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1.
Ticks Tick Borne Dis ; 14(6): 102232, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37531888

RESUMO

Ticks are leading vectors of economically important pathogens that affect small ruminants due to favourable climatic conditions across different regions of the African continent. They are responsible for both direct and indirect economic losses in the livestock industry. This review focuses on the species diversity of hard ticks, their biology, tick-borne diseases of sheep and goats including non-infectious disease, and risk factors to tick infestation in Africa. Furthermore, our review provides recent updates on distribution of ticks and tick-borne pathogens of small ruminants in Africa. It was observed that several species and subspecies of hard ticks belonging to the genera Hyalomma (Hy), Rhipicephalus (Rh), Ixodes (I) and Amblyomma (Am) were found infesting small ruminants across the different regions of the continent. Of these genera, Rhipicephalus ticks accounts for the majority of the registered species, with exactly 27 different species infesting small ruminant stocks comprising of different developmental instars and adults of the tick. Rhipicephalus decolaratus, Rh. e. evertsi and Rh. appendiculatus were the three most common Rhipicephalus species reported. Both protozoal (Babesia and Theileria) and bacterial (Anaplasma, Rickettsia, Ehrlichia, Coxiella and Mycoplasma) pathogens have being reported to be amplified in several hard tick species and/or small ruminant hosts. Furthermore, tick paralysis and lameness were non-infectious conditions attributed to tick infestations. Amblyomma hebraeum and Rh. glabroscutatum may cause lameness in goats, while Hy. rufipes is responsible for the same condition in Merino sheep. Host paralysis due to a neurotoxin released by female Rh. e. evertsi and I. rubicundus has been documented within the continent. We therefore advocate for the need of integrated control measures against tick-borne pathogens (TBPs) including their arthropod vectors, to be performed simultaneously to ease the burden of vector-borne diseases in small ruminant production.


Assuntos
Doenças das Cabras , Ixodidae , Rhipicephalus , Rickettsia , Doenças dos Ovinos , Infestações por Carrapato , Doenças Transmitidas por Carrapatos , Animais , Feminino , Ovinos , Ixodidae/microbiologia , Cabras , Coxeadura Animal , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária , Doenças Transmitidas por Carrapatos/microbiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/microbiologia , Ruminantes , Amblyomma , África/epidemiologia , Doenças das Cabras/epidemiologia , Doenças dos Ovinos/epidemiologia
2.
Prev Vet Med ; 217: 105969, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37406502

RESUMO

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.


Assuntos
Animais Selvagens , Doenças do Cão , Animais , Cães , Doenças do Cão/epidemiologia , Zâmbia/epidemiologia , Eutanásia Animal , Demografia
3.
Front Microbiol ; 14: 1296522, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38169897

RESUMO

Background: Systematic infrastructure and regulatory weaknesses over many decades, in communities struggling with animal African trypanosomiasis (AAT) would be expected to create an environment that would promote drug misuse and risk development of drug resistance. Here, we explore rural community practices of livestock keepers, livestock extension officers and drug shop attendants to determine whether appropriate practice was being followed in administration of trypanocides and other drugs. Methods: A questionnaire-based survey was undertaken in southwestern Uganda in 2022 involving 451 farmers who kept cattle, sheep or goats and 79 "professionals" who were either livestock extension officers or drug shop attendants. Results: Respondents reported using one or more type of trypanocidal drug on 80.1% of the 451 farms in the last 30 days. Diminazene aceturate was used on around three-quarters of farms, while isometamidium chloride was used on around one-fifth. Homidium bromide was used on less than 1% of farms. Cattle were significantly more likely to be treated with trypanocides than sheep or goats. On around two-thirds of farms, trypanocides were prepared and injected by farmers, with extension officers administering these drugs on most of the other third, especially on cattle farms. Almost all drugs were obtained from privately-owned drug shops. For treatment of AAT with trypanocides, prescription-only medicines were routinely used by farmers without professional supervision and in the absence of a definitive diagnosis. While a far greater proportion of professionals had a better education and had received training on the use of trypanocides than farmers, there was relatively little difference in their ability to use these drugs correctly. Farmers were more likely than professionals to use only DA to treat trypanosomiasis and were more likely to use antibiotics as well as trypanocidal drugs to treat the animal. Furthermore, they estimated, on average, that twice the recommended dose of either diminazene aceturate or isometamidium chloride was needed to treat a hypothetical 400 kg bovine. A minority of both farmers and professionals reported that they observed the recommended withdrawal times following injection of trypanocidal drugs and very few of either group knew the recommended withdrawal times for milk or meat. Only one in six farmers reported using the sanative pair (alternating use of diminazene aceturate and isometamidium chloride), to reduce the risk of drug resistant trypanosome strains emerging, while this approach was more widely used by professionals. Farmers reported using antibiotics more commonly than the professionals, especially in sheep and goats, raising concerns as to overuse and misuse of this critical class of drugs. In addition to using trypanocides, most farmers also reported using a topical veterinary pesticide for the control of ticks and tsetse. On average, farmers spent 12.2% of their income from livestock sales on trypanocides. Conclusion: This study highlights the complexity of issues involved in the fight against AAT using drug treatment. A multistakeholder campaign to increase awareness among farmers, drug shop attendants, and extension workers of the importance of adherence to recommended drug dosing, using the sanative pair and following recommended drug withdrawal guidance would promote best practice, reduce the risk of emergence of resistant strains of trypanosomes, and support enhanced food safety.

