A prospective cohort study comparing efficacy of 1 dose of quadrivalent human papillomavirus vaccine to 2 and 3 doses at an average follow up of 12 years postvaccination.

Background: While recommending a human papillomavirus (HPV) single-dose vaccination schedule in 2022, the World Health Organization highlighted the need for long-term follow-up studies to monitor waning of protection. We report on vaccine efficacy against HPV infections in 1-, 2-, and 3-dose schedules and protection against cervical precancers at a median follow-up of 12 years postvaccination.

Methods: This randomized multicenter study in India was originally designed to vaccinate unmarried girls aged 10-18 years with either 2 or 3 doses of quadrivalent HPV vaccine.

Impact of age at vaccination and cervical HPV infection status on binding and neutralizing antibody titers at 10 years after receiving single or higher doses of quadrivalent HPV vaccine.

Long-term follow-up of a cohort of unmarried girls who received one, two, or three doses of quadrivalent HPV vaccine, between 10 and 18 years of age, in an Indian multi-centric study allowed us to compare antibody responses between the younger and older age cohorts at 10-years post-vaccination, and study the impact of initiation of sexual activity and cervical HPV infections on antibody levels. Among the younger (10-14 years) recipients of a single dose, 97.7% and 98.

Assessment of Registry-Based Surveillance Statistics Used for Cancer Control in the Dindigul District in South India.

Background: Cancer incidence rates from the Dindigul district were lower by 50% than Chennai in Tamil Nadu for most cancers. This study describes the cancer surveillance statistics and provides an assessment of missing cases from routine registration in the Dindigul Ambilikkai Cancer Registry (DACR), covering a predominantly rural population in the Dindigul district.

Method: A total of 21,214 incident cancers in the DACR during 2003-2017 were examined for this study.

Evaluation of immune response to single dose of quadrivalent HPV vaccine at 10-year post-vaccination.

Background: The recent World Health Organization recommendation supporting single-dose of HPV vaccine will significantly reduce programmatic cost, mitigate the supply shortage, and simplify logistics, thus allowing more low- and middle-income countries to introduce the vaccine. From a programmatic perspective the durability of protection offered by a single-dose will be a key consideration. The primary objectives of the present study were to determine whether recipients of a single-dose of quadrivalent HPV vaccine had sustained immune response against targeted HPV types (HPV 6,11,16,18) at 10 years post-vaccination and whether this response was superior to the natural antibody titres observed in unvaccinated women.

Impact of HPV vaccination on HPV-related oral infections.

Background: Human papillomavirus (HPV) is one of the most common sexually transmitted infections worldwide. Although the efficacy of the HPV vaccine in preventing the development of cervical pre-malignant lesions has been well demonstrated, the efficacy of the HPV vaccine in preventing HPV infection in the upper respiratory tract has been poorly studied.

Methods: In the context of the IARC cohort study of two versus three doses of HPV vaccine in India, we compared the HPV type prevalence in the oral cavity of women vaccinated with three doses, two doses, or a single dose of quadrivalent HPV vaccine with that of unvaccinated women.

Vaccine efficacy against persistent human papillomavirus (HPV) 16/18 infection at 10 years after one, two, and three doses of quadrivalent HPV vaccine in girls in India: a multicentre, prospective, cohort study.

Background: A randomised trial designed to compare three and two doses of quadrivalent human papillomavirus (HPV) vaccine in adolescent girls in India was converted to a cohort study after suspension of HPV vaccination in trials by the Indian Government. In this Article, the revised aim of the cohort study was to compare vaccine efficacy of single dose to that of three and two doses in protecting against persistent HPV 16 and 18 infection at 10 years post vaccination.

Methods: In the randomised trial, unmarried girls aged 10-18 years were recruited from nine centres across India and randomly assigned to either two doses or three doses of the quadrivalent HPV vaccine (Gardasil [Merck Sharp & Dohme, Whitehouse Station, NJ, USA]; 0·5 mL administered intramuscularly).

Two-dose recommendation for Human Papillomavirus vaccine can be extended up to 18 years - updated evidence from Indian follow-up cohort study.

