Diseases

Sheep and Goat Pox Virus

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Control Tools

  • Diagnostics availability

  • Diagnostic kits validated by International, European or National Standards

    No.

  • Diagnostic method(s) described by International, European or National standards

    Routine methods are described in the OIE Manual of Diagnostic Tests and Vaccines

    1. Identification of the agent

    • Nucleic acid recognition (PCR)

    2.  Serological

    • VNT/SNT
    • ELISA (antibody detection)

    GAP : 

    Formal validation of most, if not all, of these tests has not been undertaken (particularly to the level required by the OIE).

  • Commercial potential for diagnostic kits in Europe

    Limited as disease only occurs occasionally in southern Europe.

  • DIVA tests required and/or available

    DIVA for both antigen and antibody are required but are not available.

    GAP :

    There are no DIVA tests or vaccines developed for sheeppox and goatpox.

  • Opportunities for new developments

    Both PCR and ELISA diagnostic kits are commercially available. Quality control studies (sensitivity, specificity, repeatability, reproducibility and accuracy) and approval of the OIE are ongoing. 

    GAPS :

    • Establishing a collection of well-characterised samples from experimentally and naturally infected or vaccinated animals will assist effective test development and validation.
    • Further development and testing of ELISA-based diagnostic tests will help endemic countries to put in place effective control and eradication strategies.
           
  • Vaccines availability

  • Commercial vaccines availability (globally)

    Several live attenuated vaccines are currently available from a number of manufacturers.

    GAP :

    The mechanism of attenuation is unknown for live vaccines.

  • Commercial vaccines authorised in Europe

    Not usually. Live capripoxvirus vaccines have been licenced for use under emergency measures in south-east Europe against LSDV 2015-present.

  • Marker vaccines available worldwide

    No.

    GAP :

    There is no research currently on-going in developing a marker vaccine. 

  • Marker vaccines authorised in Europe

    No.

  • Effectiveness of vaccines / Main shortcomings of current vaccines

    • Inactivated vaccines do not provide long term immunity.
    • Live attenauted capripoxvirus vaccines provide long-term (>1 year) within-genus cross-protection.
    • Poorly attenuated or poorly manufactured vaccines have been marketed.

    GAPS :

    • There is a need for intensive evaluation of immunity levels, either cell mediated or humoral, and how they correlate with protection under field conditions.
    • Quality standards for CPPV vaccines require review.
       
  • Commercial potential for vaccines in Europe

    None.

  • Regulatory and/or policy challenges to approval

    Use of genetically modified vaccines might be problematic in some countries. The field trials may need specific regulation regarding the release of GMOs into the environment.

  • Commercial feasibility (e.g manufacturing)

    No demand in Europe.

  • Opportunity for barrier protection

    Could be used in the event of an incursion into Europe.

  • Opportunity for new developments

    To develop recombinant vaccines based on capripoxvirus as the vector.

    GAP :

    Poxviruses are ideal vaccine vectors that can be used for vaccinating against several diseases using multiple antigens.

  • Pharmaceutical availability

  • Current therapy (curative and preventive)

    None.

  • Future therapy

    Antivirals may play a role but unlikely.

  • Commercial potential for pharmaceuticals in Europe

    None.

  • Regulatory and/or policy challenges to approval

    None.

  • Commercial feasibility (e.g manufacturing)

    Depends on demand.

  • Opportunities for new developments

    Unlikely due to a lack of a profitable market. Nevertheless, several candidate antiviral therapeutics have been developed for use against smallpox virus in the event of a possible pandemic arising through an act of bioterrorism, and these might lead to more ready identification of candidate drugs for use against capripoxviruses in sheep and goats.

  • New developments for diagnostic tests

     

       
  • Requirements for diagnostics development

    Diagnostic tests must be validated and have reasonable sensitivity and specificity.

  • Time to develop new or improved diagnostics

    Years.

  • Cost of developing new or improved diagnostics and their validation

    Cannot be specified as depends on nature of the test.

