Vaginal douching and association with sexually transmitted infections among female sex workers in a prefecture of Yunnan Province,China

Abstract

Summary

Vaginal douching is a common practice and has been hypothesised to increase a woman's risk for human of contracting HIV and sexually transmitted infections (STIs). Our objective was to assess the prevalence of douching and its association with STIs, genital symptoms and HIV/STI knowledge among female sex workers (FSWs). We conducted a cross-sectional study of 837 FSWs with interviews and laboratory tests for HIV/STIs in a prefecture of Yunnan Province in southern China. Vaginal douching was reported by 84% of the women. We found a higher prevalence of vaginal douching practice among FSWs of Han ethnicity, and who were single or cohabitating. Douching was also significantly more common among more educated FSWs and those with greater knowledge of HIV/STIs, and as well as in FSWs who had experienced clinical symptoms in the previous 12 months. Douching was linked to higher risks of HIV (adjusted odds ratio = 2.29; 95% confidence interval 1.01–5.23) and herpes simplex virus type 2 infections (adjusted odds ratio = 2.18; 95% confidence interval 1.46–3.24) after adjusting for confounding factors. Medical professionals and public health workers should correct women's misconception about the effectiveness of douching and discourage women from douching through educational activities. More prospective studies among FSWs are urgently required to identify the relationship between vaginal douching and HIV/STIs.

Keywords

Vaginal douching female sex workers human immunodeficiency virus sexually transmitted infections China

Introduction

There is growing evidence about the importance of female sex workers (FSWs) and their clients as bridging groups to the general population and drivers of the human immunodeficiency virus (HIV) epidemic in China.^1,2 Since the early 1980s when commercial sex reemerged in mainland China after two decades of virtual extinction, prostitution has developed into a widespread industry due to rapid economic development, large income disparities, limited employment opportunities for women, a higher proportion of men than women in the population, and changing notions of sexuality.^3–5 The number of women engaging in commercial sex in mainland China has been estimated to range from four to ten million.^6–8 Several studies in China have revealed a high prevalence of HIV and other sexually transmitted infections (STIs) among FSWs.^9–11 Although the role of ulcerative and non-ulcerative STIs in facilitating the transmission of HIV is well established, the role of local genital tract factors in HIV transmission is unclear.

Vaginal douching is the practice of cleaning the vagina with liquid agents for hygienic and/or therapeutic purposes.¹² Many women douche before or after sexual intercourse for alleviating odour and preventing STIs or pregnancy. However, there is some evidence that frequent vaginal douching may increase women's susceptibility to sexually transmitted agents, through modification of the vaginal flora. Several studies have linked vaginal douching to an increased risk for STIs,^13,14 pelvic inflammatory disease (PID),¹⁵ cervical infections¹⁶ and other gynecologic health problems.¹⁷ Because genital tract infections such as cervicitis and PID have, in turn, been identified as risk factors for HIV acquisition, vaginal douching may have both direct and indirect roles in the heterosexual transmission of HIV.

HIV/STIs prevalence amongst FSWs are among the highest levels in Yunnan Province in southern China, near the borders with Vietnam, Thailand, and Myanmar.¹⁸ In our evaluation of FSWs in Yunnan Province, we found them to be routinely cleansing the vaginal and vulvar area before or after sex with clients or partners, using agents such as soaps and toothpastes. This study was undertaken to assess the association between vaginal douching and STIs, genital symptoms, and knowledge of HIV/STIs among a group of FSWs in a prefecture of Yunnan Province, China.

Subjects and methods

This study was conducted by the Chinese Center for Disease Control and Prevention (China CDC) in Beijing in conjunction with provincial and local CDC staff in Yunnan. With approval from both the national and local Yunnan institutional review boards, we conducted a cross-sectional study among FSWs in a prefecture of Yunnan Province from March to May 2012. The inclusion criteria for the study were age ≥16 years, self-reported to have sold sex for money within the previous three months, and agreement to testing and counselling for HIV, for other STIs and for use of illegal drugs. Every study participant was informed of the study's purpose, procedures, risks, and benefits of participation in study screening. After providing informed consent, participants were asked standardised questions about their demographics, basic medical history, and vaginal douching practice by means of a 14-page self-administered structured questionnaire which was developed by our study team. Vaginal douching was defined as the practice of cleansing the vagina with a liquid solution.

