Feasibility of Onchocerciasis Elimination with Ivermectin Treatment in Endemic Foci in Africa: First Evidence from Studies in Mali and Senegal

The control of onchocerciasis, or river blindness, is based on annual or six-monthly ivermectin treatment of populations at risk. This has been effective in controlling the disease as a public health problem, but it is not known whether it can also eliminate infection and transmission to the extent that treatment can be safely stopped. Many doubt that this is feasible in Africa. A study was undertaken in three hyperendemic onchocerciasis foci in Mali and Senegal where treatment has been given for 15 to 17 years. The results showed that only few infections remained in the human population and that transmission levels were everywhere below postulated thresholds for elimination. Treatment was subsequently stopped in test areas in each focus, and follow-up evaluations did not detect any recrudescence of infection or transmission. Hence, the study has provided the first evidence that onchocerciasis elimination is feasible with ivermectin treatment in some endemic foci in Africa. Although further studies are needed to determine to what extent these findings can be extrapolated to other areas in Africa, the principle of onchocerciasis elimination with ivermectin treatment has been established

Baboons as potential reservoirs of zoonotic gastrointestinal parasite infections at Yankari National Park, Nigeria

Background: Zoonoses pose a risk to public health. Objective: To carry out the investigation of the prevalence of gastrointestinal parasites of baboons, Papio anubis , frequenting the Wikki base Camp in Yankari National Park, Nigeria Method: Formol-ether concentration technique was used to isolate parasite eggs and cysts from faecal samples. Results: Parasites recovered were Ascaris lumbricoides , Ancylostoma duodenale , Strongyloides stercoralis , Fasciola sp, Schistosoma mansoni , Hymenolepis nana , and Trichostrongylus sp, and cysts of protozoan parasites Entomoeba histolytica , E. coli , and Iodamoeba butschii . Conclusion: Most of the parasites identified are known to have high pathologic involvement in humans, implicating the baboons as potential source and reservoirs for human zoonotic parasitic infections although further molecular work would be necessary to ascertain if these gastrointestinal parasites are the same strains that infect human

Determining malaria situation through linelist hospital attendance records in selected communities in Benue State, north-central Nigeria

Knowledge of malaria situation provides useful insights on which effective malaria control strategies can be predicated. The objective of this study was to retrospectively determine the malaria situation in the selected communities through hospital attendance records. In the absence of useable retrospective data, a line list record of hospital attendance was collated and used to provide baseline information on some malariological parameters. Point of service collation resulted in 490 confirmed malaria cases, only 69(14.1%) captured the rural settings while 421(85.9%) represented the urban areas. Rapid Diagnostic Test (RDT) was used for 464(94.7%), microscopy 4(0.8%) and RDT/microscopy accounted for 22(4.5%).Of the four species of human malaria recorded, Plasmodium falciparum peaked with 470(95.9%). Indoor Residual Spray (IRS) was not extensive (3.13%) and Insecticide Treated Nets (ITNs) ownership did not equate usage. Dataset highlights gaps in malaria disease control, the need for universal coverage, and the age long challenge of irregular reporting. Failure to tackle these challenges is a guaranty for unsuccessful elimination and ensures a resurgence of this formidable disease.Keywords: Malaria, morbidity; mortality; Plasmodium; Nigeria

Mapping of lymphatic filariasis in Benue State, Nigeria

An epidemiological mapping was undertaken from December, 2004 to February, 2005 with the aim of determining the prevalence of Wuchereria bancrofti in 18 Local Government Areas (LGAs) of Benue State, Nigeria. A total of 1,830 persons aged 20 years and above were screened for circulating filarial antigen (CFA) using immuno-chromatographic (ICT) whole blood tests. An overall CFA prevalence of 6.5% was recorded in 65% of 20 communities from the 18 LGAs. The results indicate that lymphatic filariasis is widely distributed in the state. Prevalence of infection was significantly (

A guide to the Simulium damnosum complex (Diptera: Simuliidae) in Nigeria, with a cytotaxonomic key for the identification of the sibling species.

<title/> Although approximately 40% of all the people blinded by Onchocerca volvulus are Nigerians, almost nothing was known about the various cytospecies of the blackfly vectors present in Nigeria until 1981. The activation of the Nigerian National Onchocerciasis Control Programme in 1986 (and that programme's initiation of mass distributions of ivermectin in 1991) provided a significant stimulus to understand the biology of the Nigerian vectors but the exploration of any possible differences between the cytospecies has been hampered by a lack of accessible taxonomic information. This review attempts to satisfy that need. There are nine different cytoforms reliably recorded from Nigeria (Simulium damnosum s.s. Nile form, S. damnosum s.s. Volta form, S. sirbanum Sirba form, S. sirbanum Sudanense form, S. soubrense Beffa form, S. squamosum A, S. squamosum B, S. squamosum C and S. yahense typical form), and three more are known from surrounding countries and might be reasonably expected to occur in Nigeria. All of these cytospecies are presumed to be vectors, although there have been almost no identifications of the vectors of O. volvulus in Nigeria. The biogeographical distribution of the cytoforms is broadly similar to that known in other parts of West Africa (although many of the cytoforms remain insufficiently studied). The physico-chemical hydrology of the Nigerian breeding sites of the cytospecies does not, however, correspond to that seen elsewhere in West Africa, and it is not clear whether this might be related to differences in the cytoforms. An illustrated cytotaxonomic key is presented to facilitate and encourage future studies