Introduction

Lymphatic filariasis (LF) is known as one of the neglected tropical diseases caused mainly by Wuchereria bancrofti and transmitted through mosquito bites. It has been prioritized for global elimination through the Global Programme to Eliminate Lymphatic Filariasis (GPELF) since 2000. At that time, approximately 1.3 billion individuals living in 73 endemic countries were considered at risk of infection, and an estimated 120 million people were infected worldwide, with nearly 40 million suffering from clinically evident disease which varies from acute to chronic manifestations. The most prevalent clinical manifestations of LF include acute adenolymphangitis, hydrocele, lymphoedema and elephantiasis. While chyluria and tropical pulmonary eosinophilia (TPE) are less commonly reported (1, 2).

The goal of LF control is to interrupt disease transmission and reduce its associated morbidity and public health effects. Interruption of transmission targets the at-risk people to decrease the microfilarial load in the society below the level at which transmission of LF ceased (3). Despite the attained considerable accomplishment, the initial target of elimination by the year 2020 couldn’t be reached in all regions, prompting the WHO to set 2030 as the revised target year (4).

Based on WHO guidelines, in 2000 Egypt was among the pioneers to launch the national LF elimination programme (NLFEP), which was implemented via mass drug administration (MDA) using an annual dose of a combination of DEC (6 mg/kg) plus albendazole (400 mg) to all eligible individuals residing in LF-endemic areas (5). In 2017, Egypt no longer required MDA, as the elimination programme targets had been successfully attained, and WHO validated Egypt as the 1^st country in the Eastern Mediterranean region to successfully achieve LF elimination (6).

Doubtless, the full success of MDA programmes against LF depends on high rates of drug coverage and individual compliance to ensure consistent drug intake and treatment of all reservoirs of the disease (7). Besides, the key obstacles encountered implementation of these MDA programmes were limited awareness about LF and MDA (objectives and benefits), along with failure to recognize barriers that influence health behavior (limited time, access constraints, and logistic limitations). Additionally, the LF control efforts may fail due to not being suitable for community needs or conflicting with local beliefs about the disease (8, 9).

Despite the excellent overall MDA compliance with the Egyptian programme, the individual compliance may significantly vary. So, more studies should be performed to define the determinants of compliance and identify the best public health communication strategies to avoid noncompliance in the following elimination programmes (7).

This study aimed to identify the key factors influencing individual's compliance to MDA programmes against LF for providing evidence-based recommendations for future public health interventions and preventive strategy implementation.

Subjects and Methods

The study design

A retrospective cross-sectional study was conducted at a former anti-LF MDA-included area (Alkorain village, Sharqia governorate, Egypt) to identify the key factors influencing individual's compliance to the MDA programme against LF. All study participants were randomly selected from attendants of the Alkorain Endemic Diseases Centre from those who fulfilled the inclusion criteria during the period from 1^st August to 31^st December 2022. The inclusion criteria included Alkorain village residents aged ≥2 years at the time of MDA implementation, who had received at least one MDA round. Individuals with unclear information or those who were not permanent residents during the MDA were excluded.

The study participants were interviewed to recall their experienced MDA participation, and then data were recorded in a structured questionnaire, including sociodemographic data and previous MDA-associated data (compliance, number of received rounds, side effects, and causes of non-compliance). The estimation of the knowledge level about LF was performed according to Jaiyeola et al. (10) [a score of 1 was given for each correctly answered question, while a score of 0 was assigned for incorrect responses. Then the median score was determined, and those who scored less than the median were categorized as having "poor knowledge", whereas those who scored equal to or above the median were classified as having "good knowledge"].

Statistical analysis

The data were analyzed using the Statistical Package for the Social Sciences (SPSS) 22.0 software (IBM Microsoft). Kolmogorov-Smirnov test was used to test quantitative data normality of distribution. Qualitative data were described using number and percent. Quantitative data were described using range (minimum and maximum), mean, standard deviation. The comparison between groups was done using Chi-square test and Monte Carlo tests (when more than 20% of the cells have expected count less than five). Binary logistic regression analysis was used to analyze the relationship between a binary dependent variable and one or more independent variables. P value <0.05 was adopted as the level of significance and P value <0.001 was considered as highly significant.

Results

The study participants were 75 individuals involved in the previous MDA programme, and their retrospectively collected data revealed that 65.3% underwent all five rounds of MDA, and 85.3% didn't experience any side effects. The most mentioned side effect was dizziness (10.7%). While 34.7% of them mentioned non-compliance to all MDA rounds, mostly due to discontinued drug delivery by the health team (57.7%) (Table 1). Moreover, there was no statistically significant difference between males and females in experiencing side effects from the previous MDA (P= 0.707). The proportions of experiencing side effects were 15% and 14.5% in males and females, respectively (Table 2).  