4.
Pathogens ; 11(10)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36297157

RESUMO

Background Human African trypanocide resistance (HATr) is a challenge for the eradication of Human African Trypansomiaisis (HAT) following the widespread emergence of increased monotherapy drug treatment failures against Trypanosoma brucei gambiense and T. b. rhodesiense that are associated with changes in pathogen receptors. Methods: Electronic searches of 12 databases and 3 Google search websites for human African trypanocide resistance were performed using a keyword search criterion applied to both laboratory and clinical studies. Fifty-one publications were identified and included in this study using the PRISMA checklist. Data were analyzed using RevMan and random effect sizes were computed for the statistics at the 95% confidence interval. Results: Pentamidine/melarsoprol/nifurtimox cross-resistance is associated with loss of the T. brucei adenosine transporter 1/purine 2 gene (TbAT1/P2), aquaglyceroporins (TbAQP) 2 and 3, followed by the high affinity pentamidine melarsoprol transporter (HAPT) 1. In addition, the loss of the amino acid transporter (AAT) 6 is associated with eflornithine resistance. Nifurtimox/eflornithine combination therapy resistance is associated with AAT6 and nitroreductase loss, and high resistance and parasite regrowth is responsible for treatment relapse. In clinical studies, the TbAT1 proportion of total random effects was 68% (95% CI: 38.0−91.6); I2 = 96.99% (95% CI: 94.6−98.3). Treatment failure rates were highest with melarsoprol followed by eflornithine at 41.49% (95% CI: 24.94−59.09) and 6.56% (3.06−11.25) respectively. HATr-resistant phenotypes used in most laboratory experiments demonstrated significantly higher pentamidine resistance than other trypanocides. Conclusion: The emergence of drug resistance across the spectrum of trypanocidal agents that are used to treat HAT is a major threat to the global WHO target to eliminate HAT by 2030. T. brucei strains were largely resistant to diamidines and the use of high trypanocide concentrations in clinical studies have proved fatal in humans. Studies to develop novel chemotherapeutical agents and identify alternative protein targets could help to reduce the emergence and spread of HATr.

5.
Trop Med Infect Dis ; 7(9)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36136616

RESUMO

BACKGROUND: African trypanocide resistance is an emerging public health emergency whose control requires a revisit on farmer's knowledge, attitudes, and practices in developing countries. African animal trypanocide resistance (AATr) is rife in an environment where drug use and policy decisions are disjointed. The objective of the study was to identify community factors responsible for the development of AATr. This was important since diminazene aceturate (DA), isometamidium chloride (ISM), and homidium bromide (HB) have existed for over 30 years and no new drugs have been provided to farmers. METHODS: An electronic keyword search across 12 databases was conducted using a search criterion from 1806 to June 2022. This generated a total of 24 publications, but after removing duplicates, review articles, and nonrelated articles, a total of eight papers were included in the analysis by following the PRISMA checklist. A meta-analysis was conducted on the data extracted and the risk ratio and inverse variance at 95% confidence interval were calculated using RevMan®. RESULTS: All the eight articles in the study showed that DA was the most preferred trypanocide in both West and Eastern Africa. Poor farmer knowledge of AATr and limited drug options were major drivers for trypanocide resistance. In addition, farmer treatments, use of untrained personnel, poor administration, poor dosing, and preparation of trypanocides were major drivers for the development of AATr and similarities were identified in DA and ISM practices (P = 0.13). CONCLUSIONS: AATr is spread in developing countries due to a lack of community knowledge, attitudes, and drug-use practices. This situation could be reversed through interdisciplinary collaborations in endemic communities by promoting effective treatments and responsible drug handling.