  • Research requirements for new or improved diagnostics

    • Identification of immunodominant antigens.
    • Identification of diagnostic targets within capripoxvirus genomes suitable for genotyping.
  • Technology to determine virus freedom in animals

    Better understanding of the immune response to SPPV or GTPV infection.

    GAP :

    Develop a DIVA test to distinguish infected and vaccinated animals.

  • New developments for vaccines

  • Requirements for vaccines development / main characteristics for improved vaccines

    • Live-attenuated vaccines currently available are very good at providing protection, no major new developments are required.
    • A vaccine with DIVA capacity would be an advantage, although not essential.
    • All vaccines commercially available should conform to the OIE standards.

    GAPS :

    • The development of new vaccination programmes, rather than new vaccines, and formally evaluate their effectiveness.
    • Identification and characterisation of proteins with putative virulence and host range functions, as well as those involved in modification/evasion of the host immune response, should facilitate the development of a rationally designed live attenuated vaccine.
    • Developing multivalent vaccines.
  • Time to develop new or improved vaccines

    Depending on when a candidate vaccine could be identified the timescale will be 5-10 years. This will involve development, clinical trials and licensing.

  • Cost of developing new or improved vaccines and their validation

    Expensive with the need to develop and undertake all the relevant tests to provide data to enable the product to be authorised. Field trial will be difficult as will be evaluation of the results.

  • Research requirements for new or improved vaccines

    Identification and characterisation of proteins with putative virulence and host range functions, as well as those involved in modification/evasion of the host immune response, should facilitate the development of an improved, “universal” live attenuated vaccine.

       
  • New developments for pharmaceuticals

     

       
  • Requirements for pharmaceuticals development

    Unlikely due to a lack of a profitable market.

  • Time to develop new or improved pharmaceuticals

    Time to develop would depend on the product and the trials necessary to validate the efficacy and safety. Commercial production would then take further time. Five to 10 years seems a realistic timeframe.

  • Cost of developing new or improved pharmaceuticals and their validation

    Expensive but difficult to assess as it will depend on the product and the trials necessary to validate and license.

  • Research requirements for new or improved pharmaceuticals

    A better understanding of the molecular basis of capripoxvirus pathogenesis is required, so that candidate therapeutic agents can be identified. Advances in the development of antiviral therapeutics against smallpox virus might facilitate the identification of candidate drugs for use against SPPV and GTPV.

Disease details

  •  

       
  • Description and characteristics

     

       
  • Pathogen

    • Sheeppox virus
    • Sheeppox virus and GTPV are antigenically and genetically closely related to each other and to Lumpy skin disease virus (LSDV), the third species in the genus Capripoxvirus.
    • SPPV and GTPV share ~96% nucleotide identity over their entire genome length, while SPPV and GTPV share ~97% nucleotide identity to LSDV.

    GAPS :

    • Sequencing of more CPPV isolates from a more representative geographical spread to characterise each species in more detail, and to identify the inter and intraspecies variability.
    • Identify diagnostic targets within capripoxvirus genomes suitable for genotyping.
         
  • Variability of the disease

    • Sheeppox and goatpox are caused by SPPV and GTPV, two species of capripoxvirus. Typically, SPPV and GTPV exhibit host preference, with SPPV causing more severe disease in sheep and GTPV causing more severe disease in goats. However there are some strains which are equally virulent in both species.
    • SPPV and GTPV do not cause disease in any other species.
    • Poxviruses are very stable viruses and naturally occurring mutations are rare.
    • There is some evidence of breed susceptibility to SPPV and GTPV.
    • SPPV and GTPV are found in Africa, the Middle East and Asia, with occasional outbreaks in the south east of Europe.
    • The viruses can be transmitted both directly and indirectly, including vector-borne transmission.

