Peste des Petits Ruminants Virus Surveillance in Domestic Small Ruminants, Mozambique (2015 and 2017)

Space-time cluster analysis and maximum entropy modeling of Peste des petits ruminants (PPR) in Türkiye

Peste des petits ruminants (PPR) is an economically important highly serious transboundary disease that mainly occurs in small ruminants such as sheep and goats. The aim of this study was to identify the probability of risk and and space-time clusters of Peste des Petits Ruminants (PPR) in Türkiye. The occurrence of PPR in Türkiye from 2017 to 2019 was investigated in this study using spatial analysis based on geographic information system (GIS). Between these dates, it was determined that 337 outbreaks and 18,467 cases. The highest number of outbreaks were detected in the Central Anatolia region. It was determined that PPR is seen more intensely in sheep compared to goats in Türkiye. In this study, 34 environmental variables (19 bioclimatic, 12 precipitation, altitude and small livestock density variables) were used to explore the environmental influences on PPR outbreak by maximum entropy modeling (Maxent). The clusters of PPR in Türkiye were identified using the retrospective space-time scan data that were computed using the space-time permutation model. A PPR prediction model was created using data on PPR outbreaks combination with environmental variables. Nineteen significant (p < 0.001) space-time clusters were determined. It was discovered that the variables altitude, sheep density, precipitation in june, and average temperature in the warmest season made important contributions to the model and the PPR outbreak may be strongly related with these variables. In this study, PPR in Türkiye has been characterized significantly spatio-temporal and enviromental factors. In this context, the disease pattern and obtained these findings will contribute to policymakers in the prevention and control of the disease.

Structural and functional characterization of peste des petits ruminants virus coded hemagglutinin protein using various in-silico approaches

Peste des petits ruminants (PPR), a disease of socioeconomic importance has been a serious threat to small ruminants. The causative agent of this disease is PPR virus (PPRV) which belongs to the genus Morbillivirus. Hemagglutinin (H) is a PPRV coded transmembrane protein embedded in the viral envelope and plays a vital role in mediating the entry of virion particle into the cell. The infected host mounts an effective humoral response against H protein which is important for host to overcome the infection. In the present study, we have investigated structural, physiological and functional properties of hemagglutinin protein using various computational tools. The sequence analysis and structure prediction analysis show that hemagglutinin protein comprises of beta sheets as the predominant secondary structure, and may lack neuraminidase activity. PPRV-H consists of several important domains and motifs that form an essential scaffold which impart various critical roles to the protein. Comparative modeling predicted the protein to exist as a homo-tetramer that binds to its cognate cellular receptors. Certain amino acid substitutions identified by multiple sequence alignment were found to alter the predicted structure of the protein. PPRV-H through its predicted interaction with TLR-2 molecule may drive the expression of CD150 which could further propagate the virus into the host. Together, our study provides new insights into PPRV-H protein structure and its predicted functions.

Epidemiology, risk factors and molecular characterization of small ruminant morbillivirus in Haryana, India

Peste des petitis ruminants is an economically important transboundary and notifiable viral disease of sheep and goats. In this study, 14 PPR suspected outbreaks among sheep and goats were investigated in four districts of Haryana, India, during July 2020 to October, 2021. The causative agent of the disease; small ruminant morbillivirus was detected by Reverse Transcription Polymerase Chain Reaction targeting full gene sequences of fusion protein gene and confirmed by sequencing. The overall morbidity and cumulative mortality in these outbreaks were 37.56% and 12.09%, respectively. Risk factor analysis identified significant difference in mortality based on age with higher mortality in young ones; 21% as compared to adults; 7.55%. Analysis of the vaccination status revealed significant difference in morbidity and mortality with higher morbidity and mortality in un-vaccinated animals as compared to vaccinated ones. The sequencing and phylogenetic analysis of representative samples revealed that the strains of the present study fall in lineage IV (96.6-99.1%) along with other Indian isolates but made a separate cluster (sub-lineage). The comparison of deduced amino acid (aa) sequence analysis of fusion protein of circulating field strains with reference vaccine strain and other lineage IV strains revealed four N-linked glycosylation sites instead of three. The findings of the present study revealed changes in fusion protein of some of the circulating field strains of SRMV in Haryana, India. Further detailed studies are warranted to delineate the molecular details of these circulating field strains and to evaluate the effectiveness of currently used vaccine against these mutated strains.

