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    Dr. Mahendra Maharjan

    Gastrointestinal (GI) infection is predominant globally, especially in people with low socio-economic status with existing illiteracy, ignorance, poor housing and lifestyle, and the surrounding environment. It has been implicated as a... more
    Gastrointestinal (GI) infection is predominant globally, especially in people with low socio-economic status with existing illiteracy, ignorance, poor housing and lifestyle, and the surrounding environment. It has been implicated as a significant public health concern in the rural parts of many developing countries like Nepal. This study aimed to determine the diversity and prevalence of GI parasites in the highly marginalized indigenous Chepang communities in central Nepal. One hundred fresh stool samples of Chepangs were collected and preserved in 2.5% potassium dichromate solution. The samples were analyzed by direct wet mount, sedimentation, flotation, and acid-fast techniques and examined under the microscope at the total magnifications of 100Å~, 400Å~, and 1000Å~. We detected 97% prevalence rates with eight protozoan and six helminth parasites. Considering the infection’s concurrency, mixed pattern of infection was found to be higher than single pattern. Mixed infections from two to seven parasitic species were differently recorded in different samples. We also found that people’s eating habits were associated with GI parasitism (p=0.0034). “One Health” Approach/Principle accompanied by the detailed molecular and epidemiologic studies of parasitic transmission is required to identify the causal evidence critical in controlling and preventing parasitic infections.
    Background Sixty-three out of 77 districts reported lymphatic filariasis (LF) endemic in Nepal. Mass drug administration (MDA) with diethylcarbamazine (DEC) and albendazole (ALB) treatment program was continued for 6 to 11 rounds in these... more
    Background Sixty-three out of 77 districts reported lymphatic filariasis (LF) endemic in Nepal. Mass drug administration (MDA) with diethylcarbamazine (DEC) and albendazole (ALB) treatment program was continued for 6 to 11 rounds in these districts. Nepal government has stopped the MDA program based on the transmission assessment survey (TAS) report of 2014 and 2018 indicating Wuchereria bancrofti antigenemia prevalence < 2%. But the persistence of low levels of the circulating filarial antigen (CFA) in some foci of four endemic districts of Central Nepal, i.e., 0.4% in Dhading, 0.7% in Mahottari, 0.21% in Lalitpur and 1.2% in Bara district could responsible for enhancing the risk of infection resurgence. Hence the present study was designed to assess antigenic prevalence using Filariasis Test Strip (Alere, Scarborough ME) in children born after MDA in hotspot areas of four endemic districts of Central Nepal. Results The present study covers 70% children of the eligible populatio...
    Taenia solium is a predominant food-borne parasitic zoonosis (FBPZ) in Nepal. Using the PRECEDE framework, as defined by Green and Kreuter, we can identify the factors behind the high incidence of this disease. Armed with this... more
    Taenia solium is a predominant food-borne parasitic zoonosis (FBPZ) in Nepal. Using the PRECEDE framework, as defined by Green and Kreuter, we can identify the factors behind the high incidence of this disease. Armed with this information, we can define the actions necessary to control T. solium. In accordance with the first step of PRECEDE, social assessment, we set the goal of decreasing the potential for T. solium transmission in Nepal by the year 2003. This goal has yet to be endorsed by policy makers. However, an epidemiological assessment based on hospital data alone showed that T. solium is an endemic problem in urban Nepal that must be addressed. Based on behavioral and environmental assessments (Steps 1 and 2 of PRECEDE-PROCEED), we defined the following action objectives to be achieved by 2003: 1) Train meat producers and sellers to detect contaminated pork and avoid selling it, 2) Improve pig husbandry to limit the animals' access to human feces, 3) Construct hygienic model slaughterhouses. These improvements could control the meat-producing environment, thus limiting the potential for cross-carcass contamination and other hygiene deficiencies associated with the spread of T. solium. An educational and ecological assessment shows all predisposing, reinforcing and enabling factors are present in Nepal, consistent with PRECEDE requirements. While T. solium is clearly defined as a health problem according to PRECEDE, there remain significant hurdles to controlling it. These hurdles lie in administration and policy, where standardized law-enforcement and meat inspection practices are needed. Finally, the government of Nepal must assign high priority to T. solium control, as it is a preventable, yet prevalent disease.
