Oncogenic human papilloma virus and cervical pre-cancerous lesions in brothel-based sex workers in India

Prevalence of human papilloma virus infection and risk of cervical intraepithelial neoplasia among female sex workers in Mumbai, India

Introduction

Cervical cancer, mostly caused by human papilloma virus (HPV), has disproportionately high incidence in developing countries. HPV infection being essentially a sexually transmitted infection, high-risk behaviour women with multiple sexual contacts like female sex workers (FSWs) are at higher risk of co-infection with HPV and of developing cervical precancer and cancer.

Objective

This study aimed to determine the prevalence and determinants of HPV infection and cervical intraepithelial neoplasia (CIN) among FSWs in Mumbai, India.

Methods

A cross-sectional study was conducted among 448 FSWs, between the ages of 18-50 years, by collaborating with local non-government organizations working for the health and welfare of FSW communities at sexually transmitted diseases clinics. All FSWs were screened for HPV DNA by hybrid capture II followed by reference diagnosis of colposcopy and/or cervical biopsy.

Results

The prevalence of HPV DNA positivity was 35.5% and CIN was 2.2%. Factors significantly associated with HPV DNA positivity were age group younger than 30 years odds ratio (OR = 2.098, 95% confidence interval (CI) 1.408-3.127), Illiteracy (OR = 2.015, 95% CI 1.305-3.112), being single (OR = 2.409, 95% CI 1.558-3.724), less than 18 years of age at time of initiating work as FSW (OR = 3.718, 95% CI 3.718-2.392), having more than five clients per day (OR = 2.078, 95% CI 1.301-3.318), been working as a FSW for more than 5 years (OR = 2.321, 95% CI 1.455-3.701), not using barrier contraception methods (OR = 5.155, 95% CI 3.395-7.827) and having no exposure to human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) education program (OR = 29.153, 95% CI 15.385-55.240). FSWs with a positive HPV DNA test are substantially more likely to have CIN compared to those with a negative test (OR = 7.6, 95% CI 1.59-36.25).

Conclusion

The prevalence of HPV infection and CIN was high among FSWs. FSWs with a positive HPV DNA test had a seven times higher risk of developing CIN. The persistence of HPV infection is expected to significantly raise the risk of cervical cancer in the future. It is suggested to have an integrated approach towards cervical cancer screening and HIV/AIDS control activities.

Human papillomavirus genotype distribution and factors associated among female sex workers in West Africa

OBJECTIVES

This study aimed to: (1) Estimate HPV prevalence and genotype distribution among female sex workers (FSWs) in Mali and Benin as well as the prevalence of multiple HPV type infections in this group, and (2) Identify potential risk factors associated with high-risk (HR) HPV infections.

METHODS

We analyzed baseline data of 665 FSWs aged ≥ 18 years recruited during a prospective cohort of cervical cancer screening in Cotonou (Benin) and Bamako (Mali) from 2017 to 2018. The Linear Array HPV genotyping test was used to identify HPV genotypes. Descriptive statistics and multivariate log-binomial regression were used. Adjusted prevalence ratios (APR) with 95% confidence intervals (95%CI) were estimated to identify risk factors associated with HR-HPV infections.

RESULTS

HPV data were available for 659 FSWs (Benin: 309; Mali: 350). The mean age was 35.0 years (± 10.7) in Benin and 26.8 years (± 7.6) in Mali. The overall HPV prevalence rates were 95.5% in Benin and 81.4% in Mali. About 87.7% and 63.4% of FSWs harbored ≥ 2 HPV types in Benin and Mali, respectively. The top three prevalent HR-HPV among FSWs in Benin were: HPV58 (37.5%), HPV16 (36.6%) and HPV52 (28.8%). Corresponding patterns in Mali were HPV16 (15.7%), HPV51 (14.3%) and HPV52 (12.9%). In Benin, the main factors associated with HR-HPV were vaginal douching (APR = 1.17; 95%CI:1.02-1.34) and gonococcal infection (APR = 1.16; 95%CI:1.04-1.28), while in Mali they were sex work duration ≤ 1 year (APR = 1.35; 95%CI:1.10-1.65) and HIV infection (APR = 1.26; 95%CI: 1.06-1.51).

CONCLUSION

Our study found a very high prevalence of HPV infection as well as high frequency of multiple HPV type infections in FSWs in two countries in West Africa. These findings suggest the necessity to emphasize cervical cancer prevention in this high-risk group.