    GAPS :

    • Which viral factors underpin the host preference of SPPV and GTPV, and what are their mechanisms of function?
    • Identification and characterisation of virulence factors of SPPV and GTPV.
    • Why are some breeds of sheep / goat more susceptible than others to SPPV / GTPV?
    • What are the contributions of the different modes of transmission to disease spread?
    • Understand variation in environmental characteristics and management practices as potential drivers for the presence of the virus in some regions.
     
  • Stability of the agent/pathogen in the environment

    Poxviruses survive for many years in dried scabs at ambient temperatures. Virus remains viable in wool for 2 months and in premises for as long as 6 months.

  • Species involved

     

       
  • Animal infected/carrier/disease

    Sheep and goats are the natural hosts of SPPV and GTPV. No carrier status has been recognized following infection with either virus.

    GAPS :

    • Determine the geographic spread, incidence and associated economic impact of sheeppox and goatpox.
    • Assess the role of small ruminant wildlife as a potential reservoir host.
    • What is the epidemiological role of goats in maintaining and transmitting SPPV and vice-versa.
  • Human infected/disease

    No.

  • Vector cyclical/non-cyclical

    • SPPV and GTPV can be transmitted directly from on animal to another, and potentially indirect for example via fomites or contaminated environment.
    • Transmission of SPPV by biting flies has also been demonstrated experimentally. Other poxviruses including LSDV are known to employ a mechanical form of vector-borne transmission.

     GAPS :

    • The importance of arthropod vectors in the spread of disease needs to be investigated.
    • The mechanism of vector-borne spread needs further investigation.
  • Reservoir (animal, environment)

    Sheep and goats are the only hosts.

    GAP :

    Some wild small ruminants are likely susceptible, but solid data in support of this are lacking.

  • Description of infection & disease in natural hosts

     

       
  • Transmissibility

    • Direct or indirect contact with infective material.
    • Via arthropod vectors.

    GAPS :

    • What are the contributions of the different modes of transmission (direct, indirect, vector-borne) to disease spread?
    • More information is required on the mode of vector-borne transmission, particularly identification of the vectors involved, details of the mechanism used, and quantitative parameters.
    • Investigate the role of livestock markets and communal pastures as hubs for disease transmission.
  • Pathogenic life cycle stages

    Not applicable.

  • Signs/Morbidity

    • Infected animals show inappetence and a rise in body temperature, pulse and respiratory rates. In the acute phase (within 24 hours after appearance of the skin lesions) the animals develop conjunctivitis, nasal discharge, and excessive salivation. They may show arched back, hypersensitivity, coughing and pneumonia, constipation and scanty urine. Usually an enlargement of superficial lymph nodes (especially the prescapular lymph nodes) is a prominent feature.
    • One to two days after the onset of fever, skin eruptions appear over the less woolly parts of the body. The lesions undergo macular, papular, vesicular (rare), and pustular stages typical of any pox disease. Papules on the eyelids may cause blepharitis and oedema. Scabs persist for up to 6 weeks and after healing cicatrix may remain. Pox lesions on the mucous membranes of the mouth, eyes, and nose ulcerate leading to mucopurulent discharge and crust formation in the muzzle. In severe cases pox lesions appear throughout the whole respiratory and digestive tracts, and also in other internal organs.
    • Secondary complications include bacterial pneumonia, bacterial dermatitis due to secondary bacterial infection of skin lesions, and myiasis.
    • Severity of disease depends on breed, age, nutritional and immune status, and virus species and strain.

    GAP : 

    Update the data on the clinical expression of the disease, as two forms of disease have been reported.

  • Incubation period

    The incubation period ranges between 8 to 13 days following inoculation. 

    GAP :

    Does incubation period vary according to route of inoculation or dose?

  • Mortality

    The mortality rate varies. In endemic areas may be between 5 and 10%. It can approach 100% in imported sheep which are fully susceptible.

    GAP : 

    Need accurate data on mortality and morbidity rates in endemic areas.

  • Shedding kinetic patterns

    Virus is abundant in skin and mucosal lesions. Virus is excreted in nasal, oral and conjunctival secretions, milk, and possibly urine and faeces.