    Antimonial-containing drugs are the first line of treatment against Leishmaniasis. Resistance to antimonials in Leishmania is proposed to be due to reduced uptake of trivalent antimony (SbIII) through the aquaglyceroporin (AQP1). We... more
    Antimonial-containing drugs are the first line of treatment against Leishmaniasis. Resistance to antimonials in Leishmania is proposed to be due to reduced uptake of trivalent antimony (SbIII) through the aquaglyceroporin (AQP1). We investigated the uptake of SbIII and involvement of aquaglyceroporin in developing antimony resistance phenotype in Leishmania donovani clinical isolates. SbIII accumulation, copy number of AQP1 gene, and transcript levels were compared in antimony-sensitive versus -resistant isolates. Antimony-resistant field isolates showed reduced uptake of SbIII. The copy number of AQP1 gene showed higher copy number in the antimony-resistant isolates when compared with the sensitive isolates and did not correlate to the reduced uptake of SbIII. Downregulation of AQP1 RNA levels was not consistently found in the antimony-resistant isolates. Our studies indicate that while downregulation of AQP1 may be one of the mechanisms of antimony resistance, it is however not an...
    Soil transmitted helminthiasis (STHs) are endemic in Nepal but since the country territory is extremely heterogeneous, a multidisciplinary assessment is required to evaluate the risk of infection in different areas. Prevalence data were... more
    Soil transmitted helminthiasis (STHs) are endemic in Nepal but since the country territory is extremely heterogeneous, a multidisciplinary assessment is required to evaluate the risk of infection in different areas. Prevalence data were retrieved with systematic literature search and geographical coordinates were assigned to each survey site. Spatial stratification was then implemented considering land use and ecological parameters. STH transmission boundaries were tested after reference criteria and elevation was evaluated as additional predictor: the elevation threshold of 3057 m above sea level is demarking the STH transmission limit. Areas above this threshold are safe, but since lodging in at-risk sites is a compulsory stopover for international travelers, STH risk exposure should be considered for every travel to the country.
    NZFHRC is primarily a research organization and its main interest in resource expansion is in securing funding for research on zoonotic diseases, animal and human health of relevance in Nepal. Its interest in a healthier urban development... more
    NZFHRC is primarily a research organization and its main interest in resource expansion is in securing funding for research on zoonotic diseases, animal and human health of relevance in Nepal. Its interest in a healthier urban development of wards 19 and 20, and potential to scale up to other wards in Kathmandu city will be pursued in a role of facilitation and accompaniment with local stakeholder groups for local development. It will act as broker between local groups, government programs and national and international donors supporting development work in the city, also providing capacity building and technical feedback to the different actors.
    A simple colorimetric β-lactamase assay for quantifying Leishmania amastigotes in macrophages grown in microtiter plates has been reported. The β-lactamase gene was integrated into the rRNA region of the genome, thereby allowing for... more
    A simple colorimetric β-lactamase assay for quantifying Leishmania amastigotes in macrophages grown in microtiter plates has been reported. The β-lactamase gene was integrated into the rRNA region of the genome, thereby allowing for high-level stable expression of the enzyme. Both visceral leishmaniasis (VL) and post-kala azar dermal leishmaniasis (PKDL) isolates were transfected with β-Lactamase gene. These β-lactamase-expressing promastigotes were used for infecting intracellular J774A.1 macrophages in vitro. Quantification was done by a colorimetric readout with CENTA™ β-lactamase as substrate and with an optical density plate reader. The assay was carried out in 96-well plates. Results obtained demonstrate that this methodology could be a valuable high-throughput screening assay for checking efficacy of anti-leishmanial drugs in the clinical isolates.
    A genus of Hysterothylacium sp. has been reported from digestive tract of fishes, birds and piscivorous mammals. The present paper described the first record of genus and new species of Hysterothylacium punensis (sp.n.) from the reptiles,... more
    A genus of Hysterothylacium sp. has been reported from digestive tract of fishes, birds and piscivorous mammals. The present paper described the first record of genus and new species of Hysterothylacium punensis (sp.n.) from the reptiles, Amphiesma stolatum. The nematode parasite was taxonomically similar to genus Hysterothylacium reported earlier form different hosts on the basis of characteristic oesophagus. Larger size and pointed tail differs from other species reported earlier indicating the new species.
