The Emerging Story of Disability Associated with Lymphatic Filariasis: A Critical Review

Globally, 40 million people live with the chronic effects of lymphatic filariasis (LF), making it the second leading cause of disability in the world. Despite this, there is limited research into the experiences of people living with the disease. This review summarises the research on the experiences of people living with LF disability. The review highlights the widespread social stigma and oppressive psychological issues that face most people living with LF-related disability. Physical manifestations of LF make daily activities and participation in community life difficult. The findings confirm the need for the Global Programme to Eliminate Lymphatic Filariasis (GPELF) to support morbidity management activities that address the complex biopsychosocial issues that people living with LF-related disability face.


Introduction
Lymphatic filariasis (LF) is a parasitic disease endemic in 81 countries. The global burden is 120 million people, with 40 million people chronically disabled by the disease and about twice that number suffering from covert lymphatic changes or kidney disease [1]. The World Health Organization (WHO) considers LF to be the leading cause of physical disability in the world [2].
LF is caused by three filarial nematodes: Brugia malayi, Brugia timori, and, most commonly, Wucheria bancrofti [3]. These parasites are transmitted via a number of different mosquito hosts, which vary geographically. The most common chronic manifestations of the disease are lymphoedema and hydrocele. Acute adenolymphangitis (ADL), bacterial infections that cause significant pain and fever, also occur in phases. Other less reported clinical expressions include lymphoedema of the breast, swelling of the vulva, and rheumatic and respiratory problems [4].
In 2000, the Global Programme to Eliminate Lymphatic Filariasis (GPELF) was created with the aim of eliminating LF by 2020. This programme is based on two ''pillars'': firstly, interrupting the transmission of the parasite by annual, community-wide mass drug administration (MDA), and second, alleviation of suffering of those with chronic manifestations of the disease [5,6]. The MDA programme is now well advanced with about half of the endemic countries having introduced the strategy [7]. However, morbidity management remains less widespread and successful. Only 26 of the 81 endemic countries have morbidity programs, and most focus only on addressing physical impairment [8]. Outside of Gerusa Dreyer's work [9], there are very few reported programs that support LF patients in actively participating in their communities and achieving greater independence in daily activities.
This paper aims to review the small but important body of qualitative research into the experiences of people living with LFrelated disability. Reviews of the social science literature on LF [10] and morbidity management [11] are available; however, no previous review has explored patient reported experiences of disability and management of the condition. Qualitative research is highly valuable, as it attempts to make sense of experiences from participants' lives and the meanings that people bring to them [12]. For the GPELF, high quality qualitative research is vital to inform the second pillar of the programme (alleviating the suffering of those disabled by LF).

Conceptual Framework of Review
The WHO's International Classification of Functioning, Disability and Health (ICF) is an internationally recognized disability framework [13]. The ICF defines disability as a result of not only disease and impairment, but also of disruptions to one's ability to engage in daily activities and participate in major life roles within their family and community (see Figure 1). The ICF was used as a conceptual framework to guide the search strategy for this review to explore LF patient experiences from a social model of health and functioning. Hence, this review included papers that explored the impact of LF on daily activities and community participation as well as articles that discussed the influence of social, cultural, and institutional impacts.
Articles were critically appraised using the McMaster University Critical Review Form -Qualitative Studies (Version 2.0), which guides systematic review of study purpose, design, sample, data collection and analysis, trustworthiness, conclusions, and implications [14]. This critical review form has previously been used to review literature in other disability studies [15,16]. A summary of the critical review form is found in Table 1. It is acknowledged that there are limitations to this review. A review of grey literature and articles not published in English could have included more articles for review.

Quality of Evidence
The review highlighted a worrying number of methodological issues within the papers. The majority of papers (seven articles) did not state, describe, or justify their research design, making it difficult to gain a perspective on the frameworks that informed the research. Descriptive clarity was lacking within the majority of articles (eleven articles), with the role and bias of the researchers rarely stated. Sampling was also poorly described by many articles and redundancy in data was often not discussed (eight articles). Analytical rigor in terms of descriptions of analysis and coding techniques was also insufficient in many papers (six articles), although it is acknowledged that limited publishing space makes this difficult. A number of papers (six articles) did not state whether informed consent or ethics approval was gained, highlighting worrying ethical concerns for research within disadvantaged communities.

