Circulating filarial antigen detection in brugian filariasis.

Human lymphatic filariasis (LF) is a major cause of disability globally. The success of global elimination programmes for LF depends upon effectiveness of tools for diagnosis and treatment. In this study on stage-specific antigen detection in brugian filariasis, L3, adult worm (AW) and microfilarial antigenaemia were detected in around 90-95% of microfilariae carriers (MF group), 50-70% of adenolymphangitis (ADL) patients, 10-25% of chronic pathology (CP) patients and 10-15% of endemic normal (EN) controls. The sensitivity of the circulating filarial antigen (CFA) detection in serum samples from MF group was up to 95%. In sera from ADL patients, unexpectedly, less antigen reactivity was observed. In CP group all the CFA positive individuals were from CP grade I and II only and none from grade III or IV, suggesting that with chronicity the AWs lose fecundity and start to disintegrate and die. Amongst EN subject, 10-15% had CFA indicating that few of them harbour filarial AWs, thus they might not be truly immune as has been conventionally believed. The specificity for antigen detection was 100% when tested with sera from various other protozoan and non-filarial helminthic infections.

Extra-intestinal complications of Ascaris lumbricoides infections in India: A systematic review and meta-analysis.

The aberrant migration of Ascaris lumbricoides may cause extra-intestinal ascariasis (EIA) involving hepato-biliary-pancreatic (HBP) or other extra-gastro-intestinal (EGI) organs. We performed a systematic review and meta-analysis to study the risk factors and clinical presentations of EIA, and differences in HBP and EGI ascariasis. Medline, Web of Science and Embase were searched for cases of EIA in the English language from India. From 1204 articles, 86 studies (105 cases) were included. The majority of the cases involved the HBP system (78%). Among HBP ascariasis, the most commonly involved site was the bile duct (53.6%). Females had 11.3 times higher odds (95% CI 2.852 to 44.856; p=0.001) of HBP ascariasis, while the pediatric population had lower odds (OR=0.323). Previous gallbladder disease was significantly associated with HBP ascariasis in adults (p=0.046), while a significantly higher number of cases of EGI ascariasis were observed among pediatric patients (p=0.003). Ocular symptoms occurred exclusively in the pediatric population (p=0.017). Overall, death was reported in 3.8% of patients (n=4). This review emphasizes the importance of the complications of EIA. It encourages future research into issues such as the reasons of higher gall bladder ascariasis in females and the implications of Ascaris-related complications following biliary tract interventions. It also suggests considering Ascaris as a differential diagnosis for airway obstuction in intubated critically ill patients.

Is routine medical examination of food handlers enough to ensure food safety in hospitals?

Nosocomial food outbreaks due to infected food handlers is primarily due to inadequate knowledge and faulty practices of food handlers during diarrhoeal episodes. The aim of this study was to assess: 1) prevalence of enteropathogen infection among food handlers working in our hospital during 2007 to 2011 and 2) adequacy of precautions taken by them during gastroenteritis episodes. Stool samples submitted by food handlers during 2007 to 2011 were examined for the presence of enteropathogens by standard methodology. For the second part of the study, a questionnaire regarding practices during episodes of diarrhoea in food handlers or their family members was handed out to willing participants. During the years 2007, 2008, 2010 and 2011 respectively, 3.9%, 9.8%, 5.1% and 9.4% food handlers were found infected with enteropathogens. The most common parasite detected was Entamoeba histolytica. Bacterial enteropathogens prevalence was very low during these years. There was high awareness (78.8%) among the food handlers regarding routine testing of faeces. Only 64.7% knew that it was important to report for purpose of treatment and leave. While 9.4% had suffered from diarrhoeal episodes in between intervals of annual microbiological testing, only 4.7% took appropriate treatment and availed medical leave. A regular training programme on food safety should be established and emphasis should be laid on mandatory reporting and stool testing of kitchen personnel as well as abstaining from work till they are medically fit.

Serum immunoglobulin G, M and A response to Cryptosporidium parvum in Cryptosporidium-HIV co-infected patients.