    Intestinal parasitic infections associated with anaemia during pregnancy have direct negative impact on the health of expected mother and developing baby. In order to assess the association between anaemia and parasitic infection during... more
    Intestinal parasitic infections associated with anaemia during pregnancy have direct negative impact on the health of expected mother and developing baby. In order to assess the association between anaemia and parasitic infection during pregnancy, a total of 200 stool samples from pregnant women on their first consultation to antenatal service in Koshi Zonal Hospital were collected from April to August 2012. The stool samples were examined for intestinal parasites by direct smear technique, while haemoglobin level of pregnant women were collected from laboratory record of the hospital. Out of 110 anaemic pregnant women 40(36.3%) had parasitic infection, while from 90 non-anaemic pregnant women; only 18(20%) of them were infected with intestinal parasites. The association of anaemia with intestinal parasite was statistically significant (p<0.008). The prevalence of Hookworm (76.9%) was most prevalent infection followed by Ascaris lumbricoides (73.3%) in anaemic pregnant women. The...
    A simple colorimetric beta-lactamase assay for quantifying Leishmania amastigotes in macrophages grown in microtiter plates has been reported. The beta-lactamase gene was integrated into the rRNA region of the genome, thereby allowing for... more
    A simple colorimetric beta-lactamase assay for quantifying Leishmania amastigotes in macrophages grown in microtiter plates has been reported. The beta-lactamase gene was integrated into the rRNA region of the genome, thereby allowing for high-level stable expression of the enzyme. Both visceral leishmaniasis (VL) and post-kala azar dermal leishmaniasis (PKDL) isolates were transfected with beta-Lactamase gene. These beta-lactamase-expressing promastigotes were used for infecting intracellular J774A.1 macrophages in vitro. Quantification was done by a colorimetric readout with CENTA beta-lactamase as substrate and with an optical density plate reader. The assay was carried out in 96-well plates. Results obtained demonstrate that this methodology could be a valuable high-throughput screening assay for checking efficacy of anti-leishmanial drugs in the clinical isolates.
    Parasitic diseases pose significant conservation threat in conservation of Red panda. In order to assess the parasitic burden in Red panda of Illam district, Nepal, 14 faecal samples were aseptically collected from community forest of... more
    Parasitic diseases pose significant conservation threat in conservation of Red panda. In order to assess the parasitic burden in Red panda of Illam district, Nepal, 14 faecal samples were aseptically collected from community forest of Illam using line transect method following the GPS location. The samples were examined using standard concentration techniques. All the collected samples were found to be positive for both protozoan and helminth parasites. The recorded protozoan parasites includes Eimeria sp., Entamoeba sp., and Balantidium sp. with 64.28%, 57.14% and 14.28% proportion respectively. Similarly the proportion of seven helmithes parasites revealed Oxyuris (100%), Baylisascaris (57.14%), Trichostrongylus (50%), Strongyloides (50%), Trichuris (42.8%), Crenosoma (42.85%) and Hookworm (35.7%). The most of the samples (78.52%) revealed either multiple parasitic infection or triple infection (21.42%) with low to moderate intensity of infection. In conclusion, The parasitic burd...
    Bats are the only active flying placental mammals and are traditionally classified into mega- and microbats, which are, respectively, herbivorous and insectivorous in feeding habit. Though deforestation, habitat destruction, natural... more
    Bats are the only active flying placental mammals and are traditionally classified into mega- and microbats, which are, respectively, herbivorous and insectivorous in feeding habit. Though deforestation, habitat destruction, natural calamities, illegal hunting, and climate changes are the challenging threats for bats, the role of existing gastrointestinal (GI) parasites have not been evaluated yet in Nepal. Thus, the current study aims to determine the prevalence of GI parasites in bats from the Shaktikhor area at the Chitwan district of Southcentral Nepal. From July 2018 to February 2019, a total of 60 fecal samples of bats (30 from frugivorous bats and 30 from the insectivorous bats) were collected. These samples were preserved at 2.5% potassium dichromate solution. The fecal examination was carried out by the direct wet mount, concentrations, acid-fast staining, and sporulation techniques. Overall results showed the prevalence rate of 80% GI parasites. The parasites detected in t...
