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Background Lumpy Skin Disease (LSD), Sheeppox (SPP) and Goatpox (GTP) are contagious diseases of ruminants with a devastating impact on the livestock industry and trade, also affecting the living conditions of poor rural and small farmers. LSD, SPP, GTP were mainly confined to Africa, the Middle East and Asia, with some sporadic incursions of SPP in Greece and Bulgaria. However, in 2015 the first incursions of LSD occurred in the European Union. Due to their potential for rapid spreading, a highly sensitive and specific serological method for active and passive surveillance of SPP, GTP and LSD is needed. In addition, such a tool could serve for post-vaccination monitoring. Objective The aim of this work was to evaluate recombinants proteins of the capripoxvirus virion for use in an indirect ELISA (iELISA) to detect anti-capripox antibodies in vaccinated and naturally infected small ruminants and cattle sera. Method We have identified, characterized, expressed and purified capripox-virus virion surface protein (CVSP) that react to positive SPP, GTP and LSD sera samples by Western Blot and iELISA. The iELISA was further optimised and evaluated using sera samples from vaccinat-ed, experimentally and naturally infected sheep, goat and cattle. Results Twenty experimentally infected positive and 130 negative LSD, SPP and GTP sera samples were tested and correctly identified using the CVSP iELISA. We tested sera collected at multiple time points from several LSD experimentally infected animals. We observed a time dependant increased in anti-LSD antibody production after day 14 post infection. For specificity, five ORF positive sera were tested. None of the ORF positive sera was positive in the CVSP iELISA. A number of field sera collected during capripoxvirus outbreaks and vaccination campaigns from animals with known infection/vaccina-tion status were tested by the CVSP iELISA and compared to the virus neutralization assay. The complete dataset and results of the field test evaluation will be presented. Conclusion As capripox diseases spread, and to strengthen disease surveillance and control programmes, there is an ever-increasing need for rapid and effective antibody detection assays. The CVSP tested in the pres-ent study demonstrated to be good antigen candidates for the de-velopment of sensitive and specific serological assays. The prototype iELISA developed has the potential to be used as an effective and rapid method for capripoxvirus antibody detection in vaccinated, experimentally and naturally infected sheep, goat and cattle sera.

Background Peste-des-petits ruminants (PPR) is a highly contagious and devastat-ing viral disease affecting sheep, goats, and a large number of spe-cies within the order Artiodactyla. Robust commercial serological and virological diagnostic kits are available to detect PPR infection, but they were mainly developed for domestic small ruminants (goat and sheep) and for high quality, invasive samples sometimes hard to obtain in the field. New tools are needed to detect PPR infection in atypical hosts (e.g. camels, wildlife) and in complex field situations. Here we present adaptation of existing methods and new diagnostic tools to resolve some of these issues. In some regions, farmers are reluctant to have their animals handled and tested for PPR infection. As well, in the case of wildlife survey, animal capture is very costly and demands complicated logistics. Detection of PPR virus in non- invasive samples (feces) can be extremely useful in such cases. Methods and results We adapted methods of RNA extraction, RT-PCR, RT-QPCR and anti-gen capture ELISA to detect PPR viral particles or genetic material from fecal samples. The methods were validated with samples col-lected during an infection experiment. Our protocol was then used with fecal samples obtained in the field in Tanzania in 2015, and compared to results obtained from ocular swab samples taken from the same animals. Another issue is that existing LFD tests used in the field do not allow for direct confirmation by PCR. Here we present a new rapid penside test, produced and distributed by IDvet (France), which can be performed without any lab equipment. Lastly, we also tackled the issue of PPR antibody detection from camelid sera, usually suboptimal because of their particular antibody structure. Results Our results show that virus particles can be detected in fecal sam-ples from 4 days post infection (dpi) until at least 14 dpi. Sensitivity of RT-QPCR from fecal samples was similar to RT-QPCR and lateral flow device (LFD) on ocular swab samples. The penside test was as sensi-tive as the antigen capture ELISA test. Once dried, positive strips can be stored and used later on for confirmation by RT-QPCR or RT-PCR. A simple modification of the protocol of a commercially available competitive ELISA for PPR antibody detection (IDvet) increased the sensitivity of the test on camelid serum. Conclusion These tools will be extremely useful to unravel important questions that still remain about PPR epidemiology, notably the role of atypical host in PPR transmission dynamics.