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Background: Malaria is a leading cause of mortality in children aged 5 years and below in Nigeria. Treatment guidelines stipulate among other recommendations, testing by microscopy or a rapid diagnostic test (RDT) before treatment. Non-adherence to these guidelines portends a challenge, especially among vulnerable under-five children. This study explored the factors influencing Nigerian public health workers' (HWs) adherence to these guidelines in under-five children., Methods: A review of literature published between 2011- 2023 was conducted on Web of Science, Ovid Embase, Medline, Global Health, CAB Abstracts, Scopus, and Global Index Medicus. Data was extracted and analyzed under 4 themes: diagnosis, compliance with test results, use of recommended treatment, post-treatment counselling and severe malaria management., Results: Nineteen (19) studies were included for review. Training and supervision, RDT and antimalarial availability, good knowledge of, and positive perception of RDTs promoted adherence to mRDT use. A lack of confidence in RDTs and age (≥ 40 years) fuelled presumptive treatment, especially among clinicians. mRDT and artemisinin-based combination therapy (ACT) stockouts dissuaded HWs from adhering to case management guidelines. Caregiver pressure for treatment was identified as a barrier to compliance with test results., Conclusions: It is important to design context-specific strategies to improve adherence to guidelines for malaria case management, especially in under-five children. Training on the guidelines should be tailored, needs-based, and continuous, and HWs should be supportively supervised in implementing case management. Maintaining an adequate supply of quality-assured mRDTs and antimalarials can facilitate adherence to the guidelines., Competing Interests: The authors declare no competing interests., (Copyright © 2024 Ezenyi et al.)

The control of African trypanosomiasis (AT) in Eastern and Southern Africa, including Zambia, faces huge challenges due to the involvement of wild and domestic animal reservoirs. Free-roaming dogs in wildlife-populated and tsetse-infested villages of Zambia's Mambwe district are exposed to infectious tsetse bites. Consuming fresh raw game meat and bones further exacerbates their risk of contracting AT. We focus on the reservoir role of such dogs in maintaining and transmitting diverse species of trypanosomes that are infective to humans and livestock in Zambia's Mambwe district. A cohort of 162 dogs was enrolled for follow-up at 3 different time points from June to December 2018 in selected villages of Malama, Mnkhanya, and Nsefu chiefdoms of Mambwe district, eastern Zambia. Blood and serum were screened for AT by microscopy, GM6 ELISA, PCR (ITS1 and SRA), and Sanger sequencing. Out of the 162 dogs in the cohort, 40 were lost to follow-up and only 122 remained traceable at the end of the study. GM6 ELISA detected Trypanosoma antibodies in 121 dogs (74.7%) and ITS1-PCR detected DNA involving single and mixed infections of T. congolense, T. brucei, and suspected T. simiae or T. godfreyi in 115 dogs (70.9%). The human-infective T. b. rhodesiense was detected by SRA PCR in 67 dogs (41.4%), and some sequence data that support the findings of this study have been deposited in the GenBank under accession numbers OL961811, OL961812, and OL961813. Our study demonstrates that the Trypanosoma reservoir community in Zambia is wider than was thought and includes domesticated dogs. As dogs are active carriers of human and livestock-infective trypanosomes, they pose a risk of transmitting AT in endemic villages of Mambwe district as they are neglected and left untreated. To fully bring AT under control, countries such as Zambia where the role of animal reservoirs is important, should not limit their prevention and treatment efforts to livestock (especially cattle) but also include dogs that play an integral part in most rural communities., (© 2024. The Author(s).)