Prevalence and genotype distribution of genital human papillomavirus infection in female sex workers in the world: a systematic review and meta-analysis

BACKGROUND

Female sex workers (FSWs) are amongst the most susceptible groups to acquire human papillomavirus (HPV) infection and consequently, to develop cervical intraepithelial neoplasia and cervical cancer. This is the first systematic review and meta-analysis to provide estimates of the pooled prevalence of HPV infection and the distribution of HPV types among FSWs across the world.

METHODS

Five computerized databases were searched for relevant studies published since the inception date of databases to September 2019. The pooled HPV prevalence was calculated by the random effect model described by DerSimonian-Laird. Subgroup analysis was performed to identify the probable sources of heterogeneity. The meta-analysis was performed using the "Metaprop" function in the R package Meta.

RESULTS

Sixty-two studies involving 21,402 FSWs from 33 countries were included in this meta-analysis, and the pooled HPV prevalence was 42.6% (95% confidence interval (CI): 38.5-46.7%). HPV-16 (10.1, 95% CI: 8.2-12.5%), HPV-52 (7.9, 95% CI: 5.9-10.7%), and HPV-53 (6.0, 95% CI: 4.4-8.1%) were the most common high-risk HPV types identified among FSWs. The pooled estimated prevalence of HPV infection among FSWs before and after 2010 were slightly different, 43.6% (95% CI: 36.1-51.4%) and 41.9% (95% CI: 37.2-46.8%), respectively.

CONCLUSION

Due to the high prevalence of HPV infection, particularly with high-risk types, FSWs have a great susceptibility to the development of cervical and vaginal cancers. Furthermore, they can transmit their infection to their clients, which may result in a high prevalence of HPV and the incidence of HPV-associated malignancies among the general population.

PCR and Genotyping for HPV in Cervical Cancer Patients

Aims:

To devise nested multiplex polymerase chain reaction (NMPCR) protocol for detection of mucosal human papilloma viruses (HPVs) and typing of HPV-16 and -18 in formalin-fixed, paraffin-embedded (FFPE) tissues of carcinoma cervix (CaCx).

Settings and Design:

Cross-sectional observational study.

Materials and Methods:

NMPCR was done for simultaneous detection of HPV, targeting 134 bp L1 capsid gene employing GP+/mGP+ primers and typing of genotypes-16 and -18, targeting E6/E7 gene from 34 FFPE tissue blocks of CaCx and cervical intraepithelial neoplasia (CIN). Detection of 142 bp consensus sequence of L1 capsid gene was performed by nested PCR employing MY/GP+ primers. Sequencing of selected PCR amplicons of the later protocol obtained from control cell line DNA and 5 select samples were done for validation of the NMPCR protocol.

Statistical Analysis Used:

Calculation of percentage from the Microsoft Excel Software.

Results:

Of 26 FFPE samples of CaCx, 17 (65.3%) samples were found positive for HPV by NMPCR. Amplicons of 142 bp L1 capsid gene employing MY/GP+ primers were observed in 11 (42.3%) samples of CaCx. Nearly 25% samples of CIN were positive for HPV. On sequence analysis, it was observed that the sample typed as HPV-16 by NMPCR was found to be the same on sequencing of amplicons obtained after MY/GP+ nested PCR.

Conclusions:

This study indicates the usefulness of our NMPCR protocol for detection of mucosal HPVs and typing of HPV-16 and -18 from FFPE tissue samples of CaCx. The NMPCR protocol may be used to detect HPV and type common genotypes-16 and -18 in fresh tissue of cervical biopsy or scrape samples for screening of CaCx.

Molecular genotyping of human papillomavirus l1 gene in low-risk and high-risk populations in Bangkok

BACKGROUND

Human papillomavirus (HPV) infections in Thailand are a public health concern, but information on HPV infection in sex workers and men who have sex with men (MSM) is limited. The aim of this study was to measure the prevalence and genotype distribution of HPV among low- and high-risk, HIV-negative populations.

METHODS

A total of 300 participants were categorized as general women, female sex workers, MSM, and MSM sex workers. Human papillomavirus infections were identified by the Papanicolaou test and nested polymerase chain reaction. A phylogenetic analysis of partial HPV L1 genes was performed.

