HIV/AIDS in India: an overview of the Indian epidemic.

The first cases of HIV infection in India were detected in 1986 among female sex workers in Chennai. A rapid increase followed in many states. The current national prevalence is about 0.26% compared with a global average of 0.2%, but the figure in most high-risk groups including female sex workers is much higher (up to 7%). New HIV infections reached a peak in 1998 and have since declined by 60%, although the total number of HIV-positive persons remains stable at 2.1 million, largely probably due to the increased life expectancy following antiretroviral therapy. The Indian epidemic is characterized by low levels in the general population and elevated concentrations among high-risk groups. Transmission is mainly heterosexually driven, with differential burdens across the states. The four main drivers of HIV infection in India differ in order from those elsewhere in the world and are commercial sex work, general heterosexual intercourse, injecting drug use and unprotected anal sex between men who have sex with men. There are distinct differences from state to state in the prevalence of HIV, with some around the national norm of 0.21% but others with over 1% infected. India has embarked on a targeted HIV prevention strategy in recent years which is strongly associated with a fall in infection rate in both low- and high-risk groups.

Undiagnosed HIV among people who inject drugs in Manipur, India.

Manipur is a geographically isolated state of India characterised by a high HIV prevalence among people who inject drugs (PWID). A low-to-moderate lifetime rate of HIV testing has been documented amongst PWID in Manipur. Little is known about the extent of undiagnosed HIV in this setting and whether uptake of HIV testing (and knowledge of a positive diagnosis) leads HIV-positive PWID to change their risk behaviours. The cross-sectional data (n = 821) analysed for this paper were collected in 2009 for the Integrated Behavioural and Biological Assessment (IBBA) using interviewer-administered questionnaires and the collection of de-linked blood and urine samples. Almost one-third (30.7%) of the participants tested HIV positive. The majority knew where to obtain a confidential HIV test (80.7%), however, half of the HIV-positive participants had either never had an HIV test (37.7%), or had undertaken a test without collecting the result (12.7%). Almost one-quarter (23.4%) of the HIV-positive participants and 17.4% of the HIV-negative participants had shared a needle/syringe with at least one other injector during the preceding month. Encouragingly, HIV-positive participants were significantly more likely than HIV-negative participants to use condoms with their regular sexual partners, however, there was still a high proportion of HIV-positive participants who did not use a condom at last sex with their regular (47.2%) or casual (48.0%) partners. Having taken an HIV test and collected the result was associated with a reduction in HIV-risk behaviours among HIV-positive participants, but not among HIV-negative participants. In conclusion, we found that a substantial proportion of the HIV-positive PWID in Manipur were not aware of their positive status, and risky injecting and sexual practices were commonplace. However, HIV-positive PWID appear to reduce their high-risk behaviours when they become aware of their HIV status highlighting the importance of taking HIV testing coverage to scale.

Sudarshan Kriya yoga improves quality of life in healthy people living with HIV (PLHIV): results from an open label randomized clinical trial.

BACKGROUND & OBJECTIVES: Improving quality of life (QOL) of healthy people living with HIV (PLHIV) is critical needing home-based, long-term strategy. Sudarshan Kriya yoga (SKY) intervention is acknowledged for its positive impact on health. It is hypothesised that SKY would improve PLHIV's QOL, justifying an evaluation. METHODS: In this open label randomized controlled pilot trial, 61 adult PLHIV with CD4 count more than 400 cells/µl and Karnofsky scale score above 70 were enrolled. Those with cardiac disease, jaundice, tuberculosis, or on antiretroviral therapy/yoga intervention were excluded. All were given standard care, randomized to SKY intervention (31: I-SKY) and only standard of care in control (30: O-SOC) arms. The I-SKY participants were trained for six days to prepare for daily practice of SKY at home for 30 min. A validated 31-item WHOQOL-HIVBREF questionnaire was used to document effect in both arms from baseline to three visits at 4 wk interval. RESULTS: Baseline QOL scores, hypertension and CD4 count were similar in both arms. An overall 6 per cent improvement of QOL scores was observed in I-SKY group as compared to O-SOC group, after controlling for baseline variables like age, gender, education and occupation ( p =0.016); 12 per cent for physical ( p =0.004), 11 per cent psychological (p =0.023) and 9 per cent level of independence (p =0.001) domains. Improvement in I-SKY observed at post-training and in the SKY adherence group showed increase in these two domains. CONCLUSIONS: A significant improvement in QOL scores was observed for the three health related QOL domains in SKY intervention arm. This low cost strategy improved physical and psychological state of PLHIV calling for upscaling with effective monitoring for sustainability of quality of life.

