Knowledge and attitude towards cutaneous leishmaniasis among rural endemic communities in Shara’b district, Taiz, southwestern Yemen

A cross-sectional survey-based study was carried out in five areas of Shara’b district in Taiz governorate, namely, Nakhla, Alamjood, Bani-Ziad, Bani-Sarry and Bani-Wahban (Fig. 1). Taiz governorate (44.01° E, 13.34° N) is located in the southwestern part of Yemen, 280 km from Sana’a, the capital. Shara’b district was selected because a recent study confirmed that it is endemic for CL [10]. The five abovementioned areas of Shara’b district were selected by simple random sampling from the 11 known CL-endemic areas identified by Asmaa et al. [10]. The administrative district of Shara’b is divided into two sub-districts: Shara’b As-Salam, which covers an area of 210 km² and has a population of 146,650 and Shara’b ar-Rawnah, which encompasses an area of 417 km² and is home to a population of 186,955. Shara’b district is mountainous with some valleys and lies at an altitude of approximately 2000 m above sea level. Hence it can be described as a highland district. A number of aqueducts can be found near villages in the district and water is permanently present in these aqueducts throughout the year. The climate in this highland district varies from arid to wet, with an annual rainfall of 600–800 mm. It is cold in winter and warm in summer, with a mean annual temperature of approximately 23 °C.

Five hundred households were involved in this study. The household was selected as the sampling unit because decision making takes place at the household level. The five selected areas are almost homogeneous in terms of population size. Therefore, 100 households were selected from each area by simple random sampling using a list compiled by local administrators. During the research team visits to the study area, the head of each selected household, or another member if the head was not available, was invited to participate in this study. Verbal consent was obtained from each participant after they had been provided with an adequate explanation of the nature and objectives of this study. Only those who agreed to participate were interviewed. The study protocol was approved by the Medical Ethics Committee of the University of Taiz, Yemen. The principal investigator coordinated the interview process and also conducted daily spot-checks and reviews of the completed questionnaires to ensure the completeness and consistency of the collected data.

The minimum sample size required for this survey was calculated according to the WHO’s practical manual for sample size determination in health studies [14]. As previous data on the knowledge about and attitude towards CL in Yemen were unavailable, a 50% level of knowledge was considered, with a 95% confidence level and 5% level of significance. Thus, 384 was yielded as the minimum number of participants required for this study. However, to ensure that this sample size would be achieved, 500 households was targeted and used for the probability proportional to size sampling method in order to allow for non-participation and incomplete questionnaires.

The design, setting, analyses and reporting of this study adhered to the STROBE guidelines and criteria for cross-sectional studies in epidemiology [15] (see supplementary file 1).

The questionnaire was composed of four sections (see supplementary file 2). Section 1 consisted of questions designed to obtain data on the participants’ sociodemographic characteristics, such as age, gender, education level, occupation and number of household members. Section 2 contained questions on knowledge about CL that were developed to understand the participants’ ability to identify the disease, its signs and symptoms, its vector, as well as the peak period of incidence, treatment options, and prevention measures. Section 3 consisted of questions on knowledge about sand flies that were designed to determine the participants’ ability to identify and differentiate sand flies from other flying insects, as well as the breeding sites, time of biting and the disease(s) that can be transmitted by sand flies. Section 4 contained questions that were developed to gain an understanding of the participants’ attitudes towards CL in comparison to their attitudes towards malaria in terms of severity, prevention and curability. Malaria was selected as the comparison disease because the selected district is a malaria-endemic area and it is considered to be sufficiently well known among the public at large. This final section concluded with a question on the participants’ sources of information. Most of the questions were open-ended in order to avoid any false impressions due to guessing. However, the participants were requested to answer some questions by choosing one of three options: ‘no’, ‘yes’ or ‘I don’t know’. The participants were interviewed face to face in their household setting by three assistants who had received adequate training on the administration of the questionnaire and on the purpose of this study.

Data were entered into Microsoft Office Excel spreadsheets and checked for accuracy and completeness by two research assistants. Data analysis was done using the Statistical Package for the Social Sciences version 18 (IBM Corp., New York, USA). Descriptive statistics such as frequency, percentage and mean were used to describe the knowledge and attitude components and the explanatory variables. The chi-square test was used to examine the association between the good knowledge scores and the explanatory variables such as age, gender, education level, occupation and household size. A multivariate logistic regression analysis was also performed to identify the significant determinants of good knowledge of CL and the sand fly vector, where a P level ≤ 0.25 in the univariate analysis was considered as the criterion for the inclusion of variables in the multiple logistic regression models [16]. Adjusted odd ratios (AORs) and their corresponding 95% confidence intervals (CIs) were calculated based on the final models. The significance level for all tests was set at P < 0.05.

Knowledge and attitude were scored according to the method described in [17], with some modifications to fit the studied disease. Each correct response to a question was assigned a score of 1 and each incorrect or unsure response was assigned a score of 0.

Knowledge about CL was assessed according to the responses given to five items. The correct answers to these five items were as follows: 1) a symptom of CL is a skin ulcer, skin wound or skin scar; 2) CL is transmitted through sand fly bites; 3) the peak of CL incidence is summer; 4) CL can be treated by herbal medicine, chemotherapy, or cauterisation; and 5) preventive measures include treating patients, vector control and improving awareness. Thus, the total knowledge score for CL ranged from 0 to 5. Knowledge scores between 0 and 3 were considered to indicate poor knowledge while scores of more than 3 were considered to denote good knowledge.

