Browsing by Author "Abeysundara, S."

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Chloroquine resistant falciparum malaria among security forces personnel in the Northern Province of Sri Lanka
(Sri Lanka Medical Association, 2004) Hapuarachchi, H.A.C.; Dayanath, M.Y.D.; Abeysundara, S.; Bandara, K.B.A.T.; Abeyewickreme, W.; de Silva, N.R.
OBJECTIVE: To determine the occurrence and species distribution of malaria and the extent of chloroquine resistance among security forcespersonnel in a selected region of the Northern Province of Sri Lanka. DESIGN: A descriptive study. SETTING: Mannar District in the Northern Province. METHODS: Nine hundred and seventy five security personnel were screened for malaria by microscopy. Those who were positive were treated withchloroquine and were subjected to 28 day in vivo assay to determine chloroquine resistance. In vitro microtest assay was performed to determine the response of Plasmodium falciparum isolates to chloroquine in vitro. RESULTS: Of the 975 personnel screened, 181 (18.6%) were positive for malaria. P. falciparum was the predominant species (n = 125; 69.1%). The rest were due to P. vivax (n = 42; 23.2%) and mixed infections (n = 14; 7.7%). This was an inversion of the usual species distribution pattern in the country. In vivo assay revealed 38 (53.5%) P. falciparum infections as chloroquine resistant. Fifteen of 23 (65.2%) P. falciparum isolates showed evidence of resistance in vitro. None of the P. vivax infections showed evidence of chloroquine resistance. There was no significant difference in the severity of clinical disease between chloroquine resistant and sensitive infections at first presentation. Recrudescent P. falciparum infections had significantly lower mean parasite densities as well as lower clinical scores at recrudescence than at first presentation. CONCLUSION: Results demonstrate the high prevalence of malaria and chloroquine resistance in the study area and explains several contributory factors for this. There is an urgent need to review antimalarial drug policies in Sri Lanka
Comparison of five DNA extraction methods from human blood for the detection of Wuchereria bancrofti by polymerase chain reaction assays
(Sri Lanka Association for the Advancement of Science, 2008) Wijegunawardana, N.D.A.D.; Gunawardene, Y.I.N.S.; Manamperi, A.; Hapuarachchi, H.A.C.; Gunawardena, N.K.; Abeysundara, S.; Abeyewickreme, W.
Introduction: Lymphatic filariasis (Lf) is the second most common vector-borne disease globally. Approximately 90% of global burden of Lf is caused by Wuchereria bancrofti. W. bancrofti is routinely diagnosed by morphological identification of microfilariae (Mf) by microscopy which is a labour intense, low sensitive and time consuming method. Detection of W. bancrofti Deoxyribonucleic acid (DNA) using polymerase chain reaction (PCR) technique has become popular today, because of its high sensitivity and specificity. The overall success of the PCR strategy in detecting a filarial parasite in human blood varies between sample preparation methods. The objective of this study was to compare five DNA extraction methods (Lysis + centrifugation, Chelex method, Mf pellet method, Q1Aamp DNA Mini Kit commercial system, and Phenol-chloroform) with regard to duration of completion, labor involvement and PCR analytical sensitivity in-relation to DNA quality and quantity for the detection of W. bancrofti in human blood. Five blood samples positive for mf of W. bancrofti were tested for each DNA extraction method and were compared with respect to the sensitivity, time and quality/quantity of DNA and also by PCR analysis. Of the 5 methods tested, Mf pellet method was found to be the most simple and effective technique for the isolation of W. bancrofti Mf in human blood. This method was quick (15 min to complete), simple (5 min of manual labor), and very economical. It does not require any organic solvents, and the entire extraction procedure uses only two steps requiring supernatant transfer between tubes, hence minimizing the possibility of cross-contamination. Moreover, the PCR analytical sensitivity of the Mf pellet method was comparable to that of the commercial kit used. No PCR inhibitors were detected, independently of Mf count in the blood. Same method (optimal DNA extraction method) can be also used for the detection of parasite DNA from the field collected Mf positive mosquitoes using a PCR. Therefore, we recommend the Mf pellet method for processing large numbers of blood samples in community surveys aimed at determining the prevalence of W. bancrofti infection.
Evaluating the Antibiotic Properties of Bee Honey as Against Common Pathogenic and Antibiotic Resistant Bacteria Found in Wound Infections
(International Postgraduate Research Conference 2019, Faculty of Graduate Studies, University of Kelaniya, Sri Lanka, 2019) Wijesooriya, L.I.; Abeysundara, S.