6.
Vet Parasitol Reg Stud Reports ; 33: 100753, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35820726

RESUMO

Tick-borne pathogens (TBPs) pose an increased health and productivity risk to livestock in sub-Saharan Africa. Information regarding TBPs infecting small ruminants in Kano metropolis is scarce. Therefore, we investigated the molecular epidemiology of tick-borne pathogens of economic importance from sheep and goats in Kano, Nigeria using Polymerase chain reaction (PCR). A total of 346 blood DNA samples were collected from small ruminants and analyzed for TBPs using PCR and sequencing. Risk of infection was determined for age, sex, breed and animal species. Our results indicate the absence of piroplasmids (Babesia/Theileria) and Rickettsia spp. infections. The overall prevalence for Anaplasma spp. was 9.25% (32/346) with a higher prevalence in goats 13.59% (25/184) compared with sheep 4.32% (7/162). With respect to age of animals, goats >4 years had the highest prevalence of 32.45% (11/37) which differs significantly (P = 0.0059) compared with other age categories. Cross breed goats had a prevalence of 15.63% (5/32) compared with Kano brown breed 14.08 (20/142). Sex significant difference (P = 0.029) was observed in the goats with females having the highest prevalence 20.89% (14/67) compared with males 9.40% (11/117). Furthermore, with regards to sheep, no significant difference (P > 0.05) was observed with respect to age and breed. Finally, no significant difference (P > 0.05) was observed with the prevalence of Anaplasma spp. due to Body condition score (BCS) in both sheep and goats. Conclusively, the occurrence of TBPs in small ruminants is low. Continuous efforts in tick control must be sustained to ensure high productive yield and reduced disease burden associated with TBPs of sheep and goats in Kano metropolis.


Assuntos
Doenças das Cabras , Infecções por Rickettsia , Theileria , Carrapatos , Anaplasma/genética , Animais , Feminino , Doenças das Cabras/epidemiologia , Cabras/microbiologia , Masculino , Nigéria/epidemiologia , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/veterinária , Fatores de Risco , Ruminantes , Ovinos , Theileria/genética , Carrapatos/microbiologia
7.
Front Vet Sci ; 9: 828111, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356785

RESUMO

African trypanosomiasis is associated with Trypanosoma evansi, T. vivax, T. congolense, and T. brucei pathogens in African animal trypanosomiasis (AAT) while T. b gambiense and T. b rhodesiense are responsible for chronic and acute human African trypanosomiasis (HAT), respectively. Suramin sodium suppresses ATP generation during the glycolytic pathway and is ineffective against T. vivax and T. congolense infections. Resistance to suramin is associated with pathogen altered transport proteins. Melarsoprol binds irreversibly with pyruvate kinase protein sulfhydryl groups and neutralizes enzymes which interrupts the trypanosome ATP generation. Melarsoprol resistance is associated with the adenine-adenosine transporter, P2, due to point mutations within this transporter. Eflornithine is used in combination with nifurtimox. Resistance to eflornithine is caused by the deletion or mutation of TbAAT6 gene which encodes the transmembrane amino acid transporter that delivers eflornithine into the cell, thus loss of transporter protein results in eflornithine resistance. Nifurtimox alone is regarded as a poor trypanocide, however, it is effective in melarsoprol-resistant gHAT patients. Resistance is associated with loss of a single copy of the genes encoding for nitroreductase enzymes. Fexinidazole is recommended for first-stage and non-severe second-stage illnesses in gHAT and resistance is associated with trypanosome bacterial nitroreductases which reduce fexinidazole. In AAT, quinapyramine sulfate interferes with DNA synthesis and suppression of cytoplasmic ribosomal activity in the mitochondria. Quinapyramine sulfate resistance is due to variations in the potential of the parasite's mitochondrial membrane. Pentamidines create cross-links between two adenines at 4-5 pairs apart in adenine-thymine-rich portions of Trypanosoma DNA. It also suppresses type II topoisomerase in the mitochondria of Trypanosoma parasites. Pentamidine resistance is due to loss of mitochondria transport proteins P2 and HAPT1. Diamidines are most effective against Trypanosome brucei group and act via the P2/TbAT1 transporters. Diminazene aceturate resistance is due to mutations that alter the activity of P2, TeDR40 (T. b. evansi). Isometamidium chloride is primarily employed in the early stages of trypanosomiasis and resistance is associated with diminazene resistance. Phenanthridine (homidium bromide, also known as ethidium bromide) acts by a breakdown of the kinetoplast network and homidium resistance is comparable to isometamidium. In humans, the development of resistance and adverse side effects against monotherapies has led to the adoption of nifurtimox-eflornithine combination therapy. Current efforts to develop new prodrug combinations of nifurtimox and eflornithine and nitroimidazole fexinidazole as well as benzoxaborole SCYX-7158 (AN5568) for HAT are in progress while little comparable progress has been done for the development of novel therapies to address trypanocide resistance in AAT.

