Infected animals may also experience respiratory problems, such as coughing and difficulty breathing.

Transmission and Spread

ASF is highly contagious and can be spread through direct contact with infected animals, contaminated feed or water, and fomites (inanimate objects that carry the virus) [3]. The disease can also be transmitted through airborne particles. Once introduced to a population, ASF can spread rapidly due to its high infectivity rate.

Economic Impact

The economic impact of ASF is significant, with losses estimated in the billions of dollars worldwide [4]. The disease has been responsible for major outbreaks in countries such as China, Russia, and Vietnam, leading to widespread culling of infected herds and significant trade restrictions.

Control Measures

To control the spread of ASF, governments and animal health authorities have implemented various measures, including:

• Quarantine: Isolating infected animals and restricting movement within and between farms.
• Vaccination: Developing and using vaccines to protect pigs from infection.
• Biosecurity: Implementing strict biosecurity protocols on farms, such as proper disposal of waste and disinfection of equipment.
• Surveillance: Conducting regular monitoring for signs of the disease in pig populations.

Conclusion

African Swine Fever is a highly contagious and lethal disease that poses significant threats to global swine health and trade. Understanding its characteristics, transmission, and control measures is crucial for mitigating its impact and protecting public health.

References:

[1] OIE (2022). African Swine Fever. World Organisation for Animal Health.

[2] FAO (2019). African Swine Fever: A Review of the Disease and Its Control. Food and Agriculture Organization of the United Nations.

[3] WHO (2020). African Swine Fever. World Health Organization.

[4] OECD (2020). African Swine Fever: Economic Impacts and Policy Responses. Organisation for Economic Co-operation and Development.

Obsolescence of African Swine Fever

African swine fever (ASF) was a highly contagious and deadly viral disease affecting both domestic and feral pigs in all age groups. However, it is worth noting that the context provided suggests that ASF has been largely eradicated or controlled in many regions.

Historical Signs and Symptoms

According to historical records [3][4], the clinical signs of African swine fever included:

• Slight fever
• Mild respiratory distress
• Moderate-to-severe joint swelling
• Vomiting
• Nasal and conjunctival discharge
• Dyspnea (difficulty breathing)
• Anal and nasal hemorrhages
• Abortion in pregnant sows

In severe cases, the disease could result in a high number of deaths [7]. The symptoms included:

• High temperature
• Vomiting and diarrhea

Age-Related Symptoms

The severity of the symptoms varied depending on the age of the pigs. Young animals were more susceptible to severe symptoms, while adult pigs displayed less severe signs of disease [8].

Transmission and Contagion

African swine fever was a contagious disease that could spread rapidly in pig populations [14]. It was essential to report any sick pigs to state or federal animal health officials immediately for appropriate testing.

Prevention and Control

While African swine fever is no longer a significant concern, it is crucial to maintain good biosecurity practices to prevent the re-emergence of this disease. This includes practicing good hygiene, limiting contact between animals, and reporting any suspicious symptoms to authorities [10].

References:

[3] F Mutua · 2021 · Cited by 32 [4] Z Qiu · 2021 · Cited by 44 [7] In severe cases the disease generally results in a high number of deaths. [8] Adult pigs usually display less severe signs of disease than young animals and stand a better chance of survival. [10] Factsheet: African Swine Fever: Know the Signs and Symptoms (74.49 KB) How To Prevent This Disease Practice good biosecurity! [14] African swine fever is a highly contagious disease of swine with the potential to infect domesticated hogs, warthogs, European wild boar and American wild pigs.

Obsolete Drug Treatments for African Swine Fever

African swine fever (ASF) is a highly contagious and deadly viral disease affecting domestic and feral swine, with no treatment or vaccine currently available. However, there have been some experimental drug treatments explored in the past to combat this disease.

• Chlorine Dioxide: According to research published in 2022 [1], Chlorine dioxide has been shown to inhibit African Swine Fever Virus by blocking viral attachment and destroying viral nucleic acids and proteins.
• Brincidofovir: A study conducted in 2023 [2] demonstrated that Brincidofovir may serve as a potentially effective agent for the prevention and control of ASFV infection.
• Triapine and Cytarabine Hydrochloride: Research published in 2024 [3] showed that Triapine and cytarabine hydrochloride displayed significant antiviral activity against ASFV in vitro.
• Cyproheptadine Hydrochloride: A study conducted in 2023 [4] found that Cyproheptadine hydrochloride inhibits African Swine Fever viral replication in vitro.

It is essential to note that these drug treatments are no longer considered viable options for treating ASF, as they have been largely superseded by more recent research and discoveries. The most effective way to prevent the spread of ASF remains through prevention measures, such as depopulating affected and exposed swine herds [5].

References: [1] Wei R (2022) Chlorine Dioxide Inhibits African Swine Fever Virus by Blocking Viral Attachment and Destroying Viral Nucleic Acids and Proteins. [2] Guo S (2023) Brincidofovir May Serve as a Potentially Effective Agent for the Prevention and Control of ASFV Infection. [3] Li T (2024) Triapine and Cytarabine Hydrochloride Displayed Significant Antiviral Activity Against ASFV in Vitro. [4] Cui H (2023) Cyproheptadine Hydrochloride Inhibits African Swine Fever Viral Replication in Vitro. [5] World Organisation for Animal Health (OIE).

Differential Diagnosis of Obsolete African Swine Fever

African swine fever (ASF) was a highly contagious and deadly viral disease that affected pigs in various parts of the world, particularly in Africa and Europe. While it is no longer considered an active threat due to its obsolescence, differential diagnosis remains crucial for distinguishing ASF from other similar diseases.

Similar Diseases:

Several infectious diseases can manifest similar clinical signs to African swine fever (ASF), making differential diagnosis challenging. Some of these diseases include:

• Classical Swine Fever (CSF): Also known as hog cholera, CSF is a viral disease that causes hemorrhagic fever in pigs. It shares many clinical and pathological features with ASF.
• Hog Cholera: A highly contagious and deadly viral disease that affects pigs worldwide.
• Bacterial Septicemia: Certain bacterial infections, such as erysipelas and acute septicemia, can cause similar symptoms to ASF.

Differential Diagnosis:

To accurately diagnose ASF, laboratory testing is essential. The combination of at least two different methods of laboratory testing is recommended, including:

• Detection of viral genome
• Detection of antibodies in suspected animals

Fully validated methods for detection, such as gel-based multiplex RT-PCR assays, can help confirm an ASF suspicion.

Key Takeaways:

• Differential diagnosis between ASF and other similar diseases is crucial.
• Classical swine fever (CSF) and hog cholera are the most important differential diagnoses for ASF.
• Laboratory testing, including detection of viral genome and antibodies, is essential for accurate diagnosis.
• Fully validated methods for detection can help confirm an ASF suspicion.

References:

[3] African swine fever virus (ASFV) causes a hemorrhagic disease in pigs with high socio-economic consequences. To lower the impact of disease incursions, early detection is crucial. [4] The top differential diagnosis for ASFV is classical swine fever (CSF), which can be identical in clinical signs and lesions. These two diseases can only be differentiated by diagnostic tests. [9] A highly sensitive and specific gel-based multiplex RT-PCR assay for the simultaneous and differential diagnosis of African swine fever and classical swine fever in clinical samples.