Earlier publication from the ongoing multi-centric study of the International Agency for Research on Cancer to evaluate less than three doses of the quadrivalent Human Papillomavirus (HPV) vaccine in India amongst unmarried girls demonstrated non-inferior total antibody titres, neutralizing antibody titres and antibody avidity in 2-dose recipients compared to 3-dose recipients at 15-18 years of age (Bhatla et al., 2018) [7]. The number of participants recruited at 15-18 years of age was 1515 and 1795 in the 3-dose and the 2-dose groups respectively.

Are two doses of human papillomavirus vaccine sufficient for girls aged 15-18 years? Results from a cohort study in India.

Extending two-dose recommendations of HPV vaccine to girls between 15 and 18 years will reduce program cost and improve compliance. Immunogenicity and vaccine targeted HPV infection outcomes were compared between 1795 girls aged 15-18 years receiving two (1-180 days) and 1515 girls of same age receiving three (1-60-180 days) doses. Immunogenicity outcomes in 15-18 year old two-dose recipients were also compared with the 10-14 year old three-dose (N = 2833) and two-dose (N = 3184) recipients.

Can a single dose of human papillomavirus (HPV) vaccine prevent cervical cancer? Early findings from an Indian study.

Background: Human papillomavirus (HPV) vaccination is a major strategy for preventing cervical and other ano-genital cancers. Worldwide HPV vaccination introduction and coverage will be facilitated if a single dose of vaccine is as effective as two or three doses or demonstrates significant protective effect compared to 'no vaccination'.

Methods: In a multi-centre cluster randomized trial of two vs three doses of quadrivalent HPV vaccination (Gardasil™) in India, suspension of the vaccination due to events unrelated to the study led to per protocol and partial vaccination of unmarried 10-18 year old girls leading to four study groups, two by design and two by default.

Immunogenicity and HPV infection after one, two, and three doses of quadrivalent HPV vaccine in girls in India: a multicentre prospective cohort study.

Background: An increase in worldwide HPV vaccination could be facilitated if fewer than three doses of vaccine are as effective as three doses. We originally aimed to compare the immunogenicity and frequency of persistent infection and cervical precancerous lesions caused by vaccine-targeted HPV after vaccination with two doses of quadrivalent vaccine on days 1 and 180 or later, with three doses on days 1, 60, and 180 or later, in a cluster-randomised trial. Suspension of the recruitment and vaccination due to events unrelated to our study meant that some enrolled girls could not be vaccinated and some vaccinated girls received fewer than the planned number of vaccinations by default.

Effect of Screening on Variation in Cervical Cancer Survival by Socioeconomic Determinants--a Study from Rural South India.

Background: Socioeconomic factors are associated with screening in terms of reducing the risk of cervical cancer. This study aimed to clearly establish the effect of screening on variation in socio-economic factor-specific survival estimates.

Materials And Methods: Survival estimates were calculated using the life table method for 165 women from the routine care control arm and 67 from the visual inspection with acetic acid screening arm diagnosed with cervical cancer during 2000-2006 in rural south India.

Risk of invasive cancer among women visually screened and colposcopy triaged by trained nurses in rural South India.

Objective: To estimate the long-term risk of cervical cancer among women screened by visual inspection with acetic acid (VIA) and to evaluate the benefit of additional colposcopy triage in rural south India.

Methods: A retrospective analysis was conducted among 31 343 women who had undergone VIA at Dindigul district, India between January 1, 2000, and August 5, 2003, as part of a randomized screening trial. Women with positive VIA test results were offered colposcopy triage by trained nurses.

Response to article titled "US-funded measurements of cervical cancer death rates in India: scientific and ethical concerns" by Eric J Suba.

Dr Eric Suba has been distorting facts and persistently disseminating biased and misleading views and statements regarding our studies over the past several years. His article in the Indian Journal of Medical Ethics fails to mention the facts that seem unfavourable to his arguments, and the ethical concerns are unsubstantiated by the evidence. In this context, we present the following clarifications for the attention of your readers, notably with regard to: (i) the study design and inclusion of a control group; (ii) the informed consent of the women participating in the study; (iii) the conformity with international ethical standards and guidelines, and (iv) the provision of screening to women in the control arm of the studies.

Effect of screening on the risk estimates of socio demographic factors on cervical cancer - a large cohort study from rural India.

Background: Prospective cohort studies to determine cofactors with oncogenic HPV- infections for cervical cancer are very rare from developing countries and such data are limited to the few screening trials. Large screening trials provide such data as a by product. Some of the cases are prevented by screening and do not surface as invasive cancers at all.