8.
Front Vet Sci ; 9: 950248, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36686196

RESUMO

Background: African animal trypanocide resistance (AATr) continues to undermine global efforts to eliminate the transmission of African trypanosomiasis in endemic communities. The continued lack of new trypanocides has precipitated drug misuse and overuse, thus contributing to the development of the AATr phenotype. In this study, we investigated the threat associated with AATr by using the major globally available chemotherapeutical agents. Methods: A total of seven electronic databases were screened for an article on trypanocide resistance in AATr by using keywords on preclinical and clinical trials with the number of animals with treatment relapse, days taken to relapse, and resistant gene markers using the PRISMA checklist. Data were cleaned using the SR deduplicator and covidence and analyzed using Cochrane RevMan®. Dichotomous outputs were presented using risk ratio (RR), while continuous data were presented using the standardized mean difference (SMD) at a 95% confidence interval. Results: A total of eight publications in which diminazene aceturate (DA), isometamidium chloride (ISM), and homidium chloride/bromide (HB) were identified as the major trypanocides were used. In all preclinical studies, the development of resistance was in the order of HB > ISM > DA. DA vs. ISM (SMD = 0.15, 95% CI: -0.54, 0.83; I 2 = 46%, P = 0.05), DA vs. HB (SMD = 0.96, 95% CI: 0.47, 1.45; I 2 = 0%, P = 0.86), and HB vs. ISM (SMD = -0.41, 95% CI: -0.96, 0.14; I 2 = 5%, P = 0.38) showed multiple cross-resistance. Clinical studies also showed evidence of multi-drug resistance on DA and ISM (RR = 1.01, 95% CI: 0.71-1.43; I 2 = 46%, P = 0.16). To address resistance, most preclinical studies increased the dosage and the treatment time, and this failed to improve the patient's prognosis. Major markers of resistance explored include TbAT1, P1/P2 transporters, folate transporters, such as F-I, F-II, F-III, and polyamine biosynthesis inhibitors. In addition, immunosuppressed hosts favor the development of AATr. Conclusion: AATr is a threat that requires a shift in the current disease control strategies in most developing nations due to inter-species transmission. Multi-drug cross-resistance against the only accessible trypanocides is a major public health risk, justifying the need to revise the policy in developing countries to promote control of African trypanosomiasis.

9.
Front Public Health ; 9: 590458, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956994

RESUMO

Background: Low-income earners are particularly vulnerable to mental health, consequence of the coronavirus disease 2019 (COVID-19) lockdown restrictions, due to a temporary or permanent loss of income and livelihood, coupled with government-enforced measures of social distancing. This study evaluates the mental health status among low-income earners in southwestern Uganda during the first total COVID-19 lockdown in Uganda. Methods: A cross-sectional descriptive study was undertaken amongst earners whose income falls below the poverty threshold. Two hundred and fifty-three (n = 253) male and female low-income earners between the ages of 18 and 60 years of age were recruited to the study. Modified generalized anxiety disorder (GAD-7), Spielberger's State-Trait Anger Expression Inventory-2 (STAXI-2), and Beck Depression Inventory (BDI) tools as appropriate were used to assess anxiety, anger, and depression respectively among our respondents. Results: Severe anxiety (68.8%) followed by moderate depression (60.5%) and moderate anger (56.9%) were the most common mental health challenges experienced by low-income earners in Bushenyi district. Awareness of mental healthcare increased with the age of respondents in both males and females. A linear relationship was observed with age and depression (r = 0.154, P = 0.014) while positive correlations were observed between anxiety and anger (r = 0.254, P < 0.001); anxiety and depression (r = 0.153, P = 0.015) and anger and depression (r = 0.153, P = 0.015). Conclusion: The study shows the importance of mental health awareness in low resource settings during the current COVID-19 pandemic. Females were identified as persons at risk to mental depression, while anger was highest amongst young males.


Assuntos
COVID-19 , Pandemias , Adolescente , Adulto , Ira , Ansiedade/epidemiologia , Transtornos de Ansiedade/epidemiologia , Controle de Doenças Transmissíveis , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pobreza , SARS-CoV-2 , Uganda/epidemiologia , Adulto Jovem
10.
Am J Trop Med Hyg ; 105(6): 1582-1589, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34491218

RESUMO

Elimination of dog-transmitted human rabies worldwide will require large-scale dog vaccination campaigns. However, this places participating vaccinators at increased risk. Data from the 2016-2017 Haitian mass rabies vaccination campaign was analyzed to determine dog bite incidence among vaccinators. A survey was then developed for completion by all identifiable bitten vaccinators covering demographics; experience and training; bite episode details; attitudes toward dogs and rabies; and medical care. A parallel group of unbitten vaccinators was also surveyed. Dog bite incidence was 0.03% (43/127,000) of all dogs vaccinated. The capture, vaccinate, and release method of vaccination carried a significantly higher risk of dog bite (0.35%, 6/1,739 vaccinations) than other methods (P < 0.001). Twenty-seven bitten vaccinators, and 54 control vaccinators were included in the survey analysis. No differences were found between groups in demographics, experience, or training. However, bitten vaccinators were significantly more likely than the control group to have experienced a dog bite before the study period (P < 0.001). This may be associated with a lesser appreciation of dogs, and/or a poorer ability to interpret dog behavioral signals within this group. Although 98% of the control group indicated they would seek medical care for a dog bite, only 35% of bitten vaccinators sought such care. On a yearly basis, for the Haitian campaign, a full series of postexposure rabies vaccinations for all bite victims would prove more cost-effective than preexposure vaccination of all vaccinators. These findings may prove useful for the planning and safety of future mass dog vaccination campaigns.