BACKGROUND: Cryptosporidium parvum, the protozoan parasite, causes a significant enteric disease in immunocompromised hosts such as HIV patients. The present study was aimed to compare serum IgG, IgM and IgA responses to crude soluble antigen of C. parvum in HIV seropositive and seronegative patients co-infected with Cryptosporidium and to correlate the responses with symptomatology. METHODS: Cryptosporidium parvum specific serum antibody (IgG, IgM and IgA) responses were assessed by ELISA in 11 HIV seropositive Cryptosporidium positive (Group I), 20 HIV seropositive Cryptosporidium negative (Group II), 10 HIV seronegative Cryptosporidium positive (Group III), 20 HIV seronegative Cryptosporidium negative healthy individuals (Group IV) and 25 patients with other parasitic diseases (Group V). RESULTS: A positive IgG and IgA antibody response was observed in significantly higher number of Cryptosporidium infected individuals (Gp I and III) compared to Cryptosporidium un-infected individuals (Gp II, IV and V) irrespective of HIV/immune status. Sensitivity of IgG ELISA in our study was found to be higher as compared to IgM and IgA ELISA. The number of patients with positive IgG, IgM and IgA response was not significantly different in HIV seropositive Cryptosporidium positive patients with diarrhoea when compared to patients without diarrhoea and in patients with CD4 counts <200 when compared to patients with CD4 counts >200 cells/microl. CONCLUSION: The study showed specific serum IgG and IgA production in patients infected with Cryptosporidium, both HIV seropositive and seronegative as compared to uninfected subjects suggesting induction of Cryptosporidium specific humoral immune response in infected subjects. However, there was no difference in number of patients with positive response in HIV seropositive or seronegative groups indicating that HIV status may not be playing significant role in modulation of Cryptosporidium specific antibody responses. The number of patients with positive IgG, IgM and IgA response was not significantly different in patients with or without history of diarrhoea thereby indicating that Cryptosporidium specific antibody responses may not be necessarily associated with protection from symptomatology.

Evaluation of staining techniques, antigen detection and nested PCR for the diagnosis of cryptosporidiosis in HIV seropositive and seronegative patients.

The study was designed to determine the efficacy of modified Ziehl-Neelsen (ZN), safranine methylene blue (SM) staining, antigen detection ELISA and a nested PCR assay (specific for Cryptosporidium parvum) for detection of Cryptosporidium in HIV seropositive and seronegative patients with diarrhoea. Cryptosporidium was detected in 10 (4.9%), 9 (4.4%), 39 (18.9%) and 27 (13.1%) of 206 HIV seropositive and 7 (4.6%), 6 (3.9%), 21 (13.7%) and 17 (11.1%) of 153 HIV seronegative patients by ZN staining, SM staining, antigen detection ELISA and PCR, respectively. None of the 50 apparently healthy control subjects was found to be infected with Cryptosporidium by any of the techniques. Based on the criteria of 'true positive' samples positive by at least any two techniques out of ZN staining, antigen detection and PCR, sensitivity of ZN and SM staining techniques was 37% and 33.3% in HIV seropositive and 41.2% and 35.3% in seronegative patients, respectively. Sensitivity of antigen detection ELISA was 92.6% and 94.1% in HIV seropositive and seronegative patients, respectively, while sensitivity of PCR was 100% each in HIV seropositive and seronegative patients. Specificity of all three techniques, i.e. ZN, SM staining and PCR was 100% in both HIV seropositive and seronegative patients while specificity of antigen detection was 92.2% and 96.3% in HIV seropositive and seronegative patients, respectively. The staining techniques were found less sensitive as compared to antigen detection and PCR for detection of Cryptosporidium in HIV seropositive patients with CD4 count >200cells/microl.

Intestinal bacterial and parasitic infections among food handlers in a tertiary care hospital of North India.

BACKGROUND: Intestinal infection is still an important public health problem in developing countries like India. Food handlers may be infected by a wide range of enteropathogens and have been implicated in the transmission of many infections to the public in the community and to patients in hospitals. AIM: To study the presence of enteropathogenic bacteria and parasites in food handlers working in the food service establishments of a tertiary care centre in North India. METHOD: The stool samples received from food handlers during January 2001 to December 2006 were examined by wet mount, iodine mount and modified acid fast staining directly and after formol ether concentration technique for parasites. For enteropathogenic bacteria, samples were inoculated onto MacConkey's agar, Deoxycholate Citrate Agar, Xylose Lysine Deoxycholate agar (XLD) as per the WHO protocol. RESULTS: During the years 2001-2006 respectively, 8.75%, 16%, 1.4%, 6.75%, 2.56% and 6.75% food handlers were infected with enteropathogens. The parasitic infections in our study were 1.3 to 7% while the enteropathogenic bacteria were reported from 0% to 13.3% during the years 2001-6. Giardia was the most common parasite while Shigella was the most common bacteria isolated from food handlers. During the year 2001, there was an outbreak of ETEC in the neonatal ICU, Advanced Paediatric Centre, PGIMER, which was traced back to a food handler involved in the preparation of the milk feed. CONCLUSION: Routine screening of food handlers is a valuable tool for prevention of nosocomial food-borne infections.