Daily Activities
Domestic life and self care. The ability to complete household tasks such as cooking, washing, cleaning, and childcare is limited for women with LF-related lymphoedema [17,18]. Participants reported that acute attacks are particularly debilitating, leaving people dependent on family to assist with the simplest of daily activities such as dressing, bathing, and toileting [19]. In these situations, role reversal can occur, where parents become dependent on their children.
Mobility. Physical restrictions due to later stages of lymphoedema and hydrocele decrease people's ability to walk, stand, and sit for long periods and also people's ability to lift heavy loads [17,19]. Loss of mobility was reported to prevent people Within this model, health is seen to be not only the absence of a Health Condition, but also the individual's ability to complete daily Activities of necessity and their Participation in important life roles. Health and functioning is influenced by the existence of Environmental Factors (climactic environment, social attitudes, policies, services, etc.) that can be barriers or supports to health and functioning. Personal Factors (poverty, education level, gender, etc.) also influence health and functioning, depending on the environment a person lives within. Health and functioning is seen within this model as being not only an outcome of a health condition, but also of the other five domains that interact. Hence, health and functioning is seen to depend on context (Environment) and Personal Factors as much as the presence of a health condition and impaired body functions and structures. Finally, impairment is seen not only in terms of reduced bodily functions, but also in terms of a person's inability to complete daily activities and/or to participate in important life roles. doi:10.1371/journal.pntd.0001366.g001 Need for access to low-cost hydrocelectomy to increase uptake.
Need for psychological and social interventions for hydrocele.

Bandyopadhyay 1996
Women and children's experiences and perceptions of LF Cultural practices strongly influenced health-seeking behaviour.
All women sought multiple methods for lymphoedema management. Clear study design with sampling and auditing process well described.
Author's theoretical position and role in research not acknowledged, could bias theory development.
Investigation of health beliefs and perceptions necessary to assist planning of culturally relevant health programs.
Family-centred health strategies important for effective lymphoedema management.
Training local healers has potential to increase widespread community understanding of LF.

Grounded Theory
Open ended interviews (n = 28); focus groups (n = 28) To identify a) the factors that impact SC and b) the impact of disrupted SC for women with LF. from participation in domestic and work roles and was one of the more widely reported causes of lack of income and employment for people living with LF [19][20][21]. Sexual relationships. Hydrocele patients state that sexual function is affected by pain, penetration and erection problems, and a reduced desire for sex [22][23][24]. In one study, all hydrocele patients reported decreased sexual functioning, with complications increasing with hydrocele size [22]. Women with lymphoedema who experienced secondary infections also reported avoiding sexual intercourse due to fear of infecting others with LF [18]. Pain during acute attacks was reported to reduce the desire for sex for both genders.

Participation
Interpersonal relationships. The impact of LF on personal relationships and marriageability is significant. Many people marry before physical symptoms become apparent, as visible signs of the disease greatly reduce both men and women's ability to find a partner [23,25,26]. In countries where marriage prospects are based on social class, LF patients reported marrying below their class, which negatively impacted the family's social status [23]. Only one study reported that if a girl ''has many other good qualities…outshines the other and has charm'' then she can still be considered a suitable marriage partner [19].
Major life areas. Work roles are routinely interrupted by LF symptoms. Patients with hydrocele report significant difficulties completing work roles, with larger hydrocele preventing any work activity [25,27]. Hydrocele patients also stated that hard labour, farming, and cultivation jobs worsen their condition [22].
Women with lymphoedema reported adopting a sick role, as they were unable to continue work and other life roles [28]. Women reported that dependence on others dramatically altered, or brought an end to, personally valued social, family, and community roles.
Some children who displayed physical symptoms early in childhood have been reported to be deprived of schooling, as education was believed to be futile [19,29]. In many communities, it was reported that participation in community events such as church, weddings, funerals, graduations, and community meetings was difficult due to social stigma.