Assuntos
Técnicos em Manejo de Animais , Mordeduras e Picadas/epidemiologia , Doenças do Cão/prevenção & controle , Vacinação em Massa , Raiva/veterinária , Médicos Veterinários , Adulto , Idoso , Animais , Cães , Feminino , Haiti/epidemiologia , Humanos , Programas de Imunização , Incidência , Masculino , Pessoa de Meia-Idade , Raiva/prevenção & controle , Vacina Antirrábica/uso terapêutico , Inquéritos e Questionários , Adulto Jovem
11.
Front Vet Sci ; 8: 611141, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381829

RESUMO

Background: Tsetse-transmitted human African trypanosomiasis (HAT) remains endemic in Uganda. The chronic form caused by Trypanosoma brucei gambiense (gHAT) is found in north-western Uganda, whereas the acute zoonotic form of the disease, caused by T. b. brucei rhodesiense (rHAT), occurs in the eastern region. Cattle is the major reservoir of rHAT in Uganda. These two forms of HAT are likely to converge resulting in a public health disaster. This study examines the intricate and intrinsic links between cattle herd dynamics, livestock trade and potential risk of spread of rHAT northwards. Methods: A bio-economic cattle herd model was developed to simulate herd dynamics at the farm level. Semi-structured interviews (n = 310), focus group discussions (n = 9) and key informant interviews (n = 9) were used to evaluate livestock markets (n = 9) as part of the cattle supply chain analysis. The cattle market data was used for stochastic risk analysis. Results: Cattle trade in eastern and northern Uganda is dominated by sale of draft and adult male cattle as well as exportation of young male cattle. The study found that the need to import draft cattle at the farm level was to cover deficits because of the herd structure, which is mostly geared towards animal traction. The importation and exportation of draft cattle and disposal of old adult male cattle formed the major basis of livestock movement and could result in the spread of rHAT northwards. The risk of rHAT infected cattle being introduced to northern Uganda from the eastern region via cattle trade was found to be high (i.e. probability of 1). Conclusion: Through deterministic and stochastic modelling of cattle herd and cattle trade dynamics, this study identifies critical links between livestock production and trade as well as potential risk of rHAT spread in eastern and northern Uganda. The findings highlight the need for targeted and routine surveillance and control of zoonotic diseases such as rHAT.

12.
Front Vet Sci ; 8: 611132, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262958

RESUMO

Background: Infected cattle sourced from districts with established foci for Trypanosoma brucei rhodesiense human African trypanosomiasis (rHAT) migrating to previously unaffected districts, have resulted in a significant expansion of the disease in Uganda. This study explores livestock movement data to describe cattle trade network topology and assess the effects of disease control interventions on the transmission of rHAT infectiousness. Methods: Network analysis was used to generate a cattle trade network with livestock data which was collected from cattle traders (n = 197) and validated using random graph methods. Additionally, the cattle trade network was combined with a susceptible, infected, recovered (SIR) compartmental model to simulate spread of rHAT (R o 1.287), hence regarded as "slow" pathogen, and evaluate the effects of disease interventions. Results: The cattle trade network exhibited a low clustering coefficient (0.5) with most cattle markets being weakly connected and a few being highly connected. Also, analysis of the cattle movement data revealed a core group comprising of cattle markets from both eastern (rHAT endemic) and northwest regions (rHAT unaffected area). Presence of a core group may result in rHAT spread to unaffected districts and occurrence of super spreader cattle market or markets in case of an outbreak. The key cattle markets that may be targeted for routine rHAT surveillance and control included Namutumba, Soroti, and Molo, all of which were in southeast Uganda. Using effective trypanosomiasis such as integrated cattle injection with trypanocides and spraying can sufficiently slow the spread of rHAT in the network. Conclusion: Cattle trade network analysis indicated a pathway along which T. b. rhodesiense could spread northward from eastern Uganda. Targeted T. b. rhodesiense surveillance and control in eastern Uganda, through enhanced public-private partnerships, would serve to limit its spread.

