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Keywords:

  • lymphatic filariasis;
  • drug delivery;
  • elimination;
  • rural areas;
  • India

Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

Lymphatic filariasis (LF) is targeted for global elimination. Repeated annual single-dose mass treatment with antifilarials has been recommended as the principal strategy to achieve LF elimination. This requires an effective and sustainable strategy to deliver the drug, diethylcarbamazine (DEC), to communities. In this study, a new drug delivery strategy – community-directed treatment (comDT) – was developed and implemented and its effectiveness compared with that of the traditional health services-organized drug delivery, in rural areas of Tamil Nadu, India. Qualitative and quantitative data showed that the communities and health services were able to distribute the drug in almost all villages. The drug distribution rate and treatment compliance rate of comDT and health services treatment were statistically compared after adjusting them for clustering. Under the comDT 68% (n=20 villages; range: 0–97%) of the population received DEC, compared with 74% (n=20 villages; range: 48–95%) with the health services treatment strategy (P > 0.05). However, only about 53% (range: 0–91%) of comDT recipients and 59% (range: 32–79%) of those who received DEC from the health services consumed the drug (P > 0.05). Although statistically not significant, the distribution and compliance rates were lower under the comDT strategy. Also, the strategy’s operationalization appears to be difficult because of some social factors, and the tradition of communities’ dependence on health services for treatment, whereas health services-organized distribution was much less cumbersome and found to be more acceptable to people. However, the distribution (74%) and compliance rates (59%) achieved by health services were also only moderate and may not be adequate to eliminate LF in a reasonable time frame. Health services manpower alone may not be sufficient to distribute the drug. We conclude that drug distribution by health services is the best option for India and participation of the community volunteers and village level government staffs in the programme is necessary to effectively distribute the drug and attain the desirable levels of treatment compliance to eliminate LF.


Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

Lymphatic filariasis (LF) is targeted for global elimination as a public health problem (Tropical disease research [TDR] 1996; Ottesen 2000), defined as a 5-year cumulative transmission rate of less than one new infection per 1000 susceptible individuals (WHO 1999). Treatment of the entire endemic population at annual intervals with a single dose of antifilarial drugs – diethylcarbamazine (DEC) and/or ivermectin or either drug in combination with albendazole – has been recommended as the principal strategy to achieve the goal of LF elimination (Ottesen et al. 1997, 1999). While efforts to identify the optimum treatment continue, DEC remains the drug of choice for LF control/elimination programmes in India. It is estimated that four to six rounds of annual mass treatment with antifilarials of a very high proportion of the target population are necessary to achieve the elimination of LF (Ottesen et al. 1999). Recent studies confirmed that four to five rounds of annual mass treatment with a single dose of DEC appreciably reduce microfilaraemia prevalence and the intensity and transmission of infection (Das et al. 2001a, b). While the long-term social and economic benefits of LF elimination to the affected communities are immense (Ramaiah et al. 2000a), the annual single dose mass treatment with DEC yields no immediate perceivable benefits (Das et al. 2001a). Therefore, sustenance of several rounds of mass treatment with high compliance rate poses a challenge to public health personnel and requires effective and community friendly drug delivery strategies. This is particularly so in India, which is the largest endemic country with an estimated 450 million people at risk of infection.

In rural areas of India, traditionally, it is the state-run primary health care system that caters to the health needs of people. However, rural communities in Africa played a pivotal role in the distribution of ivermectin for the control of onchocerciasis (WHO 1996; Morel 2000). This system of drug distribution by community members, known as community-directed treatment or ComDT, has become highly acceptable and generated hope that the communities themselves can sustain the onchocerciasis control programmes. Therefore, WHO/TDR initiated a multicentre study to test the feasibility of ComDT for elimination of LF. A system of ComDT was developed and implemented and its effectiveness compared with that of the traditional health services-implemented treatment in Ghana, Kenya, Myanmar and Vietnam and five sites in India. The results in one study site, the rural areas of Tamil Nadu, south India, are presented in this paper. The region is endemic for bancroftian LF.

Study area

The study was conducted in rural areas of four contiguous blocks (subunits of a district) in Villupuram district in the southern state of Tamil Nadu, India. Agriculture and weaving are the main occupations; the literacy rate is in the range of 35–50%. LF is an important public health problem, with microfilaraemia prevalence rates up to 21% (Ramaiah et al. 1996a) and disease rates up to 27% (Vector Control Research Centre, unpublished data). However, people’s knowledge of the disease process and its control is poor (Ramaiah et al. 1996b). LF inflicts a considerable social and economic burden on the affected communities (Ramaiah et al. 2000a).

