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Article

Population Knowledge and Practices and the Prevalence of Trypanosomes Circulating in Domestic Animals in Three Active Human African Trypanosomiasis Foci in the Republic of Congo

by
Irina Bemba
1,2,*,
Arsene Lenga
1,
Herman Parfait Awono-Ambene
2 and
Christophe Antonio-Nkondjio
2,*
1
Laboratory of Animal Biology and Ecology, Faculty of Science and Technology, Marien Ngouabi University, Brazzaville B.P. 69, Congo
2
Institut de Recherche de Yaoundé (IRY), Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé B.P. 288, Cameroon
*
Authors to whom correspondence should be addressed.
Microbiol. Res. 2023, 14(3), 1067-1076; https://0-doi-org.brum.beds.ac.uk/10.3390/microbiolres14030071
Submission received: 21 February 2023 / Revised: 8 March 2023 / Accepted: 14 March 2023 / Published: 4 August 2023
(This article belongs to the Collection Public Health and Quality Aspects Related to Animal Productions)
Browse Figure
Review Reports Versions Notes

Abstract

:
Human African Trypanosomiasis (HAT) is still endemic in the Republic of Congo. Although the incidence of cases has significantly decreased over years, the disease still persists in some active foci. Factors contributing to the maintenance of the disease such as the existence of an animal reservoir or population knowledge are still not well known. It is in this context that a study focusing on the knowledge and practices of the population with regard to HAT as well as on the prevalence of trypanosomes infecting animals was undertaken in three active HAT foci in the Republic of Congo. The study was performed using field surveys conducted from November 2019 to June 2021. Domestic animal blood was examined by microscopy and PCR to detect the presence of trypanosomes. A structured questionnaire was administered to the population to assess their knowledge and practices concerning HAT in these endemic foci. More than half of the animals examined were found to be infected with trypanosomes (51.22%). The main trypanosome species infecting animals were Trypanosoma congolense savannah (67.2%) and Trypanosoma brucei (s.l.) (32.8%). No trypanosomes infecting humans were detected. Concerning household surveys, more than half of the respondents (52.9%) were fully aware of the mode of transmission and symptoms of the disease. The majority of people preferred to wear clothes covering the whole body and to use locally made soap as repellents to protect themselves from tsetse fly bites. This study suggests frequent circulation of animal trypanosomes in domestic animals and the use of personal measures to protect against tsetse fly bites. Updating information on the HAT animal reservoir and population knowledge alongside regular monitoring of the tsetse fly populations and the use of traps to control tsetse flies are crucial to drive efforts towards the elimination of gHAT in the Republic of Congo.

1. Introduction

Trypanosomiasis remains a major public health threat in sub-Saharan Africa. The disease, considered as a neglected tropical disease, is targeted by the World Health Organization (WHO) for elimination by 2030 as a public health problem [1]. Although tremendous efforts during the last decade enabled the reduction of the disease burden, it is still present in 20 countries in sub-Saharan Africa [1] and affects both humans and animals [2]. Trypanosomiasis caused by Trypanosoma brucei gambiense (gHAT) is widely distributed in West and Central Africa and accounts for 87% of reported sleeping sickness cases [1]. The populations most exposed to tsetse fly bites are rural populations engaged in agriculture, fishing, livestock rearing, or hunting activities [3,4]. The number of cases reported annually across the world is now below 2000 [5]. In order to reach the WHO’s target of zero HAT cases, factors that were not considered in the past should now be taken into account. This comprises the role of animals as reservoirs of gHAT [6,7,8] as well as the practices and attitudes of the populations living in endemic areas exposed to gHAT transmission. gHAT has long been considered as an anthropogenic disease, and control measures have mainly been directed toward the treatment of human cases and/or vector control [9]. Understanding the epidemiological role of animals as reservoirs in maintaining the transmission and resurgence of gHAT cases in active foci now requires further attention in order to drive efforts towards the elimination of the disease [9,10]. In the Republic of Congo, there have so far been few studies conducted on animal reservoirs [8,11,12,13]. Since the 1990s, no work has been carried out in this regard. This has led to significant gaps in knowledge on the prevalence of trypanosomes circulating in animals and the population’s knowledge, attitudes, and practices (KAP). Human behavior, population occupations or practices as well as cultural beliefs must be perfectly understood to avoid a possible recrudescence of the disease [14,15]. KAP studies on HAT in the DRC, South Sudan, and Uganda have highlighted the importance of understanding community attitudes and perceptions for effective engagement in HAT interventions [16,17,18]. Community education is therefore crucial to remove any misunderstandings that may constitute obstacles or potential barriers to control interventions or behavioral changes [19]. KAP surveys allow rapid assessment and constitute an inexpensive way to obtain a quick overview of key knowledge data [20]. In this regard, the present study was conducted with the objectives of identifying trypanosome species circulating in domestic animals and assessing the level of knowledge of the population on HAT in three selected endemic foci in the Republic of Congo.