Differential modulation of phenotypic composition of HIV-infected and -uninfected PBMCs during cryopreservation.

This article was designed to determine variations in phenotypic composition of fresh and frozen PBMCs for assessing utility of cryopreserved PBMCs for phenotypic assays. Relative percentages of effector memory cells increased significantly as against percentages of naïve cells which showed significant decrease after cryopreservation in HIV-uninfected samples. These differences were not significant in HIV-infected individuals. There was no significant difference in the expression of activation markers in fresh and frozen PBMCs except the HLA DR expression on CD8 cells in HIV-infected individuals, which was significantly decreased in frozen PBMCs. Thus, cryopreservation resulted in differential effect on phenotypic composition of PBMCs in HIV-infected and -uninfected individuals.

The cost of safe sex: estimating the price premium for unprotected sex during the Avahan HIV prevention programme in India.

There is some evidence that female sex workers (FSWs) receive greater earnings for providing unprotected sex. In 2003, the landscape of the fight against HIV/AIDS dramatically changed in India with the introduction of Avahan, the largest HIV prevention programme implemented globally. Using a unique, cross-sectional bio-behavioural dataset from 3591 FSWs located in the four Indian states where Avahan was implemented, we estimate the economic loss faced by FSWs who always use condoms. We estimate the causal effect of condom use on the price charged during the last paid sexual intercourse using the random targeting of Avahan as an instrumental variable. Results indicate that FSWs who always use condoms face an income loss of 65% (INR125, US$2.60) per sex act compared to peers providing unprotected sex, consistent with our expectations. The main finding confirms that clients have a preference for unprotected sex and that policies aiming at changing clients' preferences and at improving the bargaining power of FSWs are required to limit the spread of HIV.

Modification of medical outcome study (MOS) instrument for quality of life assessment & its validation in HIV infected individuals in India.

BACKGROUND & OBJECTIVE: Several instruments have been developed specifically to assess the quality of life (QOL) in HIV infected individuals. No information is available in this aspect from India. The present study was thus carried out to assess the QOL among HIV infected persons, to study their relationship with socio-demographic characteristics and stages of disease progression, and to examine change in QOL over time. METHODS: One time assessment of QOL on 100 and repeat evaluation on 20 HIV infected persons enrolled in an ongoing longitudinal prospective study of clinical progression was done. Medical Outcome Study (MOS-QOL) core instrument was modified to suit the Indian cultural settings and interview-administered. RESULTS: The overall scale had Cronbach alpha 0.75. Instrument showed significant positive inter-domain correlations and linear association between QOL scores and CD4 counts. QOL was markedly affected in the domains of physical health, work and earnings, routine activities, and appetite and food intake. Women had significantly lower QOL scores despite having less advanced disease. The QOL scores decreased with drop in CD4 counts mainly in the physical health domains. Generally, the QOL scores were high in the follow up visit compared to baseline. INTERPRETATION & CONCLUSION: The modified MOS scale with Cronbach alpha of more than 0.7 and linear relationship between CD4 counts and the QOL scores indicated that the instrument was reliable and valid for evaluation of QOL in HIV infected persons in India. Comparative lower scores in the domains of physical health indicate medical intervention to greatly benefit the HIV infected persons. Longitudinal studies need to be undertaken to assess the impact of introduction of anti retroviral therapy (ART) through the national programme on disease progression and changes in QOL.

Comparing modified and plain peptide linked enzyme immunosorbent assay (ELISA) for detection of human immunodeficiency virus type-1 (HIV-1) and type-2 (HIV-2) antibodies.

