Filarial infections in domestic dogs in Lusaka, Zambia

AbstractFilariae are common parasites of dogs in many parts of the world, but little is known about the status of these infections in sub-Saharan Africa. A study was carried out to determine the occurrence and species of filariae among 272 dogs in Lusaka, Zambia. Giemsa stained blood smear and Knott's concentration methods revealed microfilariae in 16 (5.9%) of the dogs. PCR confirmed that most of these dogs had Acanthocheilonema reconditum infection. Ten (4.0%) of the examined dogs were positive for Dirofilaria immitis circulating antigen (by DiroCHEK® test), but D. immitis microfilariae were not identified in any of the dogs and the status of this infection remains unclear. Further studies are needed to explore the occurrence of filariae in Zambian dogs and the zoonotic potential for humans

Sarcoptes mite epidemiology and treatment in African buffalo (Syncerus caffer) calves captured for translocation from the Kafue game management area to game ranches

<p>Abstract</p> <p>Background</p> <p>In Zambia, translocation of wildlife from National Parks to private owned game ranches demands that only animals free of infectious diseases that could adversely affect the expansion of the wildlife industry should be translocated to game ranches. <it>Sarcoptes </it>mange (<it>Sarcoptes scarbiei</it>) has been involved in the reduction of wildlife populations in some species.</p> <p>Results</p> <p><it>Sarcoptes </it>mange (<it>Sarcoptes scarbiei</it>) was detected and eradicated from two herds of African buffalo (<it>Syncerus caffer</it>) calves captured in the Kafue GMA in July 2004 and August 2005. The overall prevalence was estimated at 89.5% (77/86). Sex had no influence on the occurrence and severity of the disease. Of the 86 calves used in the study, 72.1% had good body condition scores, 20.9% were fair and 7.0% were poor. Of the 77 infected calves, 53.2% were mildly infected, 28.6% were moderately and 18.2% were severely infected. Body condition score was correlated to the severity of the infection (r = 0.72, p < 0.000, <it>n </it>= 86) at capture. Eradication of <it>Sarcoptes </it>mites from the entire herd using ivermetcin was dependant on the severity of the infection. The overall ability of ivermectin to clear the infection after the first treatment was estimated at 81.8% (<it>n </it>= 77). It increased to 94.8% and 100% after the second and third treatments respectively.</p> <p>Conclusion</p> <p>This is the first report on the epidemiology and treatment of <it>Sarcoptes </it>mange in African buffaloes in Zambia. This study improves our understanding about <it>Sarcoptes scabiei </it>epidemiology and treatment which will have further applications for the safe animal translocation.</p

New strategies for controlling ticks

Ticks and the diseases they transmit are widely distributed throughout the world, particularly in tropical and subtropical countries. Ticks transmit numerous rickettsial, spirochetal, protozoan and viral pathogens to humans, many of which can produce fatal or debilitating infections. The importance of ticks in animal health and production lies in the enormous economic losses they cause by transmitting a wide variety of pathogens and by direct damage to their hosts. In addition, most livestock-parasitizing tick species are also capable of transmitting disease agents to man. In the developing world, the losses from ticks and tick-borne diseases are not merely economic. In many areas, malnourished people are deprived of animal protein and fat needed to increase their resistance to debilitating infectious diseases.

Mapping the Geographical Distribution of Lymphatic Filariasis in Zambia

<div><p>Background</p><p>Past case reports have indicated that lymphatic filariasis (LF) occurs in Zambia, but knowledge about its geographical distribution and prevalence pattern, and the underlying potential environmental drivers, has been limited. As a background for planning and implementation of control, a country-wide mapping survey was undertaken between 2003 and 2011. Here the mapping activities are outlined, the findings across the numerous survey sites are presented, and the ecological requirements of the LF distribution are explored.</p><p>Methodology/Principal findings</p><p>Approximately 10,000 adult volunteers from 108 geo-referenced survey sites across Zambia were examined for circulating filarial antigens (CFA) with rapid format ICT cards, and a map indicating the distribution of CFA prevalences in Zambia was prepared. 78% of survey sites had CFA positive cases, with prevalences ranging between 1% and 54%. Most positive survey sites had low prevalence, but six foci with more than 15% prevalence were identified. The observed geographical variation in prevalence pattern was examined in more detail using a species distribution modeling approach to explore environmental requirements for parasite presence, and to predict potential suitable habitats over unsurveyed areas. Of note, areas associated with human modification of the landscape appeared to play an important role for the general presence of LF, whereas temperature (measured as averaged seasonal land surface temperature) seemed to be an important determinant of medium-high prevalence levels.</p><p>Conclusions/significance</p><p>LF was found to be surprisingly widespread in Zambia, although in most places with low prevalence. The produced maps and the identified environmental correlates of LF infection will provide useful guidance for planning and start-up of geographically targeted and cost-effective LF control in Zambia.</p></div

Map resulting from the overlay of the thresholded versions of the maps in Figure 4.

<p>The map depicts areas of predicted presence of ≥15% CFA prevalence (brown), ≥5% CFA prevalence (orange+brown) and areas where no or <5% CFA is predicted to be present (light yellow).</p

Properties and sources of the remotely sensed and other environmental predictors used to model LF prevalence in Zambia.

1<p>Moderate Resolution Imaging Spectroradiometer (MODIS); available at <a href="https://lpdaac.usgs.gov/" target="_blank">https://lpdaac.usgs.gov/</a> (accessed February 2012).</p>2<p>Global Land Cover Network (GLCN); available at <a href="http://www.glcn.org/databases/lc_gc-africa_en.jsp" target="_blank">http://www.glcn.org/databases/lc_gc-africa_en.jsp</a> (accessed February 2012).</p>3<p>World Clim - Global Climate data, available at <a href="http://www.worldclim.org/" target="_blank">http://www.worldclim.org/</a> (accessed February 2012).</p>4<p>United States Geological Services (USGS) Digital Elevation Model (DEM) available at: <a href="http://eros.usgs.gov/" target="_blank">http://eros.usgs.gov/</a> (accessed February 2012).</p>5<p>Socioeconomic Data and Applications Center, available at <a href="http://sedac.ciesin.columbia.edu/data/set/wildareas-v2-human-influence-index-geographic" target="_blank">http://sedac.ciesin.columbia.edu/data/set/wildareas-v2-human-influence-index-geographic</a>. (accessed February 2012).</p