2. Methodology

2.1. Study Sites

The study was conducted in three active HAT foci: Loudima, Mpouya, and Ngabé located in central and southern Congo.
Loudima (4°6′45″ S, 13°3′30″ E) is situated in the Bouenza division at about 300 km west of Brazzaville, the political capital of Congo. Mpouya (2°36′57″ S, 16°12′43″ E) is situated in the Plateaux division at about, 300 km north of Brazzaville. The site comprises several villages situated along the banks of the Congo River. Ngabé (3°12′52″ S, 16°10′1″ E) is situated in the Pool division, located about 200 km north of Brazzaville. It comprises several villages situated along the banks of the Congo River and facing the DRC. The inhabitants of these three foci live mainly from hunting, fishing, agriculture, and livestock. Livestock rearing is small-scale, comprising units of 10 to 50 domestic animals. The most common domestic animals in these foci are sheep, goats, and pigs. These are generally left free during the day and then kept in makeshift enclosures at night, made of stakes and wooden sleepers from the forest or shrubby savannah (Figure 1).

2.2. Ethical Considerations

The study received the approval of the Comité Ethique de la Recherche en Sciences de la Santé (CERSSA) with the registration number 206/MRSIT/IRSSA/CERSSA. The local administrative authorities as well as the owners of the animals also gave their verbal or written approval before the study was undertaken.

2.3. Livestock Surveys

Cross-sectional surveys were conducted in December 2019, November and December 2020, and June 2021. Domestic animals including cattle, pigs, donkeys, horses, goats, sheep, and goats were examined during field trips. Blood was collected from animals in villages where at least one case of HAT had been reported in the last 10 years. The different villages were selected according to the presence of domestic animals and biotopes favorable to tsetse fly and trypanosomiasis transmission. Before each survey, the objective of the study was explained to the inhabitants and local authorities of the different villages. The day before the sampling, residents who agreed to participate in the study were asked to keep the animals in their pens. With the cooperation of the owners, 5 mL of blood was collected from each animal by a veterinarian. Blood samples were collected from the jugular vein except for in the pigs, wherein they were collected from the subclavicular vein. Blood samples were collected in tubes containing EDTA and each tube was carefully labelled. Thick blood smears were also realized to detect trypanosomes.

2.4. Household Survey

Cross-sectional surveys were conducted in December 2019 and November and December 2020 in the three active foci. All heads of households who consented to participate were enrolled in the study. Interviews were conducted in French or translated in native or vernacular languages (lingala, téké or kituba) for those unable to understand French.
Information on participants’ practices and knowledge about HAT and the vector were captured using a structured questionnaire with open-ended and multiple-choice questions. Once the purpose of the study was explained to the participants, an interviewer accompanied by a local guide administered the questionnaire to the volunteers individually so as to avoid any influence on their responses. The terms ‘biyeko’, ‘keyi’, or ‘mokongi’ (referring to the tsetse fly in the different vernacular languages of these areas) were used and the questions rephrased if necessary to avoid any ambiguity. The questionnaire collected information on (i) socio-demographic characteristics of the respondent (age, sex, level of education, professional activity), (ii) knowledge, attitudes, and practices towards HAT (knowledge of the vector and symptoms, history of HAT cases, attitudes/practices of respondents towards bites and case management).
A classification of the population was performed to assess the level of knowledge of the population on the disease. People able to give at least three correct answers were considered to have appropriate knowledge of the disease (knowledge on transmission of HAT, knowledge of the vector, knowledge of symptoms). Those providing answers to less than three questions were considered to have poor knowledge.