Serological diagnosis of human immunodeficiency virus (HIV) based on detection of HIV antibodies is one of the easiest, cheapest and simplest assay. Synthetic peptides corresponding to immunodominant regions of envelope glycoprotein (gp41, V3 loop for HIV-1 and gp36 for HIV-2) were used in the present study, to detect the anti-HIV antibodies in sera of Sexually Transmitted Diseases (STD), Tuberculosis (TB), Anti-Natal Care (ANC) patients. About 550 serum samples were tested using Enzyme Linked Immunosorbent Assay (ELISA) technique. The human sera positive for antibody to HIV-1 and HIV-2, reacted to different degrees with these peptides when used as a plain peptide with or without CGG motif/biotin motif at the amino terminus. The selected sequences are of Indian strain with 'C' serotype. The results showed a 100% sensitivity and specificity for V3 loop peptide and 98% sensitivity and specificity for gp41 peptide containing CGG moiety while the plain peptides showed similar sensitivities but low specificity's, i.e. 98% for V3 loop peptide and 42% for gp41 peptide when reacted with HIV-1 positive sera. The presence of biotin at the amino terminus did not provide any beneficial effect in increasing the sensitivity although the specificity was enhanced for both the peptide sequences, i.e. gp41 and V3 loop peptide. Furthermore, the gp36 peptide containing CGG moiety detected the HIV-2 sera with 100% sensitivity and 98% specificity while the sensitivity and specificity of gp36 plain peptide was reduced to 98 and 90%. Thus the study overall highlighted the importance of synthetic peptides containing CGG moiety as a capture antigen in detecting both HIV-1 & 2 sera using an indigenously built ELISA system which is simple, cheap, sensitive and cost effective for rural areas.

Sensitivity and specificity of rapid HIV testing of pregnant women in India.

OBJECTIVE: Efforts to prevent HIV transmission from mother to infants in settings like India may benefit from the availability of reliable methods for rapid and simple HIV screening. Data from India on the reliability of rapid HIV test kits are limited and there are no data on the use of rapid HIV tests for screening of pregnant women. METHODS: Pregnant women attending an antenatal clinic and delivery room in Pune agreed to participate in an evaluation of five rapid HIV tests, including (a) a saliva brush test (Oraquick HIV-1/2, Orasure Technologies Inc.), (b) a rapid plasma test (Oraquick HIV-1/2) and (c) three rapid finger prick tests (Oraquick HIV-1/2; HIV-1/2 Determine, Abbott; NEVA HIV-1/2 Cadila). Results of the rapid tests were compared with three commercial plasma enzyme immunoassay (EIA) tests (Innotest HIV AB EIA, Lab systems/ELISCAN HIV AB EIA, UBI HIV Ab EIA). RESULTS: Between September 2000 and October 1, 2001, 1258 pregnant women were screened for HIV using these rapid tests. Forty-four (3.49%) of the specimens were HIV-antibody-positive by at least two plasma EIA tests. All of the rapid HIV tests demonstrated excellent specificity (96-100%). The sensitivity of the rapid tests ranged from 75-94%. The combined sensitivity and specificity of a two-step algorithm for rapid HIV testing was excellent for a number of combinations of the five rapid finger stick tests. CONCLUSION: In this relatively low HIV prevalence population of pregnant women in India, the sensitivity of the rapid HIV tests varied, when compared to a dual EIA algorithm. In general, the specificity of all the rapid tests was excellent, with very few false positive HIV tests. Based upon these data, two different rapid HIV tests for screening pregnant women in India would be highly sensitive, with excellent specificity to reliably prevent inappropriate use of antiretroviral therapy for prevention of vertical HIV transmission.

Production & characterization of monoclonal antibodies to Mycobacterium tuberculosis.

BACKGROUND & OBJECTIVES: Monoclonal antibodies (MAbs) against Mycobacterium tuberculosis H37Rv culture filtrate (CF) were raised by immunizing BALB/c mice and characterization was done. Attempts have been directed towards identifying mycobacterial antigens in biological fluids by employing polyclonal and monoclonal antibodies specific for M. tuberculosis. Immunohistologic studies, using MAbs for the localization of whole or fragmented bacilli in the biopsy specimens were also carried out. METHODS: Intrasplenic IS and intraperitoneal i.p. routes of immunization, were compared. The MAbs were characterized for their isotype, binding specificity, nature of binding epitope, reactivity in immunoassays etc. RESULTS: IS and i.p. routes of immunization, were compared and i.p. was found superior. Ten MAbs designated TRC 1-10 were produced. Of these, 7 MAbs, TRC 1-7 reacted with the 30/31 kDa doublet (antigen 85 complex), TRC 8 with 12 kDa in addition to 30/31 kDa and TRC 9 and 10 with the 24 and 12 kDa antigens respectively. Six MAbs were classified as broadly cross reactive and 2 showed limited cross reactivity. TRC 8 and 10 showed species specificity. Employing TRC 8 in sandwich ELISA, antigen was detected in sera from 17 of 25 pulmonary tuberculosis patients and 3 of 20 controls. TRC 8 was found to be useful in detecting antigens specifically in M. tuberculosis and M. leprae infected tissues, by immunoperoxidase staining. INTERPRETATION & CONCLUSION: TRC 8 was found to be restricted in its reactivity to M. tuberculosis complex and M. leprae. TRC 8 may prove useful in immuno-diagnosis of tuberculosis.

