Sequential haematological and serum biochemical changes in Black Bengal goats infected with a local isolate of peste des petits ruminants virus from Bangladesh.

BACKGROUND: Knowledge of sequential changes in haematobiochemical parameters of infected animals helps in the formulation of appropriate supportive therapy. OBJECTIVE: We investigated the sequential haematological and biochemical changes in peste des petits ruminants (PPR)-infected Black Bengal goats. METHODS: Goats were either infected with PPR virus (PPRV; n = 8) or sham infected with sterile phosphate-buffered saline (n = 4) via the intranasal route. Blood and sera were collected from both groups at different days post-infection (dpi) and analysed. Goats were sacrificed at different dpi and the amount of PPRV RNA in different tissues was quantified by real-time RT-PCR. RESULTS: The PPRV-infected goats showed mild depression and scanty nasal secretions starting at 4 dpi which became severe with high fever (106°F), dyspnoea, stomatitis, profuse orinasal discharge and diarrhoea at 9-13 dpi. PPRV RNA was detected in different tissues of infected goats. Severe lymphocytic leukopenia (at 18 dpi) was observed in infected goats. Total protein and albumin decreased in infected goats starting at 10 dpi. An elevated level of enzymes (alkaline phosphatase, creatine kinase, aspartate transaminase and alanine transaminase) and metabolites (blood urea nitrogen and urea B) were found in infected goats starting at 7-10 dpi, suggesting damages in the liver and kidneys. PPR-infected goats showed elevated sodium and chloride ions starting at 7 dpi. The majority of infected goats were seroconverted by 14 dpi. CONCLUSIONS: Anti-diarrheal agents, aqua solutions and other medicine to support liver and kidney functions could be considered as supportive therapy against PPRV infection.

Seroprevalence of Peste des petits ruminants in small ruminants in the North Eastern Region of India.

A seroprevalence study of the peste des petits ruminants (PPR) in small ruminants was carried out in the different states (Assam, Manipur, Meghalaya, Mizoram, Nagaland, and Tripura) in the North Eastern Region (NER) of India using serum samples collected from April 2017 to March 2018. A total number of 4,163 sera [sheep (n = 508) and goats (n = 3,655)] collected from 345 epi­units/villages covering 176 municipalities in NER were screened by competitive ELISA kit for the detection of PPR virus antibodies. The results revealed that the seroprevalence of PPR in small ruminants in Assam, Manipur, Meghalaya, Mizoram, Nagaland, and Tripura was 34.3%, 10.3%, 4.7%, 15.7%, 14.7%, and 5.5%, respectively with an overall 14.5% prevalence.Association between the presence of antibodies and goats has been showed to be significant (p < 0.01) at the NER level level and within every single state. This manuscript highlights the need for continuous monitoring of this important disease as for the severe economic impact PPR may have in the affected countries.

Camelids and Cattle Are Dead-End Hosts for Peste-des-Petits-Ruminants Virus.

Peste-des-petits-ruminants virus (PPRV) causes a severe respiratory disease in small ruminants. The possible impact of different atypical host species in the spread and planed worldwide eradication of PPRV remains to be clarified. Recent transmission trials with the virulent PPRV lineage IV (LIV)-strain Kurdistan/2011 revealed that pigs and wild boar are possible sources of PPRV-infection. We therefore investigated the role of cattle, llamas, alpacas, and dromedary camels in transmission trials using the Kurdistan/2011 strain for intranasal infection and integrated a literature review for a proper evaluation of their host traits and role in PPRV-transmission. Cattle and camelids developed no clinical signs, no viremia, shed no or only low PPRV-RNA loads in swab samples and did not transmit any PPRV to the contact animals. The distribution of PPRV-RNA or antigen in lymphoid organs was similar in cattle and camelids although generally lower compared to suids and small ruminants. In the typical small ruminant hosts, the tissue tropism, pathogenesis and disease expression after PPRV-infection is associated with infection of immune and epithelial cells via SLAM and nectin-4 receptors, respectively. We therefore suggest a different pathogenesis in cattle and camelids and both as dead-end hosts for PPRV.