Socio demographic and reproductive risk factors for cervical cancer - a large prospective cohort study from rural India.

Background: India shows some of the highest rates of cervical cancer worldwide, and more than 70% of the population is living in rural villages. Prospective cohort studies to determine the risk factors for cervical cancer are very rare from low and medium resource countries. The aim of this study was to quantify the effect of risk factors related to cervical cancer in a rural setting in South India.

Visual inspection methods for cervical cancer prevention.

The need for simple, cost-effective screening approaches for cervical cancer prevention in low-resource countries has led to the evaluation of visual screening with 3-5% acetic acid. The low reproducibility and wide variation in accuracy reflect the subjective nature of the test. Pooled sensitivity, specificity, positive and negative predictive values were 80%, 92%, 10% and 99%, respectively, for detecting cervical intraepithelial neoplasia grade 2 or worse lesions.

Cancer pattern and survival in a rural district in South India.

Background: Cancer pattern data are rare and survival data are none from rural districts of India.

Methods: The Dindigul Ambilikkai Cancer Registry (DACR) covering rural population of 2 millions in Dindigul district, Tamil Nadu state, South India, registered 4516 incident cancers during 2003-2006 by active case finding from 102 data sources for studying incidence pattern, of which, 1045 incident cancers registered in 2003 were followed up for estimating survival. House visits were undertaken annually for each registered case for data completion.

Education and cancer incidence in a rural population in south India.

Background: Population-based studies describing the association between education and cancer incidence has not yet been reported from India.

Methods: Information on the educational attainment of 4417 cancer cases aged 14 years and above, diagnosed during 2003-2006 in Dindigul district, Tamil Nadu, India, was obtained from the Dindigul Ambilikkai Cancer Registry, which registers invasive cancer cases by active methods from 102 data sources. Population distribution by 5-year age groups and for four educational levels namely no education, education 12 years, was obtained from census data.

Human papillomavirus infection and cervical cancer prevention in India, Bangladesh, Sri Lanka and Nepal.

Although one-third of the world cervical cancer burden is endured in India, Bangladesh, Nepal and Sri Lanka, there are important gaps in our knowledge of the distribution and determinants of the disease in addition to inadequate investments in screening, diagnosis and treatment in these countries. Prevalence of human papillomavirus (HPV) infection among the general populations varies from 7-14% and the age-specific prevalence across age groups is constant with no clear peak in young women. This observation may be the result of a low clearance rate of incident infections, frequent re-infection/reactivation, limited or no data in target high-risk age groups (teenagers), and sexual behavioural patterns in the population.

Cervical cancer: screening and therapeutic perspectives.

Cervical cancer is a major cause of mortality and premature death among women in their most productive years in low- and medium-resourced countries in Asia, Africa and Latin America, despite the fact that it is an eminently preventable cancer. While cytology screening programmes have resulted in a substantial reduction of cervical cancer mortality in developed countries, they have been shown to have a wide range of sensitivity in most routine settings including in developing countries. Although liquid-based cytology improves sample adequacy, claims on improved sensitivity remain controversial.

Effect of visual screening on cervical cancer incidence and mortality in Tamil Nadu, India: a cluster-randomised trial.

Background: Cervical cancer is the most common cancer among women in developing countries. We assessed the effect of screening using visual inspection with 4% acetic acid (VIA) on cervical cancer incidence and mortality in a cluster randomised controlled trial in India.

Methods: Of the 114 study clusters in Dindigul district, India, 57 were randomised to one round of VIA by trained nurses, and 57 to a control group.

Effectiveness, safety and acceptability of 'see and treat' with cryotherapy by nurses in a cervical screening study in India.

We evaluated a 'see and treat' procedure involving screening, colposcopy, biopsy and cryotherapy by trained nurses in one-visit in field clinics in a cervical screening study in South India for its acceptability, safety and effectiveness in curing cervical intraepithelial neoplasia (CIN). Women positive on visual inspection with acetic acid (VIA) were advised colposcopy, directed biopsies and cryotherapy if they had colposcopic impression of CIN in one visit by nurses in field clinics supervised by a doctor. Side effects and complications were assessed and cure rates were evaluated with VIA, colposcopy and biopsy if colposcopic abnormalities were suspected.