Preliminary observations on lymphocyte subpopulations in HIV seropositive & HIV seronegative tuberculosis patients in Pune, India.

CD4 and CD8 lymphocyte counts were determined in 59 HIV seropositive and 41 HIV seronegative newly diagnosed tuberculosis patients in Pune. There were significant differences in the CD4 counts and CD4/CD8 ratios between HIV seropositive and HIV seronegative tuberculosis patients. Majority of the HIV seropositive patients had a CD4 count less than 500 cells/cu.mm, whereas among the HIV seronegative patients, majority had a CD4 count more than 500 cells/cu.mm. In HIV seropositive patients with extrapulmonary and pulmonary tuberculosis, the CD4 counts were lower than in those who had only pulmonary or extrapulmonary tuberculosis. There was no significant differences in the CD8 counts between HIV seropositive and HIV seronegative tuberculosis patients, except for patients with pulmonary cavity, where the CD8 counts were significantly higher in HIV seropositive tuberculosis patients. In HIV seropositive individuals with pulmonary tuberculosis, the CD8 counts in those with pulmonary cavity were higher than in those without any pulmonary cavity. Absence of cavitation and presence of pulmonary with extrapulmonary tuberculosis occurred when immune activation was at a lower level.

Cross-reactive HIV-1-specific CTL in recent seroconverters from Pune, India.

In the light of the diversity of HIV, matching the genotype of candidate HIV vaccines with the transmitted genotype may be required. Alternatively, matching the immunotype of HIV vaccines and transmitted subtypes may be the best option. Since studies of cross-subtype HIV-1 immunity are limited, subtype B specific cytolytic T lymphocyte (CTL) responses were measured in subtype C infected individuals. HIV-1 subtype B-specific CTLs, plasma viral load and absolute CD4 and CD8 lymphocyte numbers were measured in six HIV-1 subtype C infected individuals within a year of seroconversion. HIV-1 subtype B env. gag and nef-specific CTL precursor frequencies were measured by limiting dilution analysis. Three of the six subjects had demonstrable CTL directed at more than one HIV-1 subtype B antigens. One individual demonstrated CTL directed against all three HIV-1 subtype B antigens, while two individuals did not demonstrate CTL against HIV-1 subtype B antigens. The frequencies of CTL precursor were not associated with plasma viral load or absolute CD4 cell counts in peripheral blood. These findings suggest that some individuals recently infected with subtype C HIV-1 generate cross-reactive CTL that are directed against HIV-1 subtype B.

Increasing trend of HIV seroprevalence among pulmonary tuberculosis patients in Pune, India.

A total of 4618 tuberculosis patients attending the TB clinic at the Sassoon General Hospitals, Pune between 1991 and 1996 were screened for anti-HIV antibodies. Of these 694 were found reactive in enzyme immuno assay (EIA) and 624 were further confirmed by a second test, either rapid EIA or Western blot. HIV-1 reactivity was predominant among tuberculosis patients with HIV-2 reactivity appearing only in 1995. HIV-2 seroreactivity accounted for 0.54 and 1.02 per cent of all HIV reactive samples in 1995 and 1996. HIV-1 and HIV-2 dual reactivity accounted for 1.63 and 2.04 per cent of all infections in 1995 and 1996. The overall seroprevalence of HIV among newly diagnosed tuberculosis patients rose from 3.2 per cent in 1991 to 20.1 per cent in 1996.

PIP: A total of 4618 tuberculosis (TB) patients attending the TB clinic at the Sassoon General Hospitals, Pune, India, between 1991 and 1996 were screened for anti-HIV antibodies. Of these, 694 were found reactive in enzyme immunoassay (EIA) and 624 were further confirmed by a second test, either rapid EIA or Western blot. HIV-1 reactivity was predominant among tuberculosis patients, with HIV-2 reactivity appearing only in 1995. HIV-2 seroreactivity accounted for 0.54% and 1.02% of all HIV reactive samples in 1995 and 1996. HIV-1 and HIV-2 dual reactivity accounted for 1.63% and 2.04% of all infections in 1995 and 1996. The overall seroprevalence of HIV among newly diagnosed tuberculosis patients rose from 3.2% in 1991 to 20.1% in 1996.

