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Human African trypanosomiasis (HAT) or sleeping sickness is a major public health problem, with epidemics occurring during the early part of the 20th century. Control activities of case-finding, treatment, and vector eradication across northern Nigeria with national and international support drastically reduced the prevalence from 14% between 1931 and 1940 to below 1% by 1980. With these successes, the Nigerian Institute for Trypanosomiasis Research (NITR) became underfunded and stopped regular active surveys. In 1985, a new HAT-endemic Abraka focus in Delta State emerged, and the Institute strengthened its surveillance there and in Benue State. In 1988, all outstations were closed, except for the Sleeping Sickness Reference Diagnostic Centre, Gboko, and Benue State. To date, only the Abraka focus has reported HAT case (s) to the WHO in 2012 and 2013. From 2014 to 2017, the Foundation for Innovative New Diagnostics (FIND), in collaboration with NITR and Ministries of Health, introduced intensive passive surveillance in 51 health centres in Delta State aimed at accelerating the control of HAT using rapid diagnostic tools (RDTs), LEDfluorescent microscopy, and molecular methods of LAMP provided free of charge by FIND. The results indicated 157 sero-positives out of 10,093 patients with HAT suspicion index screened but failed to confirm any HAT case by microscopy or molecular analysis. Of interest was the case of HAT exported to the United Kingdom from the Abraka area in 2017, suggesting continuing transmission. To achieve the 2030 HAT global elimination goal, surveillance programmes with sufficient diagnostic capacities must be implemented in Abraka, Delta State, Nigeria. This is not only important, but will also help in generating additional data and information useful in validating the future status of HAT in Abraka, Delta State Nigeria. [ABSTRACT FROM AUTHOR]

African trypanosomosis remains one of the major diseases affecting food security and human healthy living in sub-Saharan Africa. This study screened domesticated animals for the presence of pathogenic trypanosomes in 1,050 slaughtered animals comprising 858 and 100 cattle respectively from Zango and Kawo abattoirs and 92 camels from Zango as Kawo abattoir neither slaughters nor sell camel meat. Both abattoirs are government-owned and located in Kaduna metropolis, Kaduna State, Nigeria. The animals examined were sourced from Bauchi, Yobe, Katsina, Kaduna, Kano, and Chad Republic. Blood samples were collected from each animal at the point of slaughter and examined using the buffy coat technique and Leishman-stained thick film for trypanosome identification. Packed cell volume (PCV) determination was conducted to assess the level of anaemia. Results indicated that 25 cattle and 2 camels (27) had an overall trypanosome infection rate of 2.57%. The trypanosomes observed were mainly Trypanosoma brucei, Trypanosoma congolense, and Trypanosoma vivax. This study showed that sources of livestock slaughtered at various abattoirs can be a useful indicator in quantifying trypanosomosis risk. Continuous sensitization and awareness creation among the herders at the grass-root level is recommended for effective disease management towards increased livestock production and productivity required to sustain the rural economy and improve the livelihoods of the local populace. [ABSTRACT FROM AUTHOR]

The study assessed livestock for human and animal infective trypanosomes in seven remote communities of Iseyin, Oyo State, Nigeria. Blood samples collected at random from 330 cattle and 20 sheep were examined using the buffy coat technique and Leishman stained thin film. Packed cell volume and differential leukocyte counts were determined and interviews conducted. Animals examined showed clinical symptoms; emaciation (2%), rough hair coat (0.57%), body weakness (3.14%), ocular discharge (1.43%), dermatophylosis (0.57%) and ticks (0.57%). Leishman stained thin blood films indicated 34 cattle (9.71%) infected with Trypanosoma congolense, 0% infection in sheep and 100% slides positive for Anaplasma and Babesia parasites with no Trypanosoma brucei species. Anaemia was recorded in male cattle between 1year and 10 years old and was statistically significant (p<0.05). Acute inflammatory responses revealed by neutrophilia, lymphocytopaenia and lymphocytosis; 21.81%, 1.51% and 10% respectively in cattle suggested underlying bacterial or parasitic infections. All (100%) herdsmen confirmed presence of tsetse and other biting flies in bush and canopies around water bodies and stated observable signs and symptoms of trypanosomiasis (samore) which could wipe off the whole herd if untreated. Risk of trypanosome infection remained high as long as the old systems of cattle rearing exist; and urinary schistosomiasis and intestinal ailments due to lack of access to clean and portable water. [ABSTRACT FROM AUTHOR]