Structure of health services

The state-run primary health care system caters to the health needs of rural people in India. It operates through the network of primary health centres (PHCs). A typical PHC serves about 30 000–35 000 people in 30–35 villages. PHCs are located in relatively bigger villages (population size >2000) and headed by a medical officer. Each PHC is divided into five to eight sub-health centres (SHCs), which are maintained by a village health nurse (VHN). SHCs are located in medium-sized villages (population size 1000–2000). Each SHC consists of two to five smaller villages (population size <1000) without resident health personnel. However, these villages are visited by VHNs once in a week or so, primarily to look after the health needs of pregnant women and children. Thus, the PHC system covers all villages and VHNs are instrumental in health care delivery.

Structure of communities

The study communities consist of multi-religious and multi-caste groups. Some caste groups, who are economically and socially disadvantaged, live 1–2 km away from the main village (henceforth referred to as subgroups). By and large main and subgroups live in harmony, although main groups dominate the decision-making process. The villages have an elected body of representatives, the Panchayat, which is responsible for governance and implementation of welfare measures. Its leader and other elected members represent various caste-groups and play key roles in the decision-making process and almost all village affairs.

Study design and arms

Our main objective was to compare the feasibility and effectiveness of ComDT and health services (implemented) treatment (HST). Therefore, the study included two arms: ComDT and HST. Under the ComDT strategy, communities were given the responsibility to distribute DEC. Under the HST strategy, health services personnel from PHCs distributed DEC. The study was implemented in four blocks and two blocks each were randomly allocated to ComDT and HST arms.

The study population consists of 520 000 people: 270 000 in the ComDT arm and 250 000 in the HST arm. The ComDT arm has eight PHCs with 56 HSCs and 246 villages and the HST arm six PHCs with 54 HSCs and 238 villages.

Methods

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

Implementation of ComDT

ComDT envisages distribution of drugs by communities, who alone decide the timing, duration and mode of distribution, select drug distributors and maintain records, with a minimum role for health services. However, ComDT is a new concept in India; hence we first briefed the health personnel, who subsequently informed communities about the concept of ComDT. We held meetings with district and PHC level medical officers and the para-medical staff, discussing (i) the public health importance and social and economic burden of LF (Ramaiah et al. 2000a), (ii) new initiatives to eliminate LF (Ottesen et al. 1997), (iii) the advent of easier and more feasible annual single dose DEC treatment regimens (Ottesen et al. 1997), (iv) the concept of ComDT and its contribution to onchocerciasis control in Africa (WHO 1996) and potential for LF control/elimination in India, and (v) the need to sensitize the communities to undertake ComDT. Health staff were told to play only a minimum supportive role in terms of providing advice and clarifying the doubts of the community members and that the entire process of decision-making and drug distribution was to be left to the communities. At PHC level, medical officers trained all health workers on the dosage of DEC, exclusion criteria and side-effects caused by the drug and their management.

In order to sensitize the communities regarding ComDT, the VHNs visited all the villages, organized meetings of community leaders and members and explained to them the public health importance of LF in the study region and the new opportunities available to eliminate the disease through annual single dose mass treatment. The VHNs encouraged community members to take the responsibility of drug distribution and treatment for the well-being and welfare of their communities. The health services personnel also explained that communities were free to take decisions and work out the modalities of drug distribution. Community leaders were free to select the drug distributors, who were trained by VHNs in the mode of transmission of filariasis, the role of the drug in the control and elimination of LF, in drug dosage and side-effects caused by it.

Implementation of HST

In the HST arm, the Directorate of Public Health and Preventive Medicine, Government of Tamil Nadu, Chennai, directed the distribution of DEC through the PHC system. PHC staff members under the supervision of medical officers undertook all activities connected with drug distribution. In this arm also, medical officers trained health workers.

Dosage of DEC and exclusion criteria

DEC was distributed at the dose of 6 mg/kg body weight. The strength of the tablets used was 50 and/or 100 mg. But as weighing hundreds of thousands of people is cumbersome, the drug was distributed according to age based on a relationship between weight and age (weight=6.93 ± 1.62 age, R2=0.79, r=0.88, P < 0.01) (Vector Control Research Centre, unpublished data). The 1–5-years age group (mean weight 11 kg) was administered 50 mg of DEC, the 6–10-years age group (mean weight 19 kg) 100 mg, the 11–15-years age group (mean weight 28 kg) 150 mg, the 16–20-years age group (mean weight 35 kg) 200 mg, the 21–25-years age group (mean weight 45 kg) 250 mg, the 26–30-years age group (mean weight 53 kg) 300 mg, the >30-years age group (mean weight 59 kg) 350 mg. Many people do remember the precise year of their birth and others do so by relating their birth to an important event in the village/region/country. Children < 1 year, pregnant women and people with serious illness were excluded.

