Seasonal Abundance and Epidemiological Indices of Potential Plague Vectors <I>Dinopsyllus lypusus</I> (Siphonaptera: Hystrichopsyllidae) and <I>Ctenophthalmus calceatus</I> (Siphonaptera: Ctenophthalmidae) on Rodents Captured From Three Habitat Types of Hatcliffe and Dzivarasekwa Suburbs of Harare, Zimbabwe

Abstract

The seasonal abundance of Dinopsyllus lypusus Jordan and Rothschild and Ctenophthalmus calceatus Waterson (potential vectors of plague in southern Africa) were studied on rodent hosts captured in selected habitat types of two periurban suburbs of Harare, Zimbabwe. Removal trapping was used to capture the rodents, from which fleas were collected and identified. Prevalence (proportion of animals infested) and specific flea index (SFI = number of fleas per animal) were calculated for each species of rodent host. Cohabitation of the two flea species on the host and its implications were also assessed. In total, 1,083 rodents belonging to nine species were trapped and over 97% of the total captures comprised of four species; Mastomys natalensis Smith, Rattus rattus L., Tatera leucogaster Peters, and Rhabdomys pumilio Sparrman. In total, 735 D. lypusus and 335 C. calceatus were recorded on these four common rodent species. Population density of D. lypusus as measured by prevalence and SFI varied from 13.4 to 53.3% and 0.2-1.5, respectively, while that of C. calceatus varied from 8.2 to 26.7% and 0.2-0.6, respectively. For all rodent species captured, both prevalence and SFI of D. lypusus and C. calceatus were highest during the cold-dry season, followed by the hot dry season, with the hot-wet season recording the lowest indices. Overall cohabitation was highest during the cold-dry season and nonexistent during the hot-wet season. Our findings on the abundance and ecology of D. lypusus and C. calceatus suggest that their roles in the transmission of plague in Zimbabwe need further investigation.