    GAP :

    Infectivity highest during clinical disease, but role of scabs in transmission is not clear.

  • Mechanism of pathogenicity

    • Pathology is present in the epidermis, dermis and underlying musculature and connective tissue, including haemorrhage, oedema, fibrinonecrotic vasculitis, and necrosis, accompanied by abundant histiocytic cells and fewer neutrophils, lymphocytes and eosinophils.
    • Typical pox lesions are also found in the respiratory and gastrointestinal tracts, as well as in other internal organs including lymph nodes, liver and kidneys.
    • Multiple virus-encoded factors are produced during infection, which influence pathogenesis and disease.

    GAPS :

    The pathogenicity of sheeppox and goatpox is poorly understood. Gaps include:

    • Characterisation of viral proteins with putative virulence and host range functions
    • Characterisation of viral proteins involved in modification/evasion of the host immune response
    • Understanding the factors that determine local vs systemic disease
    • Host immune cells involved in systemic spread in the microenvironment of skin, mucous membranes and other tissues.
     
  • Zoonotic potential

     

       
  • Reported incidence in humans

    Capripoxvirus is not infectious to humans.

  • Risk of occurence in humans, populations at risk, specific risk factors

    None.

  • Symptoms described in humans

    None.

  • Estimated level of under-reporting in humans

    None.

  • Likelihood of spread in humans

    None.

  • Impact on animal welfare and biodiversity

     

       
  • Both disease and prevention/control measures related

    Disease with associated mortality and morbidity is a welfare problem.

  • Endangered wild species affected or not (estimation for Europe / worldwide)

    No.

    GAP : 

    Some wild small ruminants are likely susceptible, but solid data in support of this are lacking.

  • Slaughter necessity according to EU rules or other regions

    Slaughter of the infected herd if disease is found in a previously free country or region (for trade / economic reasons).

  • Geographical distribution and spread

     

       
  • Current occurence/distribution

    Sheeppox and goatpox occur in Africa and Asia, with occasional outbreaks in south east Europe (Greece). 

    GAP :

    Better surveillance tools to study SPPV and GTPV incidence and detect outbreaks.

  • Epizootic/endemic- if epidemic frequency of outbreaks

    Believed to be endemic in many parts of Africa and Asia. Outbreaks occur in countries such as Mongolia, and Greece.

    GAP :

    Better surveillance tools to study SPPV and GTPV incidence and detect outbreaks.

  • Seasonality

    • Evidence from the field suggests the disease can appear at any time of the year, but the importance of outbreaks takes a seasonal appearance which can be different from region to another.
    • Empirical reports from some endemic countries suggest an increase of clinical cases related to management practices and/or traditions that involves congregating animals from different herds/flocks in one location (e.g. moving animals during dry season or festivities)

    GAP :

    A need to better understand seasonal cycles and factors that drive this seasonality.

       
  • Speed of spatial spread during an outbreak

    Can be rapid. 

    GAPS :

    • Impact of co-morbidities on sheeppox and goatpox
    • Understanding the risk factors contributing to spread of disease (animal movements, vector distribution etc).
     
  • Transboundary potential of the disease

    Movement of infected sheep and goats.

    GAPS :

    • A need to identify high risk countries where there is potential spread of disease. e.g. from Turkey into Greece and from China into Vietnam and Mongolia.
    • A need to identify high risk areas within endemic countries in order to apply risk-based surveillance and control.
    • Need to determine the risk associated with sheep and goat products such as skins.
  • Seasonal cycle linked to climate

    No.

  • Distribution of disease or vector linked to climate

    No.

    GAP : 

    Little data currently available.

  • Outbreaks linked to extreme weather

    No.

    GAP :

    No data available.

  • Sensitivity of disease or vectors to the effects of global climate change (climate/environment/land use)

    No.

    GAP :

    The role of arthropod vectors in transmission of disease requires clarification.