    Tuberculosis (TB) is one of the major public health problems in the developing countries like Nepal. The present study was carried out in Jutpani VDC of Chitwan Nepal from July to December 2012 with the objective to determine the... more
    Tuberculosis (TB) is one of the major public health problems in the developing countries like Nepal. The present study was carried out in Jutpani VDC of Chitwan Nepal from July to December 2012 with the objective to determine the situation of Tuberculosis in Jutpani VDC, Chitwan. During the study period, a total of 600 sputum samples from 200 TB suspected patients were collected and examined in the Laboratory of Jutpani Primary Health Center (PHC). Diagnosis was made after staining the sputum smear by Z-N staining method and examined under light microscope. Out of 200 TB suspected patients, 18(9%) were found to be AFB positive. Among patients diagnosed as having pulmonary Tuberculosis (PTB), males (55.56%) were found to be infected more than females (44.44%) which was found to be statistically insignificant (Χ2cal. = 0.4524, P<0.01). Highest prevalence of TB infection (36.89%) was found to be in the age group of 30-40 years. A questionnaire survey of 57 Pulmonary Tuberculosis (PT...
    Ostrich and Emu farming have been lunched with a very new concept to Nepalese market for their product in which parasitic diseases may cause significant effect to their production. In order to determine prevalence of gastrointestinal... more
    Ostrich and Emu farming have been lunched with a very new concept to Nepalese market for their product in which parasitic diseases may cause significant effect to their production. In order to determine prevalence of gastrointestinal parasites of Emu, a total of 100faecalsamples were collected during the month of May/July 2015. All samples were microscopically examined by using direct smear and concentration techniques (floatation and sedimentation).Out of 100 faecal samples, 65% were found positive for gastrointestinal parasites. Overall, seven different species of gastrointestinal parasites including two protozoan, three nematodes and two cestodes were recorded. Amongprotozoan parasites, Eimeria sp. (30%) was more prevalent compared to Entamoeba sp.(10%). Among helminthes parasites, Ascaris sp. (15%)showed the higher prevalence rate followed by Dromaestrogylus sp. (10%), Davainea sp.(9%), Raillietina sp. (5%) and Heterakis sp. (5%). This study suggested that parasitic infection co...
    Anaemia is the common problem during pregnancy in developing countries like Nepal.  A total of 200 stool samples for parasitic infection and their haemoglobin level data were collected from the pregnant women visiting TUTH. The overall... more
    Anaemia is the common problem during pregnancy in developing countries like Nepal.  A total of 200 stool samples for parasitic infection and their haemoglobin level data were collected from the pregnant women visiting TUTH. The overall prevalence of intestinal parasitic infection and anaemic rate among pregnant women was found to be 35% and 50%. Among 100 anaemic pregnant women 58 women were infected with intestinal parasites. The association of anaemia with intestinal parasitic infection was statistically significant (P > 0.05). The most dominant parasite among anaemic pregnant women was A. lumbricoides followed by H. nana. Total five different types of intestinal parasites were identified in this study. Among them A. lumbricoides (30.5%), H. nana 6(3%), E. histolytica 5(2.5%), T. trichiura 2(%) and S. stercoralis 2(1%) respectively. Pregnant women with single parasitic infection were found to be 64(32%) and multiple infection were 6(3%). Intensity of parasitic infection found t...
    The purpose of this study was to record the species of chewing lice parasitising Gyps bengalensis (Gmelin, 1788), the white-rumped vulture, in Pithauli, Nawalparasi District, Nepal, from February to June 2017. Three louse species were... more
    The purpose of this study was to record the species of chewing lice parasitising Gyps bengalensis (Gmelin, 1788), the white-rumped vulture, in Pithauli, Nawalparasi District, Nepal, from February to June 2017. Three louse species were identified: Cuculiphilus (Aegypiphilus) gypsis (Eichler, 1944), Colpocephalum sp., and the new species Aegypoecus bengalensis, described herein. 