14.
Vaccines (Basel) ; 9(3)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809269

RESUMO

Background-misinformation and mistrust often undermines community vaccine uptake, yet information in rural communities, especially of developing countries, is scarce. This study aimed to identify major challenges associated with coronavirus disease 2019 (COVID-19) vaccine clinical trials among healthcare workers and staff in Uganda. Methods-a rapid exploratory survey was conducted over 5 weeks among 260 respondents (66% male) from healthcare centers across the country using an online questionnaire. Twenty-seven questions assessed knowledge, confidence, and trust scores on COVID-19 vaccine clinical trials from participants in 46 districts in Uganda. Results-we found low levels of knowledge (i.e., confusing COVID-19 with Ebola) with males being more informed than females (OR = 1.5, 95% CI: 0.7-3.0), and mistrust associated with policy decisions to promote herbal treatments in Uganda and the rushed international clinical trials, highlighting challenges for the upcoming Oxford-AstraZeneca vaccinations. Knowledge, confidence and trust scores were higher among the least educated (certificate vs. bachelor degree holders). We also found a high level of skepticism and possible community resistance to DNA recombinant vaccines, such as the Oxford-AstraZeneca vaccine. Preference for herbal treatments (38/260; 14.6%, 95% CI: 10.7-19.3) currently being promoted by the Ugandan government raises major policy concerns. High fear and mistrust for COVID-19 vaccine clinical trials was more common among wealthier participants and more affluent regions of the country. Conclusion-our study found that knowledge, confidence, and trust in COVID-19 vaccines was low among healthcare workers in Uganda, especially those with higher wealth and educational status. There is a need to increase transparency and inclusive participation to address these issues before new trials of COVID-19 vaccines are initiated.

15.
Front Vet Sci ; 8: 616865, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33829051

RESUMO

Background: The endemic vector-borne diseases transmitted by tsetse and ticks impose heavy burdens on the livestock keepers in Africa. Applying deltamethrin to the belly, legs, and ears of cattle offers a possibility of mitigating these losses at a cost affordable to livestock keepers. Although studies have quantified the impacts of individual diseases on livestock productivity, little is known about the dual economic benefits of controlling both tsetse and ticks, nor about the number of cattle that need to be treated to confer these benefits. Alongside an epidemiological study in south-east Uganda, a farm level assessment was done to investigate the benefits and costs of spraying different proportions of the village cattle population using this restricted application protocol. Methods: A study comprising 1,902 semi-structured interviews was undertaken over a period of 18 months. Financial data on household income and expenditure on cattle was collected, and cost-benefit analysis was done pre- and post-intervention and for different spraying regimes. The total cost of the intervention was obtained from the implementation costs of the epidemiological study and from expenses incurred by participating farmers enabling examination of benefit-cost ratios and incremental benefit-cost ratios for each treatment regime. Results: The benefit-cost analysis of spraying 25%, 50%, and 75% of the cattle population yielded average benefit-cost ratios of 3.85, 4.51, and 4.46. The incremental benefit-cost ratios from spraying each additional 25% of the cattle population were 11.38, 3.89, and 0.79, showing a very high return on investment for spraying 50% of the population, with returns reducing thereafter. Conclusion: Comparing the gross margins per bovine, the study found that increasing the proportion of cattle sprayed yielded increasing benefits to the farmers, but that these benefits were subject to diminishing returns. From a practical viewpoint, this study recommends spraying only draft cattle to control trypanosomiasis and tick-borne diseases in this area as they make 38.62% of the cattle population, approaching the 50% threshold. In areas with a lower proportion of draft males, farmers could be advised to also include cows.

16.
BMC Vet Res ; 17(1): 95, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648507

RESUMO

BACKGROUND: Brucellosis is a contagious zoonotic disease of great public health and economic significance especially in developing countries. The disease affects humans and several species of livestock and wildlife. Studies on Brucellosis in wildlife in Uganda have been limited to single populations particularly in Queen Elizabeth National Park. This study aimed at estimating the percentage of positive samples of Brucella spp. in wildlife in four major national parks of Uganda. This was a retrospective survey which utilized archived samples collected from wildlife during the annual disease surveillance activities between 2013 and 2017. RESULTS: A total of 241 samples from seven species namely African buffalo (Syncerus caffer, n = 109), African elephant (Loxodonta africana, n = 22), giraffe (Giraffa camelopardalis rothschildi, n = 41), Uganda kob (Kobus kob thomasi, n = 36), lion (Panthera leo, n = 6), plain zebra (Equus quagga, n = 25), and bushbuck (Tragelaphus scriptus, n = 2), were tested for antibodies using the Rose Bengal Plate Test. The overall percentage of positive samples in the four national parks was 31.1% (75/241; 95% CI: 25.6-37.2). Kidepo Valley National Park had a significantly higher percentage of positive samples of 55.9% (19/34; 95% CI: 39.5-71.1) compared to other sampled national parks (p < 0.05). Lions had significantly higher percentage of positive samples at 66.7% (4/6) than African buffalo at 48.6% (53/109, p < 0.0001). There were no antibodies for Brucella spp. detected in African elephant and bushbuck. CONCLUSION: This study shows variations in percentage of positive samples with Brucella spp. between species and across national parks and notably a high percentage with Brucella spp. in wildlife in Uganda than that recorded elsewhere in sub-Saharan region of Africa. Potential for transmission to other wildlife and spill over to livestock is high especially in national parks with high livestock-wildlife interaction.


