Parimi Prabhakar

High rates of reinfection and incidence of bacterial sexually transmitted infections in a cohort of female sex workers from two Indian cities: need for different STI control strategies?

Background Female sex workers (FSWs) in India are provided a standardised package of clinical interventions for management of sexually transmitted infections (STIs). A study was conducted among FSWs at known high STI prevalence sites to determine the effectiveness of the service package. Methods A cohort of FSW clinic attendees in two cities, Hyderabad and Mumbai, were enrolled and followed up from October 2008 to November 2009. At each visit, behavioural and clinical data were obtained and vaginal swabs collected for laboratory testing of cervical infections (gonorrhoea and chlamydia). Results 417 participants were enrolled, of whom 360 attended at least a follow-up visit. Prevalence of cervical infections did not change between the baseline and final visits (27.7% and 21.3% respectively, p=0.08) in spite of presumptive treatment at baseline and syndromic management at all visits. The proportion of asymptomatic cervical infections increased from 36% at baseline to 77% at the final visit. Incidence rate of cervical infections was high (85.6/100 person years) and associated with a prevalent cervical infection at baseline (HR=2.7, p<0.001) and inconsistent condom use with non-commercial partners (HR=2.5, p=0.014). Conclusions High rates of STIs persisted despite the interventions due to poor condom use, minimal partner treatment, and high prevalence and incidence of STIs with a large proportion of asymptomatic infections. High-prevalence FSW sites in India need to design more effective partner treatment strategies and consider increasing the frequency of presumptive treatment as a temporary measure for quickly reducing STI prevalence, with renewed emphasis on consistent condom use with all partners.

Biological false positive serological tests for syphilis in the Jamaican population.

A total of 19,067 sera were screened for biological false positive (BFP) reactivity by the Venereal Disease Research Laboratory (VDRL) test. Sera which were reactive in the VDRL test were confirmed by the fluorescent treponemal antibody absorption (FTA-ABS) test. BFP reactions were detected in 0.59% of the general population, 0.72% of pregnant women and 11.8% of patients with systemic lupus erythematosus (SLE). The rate of BFP reactors among pregnant women did not differ significantly from the general population. The female to male ratio of BFP in the general population was 2:1 whilst that in the group of patients with SLE was 8:1. The overall seroprevalence of syphilis was 2.2%.

Characteristics of Staphylococcus aureus Strains Isolated from Clinical and Non-clinical Human Sources in Trinidad: Susceptibility to Bacteriophages and Antimicrobial Agents, and Toxigenicity

The susceptibility of Staphylococcus aureus strains isolated from human clinical and non-clinical sources in Trinidad to bacteriophages and antimicrobial agents was determined. The ability of the strains to produce enterotoxins and toxic shock syndrome toxin-1 (TSST-1) was also investigated. Of the 554 strains tested, 454 (81.8%) were susceptible to international phage set (IPS) phages with strains isolated from bacteruria (57.1%) and bacteremia (53.3%) having a low sensitivity compared to isolates from aspirates (87.3%) and anterior nares (97.4%). All sources combined, strains were most susceptible to phages belonging to several groups (mixed). Overall, 419 (75.6%) strains were resistant to one or more of nine antimicrobial agents tested. Resistance to penicillin was most prevalent, with 413 (74.5%) strains found to be resistant. Prevalence of resistance to tetracycline, gentamicin, oxacillin, cefuroxime and ciprofloxacin was 5.1%, 2.0%, 0.7%, 0.4% and 0.4%, respectively. Of the 554 strains tested, 307 (55.4%) produced staphylococcal enterotoxins A (SEA), B (SEB), C (SEC) and D (SED) singly or in combination. Strains recovered from high vaginal swabs were least enterotoxigenic (40.0%) as compared to umbilical infection isolates which were most enterotoxigenic (78.9%). TSST-1 was produced by 95 (19.0%) out of 499 strains tested, with isolates from bacteruria found to be most toxigenic (33.3%). It was concluded that the S. aureus strains tested were highly susceptible to bacteriophages and antimicrobial agents (except penicillin) and that enterotoxigenic and TSST-1 producers were widespread and have an aetiologic potential.

Alteration in sample preparation to increase the yield of multiplex Polymerase Chain Reaction assay for diagnosis of genital ulcer disease.

PURPOSEnGenital Ulcer Disease (GUD) is common sexually transmitted infection (STI). Multiple studies have shown that GUDs are strongly associated with the transmission and the acquisition of HIV infection. An accurate diagnosis of common etiology of GUD namely Herpes, syphilis and Chancroid is possible using Multiplex PCR (M-PCR). However, frequent presence of Polymerase Chain Reaction inhibitors in the ulcer swab specimen limits the performance of the assay. In order to overcome this problem, alternative specimen preparation method was used.nnnMATERIALS AND METHODSnTo determine the common etiology, GUD specimens obtained under an STI operations research study were tested with M-PCR after the samples were prepared using Roche Amplicor specimen preparation kit. PCR inhibiting samples were identified from that, which showed negative results. These samples were subjected to phenol-chloroform extraction and ethanol precipitation before the conduct of M-PCR on them.nnnRESULTSnOf the 237 GUD specimens tested, in 145 etiologies could be detected, whereas 92 samples were found negative. Further spiking with one of the target DNA, 128 of the negative samples were found to contain the inhibitors. These 126 samples were then subjected to phenol chloroform extraction and ethanol precipitation followed by M-PCR. Using this method for sample preparation, etiology could be determined in 46 (23%) additional samples. This success rate of altered sample preparation method has been lower than that has reported.nnnCONCLUSIONnThe results indicate that sample preparation using phenol chloroform extraction and ethanol precipitation, prior to M-PCR helps to eliminate the inhibitors and increase the yield of the assay. However, being a laborious procedure, it may be used for samples giving negative results after the screening by Roche Amplicor specimen preparation kit.