Specific antibody detection in serum, urine and saliva samples for the diagnosis of cystic echinococcosis.

Serum, saliva and urine samples of 25 clinically and radiologically diagnosed cystic echinoccosis (CE) patients, 25 clinically suspected cases of CE, 15 other parasitic disease controls and 25 healthy controls were evaluated for anti-hydatid antibody response by ELISA. The sensitivity of serum, saliva and urine was found to be 72, 56 and 84%, respectively, while specificity was 76% in all the samples. Urine showed significantly higher (p<0.05) sensitivity than that of saliva samples but not significantly higher (p>0.05) than that of serum samples. There was no significant difference in the immune response of patients with hepatic versus extrahepatic cysts and single versus multiple cysts. Thus, biological fluid like urine may be used as an alternative or as an adjunct to serum samples by virtue of its non-invasive, easy collection and similar sensitivity and specificity.

Kinetics of microfilaraemia & antigenaemia status by Og(4)C(3) ELISA in bancroftian filariasis.

BACKGROUND & OBJECTIVE: Bancroftian filariasis caused by Wuchereria bancrofti is endemic in many parts of India. In recent years diagnosis of W. bancrofti infection has been revolutionized with the availability of filarial antigen tests, which is important in monitoring success of chemotherapy. We carried out this study to measure microfilariaemia and antigenemia levels in bancroftian microfilariae (mf) carriers at 1 yr follow up after chemotherapy, in lymphoedema patients and in endemic controls from a filariasis endemic area in Tamil Nadu State using Og(4)C(3) ELISA to identify the best marker to assess success of chemotherapy. METHODS: Serum samples were collected from 30 bancroftian microfilaremic (Mf) carriers pre-treatment and at sequential intervals (7,30,60,90,180 and 365 days) following treatment with diethylcarbamazine (DEC:6mg/kg body weight, single dose), 30 lymphoedema patients (without treatment) at periodic intervals, and 68 control subjects (24 endemic normal subjects in filariasis endemic area in Tamil Nadu State, 24 non-endemic normal subjects residing in Chandigarh, India; 5 brugian filariasis, 5 endemic control subject in brugian filariasis endemic area and 10 other disease controls). The circulating antigen of W. bancrofti was measured quantitatively using Og(4)C(3) ELISA kit. RESULTS: In Mf carriers, there was no significant difference in microfilariae count in pre- and post-treatment (PT) samples till day 30 while significant differences were observed in pre- and sequentially collected post-treatment (PT) samples day 60 to 180 (P<0.001), day 365 (P<0.005). However, there was no significant difference in antigenaemia levels between pre-treatment (day 0) and PT samples collected on day 7 onwards till day 365. Though of the 19 patients who could be followed up till 365 days PT, 4 (21%) were amicrofilaraemic, none became antigen negative. No significant difference was found in antigenaemia levels in sequentially collected samples from lymphoedema patients. Significant differences were observed in antigenaemia levels in samples collected at the start of study in mf carriers as compared to lymphoedema patients and endemic normal subjects (P<0.001). Subjects (non-endemic control) residing in filariasis free area (24), brugian endemic area (5), B.malayi infected patients (5) and patients with other parasitic diseases (10) were found antigen negative. INTERPRETATION & CONCLUSION: Annual single dose of DEC therapy alone may not result in complete clearance of infection and detection of antigenaemia rather than microfilaraemia may be taken into consideration as an indicator of successful chemotherapy. The study supports the earlier view that filarial antigenaemia is relatively common in amicrofilaraemic and asymptomatic subjects in endemic areas and further studies are needed to determine the clinical significance, prognosis and effective management of such infections in endemic areas.

Increasing trends in seroprevalence of human hydatidosis in North India: a hospital-based study.

A retrospective analysis of laboratory data of 3290 clinically suspected and/or radiologically confirmed cases of hydatidosis revealed that 495 (15%) were positive for specific antibody response. Casoni's test was positive in 481/1938 (24.82%) patients. A significant increase (P<0.001) in seropositivity was observed during the last 5 years (23.12%, 1999-2003) as compared with previous years (10.97%, 1984-1998), and a similar increase (P<0.001) in positive Casoni's test was also observed (33.83%, 1999-2003 versus 21.38%, 1984-1998) during the same time period.