  • Route of Transmission

     

       
  • Usual mode of transmission (introduction, means of spread)

    • Sheeppox and goatpox are highly contagious diseases. The viruses are thought to be excreted via aerosols or shedding from skin lesions.
    • Virus is thought to enter animals via the respiratory tract or through cuts and abrasions in skin and mucosae.
    • Short and longer distance spread may occur via contaminated fomites or by biting insects acting as mechanical vectors. 

    GAPS :

    • The role and mechanism of arthropod vectors transmission of the viruses requires clarification.
    • The role of environmental contamination (fomites) in disease transmission requires clarification.
    • The evaluation of potential transmission between sheep and goats present in the same flocks.
  • Occasional mode of transmission

    See above, section “Usual mode of transmission”.

  • Conditions that favour spread

    • Close contact between infected and susceptible animals.
    • Possibly an increase in the number of arthropod vectors

    GAPS :

    Need to evaluate the influence of various potential risk factors:

    • Farm management practices
    • Climatic and environmental conditions
    • Contact with potential wild life reservoirs
    • Abundance of arthropod vectors.
     
  • Detection and Immune response to infection

     

       
  • Mechanism of host response

    • The immune response of sheep and goats to challenge with SPPV and GTPV involves both cell mediated and humoral immune systems.
    • Antibodies (humoral immune response) are sufficient to provide protection from challenge.
    • Recovery from natural infection with one Capripoxvirus species provides immunity against all other species (within-genus cross-protection). 

    GAPS :

    More work required to evaluate:

    • Relative importance of cell mediated and humoral immunity.
    • Correlates of protection.
    • CPPV immune evasion mechanisms.
  • Immunological basis of diagnosis

    Antibody detection can be carried out with virus neutralisation tests or serum neutralisation tests (VNT or SNT), or by using an ELISA, or IPMA.

    • The VNT/SNT is considered the gold-standard method but is time consuming, technically challenging, and requires the use of live virus.
    • There is a Double Antigen ELISA for the detection of antibodies against lumpy skin disease virus (LSDV), sheeppox virus (SPPV) and goatpox virus (GTPV) in serum or plasma from cattle, sheep, goats. There are a number of publications in the scientific literature which evaluate its use.
    • The immunoperoxidase assay (IPA) has recently been published with accompanying validation information. It is cheap and simple to perform.

    GAPS : 

    • No tests to measure the cell mediated immunity to CPPVs are currently available.
    • No DIVA test is available, this is particularly important for disease eradication programmes.
  • Main means of prevention, detection and control

     

       
  • Sanitary measures

    • Elimination of infected and exposed flocks by slaughter;
    • Proper disposal of animals and contaminated material;
    • Cleaning and disinfection of contaminated premises and equipment.

    GAP :

    Further studies are required : 

    • On the survival of the viruses in the environment.
    • Effectiveness of disinfectants used in livestock.
       
  • Mechanical and biological control

    Sheeppox and goatpox can be controlled by vaccination. 

    GAPS :

    • Further studies are required to evaluate vaccine effectiveness in endemic settings.
    • Further studies are required to evaluate and identify cost-effective control measures based on the country status and resources available.
  • Diagnostic tools

    • Virus detection using conventional or real-time PCR.
    • Antibody detection using ELISA or Virus Neutralisation Test/Serum Neutralisation Test (VNT/SNT).

    GAPS:

    • Formal validation of some tests have not been undertaken (particularly to the level required by the OIE).
    • Guidance for post-vaccination monitoring using serological testing is required.
    • Simple methods for genotyping SPPV and GTPV strains are required.
     
  • Vaccines

    • Live and inactivated vaccineshave been used. Live attenuated vaccines are recommended since inactivated vaccines only give short term immunity.
    • Live attenuated vaccines will provide protection against all species of capripoxvirus. Immunity generated following vaccination with live attenuated strains is expected to last more than 1 year.
    • The quality of available CPPV vaccines varies, with reports of some being insufficiently attenuated, some not providing protection, and some contaminated with extraneous agents (pestiviruses).

