Medicine
Permanent URI for this communityhttp://repository.kln.ac.lk/handle/123456789/12
This repository contains the published and unpublished research of the Faculty of Medicine by the staff members of the faculty
Browse
126 results
Search Results
Item Lymphatic filariases and soil-transmitted helminthiases in Sri Lanka: the challenge of eliminating residual pockets of transmission(The Royal Society, 2023) Chandrasena, T.G.A.N.; Gunaratna, I.E.; Ediriweera, D.; de Silva, N.R.Sri Lanka has successfully met the challenge of controlling both lymphatic filariasis (LF) and soil-transmitted helminthiases (STH) as public health problems. The primary public health strategy for combatting both conditions has been preventive chemotherapy. The national programme for the elimination of LF implemented five annual rounds of mass chemotherapy in the endemic districts from 2002 to 2006 using a combination of diethylcarbamazine and albendazole. The overall microfilaria rate declined from 0.21% in 2001 before the mass chemotherapy, to 0.06% in 2016, at declaration of elimination of LF as a public health problem by the World Health Organization. Currently Sri Lanka is in the phase of post-validation surveillance. Achieving control of STH has been more difficult. Mass deworming programmes have been implemented for nearly a century, and national-level surveys reported prevalence rates declining from 6.9% in 2003 to 1% in 2017. However, neither of these infections has been completely eliminated. A situation analysis indicates continued transmission of both among high-risk communities. This paper explores the reasons for persistence of transmission of both LF and STH in residual pockets and the measures that are required to achieve long-term control, or perhaps even interrupt transmission in Sri Lanka. This article is part of the theme issue 'Challenges and opportunities in the fight against neglected tropical diseases: a decade from the London Declaration on NTDs'.Item Lymphatic filariasis in the Southeast Asian region; status and control options.(CABI Publishing, 2020) Chandrasena, T.G.A.N.; Premaratna, R.; Mallawarachchi, C.H.; Gunaratna, D.G.A.M.; de Silva, N.R.ABSTRACT: The Global Program to Eliminate Lymphatic Filariasis (GPELF) was launched in year 2000 by the World Health Organization (WHO) with the goal set for elimination by 2020. Over half the global disease burden lies in the Southeast Asian region (SEAR). The preventive chemotherapy (PC) programme has been initiated in all the WHO SEAR member states with varying levels of progress. Maldives, Sri Lanka and Thailand have achieved the goal of elimination as a public health problem (EPHP) within the stipulated period with Bangladesh working towards validation in 2021. Both Sri Lanka and Thailand are continuing with post-validation surveillance combined with selective treatment, striving for zero transmission in-parallel with the morbidity management and disability prevention program (MMDP). Timor-Leste appears close to reaching critical transmission thresholds with 100% coverage and triple therapy in the last round of PC. Data on MMDP activities are insufficient to comment on reaching EPHP status. PC coverage and country reports indicate ongoing transmission in Nepal, Myanmar, Indonesia and India requiring further rounds of PC. The PELF has made considerable progress in the SEAR towards elimination but there still remain significant transmission and disease burden in the highly populated countries in SEAR.Item Progress in the prevention and control of schistosomiasis and soil-transmitted helminthiasis(Societa Italiana di Medicina Tropicale, 2002) Albonico, M.; Engels, D.; Montresor, A.; Cromptons, D.W.T.; de Silva, N.R.; Savioli, L.ABSTRACT: In the last two decades important progress have been made in the understanding the epidemiology and the disease burden of schistosomiasis and soil-transmitted nematodes infection. In addition, practical tools for disease control have been developed and a strategy for the prevention and control of morbidy of schistosomaisis and soil-transmitted nematodes infection has been endorsed by the World Health Organization. This paper presents the recent progress in the prevention and control of these infections: the estimates of chronic and subtle morbidity in high risk groups and the evidence that these chronic and severe sequelae of infections can be reversed by appropriate treatment; the use of anthelminthic drugs during pregnancy and lactation; the relevance to control morbidity due to these infections also in pre-school children; the efficacy of anthelminthic drugs and the possible threat of drug resistance; price, quality and accessibility of treatment by delivering drugs through the school system and ways of reaching also non enrolled school-age children. Finally, the strategy, targets and recommendations of the World Health Organization for the control of schistosomiasis and soil-transmitted nematodes infection are described.Item Lapses of professionalism occurring among Sri Lankan medical students: How should they be remediated?