Assuntos
Animais Selvagens/microbiologia , Brucella/imunologia , Brucelose/veterinária , Animais , Anticorpos Antibacterianos/sangue , Brucelose/epidemiologia , Parques Recreativos , Estudos Retrospectivos , Estudos Soroepidemiológicos , Uganda/epidemiologia
17.
Heliyon ; 7(1): e05688, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33437885

RESUMO

BACKGROUND: Information as regards the epidemiology of the Anaplasmataceae in small ruminants in several low- and middle-income countries is scarce. METHODS: In this study a total of 712 DNA samples collected from small ruminants were analyzed for Anaplasmataceae and Anaplasma ovis using the 16S rRNA and MSP4 genes respectively. Infection risk was assessed by location, sex and age of the animals and qGIS® was used to construct spatial maps. RESULTS: The prevalence of Anaplasmataceae spp was 89.1% (95% CI: 77.5-95.9) and 79.1% (95% CI: 75.9-82.1) in ovines and caprines respectively (RR = 1.1, 95% CI: 1.0-1.3); higher than those previously reported in other eastern African countries. The prevalence of A. ovis was 26.1% and 25.4% for both ovines and caprines respectively with ovines showing significantly higher levels of infection than caprines (P < 0.05). The risk of Anaplasma ovis infections was not affected by age (OR = 1.2, 95% CI: 0.9-1.7) or sex (OR = 1.1, 95% CI: 0.6-2.0). Small ruminants located at the forest edge (<0.3 km) showed higher A. ovis prevalence than those found inland with infections present in the midland regions associated with increased agricultural activity. CONCLUSION: Anaplasma ovis remains a major challenge for small ruminant husbandry in Uganda and infections are under-reported. Policy efforts to prioritize management of Anaplasmataceae for small ruminant health would promote livestock productivity in vulnerable communities, improving livelihoods and ecosystem health.

18.
Acta Parasitol ; 66(1): 116-128, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32780296

RESUMO

INTRODUCTION: Glossina spp. (Glossinidae), Tabanus spp. (Tabanidae), Ancala spp. (Tabanidae), Atylotus spp. (Tabanidae) and Stomoxys spp. (Muscidae) are important transmitting vectors of African animal trypanosomosis in sub-Saharan Africa. There is paucity of information on the distribution and identification of these flies in cattle settlements in southwest Nigeria. METHODS: The distribution patterns, genetic variations and diversities of dipteran flies in southwest Nigeria were described and identified using morphological and molecular analysis of the 28S rDNA gene. RESULTS: Of the 13,895 flies examined morphologically between April 2016 and March 2017, tabanids were identified [Tabanus (0.34%), Ancala (0.03%), Atylotus (0.01%), Haematopota (0.014%) and Chrysops (0.11%)]. Two stomoxyine species were identified; Stomoxys niger niger Macquart (45.30%) and Stomoxys calcitrans Linnaeus (17.29%) and two Glossina spp. namely; Glossina p. gambiense Vanderplank, 1911 (0.46%) and Glossina tachinoides Westwood (0.51%) were identified. The identities were further confirmed in a BLAST search using their nucleotide sequences. The median-joining network of the 28S rDNA gene sequences indicated that fly species examined were genetically distinct. The apparent density of all the trapped flies was highest at a mean temperature of 26-28 â„ƒ, humidity > 80% and rainfall of 150-220 mm/month. The distribution of flies was observed to increase as vegetation increased in density and decreased in areas with relatively high human population density (> 100/km2). CONCLUSIONS: The population indices of the 28S rDNA gene of the flies suggest that analysis of nuclear DNA fragments may provide more information on the molecular ecology of these flies. Characterising fly species and assessing their impact are essential in distribution and monitoring AAT spread.


