Sheeppox and goatpox are smallpox diseases of small ruminants. For humans, sheep and goat pox are harmless.

Endemic in Asia (incl. European part of Russia), Asia Minor, the Middle East and Africa. Sheeppox and goatpox do not occur in Austria or the EU, with the exception of Greece, Bulgaria, and Spain. Sheeppox outbreaks were first reported in sheep in Spain in September 2022.

Sheep and goats. Infection of wild small ruminants with sheep or goat pox viruses is possible.

Infection usually occurs via direct animal-to-animal contact, often via aerosols. Indirect spread via insects (e.g. stable flies, via contaminated stable equipment, tools, objects and transport vehicles is possible due to the longevity of the virus in the environment. Improperly treated animal hides and skins are also important sources of pathogen spread.

4-14 days

High fever (40-42 °C), nasal and eye discharge, pneumonia, disturbance of the general condition, languor, refusal to eat due to painful blisters in the mouth. The mortality rate varies between 50 % and 100 % and is particularly high in young animals.

There is no therapy

Intensive observation or short-term segregation of newly purchased animals or goats and rams newly recruited for mating. Vaccines are available but not licensed in the EU. Prophylactic vaccination is prohibited in all EU countries.

Sheep and goat pox are among the notifiable diseases of small ruminants (category A animal disease). So far, the disease has not occurred in Austria.

Sheep and goat pox are endemic in Africa, the Middle East, Asia Minor (Turkey) and Asia (e.g. in the Asian part of Russia, China, India). Since 2018, there have been repeated outbreaks in the European part of Russia on the border with Finland, Estonia, Latvia, Belarus and Ukraine. In Europe, outbreaks have been reported in Greece (2013-2014, 2015, 2017, 2023) and Bulgaria (2013, 2023). In 2022, the animal disease reached Spain for the first time. Information on the current animal disease situation in Spain can be found in the World Animal Health Information System.

Affected animal species are sheep and goats. Infections of wild small ruminants have been documented. In Europe, the European mouflon has been shown to be a susceptible species. Data onibex (Capra ibex) and chamois(Rubicapra sp.) are lacking. Human infection with the sheep or goat pox virus is not known.

The import of sheep and goats from regions where sheep pox and goat pox are endemic is prohibited. The initial occurrence of these animal diseases in Greece and Bulgaria could be attributed to the illegal movement of individual infected animals in the course of transhumance or immigration movements as well as illegal animal trade (EFSA Journal 2014;12(11):3885.). The initial occurrence in Spain is thought to have been caused by an entry from North Africa. Healthy animals are only moved within the affected EU states of Greece and Bulgaria for the purposes of breeding and slaughter. Other mechanisms of spread over longer geographical distances (e.g. via wild animals, birds or vectors) have not been researched.

The causative agents of sheep and goat pox, the sheep pox virus (SPPV) and the goat pox virus (GTPV), belong to the genus Capripoxvirus. The sheep pox and goat pox viruses are double-stranded, enveloped DNA viruses (size: 170-260nm x 300-450nm). They occur in genetically different strains. Some of these virus strains can be specialised to the animal species named after them; however, some strains can infect both goats and sheep. Phylogenetically, the sheep pox virus and the goat pox virus differ from the lumpy skin disease virus (LSDV), which also belongs to the capripoxviruses; serologically, capripoxviruses cannot yet be differentiated.

The pathogens are spread directly from infected to healthy animals via aerosols contaminated with pathogens through coughing, sneezing and vigorous head shaking. Excretions containing pathogens (nasal and eye secretions, coughing mucus) are spread in the process. Direct transmission of pathogens via open skin wounds on contact with infected animals is also possible. Suckling lambs and fawns can also become infected from infected dams via skin lesions on the udder. Infected animals are already infectious at the first sign of skin lesions.

Indirect transmission occurs via arthropods (e.g. stable flies). Scientific studies on vectors are scarce. Virus-containing excretions in feed, water, wool, in the stable environment and in transporters as well as poorly prepared or untreated animal skins of infected animals contribute to the spread of the disease. The viruses can be detected in the saliva and nasal and ocular fluids of infected animals for up to 64 days, in the skin lesions for up to 30 days, in the crusts that have fallen off the lesions for up to 180 days, in the urine for 15 days and in the faeces for 61 days after infection. The viruses can persist in the environment for long periods of time - e.g. up to 180 days in pastures or 6 months in the shade of a stable building. The viruses are susceptible to temperatures above 70 °C (65 °C/30min., 56 °C/2h). Preferred pH environment is between 6.6 and 8.6. High alkaline or acidic pH destroys most pathogens. 1 % formalin or chloroform, 2-3 % sodium hypochlorite and some other virucides can inactivate the viruses.