Blood was collected and tested for HIV-1 antibodies (enzyme-linked immunosorbent assay [ELISA], Vironostika HIV Uni-Form plus O, bioMerieux, Holland), herpes simplex virus type 2 antibody (HSV-2, HerpeSelect-2 ELISA IgG, Focus, USA), and syphilis (rapid plasma reagin [RPR] test, Diagnosis kit, Xinjiang Xindi company, China). Positive HIV-1 ELISAs were confirmed by Western blot (Diagnostics HIV Blot 2.2, Genelabs, USA) and positive RPR tests for syphilis were confirmed by the Treponema pallidum particle agglutination (TPPA) test (Serodia-P·PA-Fujirebio, Fuji, Japan). Endocervical swabs were collected and tested for Neisseria gonorrhoeae and Chlamydia trachomatis by polymerase chain reaction (PCR, AMPLICOR, Roche, USA). Vaginal swabs were collected and a wet mount prepared to detect Trichomonas vaginalis. Finally, urine was collected for opiate screening (MOP One Step Opiate Test Device, ACON Laboratories, Inc., USA). Participants were classified as using non-injected illegal drugs if they either self-reported using them or tested urine positive for opiates; injected drug use status was based only on self-report. All participants were scheduled for a follow-up visit four weeks later to discuss test results and for counselling.

Statistical tests were performed using SAS™ 9.1 software (SAS Institute Inc, Cary, NC, USA). Chi square tests were used to evaluate the relationship between vaginal douching practice and STIs. Univariate associations between vaginal douching practice and socio-demographics, behavioural characteristics, HIV/STI-related knowledge, and perceived symptoms in the previous 12 months were evaluated using simple logistic regression analysis. A multivariate logistic regression model was used to evaluate the relationship between vaginal douching and HIV/STIs. All statistical tests were conducted based on two-tailed alternatives with the significance level set at p < 0.05. Higher risk venues were defined as locations where FSWs generally charged less than 100 yuan (about $16 USD) for sex services, including beauty salons, temporary sublets, and street walkers; these FSWs attracted the less wealthy and less educated clients potentially at higher risk of HIV infection, such as drug users. Lower risk venues were defined as locations where FSWs generally charged 100 yuan or more for sex, including karaoke clubs, night clubs, saunas, and hotels; these FSWs attracted a wealthier, better educated clientele.

Results

Demographics of the study population

Of the 854 FSWs recruited for the study, 837 met the inclusion criteria and were enrolled. Seventeen subjects were not enrolled because they reported that they had not sold sex for money in the previous three months. Of the subjects enrolled, 833 provided all study specimens. 428 (51%) returned for test results and post-test counselling.

Table 1 describes demographic characteristics and their association with vaginal douching practice. These women were predominantly young with a median age of 23 years (interquartile range [IQR] 19–28 years), of Han ethnicity with permanent residences in Yunnan. Although women aged 21–25 years tended to be more likely to report douching in contrast to FSWs aged 16–20 years, those aged ≥ 26 years were significantly less likely to report douching (odds ratio [OR] = 0.43; 95% confidence interval [CI] 0.22–0.86). Women of minority ethnicity were 66% as likely as Han ethnicity to douche (OR = 0.66; 95% CI 0.45–0.96). Women with ≥ 9 years of formal education were significantly more likely to douche (OR = 1.58; 95% CI 1.07–2.32). In contrast to women whose marital status was single or cohabitation, those whose marital status was married, separated, divorced, or widowed were significantly less likely to report douching (OR = 0.66; 95% CI 0.45–0.97).

Table 1.

Demographic characteristics of FSWs by vaginal douching practice.