(Sri Lanka Medical Association., 2019) Ellawala, A.T.; Chandratilake, M.N.; de Silva, N.R.INTRODUCTION & OBJECTIVES: Early recognition and correction of lapses of professionalism occurring during 'the undergraduate period is vital. This study aimed to explore the lapses of professionalism occurring among local medical students and identify appropriate remedial measures. METHODS: The study was conducted in two phases. In Phase I, in-depth interviews and focus group discussions were conducted with medical teachers, clinicians, deans, students, nurses and patients (n= 129) to explore lapses they had witnessed. Conversations were audio-recorded, transcribed and analysed inductively. Description by multiple groups was considered an indicator of prevalence of a behaviour. In Phase II, a consensus conference with medical teachers, clinicians, deans and students (n=3 I), was conducted to achieve consensus on remediation strategies for identified lapses occurring as a first-time offence or a repeated behaviour pattern. Degree of consensus was based on modal distribution of responses. RESULTS: In Phase I, over 100 types of misconduct were described. The most common behaviours included, 'not doing allocated ward work', 'not contributing to group work' and 'several students examining a patient at the same time'. In Phase II, it was possible to achieve an acceptable level of agreement (50% or higher consensus) regarding remediation strategies for over 70% of the items, including almost all lapses identified as most common. Strategies ranged from 'ignore' to 'expulsion' and included measures such as discussion with peers, remedial work and counselling. CONCLUSION: Sri Lankan medical students exhibit a wide range of professionalism lapses of varying severity. The value of correcting such behaviour in a standardized manner is recognised.Item Intestinal Nematodes: Ascariasis(Elsevier, 2020) Bundy, D.A.P.; de Silva, N.R.; Appleby, L.J.; Brooker, S.J.Ascariasis is the most prevalent human helminth infection, with an estimated 819 million infections worldwide. Transmission primarily occurs in warm, tropical climates that lack water and sanitation facilities and have poor hygiene. Worms inhabit the small intestine, and morbidity is related to worm burden. A small proportion of the infected population harbors the majority of worms, with intense infection most common in school-age children, and intensity and prevalence declining to a low level throughout adulthood. School-age children are therefore the targets for school-based community control efforts in large-scale treatment campaigns. Light infections can affect growth and development, whereas, due to the size of the worms, heavier worm burdens can result in intestinal obstruction, particularly in young children. Treatment with mebendazole or albendazole is efficacious, with cure rates of >90% commonly achieved.Item Introduction of Recombinase Polymerase Amplification assay based mobile suitcase laboratory as a point of need tool to diagnose cutaneous leishmaniasis in Sri Lanka(Sri Lanka Medical Association, 2018) Gunaratna, G.P.S.; Ranasinghe, P. H. K. I. S.; Manamperi, A.; Pathirana, N.; Pathirana, H.; Wickremasinghe, R.; de Silva, N.R.; Sooriyarachchi, M.; Ahmed, A.E.W.INTRODUCTION AND OBJECTIVES: Cutaneous leishmaniasis (CL) caused by the vector-borne protozoan parasite is now endemic in Sri Lanka. Microscopy of Giemsa stained slit skin smears (SSS), lesion aspirates or scrapings for the presence of amastigotes, is widely used for laboratory confirmation of CL, although the reported sensitivity is low. Facilities for more sensitive culture and molecular techniques are available only in reference laboratories. A newly developed, Recombinase Polymerase Amplification (RPA) assay based Mobile Suitcase Laboratory (MSL) is a promising, molecular point of care test with high sensitivity and specificity for diagnosis of both post-kala• azar dermal leishmaniasis and visceral leishmaniasis. Objective was to assess RPA based MSL as a point of need tool to diagnose CL in Sri Lanka.METHODS: Twenty seven army personnel at Mullaitivu Army camp clinically suspected of having CL were recruited for this pilot study. Two slit skin smears and two punch biopsy specimens were