Isolation & preliminary characterization of two HIV-2 strains from Pune, India.

Two HIV-2 strains were isolated from peripheral blood mononuclear cells of two HIV-2 seropositive patients with pulmonary tuberculosis by co-cultivating the cells with phytohaemagglutinin-P stimulated heterologous normal lymphocytes. Biological characterization of the isolates indicated that both isolates were syncytium inducing and induced cytopathic effect in the form of giant cells and syncytia formation in four T lymphoid cell lines. The isolates differed in their replication pattern. The isolates were confirmed as HIV-2 by nested PCR using HIV-1 and HIV-2 specific oligonucleotide primers from the env region and by supplementary tests like indirect immunofluorescence assay, syncytium inhibition assay using reference and HIV-2 reactive patients' sera, western blot and electron microscopy. Neutralization of one isolate (TB1) with two Senegal reference sera also indicated that the isolate may be related to the Senegal strain. To our knowledge, this is the first report of isolation of HIV-2 in India.

Evidence for high prevalence & rapid transmission of HIV among individuals attending STD clinics in Pune, India.

Prevalence and incidence of HIV-1 infection among persons attending two STD clinics in Pune between May 1993 and October 1995 are reported. On screening 5321 persons, the overall prevalence of HIV-1 infection was found to be 21.2 per cent, being higher in females (32.3%) than in males (19.3%). Analysis of behavioural and biological factors showed that old age, sex work, lifetime number of sexual partners, receptive anal sex, lack of circumcision, genital diseases and lack of formal education were related to a higher HIV-1 seroprevalence. The observed incidence rate of 10.2 per cent per year was very high, much higher in women than in men (14.2% and 9.5% per year respectively) and over three times higher among the sex workers. Females in sex work, males having recent contacts with female sex workers (FSWs) and living away from the family and persons with previous or present genital diseases had a higher risk of seroconversion. Condom usage was shown to have a protective effect in seroprevalence and seroincidence analysis. With limited available resources and lack of a suitable vaccine or a drug, long-term prevention policy of creating awareness in the community must be supplemented by strengthening STD control measures and promotion of condom use and safe sex. Factors related to availability and utilization of condoms must be carefully investigated.

Relationship between clinical conditions and CD4 counts in HIV-infected persons in Pune, Maharashtra, India.

BACKGROUND: A decade after the detection of human immunodeficiency virus (HIV) infection in India, a steady increase in the number of patients with acquired immunodeficiency syndrome (AIDS) has been observed. The therapeutic options for patients with AIDS in developing countries include chemoprophylaxis and identifying and treating opportunistic infections. CD4 counts help in clinical monitoring and making decisions about initiating antiretroviral therapy or chemoprophylaxis. Flowcytometry is expensive and available only at specialized laboratories. Therefore, the possibility of using clinical indicators to predict low CD4 counts and disease progression needs to be explored. METHODS: This cross-sectional study was conducted among 137 HIV-infected persons investigated at an HIV reference centre in Pune. The study methods comprised pre-test counselling, informed consent, blood withdrawal and clinical evaluation. Serum samples were tested for HIV and CD4 counts were estimated on FACSort. RESULTS: Study participants commonly reported with oral candidiasis, herpes zoster, pulmonary tuberculosis, lymphadenopathy, weight loss, rash, diarrhoea and fever. CD4 counts were significantly lower among men, symptomatic patients and those with oral candidiasis, weight loss and multiple clinical conditions. The sensitivity of most of the clinical conditions was low, the specificity was high and the positive predictive value of oral candidiasis and weight loss for low CD4 counts was > 75%. CONCLUSION: The presence of oral candidiasis and weight loss were highly predictive of low CD4 counts and these can be considered as markers of HIV disease progression. Absence of clinical conditions was found to be a good predictor of high CD4 counts. Larger systematic natural history studies may help in identifying clinical conditions that could have a prognostic significance among HIV-infected people.

Risk factors for HIV infection in people attending clinics for sexually transmitted diseases in India.