The study participants revealed that the rate of full MDA compliance was significantly influenced by individual’s age, educational level, and knowledge level about LF (P< 0.05). Adults showed higher compliance (74.1%) compared to children (42.9%), while participants with good knowledge were more compliant (76.5%) than those with poor knowledge (41.7%), and university/academy attendants displayed higher compliance (91.7%) compared to illiterate and lower educational levels. Besides, compliance was non-significantly higher among males (75%), and governmental employees (92.3%) compared to females (61.8%) and other occupations, respectively (P> 0.05) (Table 3).

The univariate logistic regression analysis showed that adults had significantly higher odds of compliance with all MDA rounds compared to children (cOR = 3.81, P= 0.013). While females appeared to have non-significant lower the odds of full compliance compared to males (cOR = 0.54, P = 0.293). While compared to government employees, students showed significantly lower odds of full compliance (cOR= 0.11, P= 0.043). Besides, participants with elementary school education had significantly lower odds of compliance compared to those with academy/university education (cOR= 0.02, P= 0.004). In addition, participants with a good level of LF knowledge had significantly higher odds of compliance (cOR= 4.55, P= 0.004) compared to those with poor knowledge. Whereas the multivariate analysis indicated that the level of education could be the most significant independent predictor of full MDA compliance, as elementary education remained significantly associated with lower odds of compliance (aOR= 0.03, P= 0.028) compared to academy/university-level education (Table 4).

Discussion

LF is a neglected tropical disease which typically occurs when filarial parasites are transmitted to humans through mosquito bites. Wuchereria bancrofti is responsible for more than 90% of infections in which man is the only definitive host. This disease can lead to significant morbidity, disability, and economic burden on both individuals and communities (11). Since ancient Egyptian times, LF has been recognized especially in Nile Delta region. In 2000, with reference to WHO recommendations, Egypt was among the pioneers to launch the NLFEP based on implementation of MDA, vector control measures, morbidity management, and prevention of disability (5). In 2017, Egypt was the first of the eastern Mediterranean countries to be acknowledged by WHO for attaining the successful elimination of LF (2).

In the present study, most of participants (65.3%) underwent all 5 rounds of the prior anti-LF MDA programme. In this context, Abd Elaziz et al. (12) stated that the population's compliance rate to all anti-LF  MDA rounds was 85.3% in various Egyptian villages. While in a study on residents of former LF-endemic areas in 5 Egyptian governorates, Abdel-Shafi et al. (13) found that 71.7% of studied people received all MDA rounds. Moreover, the survey performed by Dahesh and Ibrahim (14) in some Egyptian villages of Giza governorate, revealed that 73.8% of respondents received MDA against LF. In our study, 34.7% of MDA-included individuals mentioned non-compliance to all rounds of the previous MDA, due to discontinued drug delivery by the health team (57.7%), fear of side effects (19.2%), pregnancy (11.5%), and non-presence at home during time of the next round (11.5%). These findings could reveal the logistic challenges and limited resources during MDA implementation in this village. Conversely, in Egyptian villages, Abd Elaziz et al. (12) clarified that reasons for non-compliance to MDA were absence from home (28.3%), pregnancy (23.3%), fear of adverse reactions (12.6%), and missed drug delivery by the team (10.9%). However, in an Indian LF-endemic district, Ratna et al. (15) found that the most frequently mentioned reason for MDA non-adherence was being not interested in participation (69%).

The studied participants revealed that the rate of full compliance to the prior anti-LF MDA rounds differed significantly by age, educational level, and LF knowledge level (P˂0.05), with higher compliance among adults, those with good knowledge about LF, and university/academy attendants. However, the compliance was non-significantly higher among males and governmental employees.

The identified higher compliance rate among adult individuals, is in accord with studies conducted by Abd Elaziz et al. (12), Mihretu et al. (16), and Kesuma et al. (17) in Egypt, Ethiopia, and Indonesia, respectively. While the discovered higher compliance rate among people attending academies/universities is in agreement with Titaley et al. (18) and Ratna et al. (15), who declared that individuals attaining higher education had higher compliance rates with the LF-MDA programme in Indonesia and India, respectively. In addition, the higher compliance rate among our study participants with a good LF knowledge level is in line with Abd Elaziz et al. (12), Ginandjar et al. (19), and Widawati et al. (20), in Egypt, Indonesia, and India, respectively.