2.5. DNA Extraction

DNA was extracted from the animals’ blood using the DNeasy Blood and Tissue Kit (Qiagen, Hilden, Germany) according to the manufacturer’s recommendations.

2.6. Molecular Identification of Different Trypanosome Species

For this identification, a nested PCR was performed by amplifying the internal transcribed spacer 1 (ITS1) of the ribosomal DNA of different trypanosome species, as described by Ravel et al. [21]. The first PCR was performed in a final volume of 25 μL containing 1 × PCR buffer (10 mM Tris-HCl (pH 9. 0), 50 mM KCl), 2 mM MgCl2, 1 μL (10 pmol) of each primer (5′-CAA ATT GCC CAA TGT CG-3′ and 5′-GCT GCG TTC AAC GAA-3′), 0.5 μL (200 mM) of dNTPs, 1 μL (one unit) of Taq DNA polymerase (5 U/μL), 5 μL of DNA, and 14 μL of nuclease-free water. The second was performed with the products of the first PCR diluted one-tenth, with two other different primers (5′-CCT GCA GCT GGA TCA T-3′ and 5′-ATC GCG ACA CGT TGT G-3′). The amplification program for both reactions was as follows: initial denaturation at 94 °C for 3 min and 30 s followed by 30 cycles at 94 °C for 30 s, 58 °C for 1 min, 72 °C for 1 min, and final elongation at 72 °C for 5 min. Trypanosome species were initially identified on the basis of the size of their ITS1 PCR products as estimated by agarose electrophoresis (2%).

2.7. Identification of Trypanosoma Congolense Forest and Trypanosoma Congolense Savannah

Following the amplification of ITS1 sequences, all samples between 600 and 650 bp in size corresponding to Trypanosoma congolense species were subjected to a further PCR where specific primers were used to identify Trypanosoma congolense forest and Trypanosoma congolence savannah. These identifications were carried out as described by Simo et al. [22] using primers TCF1/TCF2 for T. congolense forest type and TCS1/TCS2 for T. congolense savannah type.
The specific fragment of Trypanosoma congolense forest type was amplified according to the protocol described by Masiga et al. [23] This amplification was performed in 15 µL of reaction medium containing 1 × PCR buffer (Tris-HCl PH 9; 50 mM KCl), 1.5 mM MgCl2, 200 µM of each dNTP, 0.3 units of Taq DNA polymerase, 20 pmoles of each TCF1/TCF2 primer, and 3 µL of DNA extract from each sample. The amplification programme was as follows: initial denaturation at 94 °C for 3 min 30 s, followed by 40 cycles of amplification including, for each cycle, a denaturation step at 94 °C for 30 s, a hybridization step at 60 °C for one minute, and an elongation step at 72 °C for one minute. A final elongation was performed at 72 °C for 5 min.
The identification of Trypanosoma congolense savannah type was performed according to the method described by Moser et al. [24]. The composition of the reaction medium as well as the amplification programme were the same as for the identification of Trypanosoma congolense forest type except for the primers which differed (TCS1/TCS2).

2.8. Statistical Analysis

Infection rates of trypanosomes of the subgenus Trypanozoon and Trypanosoma brucei (s.l.) were compared between animal species and HAT foci. The chi-square test was used to compare infection rates between animal species and different HAT foci. The difference was considered significant if the p-value was less than 0.05. Odd ratios were used to assess the level of association between different parameters.

3. Results

3.1. Livestock Survey

A total of 244 animals including 2 donkeys (0.82%), 7 cattle (2.87%), 8 horses (3.28%), 17 goats (6.97%), 207 sheep (84.83%), and 3 pigs (1.23%) were screened in Ngabé, Loudima, and Mpouya. Of these, 130 (53.28%) were screened in Loudima, 69 (28.28%) in Ngabé, and 45 (18.44%) in Mpouya. Sheep were the most abundant and were frequently detected infected after microscopic and PCR analysis (Table 1).
After PCR analysis, 2 pigs (66.67%), 1 goat (5.88%) and 81 sheep (39.13%) were found infected with Trypanosoma congolense Savannah, whereas 1 goat (5.88%) and 40 sheep (19.32%) were found infected by T. brucei (s.l.). No significant difference in the infection rate was found between animals screened (χ2 = 0.14; p = 0.70).
A significant difference was detected between diagnostic methods; using microscopy, only 21 (8.6%) samples out of 244 were detected positive for trypanosomes whereas up to 125 (51.22%) samples were detected positive after PCR (χ2 = 11.526; p = 0.0007). No trypanosomes infecting humans were detected in the animals screened.