Rapid Detection of Peste des Petits Ruminants Virus (PPRV) Nucleic Acid Using a Novel Low-Cost Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP) Assay for Future Use in Nascent PPR Eradication Programme.

Peste des petits ruminants (PPR) is a disease of small ruminants caused by peste des petits ruminants virus (PPRV), and is endemic in Asia, the Middle East and Africa. Effective control combines the application of early warning systems, accurate laboratory diagnosis and reporting, animal movement restrictions, suitable vaccination and surveillance programs, and the coordination of all these measures by efficient veterinary services. Molecular assays, including conventional reverse transcription-polymerase chain reaction (RT-PCR) and real-time RT-PCR (RT-qPCR) have improved the sensitivity and rapidity of diagnosing PPR. However, currently these assays are only performed within laboratory settings; therefore, the development of field diagnostics for PPR would improve the fast implementation of control policies, particularly when PPR has been targeted to be eradicated by 2030. Loop-mediated isothermal amplification (LAMP) assays are simple to use, rapid, and have sensitivity and specificity within the range of RT-qPCR; and can be performed in the field using disposable consumables and portable equipment. This study describes the development of a novel RT-LAMP assay for the detection of PPRV nucleic acid by targeting the N-protein gene. The RT-LAMP assay was evaluated using cell culture propagated PPRVs, field samples from clinically infected animals and samples from experimentally infected animals encompassing all four lineages (I-IV) of PPRV. The test displayed 100% concordance with RT-qPCR when considering an RT-qPCR cut-off value of CT >40. Further, the RT-LAMP assay was evaluated using experimental and outbreak samples without prior RNA extraction making it more time and cost-effective. This assay provides a solution for a pen-side, rapid and inexpensive PPR diagnostic for use in the field in nascent PPR eradication programme.

Quantifying Levels of Peste Des Petits Ruminants (PPR) Virus in Excretions from Experimentally Infected Goats and Its Importance for Nascent PPR Eradication Programme.

Following the successful eradication of rinderpest, the World Organization of Animal Health (OIE) and the Food and Agriculture Organisation (FAO) have set a goal to globally eradicate Peste des petits ruminants (PPR) by 2030. To support the eradication programme we have quantified the levels of PPR virus (PPRV) nucleic acid excreted in body fluids (blood, feces, saliva, nasal and eye swabs) of PPRV-infected goats to ascertain which days post-infection animals are potentially infectious, and hence direct quarantine activities. The data will also indicate optimal sample strategies to assess presence of PPR infection in the naturally infected herd. Peak PPRV nucleic acid detection in different bodily fluids was between 5 and 10 days post-infection. As such, this period must be considered the most infectious period for contact transmission, although high viral load was observed through RNA detection in nasal excretions from two days post-infection until at least two weeks post-infection. Percentage sample positivity was low both in eye swabs and saliva samples during the early stage of infection although RNA was detected as late as two weeks post-infection. From the individual animal data, PPRV was detected later post-infection in fecal material than in other body fluids and the detection was intermittent. The results from this study indicate that nasal swabs are the most appropriate to sample when considering molecular diagnosis of PPRV.

Peste des petits ruminants virus infection of Black Bengal goats showed altered haematological and serum biochemical profiles.