Stage-specific antibody response against two larval stages of Brugia malayi in different clinical spectra of brugian filariasis.

CONTEXT: T-cell hypo-responsiveness in microfilaria (Mf) carriers against the microfilarial stage antigen of Brugia malayi has been described, but no study has been carried out to assess antibody dynamics against stage-specific antigens. AIM: The work was carried out with the aim to assess stage-specific antibody responses against L3 and microfilarial stage antigens in brugian filariasis in an endemic area. SETTING AND DESIGN: Patients with different clinical spectra of brugian filariasis were recruited to evaluate antibody responses to brugian antigens. SUBJECTS AND METHODS: Serum samples were collected from patients with different clinical spectra and antibody response was evaluated for total immunoglobulin G (IgG), IgG isotypes (IgG1, IgG2, IgG3, IgG4) and immunoglobulin E (IgE) response to L3 and microfilarial stage by enzyme-linked immunosorbent assay. STATISTICAL ANALYSIS: Paired t-test and one-way analysis of variance were carried out to analyze the data. RESULTS: L3 and microfilarial stage antigens showed almost similar antibody responses in adenolymphangitis (ADL) and chronic pathology (CP) patients, however, diminished antibody response was observed with Mf stage antigen, especially with microfilaraemia. ADL patients had minimum antibody levels of all isotypes except IgG2 on day 0 which showed an increase subsequently, indicating suppression of antibody response during filarial fever. CP patients showed increase in IgE and decrease in IgG4 antibodies on day 365 indicating that these differences may be due to recent conversion into CP. CONCLUSION: A prominent hyporesponsiveness in microfilaraemic individuals against microfilarial stage, but not against the L3 stage of the same parasite was observed, concluding stage-specificity in humoral immune response in brugian filariasis.

Pathophysiology of visceral leishmaniasis - some recent concepts.

Visceral leishmaniasis is characterized by diversity and complexity of clinical manifestations ranging from asymptomatic infection to life threatening illness. Experimental evidence and clinical studies indicate multifaceted role of various factors leading to parasite survival and multiplication. In early stage of infection, generation of reactive oxygen and nitrogen intermediates play significant role in curtailing the parasite multiplication while in later phase on one hand, hepatic resistance is expressed by the dominant role played by nitric oxide synthase (NOS)-2 gene regulation and on the other hand, production of inhibitors of NOS-2 gene expression, interleukin 10 (IL-10) and transforming growth factor beta (TGFbeta) correlate well with reduced parasite killing. The hepatic infection is usually self-limiting due to production of multiple cytokine responses including moderate level of tumour necrosis factor (TNF) while in spleen excess TNF mediates destructive pathology. CD8+ T cells appear to play multiple roles comprising both cytotoxic activity and secretion of cytokines and chemokines. Capacity to produce ThI cytokines is associated with asymptomatic or subclinical self-healing infection. However, in symptomatic patients, Th I cytokine production is not depressed but there appears to be unresponsiveness to the stimuli of these cytokines. Experimental evidences indicate genetic basis for such a phenomenon.

Drug resistance in amoebiasis.

Amoebiasis caused by Entamoeba histolytica, is a major public health problem in developing countries. Morphologically similar E. dispar is non pathogenic. Because of the redefinition of E. histolytica and E. dispar, and the limited number of antiamoebic drugs available, a new approach to treat such individuals is necessary. The cost of treating asymptomatic individuals is highly exorbitant and not justifiable. The indiscriminate use of antiamoebic drugs can result in increased minimum inhibitory concentration (MIC) values against Entamoeba species, and treatment failure may emerge as an important public health problem. Development of new antiamoebic drugs is still in infancy and vaccine development appears to be distant dream. In future, the development of drug resistance may seriously affect the control of disease. This review discusses the factors involved in drug resistance mechanisms developed by the parasite.

Multidrug resistance in amoebiasis patients.