Introduction: Antibiotics have largely been effective in treating bacterial infections. However, inappropriate use of antibiotics has led to extensive antibiotic resistance globally. In addition, no new classes of antibiotics are available to counter the dramatic rise of antibiotic resistance. This has led to unorthodox methods in treating antibiotic-resistant bacterial infections. One of these methods is the use of bee honey, which has been used since ancient times. Objective: The objective of the present study was to determine the effectiveness of bee honey against common pathogenic bacteria in wound infections Methodology: Common bacterial wound pathogens viz. Streptococcus pyogenes, Streptococcus agalactiae, methicillin resistant Staphylococcus aureus (MRSA), Escherichia coli (extended-spectrum beta-lactamases producing), Klebsiella pneumoniae, Acinetobacter spp, and Enterococcus spp were selected for the study. Suspensions of 0.5 McFarland strength of S. pyogenes was streaked on blood agar and the others were streaked on Muller Hinton agar. Sterile, 1"x1" size, single gauze layer, soaked with commercially available pure Bee honey (100%) was placed on the center of each inoculated plate and incubated overnight at 37 oC. On following day, each piece of gauze was removed aseptically. Presence of live bacteria from the site where gauze was removed from each plate was checked by streaking on blood agar. The same place where gauze was removed was repositioned with new, sterile gauze layer soaked with bee honey. All plates were incubated at 37 oC. Same procedure was continued until no growth was observed. Control tests were done in parallel using same sized gauze without bee honey. Sterility of bee honey was previously confirmed by inoculation on blood agar. The experiment was repeated two times. Results: Following repeat applications of bee honey, there was no bacterial growth from plates inoculated with S. pyogenes and S. agalactiae after two applications, Acinetobacter spp - three, MRSA – four, K. pneumoniae, E.coli and Enterococcus spp - five and Pseudomonas spp – six applications. There was no inhibition of bacterial growth in the control plates. Conclusion: Antibacterial effect of bee honey against S. pyogenes and S. agalactiae was highly satisfactory with clearance of the organisms with only two applications whereas it was satisfactory against MRSA, Acinetobacter spp. Klebsiella spp, E.coli and Enterococcus spp and longest duration of application was needed for Pseudomonas spp. These in vitro anti-bacterial test results suggest that bee honey has effective antibacterial property against common wound pathogens with varying duration of application
Evidence for emerging sulfadoxine-pyrimethamine resistance of Plasmodium falciparum isolated in the Northern Province of Sri Lanka
(Sri Lanka Association for the Advancement of Science, 2005) Hapuarachchi, H.A.C.; Dayanath, M.Y.D.; Abeysundara, S.; Bandara, K.B.A.T.; Abeyewickreme, W.; de Silva, N.R.
Genetic evidence of emerging sulfadoxine-pyrimethamine resistance of Plassmodium falciparum isolates in an operational area in the Northern Province of Sri Lanka
(Sri Lanka Association for the Advancement of Science, 2004) Hapuarachchi, H.A.C.; Dayanath, M.Y.D.; Abeysundara, S.; Bandara, K.B.A.T.; Abeyewickreme, W.; de Silva, N.R.
K76T point mutation of chloroquine resistance transporter gene: Is it a potential molecular marker for chloroquine resistance in Sri Lankan Plasmodium falciparum isolates?
(Sri Lanka Association for the Advancement of Science, 2007) Hapuarachchi, H.A.C.; Dayanath, M.Y.D.; Abeysundara, S.; Manamperi, A.; Abeyewickreme, W.; de Silva, N.R.