In Bangladesh, veterinarians often claim to reduce the mortality of natural peste des petits ruminants (PPR) outbreaks with the help of supportive fluid and electrolyte therapy. Information on haematological and biochemical parameters of PPR-infected goats, which is often altered because of associated tissue damages, is necessary to formulate the appropriate supportive therapy. This study determined the haematological and serum biochemical parameters of Black Bengal goats naturally infected with PPR virus. Blood and serum samples from 13 PPR-affected Black Bengal goats from 13 field outbreaks and 5 healthy goats were collected and analysed by routine haematological and biochemical examination. Haematological analysis of PRR-affected goats showed severe anaemia characterised by significant decrease in the values of haemoglobin, total erythrocyte counts (TECs) and packed cell volume (PCV). On the contrary, PPR-affected goats showed marked leucocytosis with absolute increase in lymphocytes and neutrophils counts compared to the healthy goats. Biochemical analysis revealed significant decrease in total protein and albumin level and increased creatine kinase, aspartate transaminase and alanine transaminase that mirrored the gross and histopathological changes in the PPR-affected goats. Significant increase in the values of sodium and chloride ions was found in the sera of PPR-infected goats. Peste des petits ruminants virus altered the haematological and serum biochemical parameters of the infected goats. Antidiarrheal agents with aqua solution together with other drugs to support liver and kidney function could help improve therapy of PPR-infected goats.

A new immunoassay of serum antibodies against Peste des petits ruminants virus using quantum dots and a lateral-flow test strip.

A fast and ultrasensitive test-strip system combining quantum dots (QDs) with a lateral-flow immunoassay strip (LFIAS) was established for detection of Peste des petits ruminants virus (PPRV) antibody. The highly luminescent water-soluble carboxyl-functionalized QDs were used as the signal output and were conjugated to streptococcal protein G (SPG), which was capable of binding to immunoglobulin G (IgG) from many species through an amide bond to capture the target PPRV IgGs. The PPRV N protein, which was immobilized on the detection zone of the test strip, was expressed by transfecting recombinant Bacmid-PPRV-N with Lipofect into Sf9 insect cells. When exposed to PPRV IgG, QD-SPG bound to PPRV N protein, resulting in the formation of a complex that subsequently produced a bright fluorescent band in response to 365 nm ultraviolet excitation. Sensitivity evaluation showed that the QD-LFIAS limit of detection (LOD) for PPRV antibody was superior to competitive enzyme-linked immunosorbent assay (c-ELISA) and the immunochromatographic strip. No cross reaction was observed when the positive sera of bluetongue virus, canine distemper virus, goat pox virus, and foot-and-mouth disease virus were tested. Further evaluation using field samples indicated that the diagnostic specificity and sensitivity of the QD-LFIAS was 99.47 and 97.67 %, respectively, with excellent agreement between QD-LFIAS and c-ELISA. The simple analysis step and objective results that can be obtained within 15 min indicate that this new method shows great promise for rapid, sensitive detection of PPRV IgG for onsite, point-of-care diagnosis and post vaccination evaluation (PVE). Graphical Abstract Ultrasensitive fluorescent QD immunochromotography in combination with recombinant PPRV N protein could be used to detect PPRV antibody in serum.

Enhanced immunosurveillance for animal morbilliviruses using vesicular stomatitis virus (VSV) pseudotypes.

The measurement of virus-specific neutralising antibodies represents the "gold-standard" for diagnostic serology. For animal morbilliviruses, such as peste des petits ruminants (PPRV) or rinderpest virus (RPV), live virus-based neutralisation tests require high-level biocontainment to prevent the accidental escape of the infectious agents. In this study, we describe the adaptation of a replication-defective vesicular stomatitis virus (VSVΔG) based pseudotyping system for the measurement of neutralising antibodies against animal morbilliviruses. By expressing the haemagglutinin (H) and fusion (F) proteins of PPRV on VSVΔG pseudotypes bearing a luciferase marker gene, neutralising antibody titres could be measured rapidly and with high sensitivity. Serological responses against the four distinct lineages of PPRV could be measured simultaneously and cross-neutralising responses against other morbilliviruses compared. Using this approach, we observed that titres of neutralising antibodies induced by vaccination with live attenuated PPRV were lower than those induced by wild type virus infection and the level of cross-lineage neutralisation varied between vaccinates. By comparing neutralising responses from animals infected with either PPRV or RPV, we found that responses were highest against the homologous virus, indicating that retrospective analyses of serum samples could be used to confirm the nature of the original pathogen to which an animal had been exposed. Accordingly, when screening sera from domestic livestock and wild ruminants in Tanzania, we detected evidence of cross-species infection with PPRV, canine distemper virus (CDV) and a RPV-related bovine morbillivirus, suggesting that exposure to animal morbilliviruses may be more widespread than indicated previously using existing diagnostic techniques.