Symptoms

The severity of the disease depends on the virulence of the virus strain, the breed and the age of the host animals. The course of the disease and the severity of the symptoms are more pronounced in homologously infected animals. Young animals are more severely affected than older animals; morbidity is 70-90 %, mortality over 50 %. Mortality in lambs and fawns can be almost 100 %. Recovered animals have lifelong immunity to new infections.

Infection of the animals usually occurs via open skin wounds or via the respiratory organs through pathogen-carrying aerosols. The first skin lesions appear 6 days after infection. Most animals are not infectious until the 6th day. The first symptoms are nasal and ocular discharge, fever (40-42 °C), respiratory problems, loss of appetite and depressive behaviour. Skin lesions first appear on the face, around the lip and nose region and on the eyelids. Skin lesions are also often found on the udder and the base of the tail and sometimes under the wool. Smallpox lesions can occur in almost all internal organs - in the oral cavity, nasal cavity, on the tongue, in the lungs and on the mucous membranes of the digestive tract and respiratory tract. Lymph nodes, liver and spleen are affected to a lesser extent. Recovery of the animals is possible after 21 dpi. Although the animals no longer show any clinical symptoms, they can shed pathogens for up to 64 days after infection. The symptoms of the disease are more pronounced in lambs. Due to the painful lesions in the mouth, nose, respiratory tract and digestive tract, the young animals often refuse to eat and starve to death.

Therapy, control

Sheep pox and goat pox are notifiable animal diseases. The control of both diseases is therefore based on

• preventing the introduction and spread of the pathogen due to trade restrictions with regard to animal trade and trade in animal products from affected countries
• early detection of the diseases
• In the event of an epidemic, measures prescribed by the authorities (e.g. the "stamping out" method (culling of infected and suspected animals))

If sheep and goat pox occurs, restrictions on the movement of animals and animal products as well as the establishment of protection zones around outbreak centres or other disease-specific restrictions are to be expected. After the culling of affected livestock, intensive cleaning and disinfection of the stables and a waiting period before re-stocking are prerequisites for re-housing. The observation and examination of sentinel animals is important for the further occurrence of infections.

Attentuated live vaccines are available, but these are not authorised in the EU. Diagnostically, it is possible to differentiate between vaccinated animals and animals infected with a field strain in SPP; this is not possible with GTP.

Sample type:

Live animals:

• Skin lesions and/or skin crusts.
• Salivary fluid (native in tubes or swab possible - no bacteriological swab transport media).
• Nasal and ocular fluid (with swab - no bacteriological swab transport media)
• Blood (EDTA/Heparin) and serum

Carcasses (dead):

• Whole carcass
• skin lesions and/or skin crusts
• Lymph nodes
• Spleen
• Lungs and altered regions of the respiratory tract
• Nasal fluid (with swab - no bacteriological swab transport media).

Samples can be sent to the National Reference Laboratory for Capripox (Institut für veterinärmedizinische Untersuchungen Mödling) via the official veterinarian.

Detection methods:

• Molecular biological methods (PCR)
• Detection of antibodies by ELISA
• Serum neutralization test (SNT)
• Virus cultivation in cell culture (for research purposes only)

The diagnostic methods are also used in exclusion diagnostics. Exclusion diagnostics not only allows early detection of an epidemic, but also serves to maintain the competence of laboratory diagnostic tests.

Differential diagnosis

Bluetongue, foot-and-mouth disease, plague of small ruminants, lip bark, ovine herpesvirus 2 (OvHV-2) infections, idiopathic ulceration, moderate limp, insect bites, photosensitivity.

Further information - useful references

Consumer health communication platform (KVG) - sheep and goat pox: www.verbrauchergesundheit.gv.at/tiere/krankheiten/schaf_ziegenpocken.html

World Organisation for Animal Health: www.woah.org

WOAH sheep and goat pox fact sheet: https://www.woah.org/en/disease/sheep-pox-and-goat-pox/

WAHIS: https://wahis.woah.org/#/home

EFSA: www.efsa.europa.eu/de

EFSA: Disease profiles:(https://animal-diseases.efsa.europa.eu/)- Sheep and GoatPox: https://animal-diseases.efsa.europa.eu/SPPV

Food and Agriculture Organization (FAO): https://www.fao.org/home/en

Specific Diseases of sheeps and Goats: https://www.fao.org/3/t0756e/T0756E06.htm