Current evidence suggests that K76T mutation of chloroquine resistance transporter (Pfcrt) gene may be used as a molecular marker for chloroquine (CQ) resistance of P. falciparum. This study was carried out to determine the frequency of K76T mutation of Pfcrt gene in Sri Lankan P. falciparum isolates collected from Mannar district in the Northern Province. Mutation patterns were compared with in vitro and in vivo CQ failure rates for this parasite population to analyze its association with resistance to CQ and to calculate the genotype-resistance (GRI) and genotype-failure (GFI) indices for K76T mutation. P. falciparum DNA was extracted from dried blood spots using a QiaAmp DNA Blood Mini Kit. Mutation patterns at 76 codon of Pfcrt of field isolates were detected using a polymerase chain reaction - restriction fragment length polymorphism assay. Parasite isolates were categorized into wild (sensitive) and mutant (resistant) types based on the banding patterns of digested products on 2% agarose gels. GRI and GFI indices were calculated for this parasite population. Of 38 CQ resistant isolates, 86.8% (N = 33) showed the mutant allele (K76T) at codon 76 of Pfcrt. There was a statistically significant association between the presence of K76T mutation and in vivo resistance to CQ (x2 = 5.11, p = 0.02). Of 33 sensitive isolates, 39.4% (N = 20) possessed the wild type allele at the same codon position. The calculated GRI and GFI indices were 1.13 and 1.38 respectively for this area. Even though results show a statistically significant association between the presence of K76T allele and CQ treatment failure of P. falciparum isolates in the study population, its mere presence alone does not seem to correlate with resistance to CQ. Therefore, mutations at other codons of Pfcrt shown to accompany K76T mutation as well as those in P. falciparum multi drug resistance 1 (Pfmdr1) gene need to be analyzed to determine whether other mutations play a role together with K76T in clinically resistant Sri Lankan parasite isolates. More studies are required to validate the calculated GRI and GFI values, which may be used to predict the therapeutic failure of CQ in a particular area in Sri Lanka in the future. Acknowledgement: National Science Foundation Research grant SIDA/2005/BT/03 and by the IAEA TC Project SRL 06/028
A Mixed infection of Plasmodium falciparum and Plasmodium malariae: the first report of a Plasmodium malariae infection after 37 years of its absence in Sri Lanka
(2008) Hapuarachchi, H.A.C.; Abeysundara, S.; Gunawardena, N.K.; Manamperi, A.; Senevirathne, M. P.; Leemingsawat, S.; Chavalitshewinkoon-petmitr, P.; de Silva, N.R.; Abeyewickreme, W.
Malaria has been endemic in Sti Lanka for several centuries. Currently, only Plasmodium falciparum and P. vivax are present in the country. P. malariae infections have not .been reported in Sri Lanka since 1969. The objective is to determine the presence of malaria species in a patient returned from Malawi. The clinical history of intermittent high fever for 2 weeks accompanied by severe headache, myalgia, arthralgia, vomitimg, loss of appetite and backache with ictetus and mild hepatosplenomegaly suggested malaria in this 51 year old patient. Apart from the basic biochemical investigations, presence of malarial species was determined by light microscopy and confirmed by Real-Time Polymerase Chain Reaction (PCR) technology. Biochemical investigations showed a high serum bilirubin (4.8 mg/di) and liver enzyme (SGOT = >125 units, SGPT = >250 units) levels. Serum haemoglobin level (12.8 g%) was normal. Except for the presence of ptoteinuria (albumin = ++), bile (+) and red blood corpuscles (RBC) in his urine, renal functions were normal. Microscopical examination of Giemsa stained thin and thick blood smears showed an asexual parasite density of 120,000 per ul of blood. Infected RBCs were not enlarged, The presence of double-chromatin and applique form trophozoites, occasionally invading multiple RBCs suggested P. falciparum infection. In addition, there were characteristic band form trophozoites of P. malariae. Real-Time PCR protocol confirmed the presence of both P. falciparum and P. malariae in this patient. This is the first case of P. malariae reported in Sri Lanka after 4 decades, though the infection had been acquired from Malawi. Clinical and biochemical evidence indicated liver dysfunction and a transient glomerulonephritis, both of which subsided after treatment with quinine. This case report emphasizes the need of physicians to be more vigilant about the presence of malaria among immigrants, despite the drastic reduction of malaria in the country in recent years. Hence, this report highlights the importance of a proper programme in Sri Lanka to screen immigrants for infectious diseases.
Molecular markers of chloroquine resistance in Plasmodium falciparum in Sri Lanka:frequency before revision of the antimalarial drug policy
(Academic Press, 2009) Hapuarachchi, H.A.C.; Abeysundara, S.; Dayanath, M.Y.D.; Manamperi, A.; Abeyewickreme, W.; de Silva, N.R.
No Abstract Available
Night blood survey of a selected high-risk population for lymphatic filariasis
(Sri Lanka Association for the Advancement of Science, 2007) Wijegunawardana, N.D.A.D.; Gunawardene, Y.I.N.S.; Abeyewickreme, W.; Gunawardena, N.K.; Hapuarachchi, H.A.C.; Abeysundara, S.