obtained from each of them. Slit skin smears were stained with Giemsa in the field and examined for the presence of amastigotes and RPA was carried out at the point of collection. PCR was performed at the Parasitology Department, Sri Jayewardenepura University. RESULTS: Fifteen patients were confirmed by PCR as having CL and 14 of them were also positive by RPA based MSL conducted in the field (93.33% sensitivity). Only 3/15 were positive with microscopy of SSS (20% sensitivity). CONCLUSION: This pilot study shows RPA based MSL as a promising tool to diagnose CL at point of need.Item Detection of a case of Brugian Filariasis from Anuradhapura, a non-endemic district of Sri Lanka(Sri Lanka Medical Association, 2018) Mallawarachchi, C.H.; Gunaratne, I.E.; Ekanayaka, G.M.G.A.C.; Mallawarachchi, S.M.N.S.M.; Chandrasena, T.G.A.N.; Mendis, D.; de Silva, N.R.INTRODUCTION AND OBJECTIVES: In 2016, the WHO declared that lymphatic filariasis was no longer a public health problem in Sri Lanka. However low-grade persistence of bancroftian filariasis continues in all three endemic provinces, while brugian filariasis has re-emerged. The periodicity pattern of the re-emerged Brugia spp. suggests zoonotic origin. A canine survey done in the district of Anuradhapura found a moderately high prevalence (28.2%) of B. malayi infections in the Thirappane MOH area. Objective of the study was to investigate the threat of zoonotic B.malayi infections to humans in the Thirappane MOH area. METHODS: A cross sectional survey was done among all consenting residents of three randomly selected areas representing the three PHI areas of the Thirappane MOH. Residents were screened between 8.00 pm and 12.00 pm using night blood smears (NBS) and Brugia rapid test (BRT) for presence of anti-Brugia IgG4 antibodies. BRT was done selectively. Ethical and administrative clearance was obtained prior to the survey. RESULTS: A total of 752 individuals were screened by NBS; 176 of them were also screened by BRT. 193, 208 and 351 NBSs were done respectively in Thirappane, Galkulama and Mooriyankadawala PHI areas. One individual, a 25-year-old long-term resident of Mooriyankadawala PHI area was positive for Brugia spp. microfilariae by NBS and by BRT. The microfilariae exhibited nocturnal sub-periodicity. CONCLUSION: Transmission of brugian filariasis appears to occur even outside the traditional endemic belt. The presence of canine reservoirs of infection and water bodies with aquatic vegetation probably favour transmission by Mansonia spp. vector mosquitoes in the study area.Item Intestinal nematodes that migrate through lungs (Ascariasis)(WB Saunders Company, 2000) de Silva, N.R.; Bundy, D.A.P.Item Soil-transmitted helminth infections in Sri Lanka(Federation of Asian Parasitologists, AAA Committee, 2005) de Silva, N.R.No abstract availableItem Effectiveness of mebendazole and health education in control of pinworm infection among children living in low income settlements(Sri Lanka Medical Association, 2017) Kumarendran, B.; Pathmeswaran, A.; de Silva, N.R.INTRODUCTION & OBJECTIVES: We aimed to evaluate the effectiveness of mebendazole (MBZ) mass treatment and health education in reducing reinfection with pinworm among children living in low income settlements (LIS). METHODS: A factorial cluster-randomized, controlled trial was conducted during January to May 2014, to compare the effectiveness of MBZ 100mg for positive cases versus mass treatment, and routine versus special health education. 1257 children aged 3-7 years, from 48 clusters of LIS in the Colombo Municipal Council area, were selected using cluster sampling. Perianal cellophane adhesive swabs (CAS) were examined for pinworm eggs. About 2-3 weeks after collection of the first sample (CAS1), depending on the intervention arm, eligible participants were given MBZ. Second sample (CAS2) was collected a week after administration of the first dose (MBZ1). Second dose (MBZ2) was given two weeks after MBZ1. Third sample (CAS3) was collected a week after MBZ2, and a fourth sample (CAS4) was collected 12 weeks after MBZ2. RESULTS: Sample collection rate was 94%, 80%, 75% and 73%, for CAS1, CAS2, CAS3 and CAS4 respectively. Overall egg positivity reduced from 42.5% to 10% following MBZ1, and to 6.8% following MBZ2, but increased to 29.3% at 12 weeks following MBZ2. In logistic regression, reinfection rate at 12 weeks after MBZ2 (i.e. those who were CAS3 negative but CAS4 positive) was associated with baseline pinworm egg positivity (OR=1.2) and BMI for age Z score (OR=0.96), but not with intervention arm. CONCLUSION: MBZ is effective in reducing pinworm egg positivity, but re-infection is common.