RESULTS

Abnormal cytology was found in 5% of general women, 10% of female sex workers, 24% of MSM, and 28% of MSM sex workers. Human papillomavirus was detected in 9% of general women, 13% of female sex workers, and 30% in both MSM and the MSM sex workers. The prevalence of HPV high-risk genotypes was significantly higher in female sex workers and MSM, whereas low-risk genotypes and genital warts were significantly higher in MSM sex workers. Significantly more patients with genital warts and cervical intraepithelial neoplasia I/anal intraepithelial neoplasia I harbored low-risk genotypes, whereas those with cervical intraepithelial neoplasia II/anal intraepithelial neoplasia II harbored high-risk genotypes.

CONCLUSIONS

High- and low-risk HPV genotypes persist in high-risk groups in Bangkok. Some genotypes infecting at-risk populations are not vaccine preventable. These findings may help to elucidate the prevalence of HPV infections in Thailand and serve as the basis for additional investigations into risk factors for these populations.

Epidemiology of cervical cancer with special focus on India

Cervical cancer is on the declining trend in India according to the population-based registries; yet it continues to be a major public health problem for women in India. Multifactorial causation, potential for prevention, and the sheer threat it poses make cervical cancer an important disease for in-depth studies, as has been attempted by this paper. This paper attempts to review the available knowledge regarding the epidemiology and pattern of cervical cancer; types of HPV (human papilloma virus) prevalent among cervical cancer patients and among women in general, high-risk groups such as commercial sex workers, and HIV (human immunodeficiency virus)-positive women; and the role of the national program on cancer in control efforts. The peak age of incidence of cervical cancer is 55-59 years, and a considerable proportion of women report in the late stages of disease. Specific types of oncogenic HPV-16, 18 have been identified in patients with cervical cancer. Other epidemiological risk factors are early age at marriage, multiple sexual partners, multiple pregnancies, poor genital hygiene, malnutrition, use of oral contraceptives, and lack of awareness. A multipronged approach is necessary which can target areas of high prevalence identified by registries with a combination of behavior change communication exercises and routine early screening with VIA. Sensitizing the people of the area, including menfolk, is necessary to increase uptake levels. Vaccination against types 16 and 18 can also be undertaken after taking into confidence all stakeholders, including the parents of adolescent girls. Preventing and treating cervical cancer and reducing the burden are possible by targeting resources to the areas with high prevalence.

Analysis of duration of risk behaviour for key populations: a literature review

Background

The objective of this paper is to review literature in order to calculate regional estimates of the average duration of time individuals maintain a specific high-risk behaviour.

Methods

The review targeted the key populations of female sex workers (FSW), male clients of female sex workers (MCFSW), people who inject drugs (injecting drug users (IDU)) and high-risk men who have sex with men (MSM). To be included in the review the study had to provide information on (1) the time a person spent at risk until death or cessation of the risk behaviour, (2) the percentage of the sample who initiated the risk behaviour in less than a year or (3) the mean or median duration of the behaviour from a representative sample.

Results

49 papers were found for the FSW population describing the period of time FSW stay in sex work to be between 2.9 years (Asia) and 12 years (Latin America). Eight papers were found for MCFSW showing the duration of the risk behaviour in this category varying from 4.6 years in Africa to 32 years in Asia. 86 papers were reviewed for the population of IDU showing that the average time a person injects illegal drugs varies from 5.6 years (Africa) to 21 years (South America). No information was found for duration of high-risk behaviour among MSM; instead, the definitions found in the literature for high- and low-risk behaviour among MSM were described.

Conclusions

There is high variability of estimates of duration of high-risk behaviours at regional level. More research is needed to inform models and prevention programmes on the average duration of time individuals maintain a specific high-risk behaviour.

Prevalence of human papillomavirus and co-existent sexually transmitted infections among female sex workers, men having sex with men and injectable drug abusers from eastern India

BACKGROUND

Human papillomavirus (HPV) is a very common sexually transmitted disease affecting both men and women and is responsible for different ano-genital cancers in either sex. Co-existing sexually transmitted infections (STI) including HIV have been considered as important co-factors for carcinogenesis induced by HPV. The purpose of this study was to determine the prevalence of any HPV, HPV 16 and HPV 18 and also concomitant STIs among female sex workers (FSW), men having sex with men (MSM) and injectable drug users (IDU).