3.2. Human Survey Data

3.2.1. Socio-Demographics Characteristics of Participants

A total of 160 heads of household were interviewed during the survey (67 were from Loudima, 47 from Mpouya, and 46 from Ngabé). Men represented 61.87% and women 38.13% of people interviewed. The majority of heads of household interviewed had secondary education levels (67.5%, N = 108), 17.5%, (N = 28) had primary education levels, and 5% (N = 8) had university education levels. Farming was the main activity practiced by more than half of the interviewees (53.75%) (Table 2).

3.2.2. General Knowledge on HAT

The majority of respondents (59.37%) attributed the transmission of sleeping sickness to tsetse fly bites. When asked if they knew about the tsetse fly, 86.25% (N = 138) responded positively. However, of the 138 who claimed to know the vector, only 52.9% (N = 73) correctly identified the tsetse fly in the image. A large number of people reported knowing the symptoms of HAT (69.37%) and the most frequently cited symptom was drowsiness (73.9%). (Table 3).
Further assessment was conducted to determine the proportion of the population having good knowledge and those having poor knowledge of HAT. People able to give at least three correct answers were considered to have appropriate knowledge of the disease (knowledge on mode of transmission of HAT, knowledge of the vector, knowledge of symptoms). Those providing correct answers to less than three questions were considered to have poor knowledge. From the analysis, it appeared that proportion of people with good knowledge was high in Loudima followed by Mpouya and Ngabé (Table 4).

3.2.3. Risk of Bites by Tsetse Flies According to Different Factors

In all three sites, many heads of household interviewed complained of tsetse fly bites while conducting their business. The risk of being bitten by tsetse flies was similar no matter the primary occupation of the respondent (Table 5). Inhabitants of Ngabé were 1.53 times more likely to be bitten compared to those of Loudima. Yet, no significant difference in the risk of exposure to tsetse fly bites according to study sites was recorded.

3.2.4. HAT Case Management

Concerning case management, 98% of respondents (N = 157) reported taking their patient to the hospital and not to traditional healers (Table 6).

3.2.5. History of HAT in the Family

Of the 160 heads of household interviewed, more than half, precisely 35, responded to have had at least one case of HAT in the family (Table 7).