BACKGROUND & OBJECTIVES: Amoebiasis, caused by Entamoeba sp. a protozoan parasite, is a major public health problem in tropical and subtropical countries. The symptomatic patients are treated by specific chemotherapy. However, there are reports of treatment failure in some cases suggesting the possibility of drug resistance. The present study was therefore planned to assess the presence and expression of mRNA of multidrug resistance (MDR) gene in clinical isolates of Entamoeba histolytica and E. dispar. METHODS: Forty five clinical isolates of Entamoeba sp. [E. histolytica (15) and E. dispar (30)] were maintained in polyxenic followed by monoxenic medium. DNA and total RNA were extracted from clinical isolates of Entamoeba sp. and from sensitive strain of E. histolytica (HM1: IMSS) and subjected to polymerase chain reaction (PCR) and multiplex reverse transcription (RT)-PCR techniques. RESULTS: The 344 bp segment of E. histolytica DNA was seen by PCR using primers specific to EhPgp1 in all clinical isolates and sensitive strain of E. histolytica. Over expression of EhPgp1 was observed only in resistant mutant of E. histolytica; however, transcription of EhPgp1 was not seen in any clinical isolates and sensitive strain of E. histolytica. INTERPRETATION & CONCLUSION: The findings of the present study indicate that, so far, drug resistance in clinical isolates of E. histolytica does not seem to be a major problem in this country. However, susceptibility of clinical isolates of E. histolytica against various antiamoebic drugs needs to be investigated for better management.

Prevalence of anti-cysticercus antibodies in slum, rural and urban populations in and around Union territory, Chandigarh.

A comparative analysis for the prevalence of anti-cysticercus antibodies was carried out in urban, rural and slum population in & around Union territory of Chandigarh. Prevalence of anti-cysticercus antibodies in different population groups was found to be 17.3% with highest prevalence (24%) reported from slum areas followed by that of rural areas (20%) and least in the urban organized sectors (8%). Only 8% of the seropositive individuals had history suggestive of neurocysticercosis. Overall, females showed the highest anti-cysticercus response of 20.4%.

Presence of intracellular viruses in human Cryptosporidium isolates.

UNLABELLED: Cryptosporidium is a major cause of diarrheal illness mainly in children and immunocompromised adults. Disease severity ranges from asymptomatic or self-limited gastroenteritis to acute or chronic diarrhoea which may be associated with systemic features. Intracellular viruses that reside in many parasites have been incriminated in pathogenesis of diseases like trichomoniasis, leishmaniasis etc. Thus we attempted to detect and quantitate the intracellular viruses in Cryptosporidium isolates and sought to seek a relationship if any, with clinical features. Cryptosporidia in stool samples from immunocompromised patients and children were identified by microscopy and species differentiated by PCR-RFLP of 18s rRNA; further subgenotyped by sequencing of GP60 region. Copy number of dsRNA virus and 18srRNA was calculated in 56 Cryptosporidium isolates (39 C. hominis and 17 C. parvum). Viral copy number per oocyst was calculated as ratio of dsRNA virus copy number to 18s rRNA copy number. Viruses were detected in all the isolates. Mean CSpV/RNA ratio was 0.17±0.4 for C. hominis isolates compared with 0.12±0.11 for C. parvum isolates, however this difference was not statistically significant. Similarly no association of diarrhoea, vomiting, cough and fever was found with either CSpV copy number or with CSpV/rRNA ratio. KEY WORDS: Cryptosporidium, virus, immunocompromised, diarrhoea.

Comparative analysis of intestinal parasitic infections in slum, rural and urban populations in and around union Territory, Chandigarh.

A study was conducted in and around the union Territory, Chandigarh, India to estimate the prevalence of intestinal parasitic infections in different population groups. The stool samples from a total of 600 subjects selected by cluster sampling technique were examined by direct microscopy. The prevalence of intestinal parasitic infections was found to be 14.6% with highest prevalence of 19% from the slum area. Children were the most commonly affected group (18%) with those from slums showing the highest prevalence (24.6%). The most common parasite was Giardia (5.5%) followed by H. nana and Ascaris (2.8% and 2.7% respectively).

Sero-epidemiological survey of human cystic echinococcosis in Kashmir, North India.