Good dog-keeping practices and access to veterinary care are essential for the well-being of dogs. As the main causes of morbidity and mortality in the rural canine population in Zambia are poorly understood, we followed a cohort of 162 indigenous dogs for six months in wildlife-populated and tsetse-infested villages of Mambwe district, eastern Zambia to gain deeper insights. Dogs lacked basic home and veterinary care, they were often starved and burdened with ticks, and some passed live adult worms in their stool. The frequent exposure of dogs to tsetse bites and consumption of fresh raw game meat and bones puts them at greater risk of acquiring African trypanosomiasis. Nearly 20 % of dogs were lost to follow-up, with the main causes being poor health (58.1 %), predation by wild carnivores (29 %), and owner culling or euthanasia (12.9 %). We observed that indigenous dogs' general well-being and survival were largely influenced by their environment, infectious diseases, injuries sustained during interaction with conspecifics and wildlife, and community attitudes and practices associated with dog ownership., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

A longitudinal study was conducted within a cattle ranch in Gabon to determine the diminazene aceturate (Berenil) index (DAI) in a group of Zebu, raised under low tsetse density; this measure providing an assessment of trypanosomiasis risk. The objective was to evaluate the trypanosomiasis pressure thus informing trypanosomiasis control methods and cattle management. Twenty female adult Zebu were monitored for 24 weeks during the dry season. Blood samples were collected on a weekly basis and subjected to parasitological and haematological analysis (n = 480), using the buffy-coat method and the packed cell volume value (PCV), respectively, infected animals were treated with a single intramuscular injection of diminazene aceturate (8 mg/kg). Twenty-nine single infectious events were recorded and a DAI of 1.45 was calculated. Two trypanosome species were identified: Trypanosoma congolense (96.2%) and Trypanosoma vivax (3.8%). The mean PCV value of the infected animals was lower (26.6) compared to non-infected animals (32.0). This study shows that DAI may be a useful tool to assess trypanosomiasis. However, this is a time-consuming method that may be improved by using randomly selected sentinel animals to adapt the chemoprophylactic schemes, hence decreasing the costs and the drug resistance risk.

Background: Uganda has suffered from a series of epidemics of Human African Trypanosomiasis (HAT), a tsetse transmitted disease, also known as sleeping sickness. The area affected by acute Trypanosoma brucei rhodesiense HAT (rHAT) has been expanding, driven by importation of infected cattle into regions previously free of the disease. These regions are also affected by African Animal Trypanosomiasis (AAT) demanding a strategy for integrated disease control., Methods: In 2008, the Public Private Partnership, Stamp Out Sleeping Sickness (SOS) administered a single dose of trypanocide to 31 486 head of cattle in 29 parishes in Dokolo and Kaberamaido districts. This study examines the impact of this intervention on the prevalence of rHAT and AAT trypanosomes in cattle from villages that had (HAT +ve ) or had not (HAT -ve ) experienced a recent case of rHAT. Cattle herds from 20 villages were sampled and screened by PCR, pre-intervention and 6-months post-intervention, for the presence or absence of: Trypanosoma brucei s.l.; human infective T. b. rhodesiense; Trypanosoma vivax; and Trypanosoma congolense savannah., Results: Post-intervention, there was a significant decrease in the prevalence of T. brucei s.l. and the human infective sub-species T. b. rhodesiense in village cattle across all 20 villages. The prevalence of T. b. rhodesiense was reduced from 2.4% to 0.74% (P < 0.0001), with the intervention showing greater impact in HAT -ve villages. The number of villages containing cattle harbouring human infective parasites decreased from 15/20 to 8/20, with T. b. rhodesiense infection mainly persisting within cattle in HAT +ve villages (six/eight). The proportion of T. brucei s.l. infections identified as human infective T. b. rhodesiense decreased after the intervention from 8.3% (95% CI = 11.1-5.9%) to 4.1% (95% CI = 6.8-2.3%). Villages that had experienced a recent human case (HAT +ve villages) showed a significantly higher prevalence for AAT both pre- and post-intervention. For AAT the prevalence of T. vivax was significantly reduced from 5.9% to 0.05% post-intervention while the prevalence of T. congolense increased from 8.0% to 12.2%., Conclusions: The intervention resulted in a significant decrease in the prevalence of T. brucei s.l., human infective T. b. rhodesiense and T. vivax infection in village cattle herds. The proportion of T. brucei s.l. that were human infective, decreased from 1:12 T. brucei s.l. infections before the intervention to 1:33 post-intervention. It is clearly more difficult to eliminate T. b. rhodesiense from cattle in villages that have experienced a human case. Evidence of elevated levels of AAT in livestock within village herds is a useful indicator of risk for rHAT in Uganda. Integrated veterinary and medical surveillance is key to successful control of zoonotic rHAT.