In our study, the rate of full compliance to the previous MDA was non-significantly higher in males than females. Likewise, El-Setouhy et al. (7) revealed that rates of compliance to MDA did not differ significantly by sex in an Egyptian village (in Giza governorate). Whereas, Abd Elaziz et al. (12) found that compliance to MDA against LF in some Egyptian villages was significantly higher in males than females. Moreover, Government employees had a non- significant higher compliance rate (92.3%) compared to other occupations. This finding is in accord with results reported by Ginandjar et al. (19) in Indonesia. Conversely, Titaley et al. (18) found formal sector workers were less likely to comply with anti-LF MDA programme compared to housewives in Indonesia.

In the present study, the univariate logistic regression analysis examining factors influencing full MDA compliance showed that adults, males, government employees, those with academy/university education and those with good LF knowledge had significantly higher odds of compliance with all MDA rounds compared to children, females, students,  those with elementary school education and those with poor LF knowledge, respectively. However, the multivariate analysis indicated that the level of education could be the most significant independent predictor of full MDA compliance, as elementary education remained significantly associated with lower odds of compliance (aOR= 0.03, P= 0.028) compared to academy/university-level education.

Generally, adults typically have greater health awareness and can independently make their own medical decisions, while children are more reliant on their guardians in their medical service seeking behavior (21). Moreover, the gender differences in compliance, with males showing higher adherence, have been variably reported in the literature. Likewise, Shuford et al. (22) have reported higher compliance among males due to more exposure to health campaigns or occupational mobility, while Cantey et al. (23) have declared the higher compliance among females due to their role in family health decisions. Doubtless, government employees have easier participation in public health programmes, and relatively higher trust in governmental health interventions, so formal employment can be associated with better health-seeking behavior and MDA participation (21). Whereas participants with good knowledge about LF were more likely to comply due to their awareness of the role of MDA programmes in prevention and elimination of LF transmission and its consequences (24). Importantly, higher educational attainment can enhance comprehension of health messages, understanding risks, and trusting public health interventions, thereby facilitating adherence (25).

In the current study, 85.3% of the participants can tolerate drugs of anti-LF MDA rounds without any side effects. While the most experienced side effect was dizziness (10.7%), followed by nausea/vomiting, fever, and body aches. These results are in accord with Abd Elaziz et al. (12), who found that anti-LF MDA-associated side effects were reported by only 18.5% of individuals receiving mass therapy in various Egyptian villages. Dizziness was the most common adverse reaction mentioned by MDA-compliant persons (14.8%), followed by nausea or vomiting and fever. In addition, Inkane et al. (26) stated that only 6.85% of individuals who received the mass therapy against LF experienced side effects in India. However, in Kenya, Kulkarni et al. (27) reported that the incidence of MDA-associated adverse reactions in a LF-endemic district was 14.68%, and the most common mentioned side effect was fever (96.53%), followed by dizziness (1.73%).

In this study, there was a non-significant difference between males and females in experiencing side effects from previous MDA (P˃0.05) with a higher prevalence of side effects mentioned by females (73.3%) than males (26.7%). Similarly, Lima et al. (28) and Khaemba et al. (29) demonstrated that female participants non-significantly experienced more MDA-associated adverse events than males in Brazil and Kenya, respectively. Conversely, in Egypt, Abd Elaziz et al. (12) demonstrated that female participants significantly experienced more MDA-associated adverse events than males.

Conclusions

Our study findings conclude that the individual's age, educational level, and level of knowledge about LF can play a significant role in full compliance to anti-LF MDA programmes. Besides, the higher compliance rates were found among adults (74.1%), those with good knowledge (76.5%), and university/academy attendants (91.7%). While the multivariate analysis revealed that higher educational attainment could be the most significant independent predictor of full compliance to anti-LF MDA programmes. So, MDA programmes should prioritize targeted, accessible, and culturally appropriate health intervention strategies, particularly for populations with lower educational levels. Finally, further wide-ranging studies are required to clearly understand the key factors influencing individual compliance to MDA programmes against LF.

Acknowledgements

 The authors would like to express their sincere gratitude to Dr. Khaled Mohammed Mamdouh, Director of Alkorain Endemic Diseases Centre, for his valuable support and for facilitating the conduct of this study.

Conflict of interest statements

The authors declare that there is no conflict of interests.

Ethics approval

The ethical approval was obtained from the Research Ethics Committee of the Faculty of Medicine, Benha University, Banhā, Egypt (Approval No. MD 18-7-2022). The study was conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from all adult participants prior to enrolment.

Artificial Intelligence Statement

The authors declare that there was no use of AI-assisted technologies for assisting in the writing of the manuscript.