RAPID COMMUNICATION Occurrence of Dual Infection of Peste-Des-Petits-Ruminants and Goatpox in Indigenous Goats of Central India Y. S. Malik 1 , D. Singh 2 , K. M. Chandrashekar 2 , S. Shukla 2 , K. Sharma 1 , N. Vaid 1 and S. Chakravarti 1 1 Division of Virology, Indian Veterinary Research Institute, Nainital, Uttarakhand, India 2 JN Krishi Vishwa Vidyalaya, Jabalpur, Madhya Pradesh, India Introduction Concurrent infection with two or more pathogens is a common occurrence (Cho et al., 2006; Saravanan et al., 2007; Mondal et al., 2009; Ozmen et al., 2009; Behera et al., 2010), and interactions among multiple pathogens often appear to generate a more severe or chronic out- come than is observed with the individual pathogens by themselves. Still, very little is known about the specific interactions that occur in concurrent infections. Several diseases affect the small ruminant population, the economic backbone of marginal land and landless farmers, particularly in developing countries like India. Among these, peste-des-petits-ruminants (PPR), blue- tongue (BT) and pox are significant. Peste-des-petits-ruminants virus of the genus Morbi- llivirus family Paramyxoviridae (Gibbs et al., 1979) is characterized by fever, erosive stomatitis, conjunctivitis, gastroenteritis and pneumonia and leads to heavy morbidity and mortality (Abu-Elzein et al., 1990). Bluetongue (an orbivirus of family Reoviridae) is a non-contagious, insect- transmitted viral disease of domestic and wild ruminants. In India, since the first report of BT from Maharashtra in 1964 (Sapre, 1964) and PPR from Tamil Nadu in 1989 by Keywords: Peste-des-petits-ruminants virus; Bluetongue; Goatpox; co-infection; epidemiology; cELISA; sELISA; RT-PCR; sequence analysis; Madhya Pradesh Correspondence: Y. P. S. Malik. Senior Scientist, Division of Virology, IVRI Mukteswar Campus, Nainital, Uttarakhand, India. Tel.: +91 5942 286018; Fax: +91 5942 286347; E-mail: malikyps@gmail.com Received for publication November 22, 2010 doi:10.1111/j.1865-1682.2011.01201.x Summary Peste-des-petits-ruminants (PPR), bluetongue (BT) and goatpox (GP) have been well recognized as causes of significant economic losses in the small rumi- nant 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 indi- cated 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 rela- tively low with the majority of other Indian isolates (72.7–93.5%). The detec- tion 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. Transboundary and Emerging Diseases 268 ª 2011 Blackwell Verlag GmbH • Transboundary and Emerging Diseases. 58 (2011) 268–273