4. Discussion

The present study adds on to the body of data recorded so far on gHAT in the Republic of Congo [25,26]. It should be noted that since the 1990s there have been less than 10 studies on HAT carried out in Congo; as a consequence, there are large gaps in the knowledge on the evolution of HAT cases in active foci, vector distribution, transmission, i.e., either dynamic or animal reservoir, population knowledge, and practices. It is becoming crucial to update information on the HAT situation in the country [10,27,28]. One of the objectives of the present study was to determine the prevalence of trypanosomes and identify species infecting domestic animals in three of the most important HAT endemic foci in the Republic of Congo. More than half of the animals examined were found infected by trypanosomes. Both Trypanosoma congolense savannah and Trypanosoma brucei (s.l.) were detected in high frequencies, suggesting a high risk of animal trypanosomiasis in these foci. No gHAT was recorded, thus confirming the extremely low circulation of this species in the studied foci, as evidenced by a recent study [26]. Trypanosoma brucei (s.l.) and Trypanosoma congolense savannah have frequently been found in domestic animals in different countries [29,30]. Animal trypanosomiasis represents a fairly heavy burden on rural populations, as it requires the frequent use of trypanocides for animal treatment, which is not without cost [31]. Animals detected infected by trypanosome included goats, pigs, and sheep. Sheep were by far the most infected and were found infected by both Trypanosoma brucei (s.l.) and Trypanosoma congolense savannah. This could result from the fact that they were largely abundant in the area and probably less susceptible to trypanosomes infections. Our results are consistent with previous studies in different countries suggesting that domestic animals are also reservoirs of trypanosomes [27,30,32,33,34]. Although no gHAT case was detected, it is likely that domestic animals could serve as reservoirs for gHAT, being responsible for the occurrence of sporadic cases in dormant foci. The role of animals as reservoirs for gHAT should be taken into consideration when designing and implementing control strategies [35], particularly in countries targeting the elimination of HAT in the next decade, such as Congo.
In the Republic of Congo, there is a lack of data on population knowledge and practices towards HAT. Yet, such studies could be crucial to assess population adherence to control interventions [16,17,18]. The majority of respondents in the studied rural settings were farmers or fishers with basic educations. Similar population structures in HAT endemic foci have been reported in other sub-Saharan African countries [36,37,38]. More than half of the respondents knew the mode of transmission as well as the symptoms of the disease. These results are encouraging and similar to studies conducted in Zambia and Tanzania where participants were fully aware that tsetse fly bites transmit trypanosomiasis [39,40]. Concerning symptoms, the most cited was drowsiness followed by neurological disorders and fever. From the study, it appeared that the entire population irrespective of occupation was similarly exposed to tsetse fly bites. Other authors reported that farmers, hunters, and fishers were more exposed to tsetse fly bites than others [41,42]. Although people in the different study sites had main jobs, they also practiced agriculture, fishing, or hunting as additional activities which might have also exposed them to tsetse fly bites. Moreover, the fact that inhabitants of these villages regularly go to the river to fetch water or to buy fish or goods might have also exposed them to the bites of tsetse flies. HAT has been shown to affect people in close contact with waterways [43]. In terms of preventive measures, respondents were much more likely to opt to wear full-body clothing during their activities. Locally made repellents such as the soap munganga or Deko were also found to be used by the population to repel tsetse flies. The study also revealed that just under a quarter of the people interviewed said they had a family history of HAT cases. This information should be taken into account by control programmes when diagnosing patients, as it has been shown that people with a family history of HAT have a higher risk of contracting the disease than those without [43]. No trapping measures were found to be in place in the different foci, pointing to the need for complementing control interventions that should be implemented in the field to achieve HAT elimination in the Republic of Congo.

5. Conclusions

The present study provided updated information on the situation of HAT, particularly in terms of animal reservoirs and population knowledge and practices in three active foci in the Republic of Congo. Although gHAT was not detected, probably because of the low sample size of animals screened, more focus needs to be put on animals that could serve as reservoirs for HAT as the Republic of Congo is steadily approaching the elimination stage. More attention also needs to be paid to the population to make sure that they adhere to and support control strategies to successfully achieve elimination goals as soon as possible.

Author Contributions

Conceptualization, I.B. and C.A.-N.; methodology, I.B.; software, I.B. and C.A.-N.; validation, A.L., H.P.A.-A. and C.A.-N.; formal analysis, I.B.; investigation, I.B. and A.L.; data curation, I.B.; writing original draft preparation, I.B. and C.A.-N.; writing review and editing, A.L., H.P.A.-A. and C.A.-N.; supervision, A.L., H.P.A.-A. and C.A.-N.; funding acquisition, I.B. All authors have read and agreed to the published version of the manuscript.

Funding

This work received financial support from the OCEAC MTN KFW program. Ref CON_BEMBA. The funding body did not have any role in the design, collection of data, analysis and interpretation of data or in the drafting of the manuscript.

Institutional Review Board Statement

The animal study protocol was approved by the Comité Ethique de la Recherche en Sciences de la Santé (CERSSA) under number 206/MRSIT/IRSSA/CERSSA.

Informed Consent Statement

Informed consent statements were obtained from all participants involed in the study.

Data Availability Statement

The datasets supporting the findings of this paper are all included in this paper.

Acknowledgments

We gratefully acknowledge the financial support of the “Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC)”, the “Communauté Economique des Etats de l’Afrique Centrale (CEMAC)” and the German Federal Ministry for Economic Cooperation and Development (BMZ) through the German Development Bank (KfW). We are also grateful Nzoulani Albert, Louya Frederic and Kikoueri Anguerand for their work in the field, as well as to the inhabitants and administrative authorities of the villages of Mpouya, Ngabe and Loudima.

Conflicts of Interest

The authors declare no conflict of interest.