Introduction: Human African trypanosomiasis (HAT) comprises two fatal parasitic diseases. Uganda is home to both chronic T. b. gambiense (gHAT) and the acute zoonotic form T. b. rhodesiense (rHAT) which occur in two large but discrete geographical foci. The area affected by rHAT has been rapidly expanding due to importation of T. b. rhodesiense infected cattle into tsetse infested but previously HAT free districts. Migration of rHAT has resulted in a considerable human health burden in these newly affected districts. Here, we examined the impact of a single, district-wide, mass chemotherapeutic livestock intervention, on T. b. rhodesiense prevalence in cattle and on incidence and distribution of human rHAT cases in Kamuli and Soroti districts in eastern Uganda., Methods: A single mass intervention in domestic cattle (n=30,900) using trypanocidal drugs was undertaken in November and December 2002 under the EU funded Farming in Tsetse Controlled Areas (FITCA) programme. The intervention targeted removal of the reservoir of infection i.e. human infective T. b. rhodesiense parasites in cattle, in the absence of tsetse control. Interventions were applied in high-risk sub-counties of Kamuli district (endemic for rHAT) and Soroti district (where rHAT has been recently introduced). The prevalence of T. brucei s.l. and the human infective subspecies, T. b. rhodesiense in cattle (n=1833) was assessed before and 3 and 12 months after intervention using PCR-based methods. A combination of descriptive statistical analysis and spatial scan statistics were applied to analyse rHAT cases reported over a 5-year period (January 2000-July 2005)., Results: A single intervention was highly effective at removing human infective T. b. rhodesiense parasites from the cattle reservoir and contributed to a significant decrease in human rHAT cases. Intervention coverage was higher in Kamuli (81.1%) than in Soroti (47.3%) district but despite differences in coverage both districts showed a reduction in prevalence of T. b. brucei s.l. and T. b. rhodesiense. In Kamuli, the prevalence of T. brucei s.l. decreased by 54%, from 6.75% to 3.11%, 3, months post-intervention, rising to 4.7% at 12 months. The prevalence of T. b. rhodesiense was 3% pre-intervention and no T. b. rhodesiense infections were detected 3 and 12, months post-treatment. In Soroti, the prevalence of T. brucei s.l. in cattle decreased by 38% (from 21% to 13%) 3 months after intervention decreasing to less than 10% at 12 months. The prevalence of T. b. rhodesiense was reduced by 50% at 12-months post-intervention (6%-3%). Most notably, was the impact of the intervention on the population dynamics between T. b. brucei and human infective T. b. rhodesiense. Before intervention in Kamuli district 56% of T. b. brucei s.l. circulating in cattle were T. b. rhodesiense; at both 3 and 12 months after intervention none of the re-infecting T. b. brucei s.l. were human infective, T. rhodesiense. For human rHAT cases, there was a seven-fold decrease in rHAT incidence after intervention in Kamuli district (5.54 cases/1,000 head of population 2000-2002 to 0.76 cases/1,000, 2003-2005). Incidence data suggests that the intervention had minimal impact on the number of rHAT cases in Soroti overall, but showed a significant decrease in the seasonal peak of cases in the year following treatment., Conclusion: A single intervention, targeted at cattle, introduced at district level, in the absence of tsetse control, was highly effective at removing human infective rHAT parasites from the cattle reservoir and contributed to a significant decrease in human rHAT cases. The differential impacts observed between the two districts are related to both the different stages of rHAT endemicity in the districts, and levels of intervention coverage achieved in the cattle population. Treatment of cattle to remove the reservoir of rHAT infection offers a promising and cost effective approach for the control of rHAT. It is important that cattle are treated before relocation to prevent possible merger of the two HAT foci, which would complicate diagnosis and treatment of both gHAT and rHAT., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

