The prevalence of sexually transmitted infections (STIs) and reproductive tract infections (RTIs) among hotel-based sex workers (HBSWs) in Dhaka, Bangladesh, was studied. A total of 400 HBSWs were enrolled in the study during April to July 2002. Endocervical swabs, high vaginal swabs, and blood samples from 400 HBSWs were examined for Neisseria gonorrhoeae (by culture), Chlamydia trachomatis (by PCR), Trichomonas vaginalis (by microscopy), antibody to Treponema pallidum (by both rapid plasma reagin and Treponema pallidum hemagglutination tests), and antibody to herpes simplex virus type 2 (HSV-2) (by enzyme-linked immunosorbent assay). Sociodemographic information as well as gynecological and obstetric information was collected. Among the HBSWs, 228 women (57%) were symptomatic and 172 (43%) were asymptomatic, 35.8% were positive for N. gonorrhoeae, 43.5% were positive for C. trachomatis, and 4.3% were positive for T. vaginalis. A total of 8.5% had syphilis, 34.5% were positive for HSV-2, and 86.8% were positive for at least one RTI or STI. There was no significant difference between the prevalences of STIs among the symptomatic and asymptomatic HBSWs. These data suggested a high prevalence of STIs, particularly gonorrhea and chlamydia, among HBSWs in Dhaka.As in other developing countries, sexually transmitted infections (STIs) and reproductive tract infections (RTIs) represent a major public health problem in Bangladesh (1). Control of ulcerative (syphilis, chancroid, and herpes simplex virus type 2 [HSV-2] infection) and nonulcerative (gonorrhea, chlamydia, and trichomoniasis) STIs and of RTIs (bacterial vaginosis and candidiasis) is important not only for preventing complications related to infection but also for preventing heterosexual transmission of human immunodeficiency virus (HIV). In a number of recent studies, it has been shown that bacterial and parasitic agents of STIs and RTIs, increase the release of virion particles in the semen and ulcers in the genital region and thus increase the risk of both acquisition and transmission of HIV in patients with STIs (15, 2, 4). Consistent with this observation, Grosskurth et al. have demonstrated that control of STIs through syndromic management in the general population in a rural area of Tanzania was able to reduce the serological incidence of HIV by 42% (8).Female sex workers (FSWs) are particularly at risk for STIs and HIV (5). They often are infected by their clients and subsequently transmit the infection to other partners. It has earlier been demonstrated that in most parts of Asia and Africa, 60 to 70% of the STIs relate to clients of FSWs and sexual networks (14).The number of FSWs in Bangladesh is unknown, but estimates range from 50,000 to 100,000. FSWs work in brothels, streets, hotels, and residences (7). However, in recent years there has been remarkable change in the nature of the sex industry, possibly due to (i) eviction of brothels from major cities, (ii) increased demand for sex workers in nonstigmatized locations, (iii) demand for flexible...

The prevalence of STIs/RTIs among SWs in brothels in Bangladesh is high. An intervention strategy addressing both symptomatic and asymptomatic infections and periodic screening of SWs for RTIs/STIs is essential for successful HIV and STIs prevention programs.

Vibrio vulnificus is a causative agent of serious food-borne diseases in humans related to consumption of raw seafoods. This human pathogen secretes a metalloprotease (VVP) that evokes enhancement of the vascular permeability and disruption of the capillaries. Production of microbial proteases is generally induced at early stationary phase of its growth. This cell density dependent regulation of VVP production in V. vulnificus known to be the quorum-sensing. When V. vulnificus was cultivated in Luria-Bertani (LB) medium, accumulation of the autoinducer, the signal molecule operating the quorum-sensing system, was detected. Moreover, expression of the vvp gene encoding VVP was found to be closely related with expression of the luxS gene that encode the synthase of the autoinducer precursor (luxS). These findings may indicate VVP production is controlled by the quorum-sensing system in LB medium. Furthermore, this system functioned more effectively at 26 degrees C than at 37 degrees C. When incubated at 37 degrees C in human serum supplemented with ferric chloride, production of VVP and expression of vvp increased in proportion to the concentration of ferric ion; whereas, expression of luxS was not increased. This suggests that VVP production in human serum containing ferric ion may be regulated mainly by the system other than the quorum-sensing system.

Vibrio mimicus is a potential enteric pathogen that was reported to produce diarrhea sometimes and was also found to be associated with some extra-intestinal infections namely otitis media and wound infection (10,37). It has been proposed that production of multiple toxins or toxic substances is characteristic of this species (7,20,36,38). In V. mimicus, regulation mechanisms involved in the expression of these virulence factors have not been studied yet. But expression of similar virulence factors are known to be regulated by cell density dependent regulation system, known as the quorum-sensing system, in a few other pathogenic vibrios including V. cholerae and V. vulnificus (20, 44). It is therefore very likely that V. mimicus may also possess the quorum-sensing regulation system, which might have important roles in the synchronized expression of the virulence factors of the pathogen.Cell density dependent control of cellular activities was first discovered in two luminous marine bacterial species, V. fischeri and V. harveyi (33). Later on, this phenomenon had been observed in many species of bacteria (2, 26, 43). In quorum sensing, signal molecules known as autoinducers are produced and secreted in the external environment by the bacteria. As the bacterial cell density increases the concentration of signal molecules in the surrounding environment also increases, and when it reaches the threshold level, the signal is sensed by the bacteria and then transmitted inside the cell. Signals obtained from quorum sensing, regulate expression of various genes through the function of response regulator proteins. Thus in quorum sensing, bacteria can sense their population density from the concentration of autoinducers, and accordingly expression or repression of particular genes occurs in all members of the population at a time. Namely, quorum sensing regulates processes that are effective only when a population of bacteria acts in a coordinate manner, but not when the bacteria act as individuals.Among Vibrio spp. the quorum-sensing systems of V. fischeri and V. harveyi have been most extensively studied. V. harveyi signal molecules include 3-oxo- Abstract: Presence of the quorum-sensing regulation system in Vibrio mimicus was investigated. The culture supernatants of V. mimicus strains were found to possess AI-2 autoinducer like activity, and the strains were found to harbor the genes which are homologous to luxS, luxO, and luxR of V. harveyi. These genes of V. harveyi have been shown to be important components of V. harveyi-like quorum-sensing system. The luxO gene homologue known to encode LuxO, the central component of the regulation system, was disrupted, and effects on protease and hemolysin activity were studied. Disruption of luxO gene resulted in the increased protease activity, but the hemolysin activity did not vary considerably.

Although ciprofloxacin is one of the recommended drugs of choice for the treatment of gonorrhea, in vitro resistance to this drug has been observed in surveillance studies and case reports from many parts of the world, including Bangladesh. However, to our knowledge, there have been no prospective studies of the correlation between in vitro response to the drug and treatment outcome. Therefore, a prospective study of 217 female sex workers in Dhaka, Bangladesh, was conducted to examine the correlation between the in vitro response of Neisseria gonorrhoeae and the outcome of ciprofloxacin treatment. Overall, 37.8% of the gonococcal isolates recovered from female sex workers were resistant to ciprofloxacin, and there was a good correlation between in vitro resistance and treatment failure. These findings suggest that in vitro resistance to ciprofloxacin is predictive of clinical treatment failure in patients with gonorrhea.