The first report of peste des petits ruminants (PPR) in camels (Camelus dromedarius) in Iran.

In mid-July 2013, an outbreak of peste des petits ruminants (PPR) was observed in a herd of camels after they were imported from Kuwait to the Khuzestan province in southwest of Iran. The clinical signs of the affected animals included sudden death, fever, oral erosion, and ecthyma like lesions, yellowish diarrhea, pneumonia and respiratory distress, enlargement of lymph node, severe dehydration, dermatitis, ulcerative keratitis, and conjunctivitis. Necropsy findings included keratoconjunctivitis, congestion and consolidation of the lung, paleness of the liver, and enlargement and edema of lymph nodes. Histopathological exam revealed degeneration and acute hyperemia of the lungs, fatty change and necrotic foci in the liver, tubular necrosis in the kidneys, and necrotic dermatitis. We used immunocapture enzyme linked immunosorbent assay (ELISA) to confirm peste des petits ruminants virus (PPRV) and differentiate it from rinderpest virus. Then virus genome was studied by molecular analysis for detecting of strain and substrain of the virus. Immunocapture ELISA of all specimens reacted positively against PPRV antigens. Also, reverse transcription polymerase chain reaction (RT-PCR) results in the lung and lymph nodes of the dead camels consolidated the cause of disease to be PPRV. The present study is the first report of the PPRV outbreak in camels in Iran.

First serological and molecular evidence of PPRV occurrence in Ghardaïa district, center of Algeria.

In February 2012, an outbreak of peste des petits ruminants (PPR) was suspected in Ghardaïa district at the center of Algeria. Clinical, serological, and molecular investigations were performed to confirm the occurrence of PPRV. The overall morbidity, mortality, and case fatality rates of the ten flocks investigated were 12.2, 2.5, and 20.3 %, respectively. At the flock level, positivity to PPR was 100, 90, and 100 % by competitive ELISA (c-ELISA), RT-PCR of blood samples, and oculo-nasal swabs, respectively. At the individual levels, the present study showed that out of 186 samples collected from the same animals 17/62 (27.41 %), 14/62 (22.85 %), and 36/62 (58.06 %) were positive by c-ELISA, RT-PCR of blood samples, and RT PCR of oculo-nasal swabs, respectively. The positivity of PPR was significantly higher using RT-PCR of oculo-nasal swabs than c-ELISA and RT-PCR of blood samples. The N gene partial sequence of five PPRV-positive amplicons revealed 100 % homology among them and phylogenetically belonged to lineage IV. The sequences also showed similarity range of 97-99 % with the strains implicated in the Moroccan and Tunisian outbreaks, however, suggesting that a similar strain is circulating across this area of the Maghreb and highlighting the need for a regional control approach.

Sero-epidemiology of Peste des petits ruminants virus infection in Turkana County, Kenya.