    GAPS :

    • Inactivated vaccines usually have predominance of intracellular mature virus as production of vaccine requires disruption of infected cells. Extracellular enveloped virus antigens therefore not in vaccine and will not protect.
    • No DIVA vaccines against capripoxviruses have been developed.
    • Quality standards for CPPV vaccines should be reviewed and enforced.
    • See also Section “Mechanical and biological control”.
  • Therapeutics

    Only symptomatic treatment and treatment of secondary infections.

  • Biosecurity measures effective as a preventive measure

    Cleaning and disinfection, separation of flocks, quarantine measures.

  • Border/trade/movement control sufficient for control

    • Special veterinary requirements, restrictions or ban of transfer of live animals or their products from endemic countries to countries free of disease.
    • Restrictions or ban of movement of live animals or animal products during disease outbreaks.
  • Prevention tools

    Vaccination.

    GAP :

    Guidance for post-vaccination monitoring using serological testing is required.

  • Surveillance

    Sheeppox and goatpox are classified as notifiable by the World Organization for Animal Health (OIE). A presumptive diagnosis is usually based on highly characteristic clinical signs, but the diagnosis must be confirmed by laboratory testing.

    GAP :

    Sheeppox and goatpox are classified as notifiable by the World Organization for Animal Health (OIE). A presumptive diagnosis is usually based on highly characteristic clinical signs, but the diagnosis must be confirmed by laboratory testing.

     
  • Past experiences on success (and failures) of prevention, control, eradication in regions outside Europe

    • Successful vaccination is the only effective control in endemic countries.
    • A slaughter policy with movement controls can be effective when the disease is introduced into a previously free country.
  • Costs of above measures

    Although live vaccine against SPPV and GTPV is very cheap to produce the control of the disease is usually expensive in terms of vaccine campaigns or stamping-out and movement controls.

    GAP :

    Formal epidemiological and economic evaluations of different preventive and control measures (vaccination, disinfection, quarantine, stamping out, etc) should be conducted in different settings in order inform policies.

  • Disease information from the OIE

  • Disease notifiable to the OIE

    Yes.

  • Socio-economic impact

  • Zoonosis: impact on affected individuals and/or aggregated DALY figures

    Not applicable.

  • Zoonosis: cost of treatment and control of the disease in humans

    Not applicable.

  • Direct impact (a) on production

    • Capripoxvirus disease has a substantial economic impact on those rural communities that are predominantly reliant on livestock farming for their livelihood, due to morbidity and mortality encountered in susceptible animals; reduction of animal production (weight, milk, wool and cashmere) and economic value of affected animals; and the effect of enforced control measures.
    • Presence of sheeppox and goatpox in a country limits the trade of new breeds and the development of intensive sheep production.
    • At farm level sheeppox and goatpox have an immediate economic impact by reducing animal production and incurring extra costs to treat affected animals, as well as long lasting impact by changing the herd structure and decreasing the value of the herd or flock.
    • Severity of the outbreaks varies depending on level of acquired immunity (naïve vs endemic or vaccinated populations) and control measures implemented. Recent studies suggest that the impact also varies across production systems.

    GAPS :

    • In order to develop control policies aligned with each country’s needs and resources available, further studies are required to better understand farmers’ coping strategies as well as incentives and barriers to control capripoxviruses.
    • Epidemiological investigation during and after sheeppox and goatpox outbreaks are needed in order to quantify and better understand the role of different management practices, geographic characteristics and control measures implemented as potential drivers for capripox viruses’ dynamics and impact.
    • Longitudinal studies in different endemic settings are required in order to better understand both immediate and long-lasting impacts at farm and country level.
     
  • Direct impact (b) cost of private and public control measures

    • Costs of vaccination and vaccination programmes.
    • Palliative treatment with antibiotics to avoid secondary infections is also common.

    GAP :

    Further studies are required to estimate the cost of different control measures and treatments at farm and country level (cost-effectiveness studies).