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Microbiolres 14 00071 g001
Figure 1. Map of Congo showing the different study sites (source: map made with ArcGIS V 10.5).
Figure 1. Map of Congo showing the different study sites (source: map made with ArcGIS V 10.5).
Microbiolres 14 00071 g001
Table 1. Trypanosome infections according to animal species and foci.
Table 1. Trypanosome infections according to animal species and foci.
FociAnimal ScreenedNMicroscopy ResultsPCR Results
Trypanosoma congolense savannahTrypanosoma brucei (s.l.)Trypanosoma congolense savannah-T. brucei (s.l.)
MpouyaDonkey20 (0%)0 (0%)0 (0%)0 (0%)
Cattle70 (0%)0 (0%)0 (0%)0 (0%)
Horse80 (0%)0 (0%)0 (0%)0 (0%)
Goat80 (0%)0 (0%)1 (12.5%)0 (0%)
Sheep200 (0%)0 (0%)16 (80%)0 (0%)
Total450 (0%)0 (0%)17 (37.77%)0 (0%)
NgabéGoat91 (11.11%)0 (0%)1 (11.11%)0 (0%)
Sheep600 (0%)2 (33.33%)18 (30%)1 (5%)
Total691 (1.45%)2 (33.33%)19 (27.54%)1 (4.76%)
LoudimaPig30 (0%)2 (33.33%)0 (0%)0 (0%)
Sheep12720 (15.75%)79 (62.2%)6 (4.72%)3 (3.53%)
Total13020 (15.38%)81 (62.31%)6 (4.62%)3 (2.31%)
Overall24421 (8.6%)83 (34.02%)42 (17.21%)4 (3.2%)
N: Number of animals examined.
Table 2. Socio-demographic characteristics of households interviewed in the three foci.
Table 2. Socio-demographic characteristics of households interviewed in the three foci.
MpouyaNgabé Loudima
ItemsCharacteristics N (%)N (%)N (%)Total
GenderMen34 (72.34)24 (52.17)41 (61.19)99 (61.87)
Women 13 (27.66)22 (47.83)26 (38.81)61 (38.13)
Highest level of education completedIlliterate2 (4.25)2 (4.35)12 (17.91)16 (10.00)
Primary level 3 (6.38)8 (17.39)17 (25.37)28 (17.5)
Secondary level36 (76.6)36 (78.26)36 (53.73)108 (67.5)
University level6 (12.77)0 (0.00)2 (2.99)8 (5.00)
OccupationFarmer12 (25.53)37 (80.44)37 (55.22)86 (53.75)
Small business10 (21.28)6 (13.04)20 (29.85)36 (22.5)
Retailer9 (19.15)3 (6.52)0 (0.00)12 (7.5)
Public servant16 (34.04)0 (0.00)10 (14.93)26 (16.25)
Table 3. Population knowledge of HAT and the use of preventive measures.
Table 3. Population knowledge of HAT and the use of preventive measures.
MpouyaNgabé Loudima
VariablesAnswersN (%)N (%)N (%)Total (%)
Knowledge of mode of transmission of HATTsetse fly bites26 (55.32)36 (78.26)44 (65.67)97 (60.63)
Mosquito bites5 (10.64)3 (6.52)5 (7.46)21 (13.12)
Midge bites 11 (23.4)2 (4.35)0 (0.00)14 (8.75)
Others3 (6.38)0 (0.00)1 (1.5)4 (2.5)
Do not know2 (4.26)5 (10.87)17 (25.37)24 (15)
Knowledge of vectorYes21 (60.00)12 (31.58)40 (61.54)73 (52.9)
No14 (40.00)26 (68.42)25 (38.46)65 (47.1)
Knowledge of symptoms Drowsiness19 (67.86)25 (60.98)37 (90.24)81 (73.9)
Behavioural disorders 7 (25.00)14 (34.14)1 (2.44)22 (19.8)
Others2 (7.14)2 (4.88)3 (7.32)7 (6.3)
Do not know19 (40.43)5 (10.87)26 (38.81)50 (30.63)
Preventive measuresUse of repellents (home-made soap: munganga or Deko)14 (48.28)3 (8.33)1 (2.13)18 (16.07)
Wearing long clothes8 (27.59)10 (27.78)7 (14.89)25 (22.32)
Using the broom1 (3.44)16 (44.45)4 (8.51)21 (18.75)
Avoiding watercourses0 (0.00)3 (8.33)4 (8.51)7 (6.25)
None6 (20.69)4 (11.11)31 (65.96)41 (36.61)