BACKGROUND: Peste des petits ruminants (PPR) is a contagious viral disease of small ruminants. Serum samples from sheep (n = 431) and goats (n = 538) of all ages were collected in a cross-sectional study in Turkana County, Kenya. The objective was to estimate the sero-prevalence of PPR virus (PPRV) infection and associated risk factors in both species. PPRV competitive enzyme-linked immuno-sorbent assay (c-ELISA) analysed the presence of antibodies in the samples. All analyses were conducted for each species separately. Multivariable logistic regression models were fitted to the data to assess the relationship between the risk factors and PPRV sero-positivity. Mixed-effect models using an administrative sub-location as a random effect were also fitted to adjust for possible clustering of PPRV sero-positivity. Intra-cluster correlation coefficients (ρ) that described the degree of similarity among sero-positive responses for each species in each of the six administrative divisions were estimated. RESULTS: Goats had a significantly higher sero-prevalence of 40% [95% confidence interval (CI): 36%, 44%] compared to sheep with 32% [95% CI: 27%, 36%] (P = 0.008). Combined sero-prevalence estimates were heterogeneous across administrative divisions (n = 6) (range 22% to 65%) and even more across sub-locations (n = 46) (range 0% to 78%). Assuming that PPRV antibodies are protective of infection, a large pool of PPRV susceptible middle age group (>6 months and < 24 months) in both species was estimated. This was based on the low sero-prevalence in this group in goats (14% [95% CI: 10%, 20%]) and in sheep (18% [95% CI: 13%, 25%]). Regression analysis returned significant risk factors across species: in sheep - vaccination status, age and administrative division; in goats - sex, age, administrative division and sex*age interaction. The intra-sub-location correlation coefficients varied widely across divisions (range <0.001 to 0.42) and across species within divisions. CONCLUSIONS: Biological, spatial and socio-ecological factors are hypothesized as possible explanations for variation in PPRV sero-positivity in the Turkana pastoral ecosystem.

Serological evidence of camel exposure to peste des petits ruminants virus (PPRV) in Nigeria.

Peste des petits ruminants (PPR), a viral disease of sheep and goats, is endemic in Nigeria. There are reports indicating the involvement of peste des petits ruminants virus (PPRV), the causative agent of PPR, in a camel respiratory syndrome in Africa. Considering that camels share the same grazing land and drinking points with other ruminants, this study was undertaken to determine the seroprevalence and extent of PPRV antibodies in Nigerian camels. A total of 1517 camel sera samples were collected from four states (Borno, Kano, Kastina and Sokoto). The seroprevalence was determined by the H-protein-based competitive ELISA. The overall prevalence was 3.36% (51/1517, 95% confidence interval of 2.51-4.39%). There was no significant differences in prevalence between states (p = 0.8921) and between male and female camels (p = 0.7424). The prevalence differed significantly (p < 0.00001) by body condition score; camels with poor body condition score has higher (16.67%) antibody seroprevalence to PPR compared to those with fair and good body condition score. There was a statistically significant difference between camels aged ≤ 5 years and those >5 years (p = 0.0042). These results show occasional transient PPRV infection of camels in Nigeria, and there is the need to include camels among species to be studied in elucidating the epidemiology of the disease in sheep and goats.

Sample type is vital for diagnosing infection with peste des petits ruminants virus by reverse transcription PCR.

Peste des petits ruminants (PPR) diagnosis from suspected samples from sheep and goats was carried out. Buffy coat, tissues, and oculo-nasal swabs were analyzed using nucleoprotein (NP3/NP4) and fusion protein (F1/F2) gene primers, respectively. Analysis of the sample types and primer set revealed that buffy coat are the best type of samples for PPR diagnosis and the use of two set of primers will increase the number of positives.

Coagulation profile, haematological and biochemical changes in kids naturally infected with peste des petits ruminants.