BACKGROUND: Echinococcosis is a human and animal health problem in many endemic areas worldwide. There are numerous reports and hospital-based studies from Kashmir, North India, yet there has been no epidemiological study conducted in Kashmir, the apparently endemic area for human hydatidosis. This study was designed to determine the seroprevalence of hydatid infection in Kashmir Valley and to find out association of risk factors for acquisition of this infection. METHODOLOGY: Fourteen hundred and twenty-nine samples were collected from different districts in the Kashmir region (North India) using systematic random sampling. The 130 control samples included were from apparently healthy blood donors (100), patients with other parasitic infections (20), surgically confirmed hydatidosis patients (5), and apparently healthy subjects excluded for hydatidosis and intestinal parasitic infections (5). Hydatid-specific IgG antibody was detected by enzyme-linked immunosorbent assay, and seropositive samples were analysed further by Western blotting. RESULTS: Out of 1,429 samples, 72 (5.03%) were IgG positive by ELISA. The percentage occurrence of the highly immunoreactive antigenic fractions in IgG ELISA positive samples was 57 kDa (72.2%) followed by 70 kDa (66.7%) and 39 kDa (58.3%) by immunoblotting. Samples with other parasitic infections were reactive with the cluster of 54-59 kDa antigenic fractions. Age <15 years, male gender, contact with dog, and rural residence were the most significant factors associated with the seropositivity. CONCLUSION: The study revealed that 72 (5.03%) out of 1,429 subjects asymptomatic for hydatidosis were seropositve to E.granulosus antigen by ELISA. Western blot analysis of 72 ELISA seropositive samples showed that 66.7% and 58.3% of samples were immunoreactive with 70 and 39 kDa specific antigenic fractions, respectively. The seropositivity was significantly higher (5.79%) in the younger age group (<15 years) as compared to the 16-55 years (4.07%) and > 55 years (3.05%) age groups, suggesting ongoing transmission of this infection in the younger age group. The number of seropositive males was significantly higher as compared to females. The risk factors identified were rural residence and contact with dogs. The study suggests the presence of asymptomatic infection in subjects in Kashmir, North India, and efforts need to be made for implementation of effective prevention measures to reduce the infection burden, which may otherwise lead to symptomatology and complications in the infected subjects.

In vitro activity of antiamoebic drugs against clinical isolates of Entamoeba histolytica and Entamoeba dispar.

BACKGROUND: Amoebiasis is a major public health problem in tropical and subtropical countries. Although a number of antiamoebic agents are used for its treatment, yet the susceptibility data on clinical isolates of Entamoeba histolytica and Entamoeba dispar are not available. Therefore, the present study was aimed to assess the in vitro susceptibility of clinical isolates of E. histolytica and E. dispar to metronidazole, chloroquine, emetine and tinidazole. METHODS: A total of 45 clinical isolates (15 E. histolytica and 30 E. dispar) were maintained in polyxenic cultures followed by monoxenic cultures. In vitro drug sensitivity (IC50) of clinical isolates and standard reference strain of E. histolytica (HM1: IMSS) was assessed by nitro blue tetrazolium (NBT) reduction assay after exposure to various concentrations of each drug. RESULTS: The results showed that all clinical isolates had a higher IC50 compared to reference strain to all the four drugs. E. histolytica isolates appeared to be more susceptible [IC50 (microm) 13.2,26.3,31.2 and 12.4] compared to E. dispar isolates [IC50(microm) 15.6,28.9,32.8 and 13.2] and the reference strain of E. histolytica [IC50 (microm) 9.5, 15.5, 29.9 and 10.2] to the metronidazole, chloroquine, emetine and tinidazole respectively. CONCLUSIONS: The results indicate that till date, Entamoeba isolates in India do not seem to be resistant to the commonly used antiamoebic drugs.

Trichomonas vaginalis: random amplified polymorphic DNA analysis of isolates from symptomatic and asymptomatic women in India.

Trichomonas vaginalis, the causative agent for human trichomoniasis, is a protozoan parasite. Trichomoniasis is the most common non-viral sexually transmitted disease. The infection in women may be asymptomatic or may lead to severe vaginitis, cervicitis and severe sequelae. Despite its high prevalence, the genetic variability and factors leading to symptomatic infection have been poorly understood. One thousand women in childbearing age group were screened for the presence of T vaginalis. Thirty-eight women were found positive for T vaginalis and out of these 22 (57.9%) were having symptomatic infection and 16 (42%) were asymptomatic. Fresh isolates from 15 symptomatic and 15 asymptomatic women were axenised and subjected to random amplified polymorphic DNA (RAPD) analysis with the use of five different random primers (OPD 1-OPD 5). The isolates with similar banding pattern were assigned as a single type. OPD 3 indicated least (nine types) while OPD 4 indicated highest typing (18 types) ability. Phylogenetic analysis using RAPD distance software indicated two distinct lineages; upper branch consisting of only seven symptomatic isolates while lower branch consisting of all the 15 asymptomatic isolates the other eight symptomatic isolates were recorded in separate cluster. The study indicated that RAPD technique might be helpful to delineate the pathogenic mechanism(s) for its virulence; however, further studies on large number of isolates are desired to elucidate the findings.