Retrospective Characterization of Initial Peste des petits ruminants Outbreaks (2008-2012) in the Democratic Republic of the Congo

Peste des petits ruminants (PPR) is an acute, contagious viral disease of small ruminants, goats and sheep. The Democratic Republic of the Congo (DRC) was a PPR-free country until 2007, although in 2006, scare alerts were received from the east and the southwest of the country, reporting repeated mortalities, specifically in goats. In 2008, PPR outbreaks were seen in several villages in the west, leading to structured veterinary field operations. Blood, swabs and pathological specimens consisting of tissues from lungs, spleens, lymph nodes, kidneys, livers and hearts were ethically collected from clinically infected and/or dead animals, as appropriate, in 35 districts. Epidemiological information relating to major risk factors and socio-economic impact was progressively collected, revealing the deaths of 744,527 goats, which converted to a trade value of USD 35,674,600. Samples from infected and dead animals were routinely analyzed by the Central Veterinary Laboratory at Kinshasa for diagnosis, and after official declaration of PPR outbreaks by the FAO in July 2012, selected tissue samples were sent to The Pirbright Institute, United Kingdom, for genotyping. As a result of surveys undertaken between 2008 and 2012, PPR virus (PPRV)-specific antibodies were detected in 25 locations out of 33 tested (75.7%); PPRV nucleic acid was detected in 25 locations out of 35 (71.4%); and a typical clinical picture of PPR was observed in 23 locations out of 35 (65.7%). Analysis of the partial and full genome sequences of PPR viruses (PPRVs) obtained from lymphoid tissues of dead goats collected in Tshela in the DRC in 2012 confirmed the circulation of lineage IV PPRV, showing the highest homology (99.6-100%) with the viruses circulating in the neighboring countries of Gabon, in the Aboumi outbreak in 2011, and Nigeria (99.3% homology) in 2013, although recent outbreaks in 2016 and 2018 in the western part of the DRC that borders with East Africa demonstrated circulation of lineage II and lineage III PPRV.

Field serological investigation for peste des petits ruminants, foot-and-mouth disease, and bluetongue diseases in illegally introduced animals in Egypt

AIM

In this study, laboratory scoping on the viruses that cause peste des petits ruminants (PPR), bluetongue (BT), and foot-and-mouth disease (FMD) was performed to evaluate the current status of animals illegally introduced into Egypt. This study aims to help control these infectious illnesses and tries to prevent the introduction of other strains of these three viruses to Egypt, as these illnesses spread quickly if not controlled.

MATERIALS AND METHODS

In the year 2018, 62 serum samples were collected and serologically tested through competitive enzyme-linked immunosorbent assays (ELISA) kits to detect antibodies against PPR, BT, and FMD, which are three important transboundary infectious illnesses.

RESULTS

The results indicated that 60 out of 62 serum samples were positive for PPR antibodies (96.7%), 31 out of 62 were positive for FMD antibodies (50%), and 59 out of 62 serum samples were positive for BT antibodies (95%).

CONCLUSION

This study revealed that PPR, FMD, and BT can be introduced into Egypt through the illegal introduction of sheep and goat from neighboring countries. Laboratory diagnostic abilities should be improved for the early detection and control of these illnesses.

Progress to Control and Eradication of Peste des Petits Ruminants in the Southern African Development Community Region

In southern Africa, small ruminants are an important source of nutrition and income to resource-poor small holder farmers. After spreading from West to Central and Eastern Africa, peste des petits ruminants (PPR) emerged in the United Republic of Tanzania in 2008 and has since been reported in Angola, the Democratic Republic of the Congo, and the Comoros. The disease can cause considerable morbidity and mortality in naïve sheep and goat populations and severely impact rural livelihoods, particularly those of women. Gaps in the knowledge of PPR epidemiology still exist, particularly around the role of small-ruminant movement and the role of the abundant wildlife in southern Africa. The capacity of veterinary services to undertake surveillance and control PPR is heterogeneous within the region, with vaccination being limited. The Pan African strategy for the control and eradication of PPR mirrors the Global Strategy and provides the framework for the Southern African Development Community (SADC) region to meet the 2030 goal of eradication. Five countries and one zone within Namibia are officially PPR free according to OIE Standards. Most countries have developed national strategies for the control and eradication of PPR. To strengthen national and regional PPR eradication programme goals, there is a need for a regional risk-based surveillance adapted to infected, high-risk and lower-risk countries that will enable targeted and efficient control, rapid response to incursions and prevention of spread as well as improved preparedness. Continued international and national support will be necessary including laboratory diagnostics and enhancing surveillance capacity to prevent further spread southwards on the continent.