The aim of this study was to examine the coagulation profile in peste des petits ruminant (PPR) in kids. Five kids from a group of 150 animals (72 goats and 78 kids) were brought to the Veterinary Medical Teaching Hospital from a farm in Burdur province (Turkey) with nasal and ocular discharges and diarrhea. Fifteen goats and 41 kids had died due to diarrhea and three kids were presented to the Department of Pathology for diagnosis. Blood samples were taken from 12 ill animals (infected group) for haematological and biochemical analysis. In addition, five healthy kids were examined from another healthy flock (control group). Leukocyte and lymphocyte numbers of infected group showed significant declinations in comparison to control group (≤0.001). Haemorrhages in all organs of digestive system and small haemorrhagic areas in liver were caused to decrease in erythrocyte and haematocrit values (p ≤ 0.001) in infected group. Concentrations of blood urea nitrogen (BUN) (p ≤ 0.01) and creatinine (p ≤ 0.001) in infected group were significantly higher than control group. Compared to control group, significant increases were determined in serum concentrations of alkaline phosphatase (ALP) (p ≤ 0.01), aspartate aminotransferase (AST) (p ≤ 0.001) and alanine aminotransferase (ALT) (p ≤ 0.001) in the infected group. No significant differences were observed between the infected and control groups for serum gamma glutamyl-transferase (GGT) concentration value. In our study, thrombocytopenia (p ≤ 0.001) together with prolonged activated partial thromboplastin time (APTT; p ≤ 0.01) and prothrombin time (PT; p ≤ 0.001) may show that disseminated intravascular coagulopathy which can occur in kids with PPR.

Sample type is vital for diagnosing infection with peste des petits ruminants virus by reverse transcription PCR

Peste des petits ruminants (PPR) diagnosis from suspected samples from sheep and goats was carried out. Buffy coat, tissues, and oculo-nasal swabs were analyzed using nucleoprotein (NP3/NP4) and fusion protein (F1/F2) gene primers, respectively. Analysis of the sample types and primer set revealed that buffy coat are the best type of samples for PPR diagnosis and the use of two set of primers will increase the number of positives.

Occurrence of dual infection of peste-des-petits-ruminants and goatpox in indigenous goats of central India.

Peste-des-petits-ruminants (PPR), bluetongue (BT) and goatpox (GP) have been well recognized as causes of significant economic losses in the small ruminant population of Asia and Africa. We describe here the occurrence of these three in an outbreak noticed in non-descript goats from a subtropical region of central India. An investigation was carried out to confirm the aetiology of the heavy mortality in goats (74.6%, 112/150), with testing of samples from 12 surviving animals exhibiting mixed clinical signs indicative of PPR, BT and GP. Sandwich ELISA was used to detect PPR virus antigen and competition ELISA to detect PPR virus and BT virus antibodies. GP was confirmed on the basis of nodular lesions and an immunodiffusion assay. Eight of the 12 affected animals (66.7%) were positive for PPR virus and BT virus antibodies, and two goats (16.7%, 2/12) exhibiting clinical lesions of pox were also found positive for PPR virus/antibodies and BT virus antibodies, respectively. Although BT virus could not be identified in any sample, detection of BT virus antibodies indicated previous or possibly concurrent infection with BT virus in these goats. The N-gene-based RT-PCR was used to confirm the PPR infection in these goats, and one of the amplicons was sequenced. The sequence and phylogenetic analysis revealed close proximity to PPR virus isolates from Tibet and China, with sequence homology of up to 96.9%. The sequence homology was relatively low with the majority of other Indian isolates (72.7-93.5%). The detection of this new PPR virus sequence indicates the circulation of cross-border strains in this region of India. It is presumed that the heavy mortality observed in goats is possibly attributable to the occurrence of mixed infection of PPR and GP, or PPR, BT and GP.

Pathological, serological, and virological findings in sheep infected simultaneously with Bluetongue, Peste-des-petits-ruminants, and Sheeppox viruses.

In this study, pathological, serological and virological examinations were performed on 15 sheep from a flock of 250 sheep and lambs that suffer from simultaneous naturally occurring BTV, PPRV and SPV outbreaks. SPV was diagnosed macroscopically and histopathologically, BTV was diagnosed by ELISA, and PPRV was diagnosed pathologically and by ELISA. Clinically fever, diarrhea, depression, polypnea, conjunctivitis, lacrimation, rhinitis, erosive stomatitis, edema of eyelids, photophobia, cutaneous eruption with erythematous areas especially noticeable in wool-free parts of the body and axilla lesions evolving into papules were observed. At necropsy, the most effected organs were lungs and gut. Subepicardial hemorrhages were also commonly seen. While typical pox lesions were observed in some lambs, usually fibrinous pleuropneumonia was more prominent lung lesion. SPV and PPRV lesions were seen at the histopathological examination of the lesioned tissues, BT lesions were mild than SPV and PPRV microscopically. Serum and leukocyte samples of 15 animals were examined for PPRV and BTV by ELISA; 5 samples were positive for PPRV and 6 BTV, 4 were positive for both PPRV and BTV simultaneously. One hundred animals died, most were lambs. Mortality rates were 100% in lambs and 80% in the herd.