Human infection with Wuchereria bancrofti causes a disabling parasitic disease known as lymphatic filariasis, which is a major public health and socio-economic problem in many parts of the world. Little is known about the prevalence of filariasis among high-risk populations for filariasis. Objective of this study was to determine such prevalence of lymphatic filariasis among Mahara prison inmates whom the Anti Filaria Campaign (AFC) has identified as a high-risk group. All inmates of Mahara Prison were screened for Microfilariae (Mf) except those in special cells, by night blood film microscopy to determine the prevalence of infection from February to May 2007. All inmates were males of greater than 15 years. Of the 423 inmates screened, 15 were positive for Mf, giving a Mf positive rate of 3.55% in the study population and a mean Mf density of 5 Mf/60 æl blood, ranging between 4 to 9.2 Mf /60 æl of blood with a standard deviation of 2.49. The highest number of infected inmates was residents of Colombo and Gampaha districts where transmission is currently taking place. This is one of the few studies undertaken to date to determine the prevalence of bancroftian filariasis among inmates of a prison, a neglected population in Sri Lanka. This study indicates that the Mf rate of bancroftian filariasis in this study population is far greater than the 0.18% currently reported in the country. Therefore, an intensive programme is recommended to contain the spread of infection within this study population. For this, a proper screening programme combined with antifilarial treatment and vector control programme is urgently required. Acknowledgements: Authors wish to acknowledge the financial assistance received from WHO/SEARO/TDR (grant no. SN 1152) and University of Kelaniya (Research grant no. RP/03/04/06/01/2006). Authors wish to thank Dr. Ravi Mudaliage, Senior Medical Officer, Prison's Hospital, Mahara, Ragama for his support and encouragement during field study activities. Authors also wish to thank Mr. M. Y. D. Dayanath, Ms. N.M. Ashoka Malanie, Mr. M.I.M.Peris, Mr. Y.L.Rassapana and other staff members of the Molecular Medicine Unit and Department of Parasitology, Faculty of Medicne, University of Kelaniya, Ragama for their assistance
Point mutations in the dihydrofolate reductase and dihydropteroate synthase genes of Plasmodium falciparum and resistance to sulfadoxine-pyrimethamine in Sri Lanka
(American Society of Tropical Medicine and Hygiene, 2006) Hapuarachchi, H.A.C.; Dayanath, M.Y.D.; Bandara, K.B.A.T.; Abeysundara, S.; Abeyewickreme, W.; de Silva, N.R.; Hunt, S.Y.; Sibley, C.H.
Sulfadoxine-pyrimethamine (SP) is the second-line treatment for Plasmodium falciparum malaria in Sri Lanka. Resistance to SP is caused by point mutations in the dihydrofolate reductase (Pf-dhfr) and dihydropteroate synthase (Pf-dhps) genes of P. falciparum. We determined the genotype of Pf-dhfr and Pf-dhps and the clinical response to SP in 30 field isolates of P. falciparum from Sri Lanka. All patients treated with SP had an adequate clinical response. Eighty-five percent (23 of 27) of pure field isolates carried parasites with double mutant alleles of Pf-dhfr (C59R + S108N) and showed about 200-fold higher levels of resistance to pyrimethamine than the wild type in a yeast system. None of the isolates had either known or novel mutations at other positions in the dhfr domain. In contrast, 67% (20 of 30) of the isolates carried parasites that were wild type for Pf-dhps. In Sri Lanka, detection of the triple mutant allele of Pf-dhfr will require tracking mutations at codon 51
Potential use of allele distribution at codon 51 of Plasmodium falciparum dihydrofolate reductase (pfDhfr) gene as evidence for early clinical failures to sulfadoxine-pyrimethaniine in an operational area in the Northern Province of Sri Lanka
(University of Kelaniya, Sri Lanka, 2004) Hapuarachchi, H.A.C.; Dayanath, M.Y.D.; Abeysundara, S.; Bandara, K.B.A.T.; Abeyewickreme, W.; de Silva, N.R.
Abstract available
Role of Aedes albopictus in transmitting dengue virus in some endemic areas in Kurunegala District.
(University of Kelaniya, 2003) Hapugoda, M.D.; de Silva, N.R.; Abeysundara, S.; Bandara, K.B.A.T.; Dayanath, M.Y.D.; Abeyewickreme, W.
Abstract Available