Detection and Genetic Characterization of an Avipox Virus Isolate from Domestic Pigeon (Columba livia domestica) in Morogoro Region, Eastern Tanzania
S. N. Masola *
Department of Research and Technology Development, Tanzania Livestock Research Institute, P.O. Box 202, Mpwapwa, Tanzania and Department of Veterinary Microbiology and Parasitology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
A. Mzula
Department of Veterinary Microbiology and Parasitology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
E. D. Mwega
Department of Veterinary Microbiology and Parasitology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
C. J. Kasanga
Department of Veterinary Microbiology and Parasitology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
P. N. Wambura
Department of Veterinary Microbiology and Parasitology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
*Author to whom correspondence should be addressed.
Abstract
Aim: To determine molecular and evolutionary characteristics of a newly isolated Tanzanian isolate of pigeonpox virus (PGPV).
Study Design: Experimental.
Place and Duration of Study: Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; between November 2011 and May 2014.
Methodology: Samples of cutaneous nodular lesions were collected from 17 pigeons suspected to have pigeonpox in Morogoro (n = 11), Pwani (n = 2) and Dar es Salaam (n = 4) regions; followed by virus isolation, and confirmation by amplification and sequencing of P4b gene. Further the sequence was phylogenetically analyzed for its evolutionary relationship with other related viruses.
Results: PGPV was detected in two samples, both from Morogoro region. Sequence analysis revealed that the Tanzanian PGPV isolate derived in this study was 90 – 99% identical to several avipoxvirus isolates from birds belonging to different species from several countries; for instance the Tanzanian PGPV isolate was 91% identical to each of the Tanzanian fowlpox virus isolates derived in the previous study, and 99% identical to all three PGPV isolates whose sequences were obtained in the GenBank i.e PGPV isolates from India (accession number DQ873811), Egypt (accession number JQ665840) and a PGPV (accession number AY530303) whose country of origin is unknown. Phylogenetic analysis revealed that the Tanzanian PGPV isolate belongs to clade A in subclade A2, sharing a recent common ancestor with members of subclade A3.
Conclusion: Currently, pigeonpox virus is circulating in Morogoro region. The present study warrants the further surveillance/ molecular epidemiology of PGPV in Tanzania in a large-scale.
Keywords: Pigeonpox virus, cutaneous nodular lesions, virus isolation, amplification, sequencing, Tanzania