    Parasites of two high altitude ruminants Himalayan Tahr (Near Threatened) and Barking Deer (Vulnerable) were examined from the Rara National Park, located at 3000 – 4000 m altitude of Nepal, for the first time. A total of 51 faecal... more
    Parasites of two high altitude ruminants Himalayan Tahr (Near Threatened) and Barking Deer (Vulnerable) were examined from the Rara National Park, located at 3000 – 4000 m altitude of Nepal, for the first time. A total of 51 faecal samples, 17 from Himalayan Tahr and 34 from Barking Deer were collected in the month of May/June 2012 and 2013. Parasites were found in all the samples of Himalayan Tahr and 33 samples (97.06%) of Barking Deer. Coccidian oocysts (Eimeria sp.), eggs of cestodes (Moniezia sp.) and gastrointestinal nematodes (Strongyloides sp., Trichuris sp., Oxyuris sp., Ascaris sp., Trichostrongylus sp. and Haemonchus sp.) and bronchopulmonary nematode larvae (Dictyocaulus sp. and Muellerius sp.) were identified by means of coprological techniques. Himalayan Tahrs were found to be highly infected with Eimeria sp. (88.24%) and Moniezia sp. (70.59%) compared to Barking Deers, Eimeria sp. (73.53%) and Moniezia sp. (47.06%). In Himalayan Tahr, prevalence of Oxyuris was found t...
    Blackbuck (Antilope cervicapra) is Near Threatened species which are conserved in blackbuck Conservation Area (BCA), Khairapur, Bardiya and Shuklaphanta Wildlife Reserve (SWR), Kanchanpur district. The present study was conducted to... more
    Blackbuck (Antilope cervicapra) is Near Threatened species which are conserved in blackbuck Conservation Area (BCA), Khairapur, Bardiya and Shuklaphanta Wildlife Reserve (SWR), Kanchanpur district. The present study was conducted to determine the parasitic infection in blackbuck of BCA and SWR. A total of 150 and 70 fresh faecal samples of blackbuck were collected from BCA and SWR respectively and examined by floatation, sedimentation and Stoll's counting technique. The overall prevalence of GI parasites was found to be 90.00%. The protozoan and helminthic parasitic prevalence revealed 55% and 89% respectively in both the study area. Blackbuck of BCA were found to be infected with 12 different species of parasites which includes Entamoeba sp. (20%) and Eimeria sp. (45.33%) among protozoa; Paramphistomum sp. (25.33%) and Fasciola sp. (17.33%) among trematodes; Moniezia sp. (14%) among cestode; Trichostrongylus sp. (75.33%), Ascaris sp. (57.33%), Haemonchus sp. (18%), Strongyloide...
    A total of 22 faecal samples of Red panda were collected in the month of May/June 2011 and 21 faecal samples from the same site during the month of May/June 2012. All the samples were microscopically examined by faecal floatation and... more
    A total of 22 faecal samples of Red panda were collected in the month of May/June 2011 and 21 faecal samples from the same site during the month of May/June 2012. All the samples were microscopically examined by faecal floatation and sedimentation techniques. Out of 43 faecal samples, 40 samples (93.02%) were found positive for gastro-intestinal parasites. Altogether, 12 different species of gastro-intestinal parasites were recovered from Red panda. Among them, two species of protozoan parasites and 10 species of helminthes were observed. In protozoan parasites, Eimeria (67.44%) was more prevalent as compared to Entamoeba (62.79%). Among helminthes, Oxyuris sp. showed the highest prevalence rate followed by Toxoascaris sp. (48.84%), Hookworm (44.19%), Baylisascaris sp., Crenosoma sp. (34.88%), Strongyloides sp., Moniezia sp. (18.60%), Trichuris sp., etastrongylus sp. (4.65%) and Angiostrongylus sp. (2.33%). Only one species of cestoda i.e. Moniezia sp. was found but trematodes and a...