Environmental Factors
Attitudes. The most commonly reported experience reported throughout the literature was social stigma. Participants across many studies reported being publically teased and taunted about  Figure 2 is an adaptation of the original ICF model [13] outlined in Figure 1. This model shows that the impact of LF is dependent on the interaction of a number of domains within the ICF. The impact of LF is dependent on the impact of the disease on body functions and structures and the level of impairment present. However, the impact of LF is also dependent on the person's environment, which can either facilitate good health (i.e., presence of LF programs within the community) or create a barrier to good health (i.e., the presence of social stigma within the community that prevents people with LF from accessing proper treatment). The impact of LF is seen also in terms of how the disease prevents people from completing daily activities and from participating in major life roles and community events. Finally, LF impact is influenced by personal factors such as poverty, gender, and age. This model shows how these elements (Body Function and Structure, Activity and Participation, Environment and Personal Factors) interact to determine the impact of LF for an individual living with the disease. Hence, LF programs that target solely the body structures and functions level only address one domain and do not respond to other factors that influence the overall impact of LF for a person. Interventions that also address environmental barriers, support re-engagement within daily activities and community participation, and respond to personal needs are theorised to have the greatest impact on the experience of LF for an individual. doi:10.1371/journal.pntd.0001366.g002 www.plosntds.org physical impairment [29,30]. Stigma appears to affect members of every social class, and participants believe it is often due to others' misunderstanding of the cause of LF and fear of contagion [19,28]. Being avoided by others is a common theme for many participants across the studies [18,[27][28][29]31]. Almost every study described how stigma pervaded all areas of public life for LF sufferers and was felt from families, school and health systems, and within the broader community.
Services, systems, and policies. Many participants expressed frustration regarding access to health services. Participants reported prolonged attempts to seek treatment through both local healers and health services, most at considerable expense [32]. Cost of service was reported as a barrier, often leading to ineffective home remedies [21]. Many participants reported ineffective treatments (scarification, bleeding, and amputations) that worsened their condition [24,32]. In one study, participants who had visited dermatologists trained in simple lymphoedema management were able to describe the cause of lymphoedema and the techniques required to care for their limb [32]. However, most participants within the studies who sought multiple health services did not understand the cause or treatment for LF, indicating that LF awareness is limited within local health services [18,25]. Participants reported a need for patient support groups and education about the disease (pamphlets, videos, and home visits) [19,28]. A fear of being identified as an LF patient was reported to prevent many from accessing LF-specific services [21], and many only sought assistance once symptoms significantly impacted work activities [21].
In one study, institutional stigma within the health system was reported where LF patients were being rejected by health services if they had severe physical disfigurement [29]. Institutional stigma was also found to occur within the education system, with reports that schools would not accept some children due to fear of contagion [19,29].

Personal Factors
Poverty. Throughout the studies, poverty is described as a great personal concern for LF patients. Participants revealed that poverty greatly impedes their ability to seek and access health care [21,24]. Poorer people were more likely to delay seeking assistance due to the cost of the appointment, treatment, and lost days of work [21]. Even when free medication was provided, the cost of travel and lost time from work prevented people from accessing medication. One study reported that many people with LF live in poorer areas that are more prone to vector breeding grounds and work in unhygienic conditions, placing them at risk of infection and lesions [21].

Psychological Impact
Without exception, people within the studies reported psychological issues that they directly related to living with their disability. Stress, frustration, and anxiety were commonly reported by participants [17,26,29]. In one study, fear and distress was felt strongest in the earlier stages of the disease as the disability began to effect daily life [28].
Poor self-esteem and embarrassment were commonly reported within the studies [18,19,28]. Participants reported feeling depressed by their social, economic, and physical situations, which were all worsened by the presence of LF-related disability [18,29,33]. Person's studies with women with lymphoedema reveal many women experience a pervading sense of loss of their formal lives [28,29].