Characteristics		Douchers N (%)	Non-douchers N (%)	OR (95% CI)	p Value
Age (years)	16–20	470 (84.2)	88 (15.8)	1.0
	21–25	202 (85.6)	34 (14.4)	1.11 (0.72–1.71)	0.63
	26–52	30 (69.8)	13 (30.2)	0.43 (0.22–0.86)	0.02
Ethnicity	Han	464 (85.9)	76 (14.1)	1.0
Ethnicity	Minority	238 (80.1)	59 (19.9)	0.66 (0.45–0.96)	0.03
Registered permanent residence	Outside Yunnan	133 (83.1)	27 (16.9)	1.0
	Other cities in Yunnan	302 (83.2)	61 (16.8)	1.01 (0.61–1.65)	0.99
	Kaiyuan city	267 (85.0)	47 (15.0)	1.15 (0.69–1.93)	0.33
Education level	<9 years	381 (81.2)	88 (18.8)	1.0
Education level	≥9 years	321 (87.2)	47 (12.8)	1.58 (1.07–2.32)	0.02
Marital status	Single or cohabitation	506 (85.6)	85 (14.4)	1.0
Marital status	Married, separated, divorced, or widowed	196 (79.7)	50 (20.3)	0.66 (0.45–0.97)	0.03
Residence type	Apartment	422 (84.4)	78 (15.6)	1.0
	Family home	51 (81.0)	12 (19.0)	0.79 (0.40–1.54)	0.48
	Brothel or other working location	229 (83.6)	45 (16.4)	0.94 (0.63–1.40)	0.76
Entertainment venue	Lower risk	460 (83.9)	88 (16.1)	1.0
Entertainment venue	Higher risk	242 (83.7)	47 (16.3)	0.99 (0.67–1.45)	0.66

FSWs: Female sex workers.

Reasons for and agents used in vaginal douching

Vaginal douching was very common among these FSWs, with 702 (83.9%) reporting ever douching using any products. The types of agents used varied, but 89.9% of FSWs reported ever douching with medical disinfectant, followed by 58.1% with water only, 27.9% with toothpaste, 16.7% with salt water, 4.0% with spermicide, 3.0% with soapy water, and 0.9% with vinegar. Many reported multiple reasons for douching, but 79.3% indicated ‘to feel cleaner’ was an important indication, with 77.5% for preventing disease, 36.3% for cleaning vaginal discharge, 27.4% for curing or preventing odour, 12.3% for preventing pregnancy, and 7.3% for cleaning during menstruation.

Association between douching and behavioural characteristics, HIV/STI knowledge

Forty-nine percent of women reported a ‘regular sex partner’, defined as a man with whom she had regular sexual relations without compensation, such as a boyfriend or spouse. Of the subjects who said they had a regular sex partner, 84% said they did not use condoms routinely with him. There was no significant association between vaginal douching practices and using condoms with regular sex partners or clients in the previous week.

Women who had heard of HIV were three times more likely to douche (OR = 3.14, 95% CI 1.80–5.47) compared to those with no knowledge of HIV as shown in Table 2. Subjects who said they were aware of STIs were 2.62-fold more likely to douche (95% CI 1.66–4.12). In contrast to FSWs with a HIV knowledge score of <12, FSWs with a score ≥ 12 were significantly more likely to report douching (OR = 1.58, 95% CI 1.04–2.41). FSWs who perceived themselves as being vulnerable to HIV (OR = 1.87; 95% CI 1.22–2.86) and STIs (OR = 1.76; 95% CI 1.20–2.60) were significantly more likely to douche.

Table 2.

Behavioural characteristics and HIV/STI knowledge of FSWs by vaginal douching practice.

Characteristics		Douchers N (%)	Non-douchers N (%)	OR (95% CI)	P value
Drug use (ever)	Non-drug user	585 (83.0)	120 (17.0)	1.0
	Non-injected illegal drug user	50 (89.3)	6 (10.7)	1.53 (0.74–3.15)	0.23
	Injected drug user	67 (88.2)	9 (11.8)	1.71 (0.72–4.08)	0.25
Duration of commercial sex work (years)	<1 year	260 (81.8)	58 (18.2)	1.0
	1–2 years	256 (85.1)	45 (14.9)	1.27 (0.83–1.94)	0.27
	3–4 years	91 (87.5)	13 (12.5)	1.56 (0.82–2.98)	0.18
	≥5 years	95 (83.3)	19 (16.7)	1.12 (0.63–1.97)	0.71
Number of clients previous week	<7	560 (83.0)	115 (17.0)	1.0
Number of clients previous week	≥7	142 (87.7)	20 (12.3)	1.46 (0.88–2.43)	0.15
Always used condom with every client in previous week	Yes	554 (85.1)	97 (14.9)	1.0
Always used condom with every client in previous week	No	148 (79.6)	38 (20.4)	0.68 (0.45–1.03)	0.07
Always used condom with regular partner in previous week	Yes	56 (84.9)	10 (15.1)	1.0
Always used condom with regular partner in previous week	No	296 (85.6)	50 (14.4)	1.06 (0.51–2.21)	0.88
Age of sexual debut (years)	<18	280 (82.1)	61 (17.9)	1.0
Age of sexual debut (years)	≥18	422 (85.1)	74 (14.9)	1.24 (0.86–1.80)	0.25
Age engaging in commercial sex work	<20	275 (84.1)	52 (15.9)	1.0
Age engaging in commercial sex work	≥20	427 (83.7)	83 (16.3)	0.97 (0.67–1.42)	0.89
Ever heard of STIs	No	80 (70.2)	34 (29.8)	1.0
Ever heard of STIs	Yes	622 (86.0)	101 (14.0)	2.62 (1.66–4.12)	<.01
Ever heard of HIV	No	41 (65.1)	22 (34.9)	1.0
Ever heard of HIV	Yes	661 (85.4)	113 (14.6)	3.14 (1.80–5.47)	<.01
HIV knowledge score	<12	458 (81.9)	101 (18.1)	1.0
HIV knowledge score	≥12	244 (87.8)	34 (12.2)	1.58 (1.04–2.41)	0.03
Perceived vulnerable to STIs	No	373 (80.6)	90 (19.4)	1.0
Perceived vulnerable to STIs	Yes	329 (88.0)	45 (12.0)	1.76 (1.20–2.60)	<.01
Perceived vulnerable to HIV	No	444 (81.2)	103 (18.8)	1.0
Perceived vulnerable to HIV	Yes	258 (89.0)	32 (11.0)	1.87 (1.22–2.86)	<.01

