CHAPTER 2: RATIONALE AND OBJECTIVES OF THE THESIS
2.1 Rationale of the research
As stated in the previous chapter, Kala-azar is an important public health problem in Nepal and the country p articipates in a r egional collaborative ef fort to e liminate VL from t he Indian subcontinent. To control, or even elimination of VL to be successful, it will require number of considerable efforts that needs to be implemented over the longer term. Effective control of VL will depend on the integration of public health interventions and research evidences that need to be translated into a ction. However, t he s carcity of ad equate d ata, b oth ep idemiological an d economic, c ontributes t o t he l ow a ttention a nd p riority given b y n ational c ontrol pr ogrammes and international donors also. At the outset of my thesis work, there are number of important knowledge gaps that are particular interest to the elimination initiative in Nepal (figure 2.1).
1. There was little community-based epidemiological information on Leishmania infections and disease available from Nepal except for two small surveys from eastern Nepal (Koirala et al. 1998;2004; Schenkel et al. 2006). Lack of epidemiological data is also considered as a major handicap in the proper implementation of the control programme (Bista 1998).
2. VL is a r ural d isease an d associated w ith precarious hous ing conditions (mud pl astered house) and the environment (humid soil and organic debris) of the poor communities. The proliferation of the vector is enhanced by poor housing conditions which provide excellent breeding sites for sandflies and increased the risk of infection through the bite of vector or increased human-vector contact (Singh et al. 2010). More recently, questions were raised about possible urban transmission and it is becoming a p eri-urban disease. This should be verified and needs to be investigated.
3. VL is a disease of poverty affecting the poorest of the poor (Alvar et al. 2006; Boelaert et al. 2009) but l imited i nformation on the bur den of V L on affected hous eholds after t he intensified i mplementation of V L c ontrol e fforts. T here ar e few s tudies qua ntifying t he economic burden of VL on households conducted prior to the elimination initiative showed the profound impact of a VL episode on the socio-economic status of the household (Rijal et al. 2006; Meheus et al. 2006; Adhikari et al.2009). The median total expenditure by a patient on V L treatment was 1.2 t o 1.4 t imes the annual per capita income (WHO 2010).
After the intensified implementation of VL control efforts, the economic burden of VL on households could be expected to be reduced, but neither data nor monitoring existed.
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4. Miltefosine, the onl y oral d rug fo r V L, i s c urrently t he 1 st line th erapy in th e V L elimination programme of t he Indian s ubcontinent and s o f ar little a ttention is g iven to monitor the clinical outcomes and patient adherence (Hasker et al. 2010; Malaviya et al.
2011). Although m iltefosine s howed an ex cellent ef ficacy i n p hase t hree clinical tr ials (Sundar et al. 2002), a recent data indicate increased failure rates after a decade of use in Bihar, India (Sundar et al. 2012) and five years of use in Nepal (Rijal et al. 2013). Given the h igh p revalence o f gastrointestinal s ide effects o f m iltefosine ( >60%, S undar et al.
2012) on one h and and the relatively fast r esolution of clinical s ymptoms of V L on t he other, patient may lose their motivation to complete the 28 da ys of miltefosine treatment.
Therefore, treatment outcomes and patient compliance to treatment is a key factor worth monitoring. S o f ar, no f ormal e valuation of adherence t o M iltefosine has b een r eported from Nepal or from any other region.
5. Last but not least, there is a risk of re-emergence of VL if the issue of PKDL is ignored since PKDL patients could act as a reservoir of infection within the population (Zijlstra et al. 2003). No data on PKDL epidemiology and burden existed from Nepal.
Based on the above knowledge gaps, the following objectives for the thesis were derived.
2.2 Objectives General objective:
The m ain obj ective of t he thesis was t o provide evidence for more rational V L control to the ongoing elimination initiative in the Indian subcontinent in general and in Nepal in particular.
Specific objectives:
1. Describe the e pidemiology of Leishmania donovani infection a nd di sease in hi gh- transmission areas
2. Understand the risk factors for VL with regards to possible urban transmission 3. Assess the health seeking behavior and economic burden of VL on households.