  • Indirect impact

    There is little information on the macro level effect of sheeppox and goatpox outbreaks and control measures on food supply and prices over time.

    GAP :

    Studies are required to quantify the effect of control policies on food systems at local and regional level.

  • Trade implications

  • Impact on international trade/exports from the EU

    High impact. Standards for movement are specified in the OIE Terrestrial Animal Health Code.

  • Impact on EU intra-community trade

    None apart from sporadic incursions into the EU when movement controls and slaughter campaigns are imposed on regions involved.

     
  • Impact on national trade

    None.

     
  • Main perceived obstacles for effective prevention and control

    • Lack of commercial vaccines availability in some low-middle income countries (LMIC).
    • Lack of an effective veterinary infrastructure in some low-middle income countries (LMIC).

    GAPS :

    • Rapid availability of good quality affordable CPPV vaccines is required.
    • Quality standards for CPPV vaccines require revision and implementation.
    • CPPV vaccine efficacy and effectiveness field studies are required.
    • Further studies to better understand incentives and barriers to control CPPV at country and farm/household level.
         
  • Main perceived facilitators for effective prevention and control

    • CPPV genomes have been sequenced and analysed.
    • Subunit vaccines are being developed for other related poxviruses.
    • Live-attenuated vaccines are cheap and easy to produce, robust, and provide long-lasting protection.

    GAP :

    Recombinant capripox-based vaccines to control more than one small ruminant disease are desirable because it will allow cutting down the cost of vaccination. Field evaluation of these vaccines will be needed when available in a range of endemic countries with different characteristics

Risk

  • Capripoxviruses are one of the potential animal bioterrorist agents as they

    (i) cause high morbidity and mortality,

    (ii) have potential for rapid spread,

    (iii) have potential to cause serious socio-economic consequences and

    (iv) are of major importance in the international trade of animals and animal products. 

    GAP : 

    Capripox has a long incubation period (approximately 7 days). Animals intentionally infected can travel a considerable distance before showing disease, and can therefore disperse and spread disease. Improving understanding of the relationship between immune response and time from exposure would allow implementation of risk-based surveillance before moving or importing animals.

Main critical gaps

  • We need:

    • A highly sensitive and specific ELISA, based on recombinant antigens, with no requirement for infectious reagents to detect antibodies against capripoxviruses in vaccinated animals as well as in infected animals.
    • A simple, validated conventional PCR method for the differentiation of SPPV from GTPV and for the differentiation of SPPV and GTPV from LSDV. Unfortunately, recombination between SPPV and GTPV can complicate identification of the viruses.
    • A new vaccination programme rather than a new vaccine (including education, implementation).
    • Identification and characterisation of proteins with putative virulence and host range functions, as well as those involved in modification/evasion of the host immune response, to facilitate the development of an improved, “universal” live attenuated vaccine.

Conclusion

    • SP and GP are primarily a problem in developing countries. The current research should focus on design and promotion of vaccination campaigns using safe and effective live attenuated vaccines, in combination with education of farmers through extension activities, and effective implementation of regulations to avoid use of poor vaccines.
    • If all these aspects are taken care of well, the control and eradication of the disease will be a reality globally. Like smallpox, it is possible to eradicate capripoxvirus through vaccination.

    GAP :

    SPPV and GTPV eradication would benefit from:

    • Improving the accessibility of molecular diagnostic tools in LMICs.
    • The development of ELISA tests allowing the monitoring and evaluation of vaccination programmes.

Sources of information

  • Expert group composition

    Pip Beard, Pirbright Institute, UK – [Leader].

    Kris De Clercq, Sciensano, Belgium.

    Georgina Limon-Vega, Pirbright Institute, UK.

    Gerelmaa Ullzibat, State Central Veterinary Laboratory, Mongolia

     

     
  • Reviewed by

    Project Management Board

       
  • Date of submission by expert group

    10 November 2020

       
  • References