FSWs: Female sex workers; HIV: human immunodeficiency virus; STIs: sexually transmitted infections.

Clinical symptoms and association with douching

Clinical symptoms experienced by the FSWs may have an effect on the vaginal douching. There was a higher prevalence of vaginal douching among FSWs who reported lower abdominal pain, unusual vaginal discharge, and painful intercourse in the previous 12 months before participating in the survey.

HIV/STIs prevalence and association with vaginal douching

The prevalences of STIs were very high in this population, as listed in Table 3. HIV prevalence was 10%. HSV-2 (68%) was the most frequent STI detected among FSWs in this study, followed by C. trachomatis (28%), T. vaginalis (12%), N. gonorrhoeae (11%), and syphilis (8%). In all, 670 (80%) FSWs were infected with one or more of these five tested STIs. Interestingly, FSWs who douched had a higher prevalence of HIV and HSV-2, but they had lower prevalence of N. gonorrheae and C. trachomatis infection. HIV prevalence was significantly higher among FSWs who douched with any product, but when we compared HIV prevalence by type of product used, only toothpaste and medical disinfectant were associated with significant increases in HIV risk.

Table 3.

Association between vaginal douching and HIV/STIs among FSWs.

	Non-douchers (N = 134)	Douched with any product (N = 699)	Ever douched with toothpaste (N = 195)	Ever douched with water only (N = 407)	Ever douching with medical disinfectant (N = 628)
	No (%)	No (%)	No (%)	No (%)	No (%)
HIV	7 (5.2)	77 (11.0)^a	27 (13.9)^a	41 (10.1)	68 (10.8)^a
N. gonorrhoeae	22 (16.4)	74 (10.6)	19 (9.7)	37 (9.1)^a	65 (10.4)^a
C. trachomatis	47 (35.1)	188 (26.9)^a	48 (24.6)^a	99 (24.3)^a	164 (26.1)^a
Syphilis	15 (11.2)	53 (7.6)	16 (8.2)	27 (6.6)	48 (7.6)
T. vaginalis	18 (13.4)	81 (11.6)	23 (11.8)	50 (12.3)	70 (11.2)
HSV-2 seropositive	75 (56.0)	495 (70.8)^a	152 (78.0)^a	274 (67.3)^a	453 (72.1)^a

FSWs: Female sex workers; HIV: human immunodeficiency virus; STIs: sexually transmitted infections.

p < 0.05.

Table 4 displays the results from multivariate logistic regression models evaluating the risk of vaginal douching on HIV/STIs infection. After adjusting for age, ethnicity, education, marital status, and the number of clients in the previous week that were significantly correlated with vaginal douching in univariate analysis, FSWs who douched consistently had a higher prevalence of HIV (adjusted OR [AOR] = 2.29; 95% CI 1.01–5.23) and HSV-2 (AOR = 2.18; 95% CI 1.46–3.24).

Table 4.