N: Number of people interviewed.
Table 4. Proportion of the population with good or poor knowledge of HAT.
Table 4. Proportion of the population with good or poor knowledge of HAT.
Knowledge
FociGoodPoorp-Value
Loudima22 (32.84%)45 (67.16%)
Mpouya14 (29.79%)33 (70.21%)0.180
Ngabé9 (19.57%)37 (80.43%)
Table 5. People frequently bitten by tsetse flies.
Table 5. People frequently bitten by tsetse flies.
ItemsCharacteristicsFrequently BittenNot BittenORp-Value
OccupationPublic servant19 (73.08)7 (26.92)1
Retailer8 (66.67)4 (33.33)0.73 (0.16–3.23)0.686
Small business27 (75)9 (25)1.10 (0.35–3.48)0.864
Farmer58 (67.44)28 (32.65)0.76 (0.28–2.02)0.587
FociLoudima47 (70.15)20 (29.85)1
Mpouya29 (61.7)18 (38.3)0.68 (0.31–1.50)0.347
Ngabé36 (78.26)10 (21.74)1.53 (0.63–3.67)0.339
OR: Odd ratio.
Table 6. Behavior of the population concerning HAT treatment.
Table 6. Behavior of the population concerning HAT treatment.
FactorsCharacteristics Hospital (%)Traditional Medicine (%)
Level of educationIlleterate16 (100%)0 (0.00%)
Primary level 28 (100%)0 (0.00%)
Secondary level105 (97.22%)3 (2.78%)
University level8 (100%)0 (0.00%)
OccupationFarmer85 (98.84%)1 (1.16%)
Small business35 (97.22%)1 (2.78%)
Retailer11 (91.67%)1 (8.33%)
Public servant26 (100%)0 (0.00%)
FociLoudima67 (100%)0 (0.00%)
Mpouya46 (97.87%)1 (2.13%)
Ngabé44 (95.65%)2 (4.35%)
HAT caseRecent case15 (100%)0 (0.00%)
Old case17 (85%)3 (15%)
GenderMen97 (97.98%)2 (2.02%)
Women60 (98.36%)1 (1.64%)
Table 7. History of HAT cases in the family.
Table 7. History of HAT cases in the family.
FociNumber of Families InterviewedOlder Cases of HAT (Over 10 Years)Recent Cases of HAT (Last 10 Years)No Cases
Ngabé467 (15.2%)4 (8.7%)35 (76.1%)
Mpouya 475 (10.64%)4 (8.51%)38 (80.85%)
Loudima678 (11.94%)7 (10.45%)52 (77.61%)
Total16020 (12.5%)15 (9.37%)
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Bemba, I.; Lenga, A.; Awono-Ambene, H.P.; Antonio-Nkondjio, C. Population Knowledge and Practices and the Prevalence of Trypanosomes Circulating in Domestic Animals in Three Active Human African Trypanosomiasis Foci in the Republic of Congo. Microbiol. Res. 2023, 14, 1067-1076. https://0-doi-org.brum.beds.ac.uk/10.3390/microbiolres14030071

AMA Style

Bemba I, Lenga A, Awono-Ambene HP, Antonio-Nkondjio C. Population Knowledge and Practices and the Prevalence of Trypanosomes Circulating in Domestic Animals in Three Active Human African Trypanosomiasis Foci in the Republic of Congo. Microbiology Research. 2023; 14(3):1067-1076. https://0-doi-org.brum.beds.ac.uk/10.3390/microbiolres14030071

Chicago/Turabian Style

Bemba, Irina, Arsene Lenga, Herman Parfait Awono-Ambene, and Christophe Antonio-Nkondjio. 2023. "Population Knowledge and Practices and the Prevalence of Trypanosomes Circulating in Domestic Animals in Three Active Human African Trypanosomiasis Foci in the Republic of Congo" Microbiology Research 14, no. 3: 1067-1076. https://0-doi-org.brum.beds.ac.uk/10.3390/microbiolres14030071

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