The study investigated the presence of Trypanosoma brucei gambiense in livestock to ascertain their reservoir role and also screened for other pathogenic trypanosomes of animals in Tafa Local Government Area of Niger state, Nigeria. A total of 460 livestock comprising (cattle, sheep, goats, and dogs) selected at random were bled, examined using the buffy coat and Giemsa stained thin film and packed cell volume estimated. Questionnaire was filled for each animal on demography, awareness and management practices. An overall prevalence of 2.17% with Trypanosoma brucei, T. congolense, T. vivax and a mixed infection of T. brucei and T. congolense observed microscopically awaiting characterization. Interviews revealed high awareness (82.8%) of tsetse and trypanosomiasis described as bush disease and abortion in four cows. The PCV values were within the normal range, however, a significant decrease (P<0.05) was observed in sheep aged 7months to 4years in two communities. Therefore, the study indicated the presence of T. brucei and other trypanosomes suggesting that animal trypanosomiasis is still a problem to animal health and wellbeing in the study area. The study recommends effective integrated chemotherapy and vector control including livestock rearing under intensive management system to boost livestock production and productivity. [ABSTRACT FROM AUTHOR]

This is a report on the contributions of the Nigerian Institute for Trypanosomiasis (and Onchocerciasis) Research (NITR) towards the elimination of the two Neglected Tropical Diseases. The socio-economic importance of African trypanosomiasis (sleeping sickness in man, Sammoré in domestic animals) and onchocerciasis (River blindness) cannot be overemphasized. The sleeping sickness epidemics in the twentieth century resulted in loss of huge numbers of human lives and desertion of the affected localities and farm lands by survivors. To provide short and long term strategies towards the elimination of the burden of African Trypanosomiasis, the then British Colonial Government established the West African Institute for Trypanosomiasis Research (WAITR) in 1951 to serve the needs of Nigeria, Gold Coast (Ghana), Sierra Leone and The Gambia. WAITR metamorphosed to NITR in 1964 following the nation's independence in 1960. And in 1975, mandate for onchocerciasis research was given to NITR. From its inception to date, NITR had pioneered research works that curbed the outbreaks of Sleeping Sickness, enhanced recognition of the public health importance of onchocerciasis and emphasizing poor funding of research as a great challenge militating against the elimination of endemic parasitic diseases such as trypanosomiasis and onchocerciasis. This paper presents most of the directions and contents of research (diagnostics, therapeutic approaches, etc.) including collaborations NITR had to forge in its efforts to drive the elimination of the two diseases from Nigeria. Future research works are indicated. [ABSTRACT FROM AUTHOR]

This study assessed the prevalence of trypanosomes in cattle at the Kachia Grazing Reserve (KGR) in March and June 2004 and in February 2005. A total of 1293 cattle blood samples were collected at random. The samples were analysed using the buffy coat technique and Giemsa thin blood films for parasite detection and identification. The effects of herd pen location to watering and grazing point's distances (using the global positioning system (GPS)) were determined and mean Packed cell volume (PCV) assessed. Overall, the detected prevalence of trypanosomosis was 8.4%, much higher than the previous prevalence of 5.3% before the present study was conducted. The prevalences in the months of March, June (2004) and February (2005) were 2.3%, 11.6% and 15.4%, respectively. Increased prevalence was associated with proximity of herd pens to watering point's distances (chi(2) for linear trend=4.447, P<0.05), but no association of herd pens to grazing point distances (chi(2)=2.186, P>0.05); suggesting that hydrological network played an important part in trypanosomosis transmission. The mean PCV of parasitaemic and apparasitaemic cattle were respectively 25.99+/-1.82% and 29.31+/-1.70%. The drop in mean PCV was most in 0-1-year age group, 23.47+/-3.10% and was statistically significant (P<0.05), suggesting that anaemia was most pronounced in this age group. Factors that may have contributed to the increased prevalence obtained were collapse of control measures and breed susceptibility. Since, Zebu cattle were the predominant breeds in the reserve, the study advocates effective use of insecticide impregnated screens (traps and targets) with community participation in mind for sustainability. If government intervenes through PATTEC ground spraying of insecticides in the reserve is recommended. In addition, chemotherapeutic and chemoprophylaxis should be systematically used to fight the problem of trypanosomosis in the KGR towards improved livestock production.