Quantitative and qualitative evaluation of DEC distribution under ComDT and HST strategies

While the communities distributed DEC between December 1998 and March 1999 in the ComDT arm, the health services did so from 22 to 26 March 1999 in HST arm villages. We visited each of the ComDT PHCs two to three times to monitor the progress of implementation of ComDT. Soon after drug distribution was completed, we evaluated the distribution process and the effectiveness of HST and ComDT strategies in terms of (i) the extent of drug distribution and treatment compliance achieved and (ii) people’s and health personnel’s perception of it.

The drug distribution rate (number of people received drug/total population × 100) and treatment compliance rate (number of people received and consumed drug/total population × 100) were obtained through a quantitative household questionnaire survey in 20 villages each in ComDT and HST arms. As the presence or absence and type of health facility may influence the distribution of the drug, all the villages in each arm were stratified into PHC and HSC villages and no health facility villages and then we selected the study villages following a simple random procedure. All villages in each stratum were assigned serial numbers and two villages with PHC, eight with HSC and 10 with no health facility (total of 20 villages per arm) were selected using a list of random numbers generated by EPINFO software.

In each village, all streets were listed and four were randomly chosen to sample the households. In each selected street five households were randomly selected. Thus, a total of 20 households were sampled to collect data. Subgroup streets or households, if present, were sampled proportionately. At the household level, details on the number of inhabitants, their sex and age were gathered. The head of the household was asked whether he or she was aware of the drug distribution. Then, each household member was interviewed with the help of a structured questionnaire that included the following questions: (i) did you receive DEC or not? (ii) if yes, how many tablets did you receive? (iii) did you swallow the DEC tablets or not? (iv) if yes, did you have any side-effects after swallowing? and (v) if yes, what were those side-effects? For absentees, the information was elicited from the head of the household.

The people’s and health personnel’s perception of the drug distribution was evaluated using qualitative research methods, in six randomly selected villages in each arm from among 20 villages selected for household survey. We used focus group discussions with community members (n=10) and semi-structured interviews (Pelto & Pelto 1978) with key informants (n=24), medical officers (n=4), health workers (n=10) and community drug distributors (n=9) to gather data.

Data analysis

All qualitative interviews were recorded on audiocassettes, transcripted and translated from Tamil into English. They were entered into computer and analysed in the TEXTBASE BETA programme. Quantitative data were analysed with SPSS. Because of considerable variation in the population size of the study villages and the treatment coverage and compliance within the study arms, and in order to take into account the cluster structure in the data (Donald & Donner 1987; Rao & Scott 1992), the method proposed by Rao and Scott (1992) was used to test the significance of difference in distribution and compliance rates obtained with ComDT and HST strategies.

Results

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

Drug distribution process

DEC was procured for the entire state of Tamil Nadu by the state level health administration. A couple of months before distribution, the drug was transported to the district headquarter town, from where it was sent to PHCs within the district. From the PHCs, the drug was sent to the HSCs, managed by VHNs, who finally handed it over to the leaders or distributors in the villages. In the ComDT arm, the communities took the responsibility of drug storage. There were no problems either with drug procurement or storage during the study period.

Community drug distributors, selected by village leaders, in the ComDT arm and VHNs and other health workers in the HST arm villages played important role in the distribution of DEC. Note that under the ComDT strategy and to some extent under the HST strategy also various categories of the local government employees were also involved in drug distribution (Table 1).

Table 1.   List of various categories of people involved in drug distribution under community-directed treatment (ComDT) and health services (implemented) treatment (HST) strategies Thumbnail image of

DEC was distributed house-to-house under the ComDT and HST strategies. In some villages in both arms supervised treatment was attempted but not always adhered to. DEC was distributed in the morning and evening. In many ComDT villages, the drug was distributed soon after it was handed over to the village leaders. In most ComDT and HST villages, distribution was completed in 2–3 days. Under the HST strategy, DEC was distributed over a fixed period of 5 days, as decided by the state level programme managers.

Results of quantitative household questionnaire survey

Quantitative data suggest that a vast majority of the households, 85% in HST villages and 75% in ComDT villages, were very well aware of drug distribution. The drug was widely perceived as a preventive measure against ‘elephantiasis’ problem. However, the awareness of the beneficial effects of DEC against hydrocele, a predominant clinical manifestation of LF, was very poor.