Introduction: Sleeping sickness or Human African Trypanosomiasis (HAT) is a neglected tropical disease of public health importance across much of Sub-Saharan Africa. In Uganda, chronic T. b. gambiense HAT (gHAT) and acute T. b. rhodesiense HAT (rHAT) occur in two large but discrete geographical foci. Both forms are difficult to diagnose, expensive to treat and ultimately fatal in the absence of treatment. The area affected by zoonotic rHAT has been steadily expanding, placing a high burden on local health systems. HAT is a disease of neglected populations and is notorious for being under-reported. Here we examine the factors that influence passive rHAT surveillance within the district health system in four Ugandan districts into which the disease had recently been introduced, focusing on staff knowledge, infrastructure and data management., Methods: A mixed methods study was undertaken between 2011 and 2013 in Dokolo, Kaberamaido, Soroti and Serere districts to explore health facility capacity and clinical service provision, diagnostic capacity, HAT knowledge and case reporting. Structured interviews were undertaken with 86 medical personnel, including clinicians, nurses, midwives and technicians across 65 HC-II and HC-III medical facilities, where the health infrastructure was also directly observed. Eleven semi-structured interviews were undertaken with medical staff in each of the three designated HAT treatment facilities (Dokolo, Lwala and Serere HC-IV) in the area. HAT treatment centre case records, collected between 2009 and 2012, were analyzed., Results: Most medical staff in HC-II and HC-III facilities had been made aware of HAT from radio broadcasts, newspapers and by word of mouth, suggestive of a lack of formal training. Key knowledge as regards the causative agent, clinical signs and that HAT drugs are provided free of charge was lower amongst HC-II than HC-III staff. Many respondents did not know whether HAT was endemic in their district. In rHAT specialist treatment centres, staff were knowledgeable of HAT and were confident in their ability to diagnose and manage cases. Between 2009-2012, 342 people were diagnosed in the area, 54% in the late stage of the disease. Over the period of this study the proportion of rHAT cases identified in early stage fell and by 2012 the majority of cases identified were diagnosed in the late stage., Conclusion: This study illustrates the critical role of the district health system in HAT management. The increasing proportion of cases identified at a late stage in this study indicates a major gap in lower tier levels in patient referral, diagnosis and reporting that urgently needs to be addressed. Integrating HAT diagnosis into national primary healthcare programs and providing training to medical workers at all levels is central to the new 2030 WHO HAT elimination goal. Given the zoonotic nature of rHAT, joined up active surveillance in human and animal populations in Uganda is also needed. The role of the Coordinating Office for Control of Trypanosomiasis in Uganda in implementing a One Health approach will be key to sustainable management of zoonotic HAT., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Identifying hosts of blood-feeding insect vectors is crucial in understanding their role in disease transmission. Rhodesian human African trypanosomiasis (rHAT), also known as acute sleeping sickness is caused by Trypanosoma brucei rhodesiense and transmitted by tsetse flies. The disease is commonly associated with wilderness areas of east and southern Africa. Such areas hold a diverse range of species which form communities of hosts for disease maintenance. The relative importance of different wildlife hosts remains unclear. This study quantified tsetse feeding preferences in a wilderness area of great host species richness, Serengeti National Park, Tanzania, assessing tsetse feeding and host density contemporaneously., Methods: Glossina swynnertoni and G. pallidipes were collected from six study sites. Bloodmeal sources were identified through matching Cytochrome B sequences amplified from bloodmeals from recently fed flies to published sequences. Densities of large mammal species in each site were quantified, and feeding indices calculated to assess the relative selection or avoidance of each host species by tsetse., Results: The host species most commonly identified in G. swynnertoni bloodmeals, warthog (94/220), buffalo (48/220) and giraffe (46/220), were found at relatively low densities (3-11/km2) and fed on up to 15 times more frequently than expected by their relative density. Wildebeest, zebra, impala and Thomson's gazelle, found at the highest densities, were never identified in bloodmeals. Commonly identified hosts for G. pallidipes were buffalo (26/46), giraffe (9/46) and elephant (5/46)., Conclusions: This study is the first to quantify tsetse host range by molecular analysis of tsetse diet with simultaneous assessment of host density in a wilderness area. Although G. swynnertoni and G. pallidipes can feed on a range of species, they are highly selective. Many host species are rarely fed on, despite being present in areas where tsetse are abundant. These feeding patterns, along with the ability of key host species to maintain and transmit T. b. rhodesiense, drive the epidemiology of rHAT in wilderness areas., Competing Interests: The authors have declared that no competing interests exist.