Infections with Wuchereria bancrofti causing lymphatic filariasis still represent one of the major health problems in the tropics, with 120 million people infected and over 750 million exposed to this filarial parasite. We have studied lymphatic filariasis infections as part of a multi-parasite survey in a village community in the savannah of northern Nigeria. We analysed serum samples from 341 individuals aged 5-70 years, detecting a W. bancrofti circulating antigen using the commercially available ICT Filariasis card test. The prevalence of infections was 10% and clearly age-dependent, increasing from below 2% in children to over 20% in subjects older than 40 years. Measuring IgG4 antibodies against the recombinant W. bancrofti antigen SXP1 showed that 36% of all tested individuals had been at least exposed to the parasite. Antibody levels also increased very significantly with age. A further analysis measuring Onchocerca volvulus-specific IgG4 antibodies showed a very significant association between infections with O. volvulus and those with W. bancrofti. Our data show that infections with W. bancrofti in Nigeria are still a frequently occurring health problem, since they are more prevalent than previously reported, and that individuals with an O. volvulus infection are more often infected with W. bancrofti than expected statistically., (Copyright 2002 Elsevier Science Ireland Ltd.)

This study evaluated the usefulness of parasite-specific IgG and IgG isotype responses for diagnosing early or pre-patent onchocerciasis in children using sandwich ELISA. The children (n = 199) were aged between 5 and 12 years and living in a meso-endemic area of northern Nigeria. Only five had detectable skin microfilariae. The mean optical density (OD) values of children from the study area were significantly higher than those of normal controls' sera (n = 10, p < 0.01), except for IgG2. There were 145 (73%) children positive for total IgG, 161 (81%) for IgG1, 68 (34%) for IgG3 and 187 (94%) for IgG4 antibodies. The mean OD values of all antibodies tended to increase with age and peaked in the 9-10-year age group, except in the case of IgG3 which peaked at 11-12 years. IgG4 proved most sensitive compared with IgG, IgG1 and IgG3 in all age groups, and was significantly different (p < 0.05). Analysis by sex showed no significant difference between the boys and girls. We conclude that IgG4 serology is a useful diagnostic tool in the assay of early or pre-patent onchocerciasis in children.

The genetic diversity of P. falciparum and multiplicity of infection has been studied in a village in Northern Nigeria at the end of the rainy season, when transmission is high. We analysed blood samples from 104 individuals aged 5-70 years by polymerase chain reaction (PCR) amplifying the gene for the merozoite surface protein MSP2 followed by genotyping based on restriction fragment length polymorphism (RFLP). 94.2% of all samples were parasite positive by PCR and over 80% of those had multiple infections. The age distribution of the average number of parasite clones present in P. falciparum infections showed an initial increase, then reached a peak multiplicity in children 8-10 years of age, and afterwards decreased significantly with age. Mean multiplicity in those 8-10-year-old children was 5.4 clones per carrier. Peak multiplicity and parasite diversity in Nigerian individuals is compared to findings from other study sites in Africa and PNG. The prevalence of IgG antibodies against the circumsporozoite protein (CSP), an indicator for malaria exposure, was over 85% in all age groups showing a high exposure of villagers to P. falciparum. OD values in ELISA were positively correlated with age. There was no correlation between the level of IgG against CSP and the multiplicity of P. falciparum infections determined by PCR of msp2. These results imply that in highly endemic areas multiplicity of infection is not directly correlated with exposure to P. falciparum.