A total of 1919 people living in 397 households in ComDT arm villages (n=20) and 1950 people in 396 households in HST arm villages (n=20) were sampled to assess the drug distribution and treatment compliance rates (Table 2). The household questionnaire survey data show that DEC was distributed in 18 of the 20 villages (90%) under the ComDT strategy and in all villages under the HST strategy (Figure 1). Under ComDT 68% (1305 of 1919) and under HST 74% (1441 of 1950) of the total population received DEC (distribution rate) (Figure 2) (standard χ2=15.67; adjusted χ2=0.61; P > 0.05). But not all people who received DEC did consume it. Only 53% (1017 of 1919) (range: 0–91%) in ComDT arm villages and 59% (1151 of 1950) (range: 32–79%) in HST arm villages took the drug (standard χ2=15.41; adjusted χ2=0.90; P > 0.05). Hence about 15% of the population under both the strategies did not comply with treatment although they received the drug (Figure 2). The range of distribution rates was very large and the number of villages with relatively lower distribution rates was higher in ComDT villages (Figure 1). The range was much smaller and distribution rates were consistently higher in HST villages. Mean and median distribution rates were higher in HST villages (Figure 1). The variance inflation because of clustering (Rao & Scott 1992) in distribution rate was much higher at 32.88 in ComDT villages compared with 6.77 in HST villages (standard χ2=15.67; adjusted χ2=0.61). The respective figures for treatment compliance rate were 24.35 and 5.44 (standard χ2=15.40; adjusted χ2=0.90; P > 0.05).

Table 2.   Details of household survey carried out to assess diethylcarbamazine (DEC) distribution and treatment compliance in community-directed treatment (ComDT) and health services (implemented) treatment (HST) arms Thumbnail image of
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Figure 1.  Box plot showing the drug distribution rates in study villages. The box represents inter quartile range which contains 50% of values. The whiskers are lines that extend from box to the highest and lowest values, excluding outliers (open circles). A line across the box indicates the median.

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Figure 2.  Percentage of the population that received DEC and complied with treatment.

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Receipt of drug or compliance with treatment did not vary with sex or age group under either strategy (Table 3). While 69% of males and 67% of females received DEC in the ComDT arm, about 74% of both sexes did in the HST arm. However, under both strategies, treatment compliance was higher by 2% in females than in males. About 68% of the population of different age groups in the ComDT arm and 75% in the HST arm (except in the highest age group > 60 years) received DEC. Treatment compliance was lower in the highest age class (> 60 years) in both arms (Table 3).

Table 3.   Receipt of diethylcarbamazine (DEC) and compliance with treatment in different categories of people under community-directed treatment (ComDT) and health services (implemented) treatment (HST) strategies Thumbnail image of

While more than 72% of the main and subgroup populations received DEC under the HST strategy, only 56% of the subgroup population received DEC compared with 71% of the main group under the ComDT strategy. Fifteen percent of the total population failed to comply with treatment under either strategy (Table 3).

Presence of health facility, PHC or HSC did not seem to have much influence on the distribution of DEC as not much difference was observed in the proportion of people receiving DEC in villages with and without health facility. However, compliance with treatment was better in villages with PHCs in both arms (Table 3).

People’s opinion of drug distribution and ComDT

Qualitative data showed that in both study arms, people were very positive about the drug distribution programme and thought that it was initiated by the government for their welfare. Although community leaders in most ComDT arm villages did express their willingness to implement it, their commitment and active participation in the ComDT programme was found to be inadequate in many villages. They felt that the PHC health workers, village level government employees such as Village Welfare Officers, teachers, Integrated Child Development workers, etc. are more appropriate personnel to distribute the drug. Therefore, in many ComDT villages the community leaders also involved village level government employees in drug distribution (Table 1). One of the village leaders said during an in-depth interview: ‘I am authorized to give this type of work to these people (employees). They have to do this type of work’. The community leadership appears to have implemented the programme more as an obligation to the local medical officer and health personnel than as a welfare measure for the local population. The health workers also thought that the leaders are economically better off than other villagers, more interested in politics, business and occupational activities and show little interest in welfare activities. A VHN said, ‘The village leaders are rich and busy and will not do this (drug distribution) properly’. Other factors that hindered ComDT were group and caste conflicts, and lack of people’s confidence in the competence of community members to give the drug (treatment), etc. One key-informant said that ‘People will have faith only in health department staff. It will be better if the department staff distribute the drug’. Most health workers felt that it was very difficult to contact village leaders to appraise them of the ComDT programme because they often were travelling or pre-occupied with other activities.

