Peste des petits ruminants (PPR) is a contagious viral disease of domestic small ruminants. It also affects wild ungulates but there are comparatively few studies of the incidence of natural infection, clinical signs and pathology, and confirmation of the virus, and in these species. In this article, we list the wild ungulates in which PPRV infection has been confirmed and summarize available information about the presentation of the disease, its identification, and impact of virus on wildlife populations. Considering recent reports of outbreaks by the World Organization for Animal Health (OIE), it is important to understand the transmission of this disease within wildlife populations in PPR endemic regions.

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Newcastle disease virus (NDV) has a worldwide distribution, causing lethal infection in a wide range of avian species. Affected birds develop respiratory, digestive and neurologic symptoms with profound immunosuppression. Mild systemic Newcastle disease (ND) infection restricted to the respiratory and neurological systems can be observed in humans and other non-avian hosts. Evidence of ND infection and its genome-based detection have been reported in Bovidae (cattle and sheep), Mustelidae (mink), Cercetidae (hamster), Muridae (mice), Leporidae (rabbit), Camelidae (camel), Suidae (pig), Cercophithecidae (monkeys) and Hominidae (humans). Owing to frequent ND outbreaks in poultry workers, individuals engaged in the veterinary field, including poultry production or evisceration and vaccine production units have constantly been at a much higher risk than the general population. A lethal form of infection has been described in immunocompromised humans and non-avian species including mink, pig and cattle demonstrating the capability of NDV to cross species barriers. Therefore, contact with infectious material and/or affected birds can pose a risk of zoonosis and raise public health concerns. The broad and expanding host range of NDV and its maintenance within non-avian species hampers disease control, particularly in disease-endemic settings.

Peste des petits ruminants virus (PPRV) is causing infectious disease with high morbidity and mortality rate in domestic and wild small ruminants of Pakistan with valuable economical losses. The present study was carried out to investigate risk factors of PPRV in domestic small ruminants which were present in the vicinity of wildlife parks. A total of 265 sera samples (27 wild ruminants and 238 domesticated small ruminants) from apparently healthy animals from two different wildlife parks were collected and analysed for PPRV antibodies. Also, 20 nasal swabs from domestic small ruminants showing respiratory signs were collected to check for presence of PPRV antigen. Competitive ELISA revealed highest proportions of anti-PPRV antibodies in domestic small ruminants around the Wildlife Park at Lahore (35%) as compared to Faisalabad (13%), with no existence of PPRV antibodies in tested serum of wild ruminants at these parks. Higher seropositivity was observed in females (25.6%) than in males (5.1%) and in goats (34.5%) compared to sheep (11.2%). The results of N-gene based RT-PCR highlight the absence of PPRV due to lack of current PPR outbreak in the region during study period. Even though grazing was not a significant risk factor, there is still a possibility of wildlife-livestock interactions for feed and water reservoirs, resulting in spillover of PPR to wildlife. Keeping in view the high seropositivity and risk of PPR, vaccination should be adopted to avoid circulation of PPRV among wild and domestic small ruminants (sheep and goats).

Given the global evolutionary dynamics of Newcastle disease viruses (NDVs), it is imperative to continue extensive surveillance, routine monitoring and characterization of isolates originating from natural reservoirs (waterfowls). In this report, we isolated and characterized two virulent NDV strains from clinically healthy mallard (Anas platyrhynchos). Both isolates had a genome of 15,192 nucleotides encoding six genes in an order of 3´-NP-P-M-F-HN-L-5´. The biological characteristics (mean death time: 49.5-50 hr, EID10 ml) and presence of a typical cleavage site in the fusion (F) protein (112R-R-Q-K-R↓F117) confirmed the velogenic nature of these isolates. Phylogenetic analysis classified both isolates as members of genotype VII within class-II. Furthermore, based upon the hypervariable region of the F gene (375 nt), isolates showed clustering within sub-genotype VIIi. Similarity index and parallel comparison revealed a higher nucleotide divergence from commonly used vaccine strains; LaSota (21%) and Mukteswar (17%). A comparative residues analysis with representative strains of different genotypes, including vaccine strains, revealed a number of substitutions at important structural and functional domains within the F and hemagglutinin-neuraminidase (HN) proteins. Together, the results highlight consistent evolution among circulating NDVs supporting extensive surveillance of the virus in waterfowl to better elucidate epidemiology, evolutionary relationships and their impacts on commercial and backyard poultry.