MATERIAL AND METHOD

This cross-sectional study was conducted among 45 FSWs, 26 MSMs and 58 IDUs who attended the STI or de-addiction clinics. Genital scrape samples collected from glans penis and coronal sulcus in males and cervical squamo-columnar junction in females were tested for HPV DNA by PCR using HPV L1 consensus primer. Type specific PCR to detect HPV 16 and 18 was done on the samples positive on consensus PCR. All participants were tested for associated STIs including HIV and hepatitis B and cervical cytology was done on all females.

RESULTS

Among the FSWs, HPV was detected in 73.3% and HPV 16 and 18 was detected in 25.7%. Though the HPV prevalence was similarly high among MSMs (69.2%) and IDUs (72.4%), the prevalence of HPV 16 and 18 was much lower in these groups compared to the FSWs. Prevalence of cervico-vaginal infection with Trichomonas vaginalis and syphilis was significantly higher in the HPV positive women compared to the HPV negative women. There was no statistically significant difference in the prevalence of other STIs among HPV positive and negative women and men.

CONCLUSION

HPV infection is highly prevalent among FSW, MSM and IDUs. Trichomonas vaginalis infection is more frequent in HPV positive women.

Prevalence and genotype distribution of cervical human papillomavirus infection among female sex workers in Asia: a systematic literature review and meta-analysis

Cervical human papillomavirus (HPV) infection is highly transmissible. Although there are many studies on HPV infection in general population of women globally, little attention has been paid to female sex workers (FSWs) in Asia. In this study, we used a meta-analytic approach to systematically analyse the literature to elucidate the prevalence and genotype distribution of cervical HPV infection among FSWs in Asia. Fourteen eligible studies were identified in five databases, and data including 4198 FSWs from nine Asian countries were aggregated. Crude estimates of cervical HPV prevalence among FSWs in this region ranged from 12.8% to 84.8%. FSWs had a nearly 10-fold risk of HPV infection than the general population of women. Stratified analysis showed that HPV prevalence was higher in East Asia than other subregions and in younger FSWs than older FSWs. HPV genotype distribution was statistically different between East Asia and South-east Asia. In East Asia, the most prevalent genotypes were HPV 16 (23.9%), 18 (11.0%), 58 (9.4%), 56 (6.3%) and 52 (5.3%), while they were HPV 52 (12.9%), 16 (8.5%), 58 (5.2%), 18 (5.0%) and 66 (4.9%) in South-east Asia. HPV 31, 33 and 35 were less frequently found in both subregions. HPV infection was substantial among FSWs in some Asian countries. More studies are necessary to illustrate the overall picture of HPV infection in this region.

Oncogenic HPV among HIV infected female population in West Bengal, India

BACKGROUND

Prevalence of both cervical cancer and Human Immunodeficiency Virus (HIV) infection are very high in India. Natural history of Human Papilloma Virus (HPV) infection is known to be altered in HIV positive women and there is an increased possibility of persistence of HPV infections in this population. Therefore, this study was conducted to understand the epidemiology and circulating genotypes of oncogenic HPV among HIV positive and negative female population in West Bengal, India.

METHODS

In this hospital-based cross-sectional study, 93 known HIV positive females attending a pre-ART registration clinic and 1106 HIV negative females attending a Reproductive and Child Health Care Clinic were subjected to study. Cervical cell samples collected from the study population were tested for the presence of HPV 16, 18 using specific primers. Roche PCR assay was used to detect other specific HPV genotypes in the cervical cells specimens of HIV positive cases only.

RESULTS

Prevalence of HPV 16, 18 among HIV positive females (32.2%; n = 30) was higher than HIV negative females (9.1%; n = 101). About 53% (23/43) of cases with oncogenic HPV were infected with genotypes other than 16, 18 either as single/multiple infections. HPV 18 and HPV 16 were the predominant genotypes among HIV positive and HIV negative subjects respectively. Oncogenic HPV was not found to be associated with age and duration of sexual exposure. But the presence of HIV was found to a statistically significant predictor oncogenic HPV.

CONCLUSION

The currently available HPV vaccines offer protection only against HPV 16 and 18 and some cross- protection to few associated genotypes. These vaccines are therefore less likely to offer protection against cervical cancer in HIV positive women a high percentage of who were infected with non-16 and non-18 oncogenic HPV genotypes. Additionally, there is a lack of sufficient evidence of immunogenicity in HIV infected individuals. Therefore, prevention of cervical cancer in HIV positive women must be focused towards early detection of oncogenic HPV & cervical cytological abnormality followed by an appropriate treatment.