    A total of 495 stool samples from the school children aged 9-12 years from Bhaktapur were examined for helminth parasites by direct smear method. Out of 495 children, 137 (27.68%) were found positive for one or more intestinal helminthic... more
    A total of 495 stool samples from the school children aged 9-12 years from Bhaktapur were examined for helminth parasites by direct smear method. Out of 495 children, 137 (27.68%) were found positive for one or more intestinal helminthic parasites. Ascaris lumbricoides (22.63%) showed highest prevalence rate followed by Trichuris trichiura (6.06%), Strongyloides stercoralis (1.82%), Hookworm (1.62%), Taenia sp. (1.01%), Hymenolepis nana (0.81%) and Enterobius vermicularis (0.40%). The helminthic infection was found to be almost equal in male and female children and statistically no signifi cant difference was found (χ2 = 8.31×10-6, p>0.05). Higher percentages of students were infected with single parasites than double and multiple infections. All 137 positive cases were treated with single oral dose of 400 mg albendazole. Post-treatment stool samples were collected four weeks after treatment to determine the cure rate. Stool samples were again collected 24 weeks post-treatment to...
    Males and females specimens of Amblyomma were collected from Orthriophis hodgsoni (Squamata: Colubridae) caught during routine herpetological work in Kathmandu. Morphological characteristics led to the diagnosis of A. varanense,... more
    Males and females specimens of Amblyomma were collected from Orthriophis hodgsoni (Squamata: Colubridae) caught during routine herpetological work in Kathmandu. Morphological characteristics led to the diagnosis of A. varanense, constituting the second Nepalese species for the genus after the collection of Amblyomma gervaisi, also from a colubrid snake, almost 100 years ago. Amblyomma varanense is the 55th species found in the country, and preceded for the collection of 21 species of Haemaphysalis, 14 Ixodes, 6 Rhipicephalus, 6 Hyalomma, 4 Dermacentor, 1 Amblyomma, 1 Anomalohimalaya and 1 species of Nosomma. Eleven and 19 species have been found on humans and domestic mammals, respectively, evidencing the medical and economic importance of Nepalese Ixodidae.
    Meat is an important source of protein and a valuable commodity in resource-poor communities. In many developing countries, lack of appropriate slaughtering facilities and unsatisfactory slaughtering techniques are causing unnecessary... more
    Meat is an important source of protein and a valuable commodity in resource-poor communities. In many developing countries, lack of appropriate slaughtering facilities and unsatisfactory slaughtering techniques are causing unnecessary losses of meat as well as invaluable by-products from animal carcasses. Slaughtering places are frequently contaminated and may not be protected against dogs, rodents and insects. Meat products coming from such conditions are often deteriorated due to bacterial infection or contaminated, which may cause food poisoning or diseases in consumers. In many developing countries, regulations concerning meat inspection and/or control are inadequate or non-existent allowing consumers to be exposed to pathogens including zoonotic parasites. In Nepal, buffaloes contribute about 64% of the meat consumed, followed by goat meat (20%), pork (7%), poultry (6%) and mutton (2%). Goat and poultry meat is acceptable to all castes of people while buffalo meat is consumed mainly by the Newar ethnic group. Previously, pork was consumed only by people belonging to low castes, however, in recent years, the consumption of pork has increased in higher castes as the caste system has become more relaxed. Until recently, there were no official meat inspection regulations in the country, however, in 1999, the national government legislated an as-yet-to-be implemented Animal Slaughtering and Meat Inspection Act which mandates slaughterhouse construction and meat inspection and control. Due to the lack of implementation of the Meat Inspection Act and resultant absence of meat inspection, meat from sick or parasite-infected animals is serving as a source of infection to humans as well as other animals. In addition, meat quality is adversely affected by careless handling conditions in the slaughtering places as well as in the meat markets or shops. For improvement in animal slaughtering and meat inspection in both rural and urban areas of Nepal, several strategies are to be recommended. Sustainable capacity building should be introduced including training of veterinarians, meat inspectors and butchers as well as building of slaughter facilities. Government policies on slaughter procedures including ante-mortem examination, meat inspection and stamping of meat should be implemented. Programmes should be instituted with strong focus on prevention and control of meat-borne diseases to reduce infection risk of consumers and meat handlers and to avoid contamination of the environment. Lastly, emphasis should be put on improving the animal husbandry system in Nepal. These same actions can be undertaken in other developing countries to assist with improving meat inspection and control, thus helping with prevention and control of cysticercosis as well as other important meat-borne diseases.

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