Diseases A-Z

What is Swine Erysipelas?

Swine Erysipelas is a severely contagious disease that results from an infection caused by the Erysipelothrix rhusiopathiae bacterium. As much as 50% of the pig population carries this virus, and it is therefore impossible to completely eliminate it from a herd. The disease is commonly found in the tonsillar tissue of the swine.

It is crucial to understand that erysipelas is zoonotic – meaning that it can be passed from an animal to a human.

Erysipelas is also a common cause at abattoirs when it comes to carcass condemnation.  You can also read more about the African Swine Fever on our blog.

Common Causes

• Damp, and dirty pens with a build-up of feces that is not maintained regularly.
• Feeding systems that are wet, are excellent breeding grounds for germs.
• Pens that are not regulated with an all-in, all-out system, to allow for adequate disinfection.
• Contaminated water systems and feed-backs.
• Sudden temperature changes in the environment – especially warmer conditions
• Changes in the diet that are done too quickly and not facilitated at a gradual pace.
• Parasitic burdens.
• Investing in animals that have not been vaccinated, puts the whole herd at risk.

Methods of Transmission of Swine Erysipelas

The disease is transmitted via the secretion of feces, urine, or oronasally (saliva) from one pig to the next. It can even penetrate the skin from lesions

Other species from the animal kingdom such as birds and other mammals, can also play a part in the transmission of this disease via contaminated soil and slurry.

Even though a pig can be a carrier of the disease, it is quite possible that this carrier won’t even show any clinical signs or symptoms thereof.

The disease can be transmitted via other means as well such as contaminated meat, carcasses, bones, and fish.

Detection and Clinical Signs of Swine Erysipelas

It is found that the swine erysipelas disease can either be chronic or acute in nature. Chronic outbreaks can embody characteristics such as; enlarged joints and lameness. And acute outbreaks (that normally sprout from chronic outbreaks) can take on forms such as sudden deaths, febrile episodes, lack of appetite, sore joints, and a variety of lesions on the skin. 

Both the chronic and acute occurrences can have a recurring or a once-off appearance. Stressful conditions such as extreme heat, whilst being transported can also play a part in the development of the disease. Pigs won’t be able to stand up without assistance and might want to lie back down again. Thirst and starvation (by the pigs themselves) have been observed in previous cases, with the affected swines seeking cool and wet conditions to try and eliminate the ill-feeling being experienced.

Pigs that have been infected will die suddenly, become dull, and will have a fever between 106 ℉ – 109℉. Accompanying all of these occurrences will be a crimson flush on the pig’s skin. Infected swines will also display reluctance to move.

The onset of diamond-shaped lesions on the skin, especially behind the ears, will start to manifest within 48 hours after the infection has occurred. Pregnant sows might abort their piglets.

There is a good chance of an infected animal recovering completely, however, the prevalence of necrotic tissue, loss of the tips of the ears, and sore, hot, and painful joints should not be disregarded. Lameness might occur, but the limbs will firm up again within 2 weeks. Even after a full recovery heart murmurs and congestive heart failure should not be ruled out as a primary cause of death.

Other clinical manifestations include:

• Arthritis 
• Cutaneous Erythema
• Endocarditis
• Septicemia

Available Treatment Options

Long-acting Penicillin injections have shown to be an effective treatment that yields rapid results, in terms of the recovery process. 

Any pens, dens, and other bedding and living spaces should be disinfected and properly cleaned with immediate effect.

Preventative Measures against Swine Erysipelas

Routine and scheduled vaccines against the E rhusiopathiae have proven to aid in the prevention of the illness. The conditions and times of vaccination are unique to every farm and should be carefully monitored and planned around suspected outbreaks before they occur.

The possibility of adequate and regular vaccines have been known to fail, due to the lack of adequate stress management on swine farms. Stress can severely compromise the overall health of pigs.

Lastly, frequent sanitation exercises and good hygiene practices are also great methods in curbing the swine erysipelas virus.

Key Takeaways

• Enforce a regular round of preventative vaccines to combat the disease.
• Do not purchase pigs that have not been vaccinated, or this can compromise the health of the entire herd.
• Ensure pens and houses are disinfected on a regular basis.

What is Classical Swine Fever? (CSF)

This is an easily transmitted disease that has a high fatality rate amongst hogs or pigs. CSFV causes infected swine to develop a fever, excessive bleeding, lethargy, diarrhea that is yellow in color, retching, and purplish-colored skin discoloration of areas such as the ears, legs, and lower stomach.