Discussion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

We examined whether rural communities themselves can take on the responsibility of distribution of DEC to eliminate LF. DEC is a safe drug that is used extensively in control programmes (Hawking 1978); the single dose regimen caused no untoward reactions and was well accepted by communities (Das et al. 2001a). Therefore, DEC delivery and treatment may not require very close involvement of medical personnel and can be entrusted to communities, as has been done with ivermectin in Africa (WHO 1996; Morel 2000).

This study showed that communities are able to distribute DEC in 90% of the villages. Under the ComDT strategy, 68% of the population received DEC and 53% complied with treatment. However, health services are more effective. Under the HST approach, DEC reached each and every village and 74% of the population received DEC and 59% complied with treatment (Figures 1 and 2). Thus, with the HST approach, the distribution and compliance with treatment was higher by 6% (Figure 2), a crucial difference, as the percentage of population treated is an important determinant of LF elimination (Plaisier et al. 2000). Moreover, implementation of ComDT was constrained by various social and operational factors, including (i) difficulties encountered by health personnel in sensitization of communities where the knowledge of the disease is poor (Ramaiah et al. 1996b); (ii) poor response of community leadership to the concept of ComDT; (iii) people’s reluctance to accept the drug from community drug distributors, whose knowledge of the drug is poor; (iv) group and caste conflicts and identification of distributors with one or the other group or caste in some villages. While not all these factors are common to all villages, most were affected by one or more. These factors are likely to have a much stronger negative effect in less developed states such as Uttar Pradesh and Bihar, which account for about 40% of the endemic population in India (National Filaria Control Programme 1995).

Qualitative data also showed that communities are more concerned with more basic needs such as drinking water, roads and schools, etc., in whose improvement leaders showed keen interest. There was no similar enthusiasm for the drug distribution programme.

The opinions of key informants and focus group participants suggest that communities perceive drug distribution as the responsibility of the health workers. They have fewer complaints and are very much willing to accept the drug from health workers. Health workers regularly visit communities for child immunization and maternal and school health, etc., which accrue perceivable benefits to communities, and are therefore perceived as more appropriate people to distribute DEC also. While the distribution rate was less in subgroups under ComDT strategy, it was similar in main and subgroups in the HST arm (Table 3), suggesting that health workers reach all segments of the population. Negligence in distributing the drug to certain groups of the population may lead to low compliance and a remaining pool of infected individuals who will present a serious barrier to the possibility of LF elimination in a community.

Four to six rounds of annual mass administration of antifilarials with high levels of treatment compliance (80–90%) are necessary to eliminate LF (Ottesen et al. 1999). In this study, even the health services were able to achieve only 59% compliance with treatment. Shortage of manpower is one of the reasons for inadequate distribution (Ramaiah et al. 2000b). For example, a district in India consists of about 1.8 million people in 340 000 households. The district health infrastructure includes 50 PHCs and each PHC caters to the health needs of 30–35 villages with about 30 000–35 000 population. A typical PHC will have 10–15 paramedical workers and each worker may not be able to distribute the drug to and follow up more than 1000–1500 people, suggesting that the number of health workers alone may not be sufficient to distribute the drug. The support of the community members and other village level staff involved in welfare activities such as nutrition and primary education, etc. is necessary to successfully implement the programme. Therefore, drug distribution under the overall leadership of health services with active involvement of community members and staff of the welfare programmes may be the best option to cover the target population and treat as many people as possible. Such an integrated approach has been used in other programmes, the most recent being polio eradication.

When a nationwide LF elimination programme is implemented, delivery of DEC to an endemic population of 450 million will become, perhaps, the largest ever drug distribution programme in India. The massive dimension of the programme combined with the necessity to achieve high levels of distribution and treatment compliance requires adequate advocacy and training of health services personnel and other village level workers and health education of communities.

Acknowledgements

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

The study received financial support from UNDP/World Bank/WHO/TDR (Grant no. 970628). We are grateful to Dr Siddhi Vinayak Hirve for visiting the study villages and giving valuable suggestions. The authors thank Mr S. Subramanian for his help in the statistical analysis of data, Drs Hans Remme, O.O. Kale and V. Kumaraswamy for their help in designing the study and keen interest and constructive comments. The co-operation of Drs Paul Kandasamy and Kamalakannan is gratefully acknowledged. We thank the members of the other study teams from Ghana and Kenya and India, who shared their experiences with us and made valuable comments. We are grateful to all community members and health personnel for their excellent co-operation.

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  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References
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