OBJECTIVE: To investigate the risk factors for HIV infection in patients attending clinics for sexually transmitted diseases in India. DESIGN: Descriptive study of HIV serology, risk behaviour, and findings on physical examination. SUBJECTS: 2800 patients presenting to outpatient clinics between 13 May 1993 and 15 July 1994. SETTING: Two clinics and the National AIDS Research Institute, in Pune, Maharashtra State, India. MAIN OUTCOME MEASURE: HIV status, presence of sexually transmitted diseases, and sexual behaviour. RESULTS: The overall proportion of patients infected with HIV was 23.4% (655/2800); 34% (184) of the women and 21% (459) of the men were positive for HIV infection. Of the 560 women screened, 338 (60%) had a reported history of sex working, of whom 153 (45%) were infected with HIV-1. The prevalence of HIV-1 infection in the 222 women who were not sex workers was 14%. The significant independent characteristics associated with HIV infection based on a logistic regression analysis included being a female sex worker, sexual contact with a sex worker, lack of formal education, receptive anal sex in the previous three months, lack of condom use in the previous three months, current or previous genital ulcer or genital discharge, and a positive result of a Venereal Disease Research Laboratory test. CONCLUSIONS: In India the prevalence of HIV infection is alarmingly high among female sex workers and men attending clinics for sexually transmitted diseases, particularly in those who had recently had contact with sex workers. A high prevalence of HIV infection was also found in monogamous, married women presenting to the clinics who denied any history of sex working. The HIV epidemic in India is primarily due to heterosexual transmission of HIV-1 and, as in other countries, HIV infection is associated with ulcerative and non-ulcerative sexually transmitted diseases.

PIP: During May 1994-July 1995 in India, health workers at two clinics for sexually transmitted diseases (STDs) in Pune provided HIV serological screening and a physical examination to 2800 patients who completed a questionnaire, so that researchers could identify risk factors for HIV-1 infection in this high-risk population. 60% of the female STD patients were sex workers. 90% of the men had contact with a sex worker within the last 3 months. 14% of all STD patients were women who were not sex workers. 82% of these were married and monogamous. 13% of the married and monogamous women tested positive for HIV-1. Overall, 23.4% of all STD patients tested positive for HIV-1. Only 24% of all STD patients had used condoms during the last 3 months. The leading clinical diagnosis was chancroid (33% for men and 20% for women). The logistic regression analysis showed that the risk factors for HIV-1 infection were: being a sex worker (odds ratio [OR] = 3.7; p 0.001), contact with a sex worker (OR = 1.71; p = 0.01), receptive anal sex (OR = 3.52; p 0.001), tattooed after 1985 (OR = 1.31; p = 0.01), current or previous genital ulcer (OR = 1.29; p = 0.01), and a positive result of a Venereal Disease Research Laboratory test (OR = 1.33; p = 0.01). Protective factors were some formal education (OR = 0.76; p = 0.02), and condom use (sometimes/always, OR = 0.75; p = 0.03). These findings indicate a need for comprehensive and national STD services in India to control STDs and a health education campaign on HIV/AIDS to reduce high risk behavior.

Syphilis infection among female sex workers in Nagaland, Northeast India: analysing their vulnerability to the infection.

This paper describes the sex work characteristics and factors associated with syphilis among female sex workers (FSWs) in Dimapur district of high HIV prevalence Indian state, Nagaland. The study recruited 426 FSWs in 2006 using respondent-driven sampling. The prevalence of syphilis was 21.1% and HIV prevalence was 11.7%. Approximately half were under 25 years of age. Clients were solicited mainly in public places (32.7%), while hotels/lodges/rented rooms were the most common places of entertainment (57.2%). Condom use during the last sex was 36.5% with occasional and 27% with regular clients. Being married, being widowed/divorced/separated, being illiterate or having a history of drug use increased the likelihood of syphilis infection. Entertaining clients in bars/booze joints decreased the probability of syphilis. FSWs who moved between soliciting in public places or bars/booze joints and then entertaining in hotels/lodges/rented rooms had a higher vulnerability to syphilis. In summary, we found that the vulnerability to syphilis among mostly young FSWs in Dimapur varied according to their sex work characteristics, marital and educational status and drug use habits. They may be more vulnerable to HIV and sexually transmitted infections (HIV/STIs) due to the low rate of condom use. The findings have direct implications for HIV/STI prevention programmes in Northeast India.