P5-S6.19 Prevalence and incidence of sexually transmitted infections among female sex workers in two cities in India: implications for STI control strategies

Background India is a large country with marked heterogeneity in prevalence of sexually transmitted infections (STIs) which has implications for STI control strategies. The study objective was to measure the prevalence and incidence of common bacterial STIs in a cohort of female sex workers (FSWs) in known high STI prevalence cities in response to a package of standardised interventions under Avahan, the India AIDS Initiative of the Bill & Melinda Gates Foundation. Methods FSWs attending clinics were followed up periodically over 6–9u2005months. At every visit, vaginal swabs were tested for Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) by Gen-Probe APTIMA Combo II. During the baseline and final visits, vaginal swabs were tested for Trichomonas vaginalis (TV) by PCR and blood was tested for syphilis using Rapid Plasma Reagin (RPR) with confirmatory Treponema pallidum Haemagglutination Assay (TPHA). All participants received presumptive treatment for gonorrhoea and chlamydia at the baseline visit and syndromic STI management at all subsequent visits. Results A total of 417 FSWs were recruited, 360 returned for at least one follow-up visit, and 282 completed the final visit. The total follow-up period was 109.4 person years (median 0.18u2005years, maximum 1.07u2005years). Self-reported consistent condom use with commercial and regular partners was 70% and 17%, respectively. A substantial proportion of cervical and trichomonal infections were asymptomatic (see Abstract P5-S6.19 table 1). The incidence of GC/CT and TV was 1.0 and 2.0 per person year respectively. Three new cases of latent syphilis were detected at the final visit. Abstract P5-S6.19 Table 1 Prevalence of STIs and asymptomatic infections (n=282) Pathogen Baseline visit 1st follow-up Final visit Cervical infections (GC and/or CT) 27.7% (asymptomatic 35.9%) 16.7% (asymptomatic 60.5%) 21.3% (asymptomatic 76.7%) TV 29.9% (asymptomatic 27.2%) 46.6% (asymptomatic 82.2%) Latent syphilis (RPR titre >1:8) 6.8% 2.5% Conclusions The incidence of GC, CT and TV and the considerable burden of asymptomatic infections indicate the need for periodic presumptive treatment at high STI prevalence sites in India. The current regime of bi-annual syphilis screening is justified. Consistent condom use and partner treatment, particularly for regular partners, need to be re-emphasised.

P5-S3.03 Individual tracking among high risk groups for STI management in India: an analysis of 400 000 high risk groups followed from 2004 to 2009

Background Avahan, the India AIDS Initiative of the Bill & Melinda Gates Foundation implemented a large HIV prevention program across six high HIV prevalence states among high risk groups (HRG) consisting of female sex workers (FSW), high risk men who have sex with men (HR-MSM), transgender (TG) and injecting drug users (IDU) in India. Methods The Avahan monitoring system included individual tracking data pertaining to registration, outreach and clinical services among HRG. All clinic visits were recorded using unique identification numbers, and visits by each clinic attendee were tracked from January 2004 to December 2009. Each clinic visit was recorded using a pre-defined clinical encounter form (CEF). Results A total of 439u2008000 individuals (including 331u2008616 FSW, 10u2008280 IDU, 82u2008246 H- MSM, and 7330 TG) visited the clinics with a total of 2u2008716u2008391 visits. Individuals made an average of 6.2 visits to the clinics during the study period. The number of visits per person increased annually from 1.2 in 2005 to 8.3 in 2009. The proportion of attendees visiting clinics more than four times a year increased from 4% in 2005 to 26% in 2009 (p<0.001). The proportion of syndromes diagnosed among FSW decreased from 39% in 2005 to 11% in 2009 (p<0.001) while the proportion of syndromes diagnosed among HR-MSM decreased from 11.6% to 3.5 % (p<0.001). The proportion of attendees seeking regular STI check-ups increased from 12% to 48% (p<0.001). The proportion of HRG accessing clinics within 2u2005days of the onset of STI-related symptoms and acceptability of speculum and proctoscope examination increased significantly (p<0.001) see Abstract P5-S3.03 figure 1. Conclusions The project demonstrated that acceptable and accessible services with marginalised and often difficult-to-reach populations can be brought to a very large scale using standardised approaches. The paper presents the utilisation of these services, improved health seeking behaviour and reduced STI syndromes among the HRG. Abstract P5-S3.03 Figure 1 Decreasing trends of STI syndromes in the Avahan clinics Jan 2005 to June 2009.