Assuntos
Dípteros , Trypanosoma , Tripanossomíase Africana , Moscas Tsé-Tsé , Animais , Bovinos , Humanos , Nigéria , Trypanosoma/genética
19.
PLoS One ; 15(11): e0242435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33216770

RESUMO

African animal trypanosomosis (AAT) is transmitted cyclically by tsetse flies and mechanically by biting flies (tabanids and stomoxyines) in West Africa. AAT caused by Trypanosoma congolense, T. vivax and T. brucei brucei is a major threat to the cattle industry. A mathematical model involving three vertebrate hosts (cattle, small ruminants and wildlife) and three vector flies (Tsetse flies, tabanids and stomoxyines) was described to identify elimination strategies. The basic reproduction number (R0) was obtained with respect to the growth rate of infected wildlife (reservoir hosts) present around the susceptible population using a next generation matrix technique. With the aid of suitable Lyapunov functions, stability analyses of disease-free and endemic equilibria were established. Simulation of the predictive model was presented by solving the system of ordinary differential equations to explore the behaviour of the model. An operational area in southwest Nigeria was simulated using generated pertinent data. The R0 < 1 in the formulated model indicates the elimination of AAT. The comprehensive use of insecticide treated targets and insecticide treated cattle (ITT/ITC) affected the feeding tsetse and other biting flies resulting in R0 < 1. The insecticide type, application timing and method, expertise and environmental conditions could affect the model stability. In areas with abundant biting flies and no tsetse flies, T. vivax showed R0 > 1 when infected wildlife hosts were present. High tsetse populations revealed R0 <1 for T. vivax when ITT and ITC were administered, either individually or together. Elimination of the transmitting vectors of AAT could cost a total of US$ 1,056,990 in southwest Nigeria. Hence, AAT in West Africa can only be controlled by strategically applying insecticides targeting all transmitting vectors, appropriate use of trypanocides, and institutionalising an appropriate barrier between the domestic and sylvatic areas.


Assuntos
Doenças dos Bovinos/prevenção & controle , Insetos Vetores/parasitologia , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/veterinária , Tripanossomíase Bovina/epidemiologia , Moscas Tsé-Tsé/parasitologia , África Ocidental/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Reservatórios de Doenças/parasitologia , Reservatórios de Doenças/veterinária , Inseticidas/farmacologia , Modelos Teóricos , Nigéria/epidemiologia , Tripanossomicidas/farmacologia , Trypanosoma congolense , Tripanossomíase Africana/prevenção & controle , Tripanossomíase Africana/transmissão , Tripanossomíase Bovina/prevenção & controle
20.
Front Public Health ; 8: 416, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850606

RESUMO

Background: Transmission of COVID-19 in developing countries is expected to surpass that in developed countries; however, information on community perceptions of this new disease is scarce. The aim of the study was to identify possible misconceptions among males and females toward COVID-19 in Uganda using a rapid online survey distributed via social media. Methods: A cross-sectional survey carried out in early April 2020 was conducted with 161 Ugandans, who purposively participated in the online questionnaire that assessed understandings of COVID-19 risk and infection. Sixty-four percent of respondents were male and 36% were female. Results: We found significant divergences of opinion on gendered susceptibility to COVID-19. Most female respondents considered infection risk, symptoms, severe signs, and death to be equally distributed between genders. In contrast, male respondents believed they were more at risk of infection, severe symptoms, severe signs, and death (52.7 vs. 30.6%, RR = 1.79, 95% CI: 1.14-2.8). Most women did not share this perception and disagreed that males were at higher risk of infection (by a factor of three), symptoms (79% disagree), severe signs (71%, disagree), and death (70.2% disagree). Overall, most respondents considered children less vulnerable (OR = 1.12, 95% CI: 0.55-2.2) to COVID-19 than adults, that children present with less symptoms (OR = 1.57, 95% CI: 0.77-3.19), and that there would be less mortality in children (OR = 0.92, 95% CI: 0.41-1.88). Of female respondents, 76.4% considered mortality from COVID-19 to be different between the young and the elderly (RR = 1.7, 95% CI: 1.01-2.92) and 92.7% believed young adults would show fewer signs than the elderly, and 71.4% agreed that elderly COVID-19 patients would show more severe signs than the young (OR = 2.2, 95% CI: 1.4, 4.8). While respondents considered that all races were susceptible to the signs and symptoms of infection as well as death from COVID-19, they considered mortality would be highest among white people from Europe and the USA. Some respondents (mostly male 33/102, 32.4%) considered COVID-19 to be a "disease of whites" (30.2%). Conclusion: The WHO has identified women and children in rural communities as vulnerable persons who should be given more attention in the COVID-19 national response programs across Africa; however, our study has found that men in Uganda perceive themselves to be at greater risk and that these contradictory perceptions (including the association of COVID-19 with "the white" race) suggest an important discrepancy in the communication of who is most vulnerable and why. Further research is urgently needed to validate and expand the results of this small exploratory study.


Assuntos
COVID-19/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Medição de Risco , Adolescente , Adulto , Estudos Transversais , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Uganda/epidemiologia , Adulto Jovem , Tratamento Farmacológico da COVID-19
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