In April 2008, whole blood samples were collected from 36 dromedary camels in Sokoto, North-western Nigeria. Following PCR and reverse line blotting, twenty-two samples (61%) resulted positive for Ehrlichia/Anaplasma spp. and three (8%) for Theileria/Babesia spp., with three (8%) cases of co-infections being found. Both sequence and BLAST analyses identified Ehrlichia/Anaplasma spp. and Theileria/Babesia spp. positive cases as Anaplasma platys and Theileria ovis, respectively. This is the first report of the detection of A. platys and T. ovis in camels from sub-Saharan Africa. The epidemiological relevance of this finding is enhanced by the close living of these animals with both dogs and small ruminants. The high prevalence detected for A. platys suggests a possible role of camels as carriers of this infection., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Ticks and tick-borne diseases undermine cattle fitness and productivity in the whole of sub-Saharan Africa, including Nigeria. In this West African country, cattle are challenged by numerous tick species, especially during the wet season. Consequently, several TBDs are known to be endemic in Nigerian cattle, including anaplasmosis, babesiosis, cowdriosis and theilerioris (by Theileria mutans and Theileria velifera). To date, all investigations on cattle TBDs in Nigeria have been based on cytological examinations and/or on serological methods. This study aimed to ascertain the occurrence of tick-borne pathogens of veterinary and zoonotic importance in cattle in Nigeria using molecular approaches., Methods: In October 2008, 704 whole blood samples were collected from indigenous cattle in the Plateau State, Nigeria. Analysis for tick-borne pathogens was conducted by means of PCR-based reverse line blotting (RLB) and sequencing targeting a panel of five genera of microorganisms (i.e. Babesia, Theileria, Anaplasma, Ehrlichia and Rickettsia spp.)., Results: In total, 561/704 (82.6%) animals were found infected, with 465 (69.6%) of them being infected by two or more microorganisms, with up to 77 possible combinations of pathogens detected. Theileria mutans was the most prevalent microorganism (66.3%), followed by Theileria velifera (52.4%), Theileria taurotragi (39.5%), Anaplasma marginale (39.1%), Anaplasma sp. (Omatjenne) (34.7%), Babesia bigemina (7.9%), Anaplasma centrale (6.3%), Anaplasma platys (3.9%), Rickettsia massiliae (3.5%), Babesia bovis (2.0%) and Ehrlichia ruminantium (1.1%). Calves were found significantly less infected than juvenile and adult cattle., Conclusions: This study provides updated, molecular-based information on cattle TBDs in Nigeria. The molecular approach employed allowed the diagnosis of numerous positive cases including carrier statuses, multiple infections and novel pathogen detections within the indigenous cattle population. Moreover, the RLB method here described enabled the detection of veterinary agents not only pertaining to bovine health, including also those of zoonotic importance. The high prevalence recorded for T. mutans, T. velifera, A. marginale, T. taurotragi and Anaplasma sp. (Omatjenne), suggests they may be endemically established in Nigeria, whereas the lower prevalence recorded for other microorganisms (i.e. A. centrale and B. bovis) highlights a less stable epidemiological scenario, requiring further investigations.

Tsetse flies are able to acquire mixed infections naturally or experimentally either simultaneously or sequentially. Traditionally, natural infection rates in tsetse flies are estimated by microscopic examination of different parts of the fly after dissection, together with the isolation of the parasite in vivo. However, until the advent of molecular techniques it was difficult to speciate trypanosomes infections and to quantify trypanosome numbers within tsetse flies. Although more expensive, qPCR allows the quantification of DNA and is less time consuming due to real time visualization and validation of the results. The current study evaluated the application of qPCR to quantify the infection load of tsetse flies with T. b. brucei and T. congolense savannah and to study the possibility of competition between the two species. The results revealed that the two qPCR reactions are of acceptable efficiency (99.1% and 95.6%, respectively), sensitivity and specificity and can be used for quantification of infection load with trypanosomes in experimentally infected Glossina morsitans morsitans. The mixed infection of laboratory Glossina species and quantification of the infection suggests the possibility that a form of competition exists between the isolates of T. b. brucei and T. congolense savannah that we used when they co-exist in the fly midgut.