Multivariate analysis of association between vaginal douching and HIV/STIs among FSWs.

	Adjusted OR (95% CI)^a	p Value
HIV	2.29 (1.01–5.23)	0.04
N. gonorrhoeae	0.62 (0.37–1.06)	0.08
C. trachomatis	0.68 (0.45–1.01)	0.06
Syphilis	0.73 (0.39–1.37)	0.33
T. vaginalis	0.90 (0.51–1.58)	0.72
HSV-2 seropositive	2.18 (1.46–3.24)	<.01

FSWs: Female sex workers.

Adjusted for age, ethnicity, education, marital status and the number of clients in previous week that were significantly correlated with vaginal douching.

Discussion

The current study indicates that vaginal douching is a common practice among FSWs in China. The 84% douching prevalence in this study is higher than the 64% post-client douching prevalence reported in a study of FSWs in Guangxi province.¹⁹ Interestingly, we found that FSWs who douched had a higher prevalence of HIV and HSV-2, but they had lower prevalence of N. gonorrhoeae and C. trachomatis infection. Our study confirmed that HIV/STI rates were high among FSWs in Yunnan Province, China. The prevalence of any STI in FSWs (80%) in our study was similar to another study of FSWs in Yunnan examining the same STIs (84%).²⁰ In our study, C. trachomatis was the most common bacterial STI followed by T. vaginalis then N. gonorrhoeae, showing similar trends amongst FSWs in Yunnan (58.6%, 43.2%, and 37.8%, respectively) and Guangzhou (32%, 12.5%, and 8%).^20,21

We describe a significant association between douching (with toothpaste or disinfectant) and an increased prevalence of HIV infection. As has been seen in previous studies on this subject, there appears to be a complex relation between HIV infection and vaginal douching. In a study in the Central African Republic, Gresenguet et al.¹⁴ found a positive association between HIV and the use of vaginal agents for the self-treatment of discharge and itching. Dallabetta et al.²² found an increased prevalence of HIV infection among women using non-commercial medicines in Malawi. Two prospective studies were conducted to explore the relationship between douching and incidence of HIV in African women but had contradictory results.^23,24 McClelland et al.²⁴ found a statistically significant association between douching and incident HIV in younger women, but Myer et al.²³ found no association in an older population. The potential mechanisms whereby vaginal douching could possibly enhance HIV transmission are twofold: (1) through irritation of the vaginal mucosa, thus promoting the proliferation of lymphocytes which are target cells for HIV and (2) through dehydration of the vaginal mucosa, rendering the vaginal epithelium more vulnerable to local trauma.²⁵

Women douching with any products were at increased risk for HSV-2 seropositivity compared with women who never douched. Other findings support independent associations between HSV-2 infection and recent douching. Cherpes et al.²⁶ found women practicing vaginal douching to have a higher HSV-2 prevalence. A population-based study in Mexico demonstrates the strong association between HSV-2 seropositivity and current vaginal douching (OR = 1.7; 95% CI, 1.2–2.6).²⁷ Douching might increase the risk for HSV-2 acquisition, either by altering the normal vaginal flora or destroying the protective mucin layer thereby facilitating exposure to the underlying epithelium to virus. Conversely, it is possible that symptoms associated with genital herpes infection increase the likelihood that a woman will douche. However, our data regarding symptoms associated with HSV-2 infection did not support the later speculation.

One important finding in the current study is that women who ever douched were less likely to be infected with C. trachomatis and N. gonorrhoeae, which is inconsistent with another study conducted by Scholes et al.²⁸ They found that women who reported douching 12 months prior to their clinic visit were twice as likely to have cervical chlamydial infection and that, as the frequency of douching increased, the likelihood of chlamydial infection also increased.²⁸ Peters found that douching at least monthly was significantly associated with chlamydia in adolescents.²⁹ Stergachis et al.³⁰ found that douching within the last year was independently predictive of chlamydial infection. However, cross-sectional studies cannot determine reliably whether the douching preceded the disease or if the symptoms led to the douching. This could be down to the women douching before participating in the survey, which would clean and remove cervical discharge containing indicators of infection, especially when chemical agents are used for douching. Therefore, it should be suggested not to carry out vaginal douching before gynecological examination during STI screening.