Post-vaccination antibodies profile against Peste des petits ruminants (PPR) virus in sheep and goats of Punjab, Pakistan.

A total of 70 sheep and 330 goats were selected randomly. All the animals were kept under same housing and management conditions. Serum samples were collected from all the animals and tested for the presence of antibodies against Peste des petits ruminants (PPR) virus using competitive ELISA (cELISA). All the animals were found negative showing percentage inhibition (PI) values <50. The animals were vaccinated against PPR with Nig/75/1 strain vaccine of PPR Serum samples were collected from randomly selected 12 sheep and 30 goats at 10, 30 and 45 days post-vaccination. The samples were subjected to cELISA to determine the presence of antibodies against PPRV. The samples with PI >50 were considered as sero-positive. The sheep found positive at 10, 30 and 45 days post-vaccination were 1(8.3%), 7(58.3%) and 12(100%) respectively. In case of goats 3(10.0%), 29(96.6%) and 27(90.0%) animals gave positive results at 10, 30 and 45 days post-vaccination respectively. Mean PI values in sheep at 10, 30 and 45 days post-vaccination were recorded as 37, 65 and 91 respectively, whereas in goats these values were 43, 78 and 86 respectively.

Seroprevalence of, and risk factors for, peste des petits ruminants in sheep and goats in Northern Jordan.

Peste des petits ruminants (PPR) is an economically important disease that affect sheep and goat industry in Asia and Africa. In this study, we investigated the seroprevalence, and risk factors, of PPR in sheep and goat flocks from five different governorates (Irbid, Jarash, Ajloun, Mafraq and Zarka) located in Northern Jordan. Serum samples from 929 and 400 sheep and goats, respectively, corresponding to 122 sheep flock and 60 goats flock were collected. Seroprevalence was determined using PPR competitive ELISA. Health status and management information were collected using a semi-structured pre-tested questionnaire. The individual true prevalence of PPR in sheep and goats was 29 and 49%, respectively. The flock level true prevalence of PPR was 60 and 74% in sheep and goats, respectively. In both sheep and goat flocks, large flock size, visiting live animals market and inadequate veterinary services were identified as risk factors for PPR seropositivity. Mixed (sheep and goats) raising was identified as a risk factor for PPR seropositivity in sheep flocks only.

Development of an indirect ELISA for the detection of antibodies against Peste-des-petits-ruminants virus in small ruminants.

Peste des petits ruminants (PPR) is an acute, febrile, highly contagious and economically important viral disease of small ruminants. A polyclonal antibody based indirect ELISA was developed for detection of antibodies to PPR virus in the serum samples of goats and sheep using purified PPR viral antigen propagated in Vero cell culture. A threshold (cut-off) value was set as twice the mean of the negative population based on the distribution of known negative serum samples in respect of PPR virus antibodies in the test. A total of 1544 serum samples from goats and sheep were screened by indirect ELISA and competitive ELISA. The indirect ELISA compared very well with competitive ELISA, with a high degree of specificity (95.09%) and sensitivity (90.81%). When compared with virus neutralization test, the present assay had 100% specificity and 80% sensitivity. With serum samples, the assay could clearly differentiate animals from the infected population from uninfected ones. These results suggest that the indirect ELISA may be a good alternative tool to competitive ELISA for seroepidemiological surveys.