Knowledge about the sand fly vector was also assessed on the basis of five items. The correct responses to the five items were as follows: 1) the sand fly is the vector of CL; 2), the biting time is at night; 3) the breeding sites are holes in dry trees, and cattle and sheep dung; 4) the methods of control include using bed nets and insecticides and minimising close contact with animals by situating animal stables as far as possible from dwellings. As above, the total knowledge score for the sand fly vector ranged from 0 to 5 with a score of 0 to 3 indicating poor knowledge and a score above 3 indicating good knowledge.

Attitude towards CL was assessed based on the responses to three items. The correct answers were as follows: 1) CL is less dangerous than malaria; 2) CL can be treated; and 3) CL can be prevented. Each correct answer to an attitude items was given a score of 1. An attitude score of 0 or 1 was considered to denote a negative attitude while a score of 2 or 3 was considered to represent a positive attitude.

Of the 466 participants included in the final analysis, 62.7% were male and 37.3% were female. Most of the participants (65.7%) were aged between 18 and 40 years and approximately one third (34.3%) were older than 40 years. In respect of education level, 21.5% of the participants were non-educated while 39.7% had completed a secondary school level of education. Just over half (53.2%) of the participants were university students while 19.3, 14.8 and 7.5% were teachers, farmers and housewives, respectively. Most of the interviewed households (53.0%) were composed of five to nine members. Table 1 provides a full breakdown of the sociodemographic characteristics of the study participants.

Table 2 shows the results for the participants’ knowledge about the signs and symptoms, transmission, prevention and treatment of CL. From the table it can be seen that 76% (364/466) of the participants had seen a CL case before. When participants were asked about the signs and symptoms of CL, 39.5% (184/466) correctly answered that a skin ulcer is the main symptom of CL while 40.2% were either unable to mention any signs or symptoms of CL (25.3%) or mentioned non-specific symptoms (14.9%). With regard to mode of transmission, only 12.9% (60/466) knew that CL is transmitted by sand flies while 61.4% (286/466) were unable to mention any mode of CL transmission. Moreover, 25.8% of the participants demonstrated misconceptions about the transmission of CL, mentioning mosquitoes, autoinfection, and direct person-to-person skin contact. The results in the table also show that 35.2% of the participants correctly stated that the peak incidence of CL occurs in summer while 47.0% did not know the main transmission season.

As regards treating the disease, 35.8, 19.7 and 2.1% correctly stated that the methods of treatment for CL are herbal medicine, chemotherapy and cauterisation, respectively. As for prevention, the majority of the participants (62.9%) could not cite any preventive measure against CL while 20 and 7.3% correctly mentioned that treating infected patients and controlling the sand fly vector are preventive measures. Therefore, from the above results, the majority of the participants (77.7%) were found to have poor knowledge about CL (Table 3).

With regard to the participants’ sources of information, most (74.5%, 347/466) had heard about the disease through their families, relatives, and friends while 17.8% (83/466) had a personal history of infection. A further 6.2% (29/466) and 0.8% (4/466) had heard about CL at educational institutions and through social media, respectively.

Table 4 contains the results for the participants’ knowledge about sand flies and their role in disease transmission. Interestingly, approximately half of the participants (49.1%) were able to identify and differentiate sand flies from other flies. However, only 14.8% (69/466) of the participants mentioned that CL is transmitted by sand flies. The majority of the participants (63.5%) did not know whether or not sand flies could transmit diseases, but 13.7% of the participants stated that sand flies can transmit malaria.

With regard to breeding sites, 16.7% (78/466) and 5.4% (25/466) of the participants mentioned cattle and sheep dung, and holes in dry trees, respectively, but the majority (55.6%) did not know the answer. With respect to biting time, 21.7% of the participants correctly stated that sand flies bite during the night-time while 17.6% thought that sand flies bite at any time of the day. The majority of the participants (58.2%) were unable to mention any control measures against sand flies while 40.1% correctly answered that sand flies can be controlled by using bed nets, spraying insecticides, improving sanitation and avoiding breeding sites. Therefore, from the above results, it was found that about two-thirds of the respondents (67%) had poor knowledge about the sand fly acting as vector of CL (Table 3).

Table 5 gives the results for the participants’ attitude towards CL. A total of 205 (44%) participants considered CL to be a serious condition and more dangerous than malaria while 41.0% believed that CL is a mild infection. Interestingly, the majority of the participants (82.8%) showed a positive attitude and thought that the disease is curable while only 3.9% believed that the disease cannot be cured. However, 61.2% of the participants believed that CL cannot be prevented. From the analysis of these results, it is apparent that approximately half of the participants (49.6%) had a negative attitude towards CL (Table 3).

Table 6 shows that the percentage of participants aged over 40 years with good knowledge about CL is significantly higher than that of participants aged 18–40 years (28.1 vs. 19.3%; P = 0.029). Also, a significantly higher percentage of the participants with good knowledge about CL are male compared to female (25.3 vs. 17.2%; P = 0.042). The results in Table 6 also show that the percentage of participants with good knowledge about sand flies is significantly higher among those aged over 40 years and farmers as compared to younger and non-working participants, respectively (46.4 vs. 30.9%; P = 0.014). Also, the percentage of participants with good knowledge about sand flies is significantly lower among those with a primary level of education as compared to non-educated participants (22.6 vs. 40.0%; P = 0.022). On the other hand, the distribution of the scores for a positive attitude towards CL among the different groups is comparable (P > 0.05).

The outcome of the multivariate logistic regression presented in Table 6 shows that age and gender were significant determinants of good knowledge about CL and sand flies, respectively. The participants aged over 40 years were about two times more likely to have good knowledge about CL as compared to the younger participants (AOR = 2.40; 95% CI = 1.05, 5.50). Interestingly, male participants were 0.71 times less likely to have good knowledge about sand flies compared to their female counterparts (AOR = 0.51; 95% CI = 0.32, 0.82). The other sociodemographic variables (occupation and education level) were not retained in the multivariate analysis.