The current study did not find a significant association between consistent condom use with clients or regular partners and douching practices, which is inconsistent with a study among FSWs in Guangxi.¹⁹ They found that women who douched after having sex with their clients were less likely to report consistent use of condoms. But Fonck found that there was a positive association between condom use and douching among FSWs.³¹ The relation between douching and condom use is a greatly under-researched area.

Detailed knowledge about HIV/STIs was lacking among these subjects, including HIV transmission mode. Most FSWs did not believe that they were susceptible to these diseases, though they have high-risk behaviours and had heard of HIV/STIs. Similarly, among FSWs in Hong Kong, 75% did not perceive themselves as having a higher risk of HIV, and thus only 31% had been previously tested for HIV.³² There is therefore a gap between knowledge, distribution of knowledge, and perceived risk. One important finding in the current study is that women with higher HIV-related knowledge were more likely to report vaginal douching, possibly because they consider douching as a means of HIV/STI prevention, and 78% of FSWs who douched reported preventing disease was an important reason for doing so. Considering the potential increase in risk of HIV/STIs posed by vaginal douching, it is necessary to correct misconceptions about douching and discourage women from douching through educational and prevention activities. In a randomised clinical trial, douching risk reduction counselling succeeded in reducing douching practices.³³

Despite the high rate of STIs in this population, only 31% reported lower abdominal pain, although 44% reported unusual vaginal discharge in the previous 12 months. Data in the current study suggest that FSWs with lower abdominal pain, unusual vaginal discharge, and painful intercourse were more likely to report douching than FSWs without these symptoms. One possible reason was that douching women might expose themselves to a higher risk of STIs. Another possibility was that those women with clinical symptoms might start douching as a means to treat current disease or alleviate vaginal symptoms.

Medical disinfectant was the most common genital cleansing agents used among these FSWs. Not all douching products would be expected to carry comparable risks. Gresenguet et al.¹⁴ found that vaginal douching with non-commercial preparations was associated with an increased risk of HIV, whereas douching with commercial antiseptic preparations was associated with a lower prevalence of this virus. Joesoef et al.³⁴ found that the association with STIs was enhanced if the women douched before sex; AOR were 2.7 (95% CI 1.0–7.3) for douching with water and soap and 5.2 (95% CI 1.6–16.7) for douching with betel leaf or a commercial agent. It is possible that different douching products may have different effects on the vaginal flora or protective mucin layer. Juliano et al.³⁵ tested seven commercial vaginal antiseptic douche solutions against vaginal lactobacilli and found marked in vitro antibacterial activity, often after very short exposure times. Onderdonk et al. found that healthy women who douched with a 4% acetic acid solution experienced a transient reduction of total bacteria that they attributed to the physical washing of the vagina alone.³⁶ However, when they used povidone-iodine, a bactericidal agent, it caused a significant reduction in total bacterial counts that suggested an antiseptic effect in addition to the washing effect. They concluded that, in some individuals, douching may decrease the vaginal bacteria that were present, allowing a rapid proliferation of potential pathogens and increasing the risk of associated infections. Thus, some douche preparations may cause substantial changes in vaginal flora.

There are potential limitations in our study. First, this was a cross-sectional study which could not determine whether douching is a causal factor for STIs or whether STI-related symptoms lead to the douching behaviour. Although there was a higher prevalence of vaginal douching among FSWs who reported lower abdominal pain, unusual vaginal discharge, and painful intercourse, there was no significant association between HIV/HSV-2 infection and those symptoms (data not shown). Therefore, it can be speculated that douching is a causal factor for HIV/HSV-2 infection. Second, because this study was not primarily designed to study douching, some detailed information such as the frequency of douching and when it was performed (before or after having sex with clients or regular partners) were not collected in our study. Third, some information based on self-report, such as use of condoms and vaginal douching, may have been misclassified. To minimise this effect, we asked questions about recent events, such as condom use in the previous week.

In summary, vaginal douching seems to be a common practice among FSWs in China, and we found a significant association between douching and HIV and other STIs. Douching was linked to significantly lower risks of C. trachomatis and N. gonorrhoeae infections and significantly higher risks of HSV-2 and HIV infections. Further prospective studies are required to better understand the complex relation between douching and HIV/STI infection. Given these results (common practice of vaginal douching and misconceptions on douching effectiveness), clinical counselling should be conducted by medical professional and public health workers to avoid douching among FSWs. FSWs must be educated about the health risks associated with vaginal douching.

Footnotes

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

This study was funded by a grant from the National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health (U19 AI51915-05).

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