4. Monitor the treatment outcomes and patient adherence to currently used anti-VL drugs.
5. Estimate the prevalence, risk and risk factors of PKDL in patients treated for VL.
Page Figure 2.1: Gaps of knowledge for VL elimination leading to the topics for PhD research
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2.3 References
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Adhikari SR, Maskay NM, Sharma BP (2009) Paying for hospital-based care of Kala-azar in Nepal: assessing catastrophic, impoverishment and economic consequences. Health Policy Plan 24, 129-139.
Alvar J, Yactayo S, Bern C (2006) Leishmaniasis and Poverty. Trends Parasitol 22, 552-557.
Bista MB (1998) National overview of kala-azar in Nepal. In: kala-azar in Nepal: principles, practice and public health perspectives (eds Bastola S, Karki P, Rijal S & Gautam A) EDCD/BPKIHS/WHO, Kathamandu, pp. 1-5.
Boelaert M, Meheus F, Sanchez A, Singh SP, Vanlerberghe V, Picado A, Meessen B, Sundar S (2009) The poorest of the poor: a poverty appraisal of households affected by visceral leishmaniasis in Bihar, India. Trop Med Int Health 14, 639-644.
Hasker E, Singh SP, Malaviya P et al. (2010) Management of visceral leishmaniasis in rural primary health care services in Bihar, India. Trop Med Int Health 15 suppl2, 55-62.
Malaviya P, Singh RP, Singh SP et al. (2011) Monitoring drug effectiveness in kala-azar in Bihar, India: cost and feasibility of periodic random surveys vs. a health service-based reporting system. Trop Med Int Health 16, 1159-1166.
Meheus F, Boelaert M, Baltussen R, Sundar S (2006) Costs of patient management of visceral leishmaniasis in Muzaffarpur, Bihar, India.Tropical Medicine and Internationl Health 11,1715-24.
Koirala S, Parija SC, Karki P, Das ML (1998) Knowledge, attitudes, and practices about kala- azar and its sandfly vector in rural communities of Nepal. Bull World Health Organ 76, 485-490.
Koirala S, Karki P, Das ML, Parija SC, Karki BMS (2004) Epidemiological study of kala-azar by direct agglutination test in two rural communities of eastern Nepal. Trop Med Int Health 9, 533-537.
Rijal S, Koirala S, Van der Stuyft P, Boelaert M (2006) The economic burden of visceral leishmaniasis for households in Nepal. Trans R Soc Trop Med Hyg 100, 838-841.
Rijal S, Ostyn B, Uranw S, et al. (2013) Increasing failure of Miltefosine in the treatment of Kala-azar in Nepal and the potential role of parasite drug resistance, re-infection, or non-compliance. Clin Infect Dis.2013 Jun;56(11):1530-8.
Schenkel K, Rijal S, Koirala S, Koirala S, Vanlerberghe V, Van der Stuyft P, Gramiccia M, Boelaert M (2006) Visceral leishmaniasis in southeastern Nepal: a cross-sectional
survey on Leishmani donovani infection and its risk factors. Trop Med Int Health 11, 1792-1799.
Singh SP, Hasker E, Picado A, Gidwani K, Malaviya P, Singh RP, Boelaert M, Sundar S (2010) Risk factors for visceral leishmaniasis in India: further evidence on the role of domestic animals. Tropical Medicine and International Health 15 Suppl2, 29-35.
Sundar S, Jha TK, Thakur CP et al. (2002) Oral miltefosine for Indian visceral leishmaniasis.
N.Engl.J.Med. 347, p 1739-1746.
Sundar S, Singh A, Rai M et al. (2012) Efficacy of Miltefosine in the Treatment of Visceral Leishmaniasis in India After a Decade of Use.Clin Infec Dis. May 31.
World Health Organization (2010) Control of leishmaniasis. World Health Organ Tech Rep Ser 949:186.
Zijlstra EE, Musa AM, Khalil EAG, El Hassan AM (2003) Post-kala-azar dermal leishmaniasis. Lancet Infectious Disease 3; 87-97.
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