Discussion
The aim of this paper was to review and critique the qualitative research on the experiences of people living with LF-related disability. Whilst this review has provided useful insight regarding the impact of LF on the daily lives of its sufferers, methodological limitations of the research body is a concern. There is an urgent need for methodologically sound social science research into LF. As with other neglected tropical disease programs, inadequate social research limits the political willingness to implement morbidity management strategies effectively [34,35]. Whilst MDA programs are being finished in many countries, the story of people living with LF is only beginning to be told.
This review highlights the complexities of daily life faced by people living with LF-related disability. Conceptualized within the ICF model of health, LF-related disability impairs all domains of function and health, resulting in complex interactions between the environment, body function and structures, personal factors, activity, and participation (see Figure 2). These affect the individual, their family, and their community. It is clear that interventions for LF need to expand beyond those that address only the physical impact of LF and address psychosocial impacts of the disease, a finding that is supported by other studies [36][37][38].
The current GPELF plan states that morbidity management is a priority for 2010-2020, with the following three strategies: 1. Developing guidelines for training modules based on most recent research 2. Developing simple, standardised metrics for morbidity management 3. Improving the integration of lymphoedema care into health systems [8] The GPELF suggests that programs record the number of people trained in lymphoedema management, number of surgeries performed, and number of patients treated. These reporting priorities continue to reflect a purely medical model of health [39]. Reporting on the number of patients who are actively maintaining self care activities, the number of patients who have seen a reduction in ADL attacks, or the number of patients who had no new disability/had reduced lymphoedema would be more useful outcome measures. Success in increasing patient independence and participation in their communities could also be measured by the number of patient support groups conducted, income generation activities conducted, or patients returning to work/school roles.
The GPELF could learn from the International Federation of Anti-Leprosy Associations (ILEP) Annual Project Report Form, which requires reporting on not only medical interventions, but on the type of rehabilitation programs (self care, support groups, and income generation activities) and number of patients who did not report any new disability [40]. Their programs report yearly on support at the patient (surgery, training, etc.), programme (training, health education, etc.), and rehabilitation (self-help groups) levels [41]. Similar reporting by GPELF would provide evidence of the outcomes within the second pillar globally.
The GPELF's third strategy to integrate greater lymphoedema care within the health system reflects a Western model of health delivery that may not fit within many LF-endemic regions. A focus on lymphoedema management for health services that still do not have basic knowledge on the cause and treatment of LF will not relieve LF patients of the social stigma, psychological burden, activity limitations, and participation restrictions they face, particularly those in later stages of lymphoedema.
A health care model that could be explored for LF is community-based rehabilitation (CBR). CBR is communitydriven, low-cost health care that promotes social inclusion for people with disabilities (PWD) [42]. Support given by CBR workers varies; however, it can include exercise and self care education, access to mobility aids, vocational training, support to re-engage in activities of daily living, psychological support, and health promotion activities [43]. Such programs are highly relevant for needs of LF patients found in this review. Whilst there have been examples of the use of community health workers for hygiene management [44,45] and integrating LF strategies into community programs [46,47], a strategic approach to engaging with CBR programs for LF management has not been investigated. If the GPELF is planning to develop training manuals, an LF CBR manual similar to that used for leprosy [48] could go a long way to improving local knowledge of the disease and allow LF patients to readily access existing services.

Conclusions
This paper aimed to review the qualitative literature on the experience of LF-related disability. The findings highlight the complexity of LF-related disability and its impact on the daily activities, participation, and psychological health of people with LF. This review has shown that there is a scarcity of high quality research into LF patient's experiences, indicating that there are many gaps in knowledge remaining. Regardless of the successes of the GPELF programme, millions of people remain burdened by LF-related disability. Whilst there is momentum in the claims of MDA programmes being successful in ''eliminating'' the disease, millions of people remain impoverished, psychologically damaged, and unable to complete daily activities of necessity. The language that WHO and the GPELF utilize over the coming years is crucial. Claims of widespread ''successful elimination programmes'' misrepresent the experiences of those already living with LF-related disability and make it increasingly difficult to advocate for morbidity management programmes.