Transmission and Spread

In most cases, the CSF virus is transmitted through an oral path, by ingesting contaminated food (uncooked or undercooked meat). It can also be transmitted by direct contact with infected swine, or infected objects, surroundings (fomites). In gravid sows, the virus can infect the piglets through the placenta. It can also be spread through semen during copulation. rarely, it happens that the virus is spread by aerosol in close confinement or by vectors.

The CSF virus can withstand the elements in both pork and processed pork products for months on end, even when the meat is refrigerated, and shockingly for years when it is frozen. Swine can become infected by eating CSF-infected pork meat or by-products.

Studies have shown that in some parts of the European continent, the local wild boar fauna may play an integral role in the genealogy of the disease.

The disease has been widespread due to the legal and illegal transportation of animals, and by feeding swill containing infected tissues to pigs.

Diagnosing CSF

The diagnosis of the classical swine fever virus is based on factors such as clinical signs, serology, virus isolation, and PCR.

The virus can be found in the blood, mucus, urine, feces, and nasal discharges of a once healthy pig. It is mainly replicated in the tonsil region, followed by the endothelial cells, lymphatic organs, and then the bone marrow.

The severity of the disease can vary. It can occur acutely, usually followed by a fatality within a span of two to 25 days. It occurs as a result of swine not being vaccinated. Pigs or hogs are then infected with a highly virulent of one or more strains of the virus.

Symptoms like: fever, depression, anorexia, diarrhea/constipation, conjunctivitis, and neural symptoms such as (paresis, paralysis);, as well as Hyperemia and purpura on the abdomen and ears, are prevalent in this pig fever.

In subacute and chronic cases, the pigs are infected by mildly virulent strains of the virus. In this case, the disease can last for a few weeks or even months. It can affect only some of the animals, showing clinical symptoms. The others may not show any symptoms; however, they will spread the disease nonetheless. In piglets, the virus causes slower growth. 

In gravid sows, there can be abortions, early embryonic death, stillborns, piglets born alive and then they grow slowly and die after a short few weeks.

Pathoanatomic signs

Hemorrhagic lesions, hemorrhagic lymph nodes, petechiae on the epiglottis and the kidneys, infarctions on the spleen, and “Buttons” on the colon.

Testing material and Laboratory tests

Tonsils, spleen, lymph nodes, kidneys, distal part of the ileum

Immunofluorescence, immunoperoxidase, ELISA

Prevention & Control of Classical Swine Fever

• Minimize visitors on your farm and do not allow persons who have had contact with animals in the last five days, especially swine in other countries to have contact with your pigs.
• Newly arriving or returning pigs should be quarantined and isolated for at least 30 days before being reintroduced to the rest of the herd.
• Do not feed uncooked or undercooked garbage or meat products to pigs.

Treatment is not attempted and pigs that have been affected must be sent to the slaughterhouse and the carcasses buried or incinerated.

The first barrier of preventing an outbreak of the CSF is to apply strict and rigorous sanitary prophylaxis, as defined in the OIE Terrestrial Animal Health Code. Good communication between veterinary authorities, veterinary practitioners, and pig farmers, together with a reliable disease reporting system, and hygiene measures protecting domestic pigs from contact with wild boar are the most effective measures to prevent the disease from spreading and causing havoc amongst herds of swine in the area.

When an outbreak occurs, many actions must be set in place urgently:  

• The butchering of all swine on affected farms, commercial or otherwise.
• Safe discarding of carcasses, bedding, etc.
• A comprehensive disinfection plan of pens, houses, and other items that the pigs get into contact with.
• Designation of infected zone, with controlled herd movements.
• A detailed epidemiological investigation, with tracing where possible (up-stream).
• Surveillance of infected zone, and surrounding areas.

How is CSF geographically distributed?

Classical Swine Fever is typically prevalent in continents such as  South and Central America, Asia, Europe, and certain parts of Africa. The good news is that countries such as North America, Australia, and New Zealand are currently free of the disease.

The 1990s saw a large CSF outbreak occur in The Netherlands (1997), Germany (1993-2000), Belgium (1990, 1993, 1994), and Italy (1995, 1996, 1997).

What should I do as a Producer?

Any suspected cases are to be reported with immediate effect!

Key Takeaways

In areas where the disease is prone to becoming endemic, vaccination can prevent the spread thereof. Vaccines used should be produced in accordance with the OIE regulated standards. As the disease is brought under control, vaccination ceases, with continued surveillance. The OIE  defines the necessary requirements for a country or an area to be considered free of the disease.

In disease-free areas, a stamping out policy is applied. This policy has led to the erradication of Classical Swine Fever from North America, and much of Western Europe.

If by chance your favorite animal is a pig, or especially if you have a pet pig, check the video article about Pig Tusk & Hoove Trim by Dr. Evan Antin.