Sexual practices and HPV infection in unvaccinated young adults.

The present study aimed to evaluate the association of genital and oral HPV infection among different sexual practices in both sexes. In total, 6388 unvaccinated men and women aged 16-25 years from all state capitals of Brazil were enrolled in through primary care services between September 2016 and November 2017. Genital and oral HPV genotyping was performed using the Roche Linear Array. Poisson regression analysis with robust variance was conducted to examine factors associated with overall HPV infection. A higher prevalence of genital HPV was found in women who practiced oral sex (57.85%) and in men who practiced all types of sex (65.87%). However, having more sexual partners and being younger were more important than the type of sex practiced. HPV 6 (7.1%) and 16 (10.5%) were significantly more prevalent in women who practiced oral sex, while HPV 6 (23.96%) and 11 (21.49%) were more prevalent in men who practiced anal sex. The type of sex was not associated with oral HPV prevalence. Genital and oral HPV infection were not associated by different sexual practices in the studied population.

Conscious and pre-conscious attentional bias to food images in patients subjected to Roux-en-Y gastric bypass.

Attentional bias (AB) to food after bariatric surgery might be a cognitive marker for weight regain. The visual probe task (VPT) is commonly used to capture AB at automatic, pre-conscious, and conscious orientation of attention. The aim of this study was to investigate how the preoperative BMI of patients submitted to Roux-en-Y gastric bypass (RYGB) impacts AB to food. We assessed patients who had preoperative BMI>50 (n = 28) or preoperative BMI<50 (n = 31) months after the RYGB procedure. Participants underwent clinical, psychological, and VPT evaluations. In VPT, pairs of food and matching non-food images were shown for 100 ms, 500 ms or 2000 ms and AB for food was assessed for each exposure time. A significant AB to food was observed at 2000 ms for all patients in this study, suggesting that the overall sample were consciously orienting their attention toward food cues after surgery, a finding that might be relevant for understanding weight control. When groups with preoperative BMI higher and lower than 50 kg/m2 were compared, a significant difference on AB to food stimuli at 500 ms was observed, controlling for excess weight lost since surgery and postoperative time. Subjects with preoperative BMI>50 had a positive and reliable AB to food while subjects with preoperative BMI<50 had a negative AB. This suggests that food stimuli have a higher incentive salience even after surgery for those with BMI>50, which might explain why subjects with higher preoperative weight have higher risks for weight regain. These results may indicate that RYGB can impact incentive salience for food cues in a differential manner, increasing conscious AB in all patients and decreasing pre-conscious AB only in those with BMI<50 kg/m2.

A Nationwide Evaluation of the Prevalence of Human Papillomavirus in Brazil (POP-Brazil Study): Protocol for Data Quality Assurance and Control.

BACKGROUND: The credibility of a study and its internal and external validity depend crucially on the quality of the data produced. An in-depth knowledge of quality control processes is essential as large and integrative epidemiological studies are increasingly prioritized. OBJECTIVE: This study aimed to describe the stages of quality control in the POP-Brazil study and to present an analysis of the quality indicators. METHODS: Quality assurance and control were initiated with the planning of this nationwide, multicentric study and continued through the development of the project. All quality control protocol strategies, such as training, protocol implementation, audits, and inspection, were discussed one by one. We highlight the importance of conducting a pilot study that provides the researcher the opportunity to refine or modify the research methodology and validating the results through double data entry, test-retest, and analysis of nonresponse rates. RESULTS: This cross-sectional, nationwide, multicentric study recruited 8628 sexually active young adults (16-25 years old) in 119 public health units between September 2016 and November 2017. The Human Research Ethics Committee of the Moinhos de Vento Hospital approved this project. CONCLUSIONS: Quality control processes are a continuum, not restricted to a single event, and are fundamental to the success of data integrity and the minimization of bias in epidemiological studies. The quality control steps described can be used as a guide to implement evidence-based, valid, reliable, and useful procedures in most observational studies to ensure data integrity. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/31365.

Behavioral factors associated with multiple-type HPV genital infections: data from a cross-sectional study in young women in Brazil.

OBJECTIVES: To investigate the pattern of multiple human papillomavirus (HPV) infections and associated factors in young women who access the Brazilian public health care system to better understand the characteristics of multiple HPV infections, a critical issue in this era of multivalent vaccines. METHODS: This was a cross-sectional, multicenter study with sexually active unvaccinated women (16-25 years old) from 119 primary Brazilian healthcare centers between September 2016 and November 2017. Cervical samples were collected by trained health professionals, and HPV detection was performed in a central laboratory by Linear Array. RESULTS: Of the 5268 women, 33.00% (95% CI 31.07-34.92) had multiple infections. At least one type of high-risk HPV was present in 85.50% of all multiple infections. All HPV types were detected more frequently in association with other types than alone. Young individuals who were single or in a casual relationship and those who had more than one sexual partner in the past year were more likely to have multiple infections. CONCLUSIONS: In this work, a high rate of multiple HPV infections among unvaccinated young adults tended to increase due to certain risk factors. Such data can provide insight for decision makers in the development of public policies regarding HPV prevention.

Understanding the characteristics of multiple infections is critical in the era of HPV multivalent vaccines for the prevention of cervical carcinomas. Therefore, in this cross-sectional study, we aimed to investigate the pattern of multiple HPV infections and associated factors in 5,268 sexually active unvaccinated women (16­25 years old) who access the Brazilian public health care system. Cervical samples were collected by trained health professionals, and HPV detection was performed in a central laboratory by Linear Array. A total of 33.00% (95% CI 31.07­34.92) had multiple infections (60.43% of the HPV-positive sample). The number of HPV types in a multiple infection ranged from 2 to 14 different types. The viral types more frequently identified were HPV 16 and 52. All HPV types were detected more frequently in association with other types than alone. The incidence of multiple infections was 1.29 times higher in single than in married or cohabitating participants. Women who had two or more partners in the last year also had higher rates of multiple infections than those who had fewer than two sexual partners. In conclusion, a high prevalence of multiple infections prior to the national HPV immunization program was observed, especially with the increase in less safe behavior factors.

Prevalence of oral HPV infection in unvaccinated young adults in Brazil.

OBJECTIVES: This study aimed to report the national prevalence of oral HPV infection among unvaccinated women and men aged 16-25 years who utilized the public primary care services. METHODS: POP-Brazil is a cross-sectional, multicentric, nationwide survey conducted between September 2016 and November 2017. Recruitment was based in 119 public primary care practices in 26 state capitals and the Federal District of Brazil. Trained health professionals conducted face-to-face interviews. Oral samples were collected with mouthwash and gargle cycles. Genotyping was performed using the Roche PCR-based linear array genotyping test. Sampling weights by sex and age were applied. RESULTS: Valid oral HPV samples were collected from 5071 (96.88%) participants; 4005 women and 1066 men. Mean participant age was 21.63 years. Overall HPV prevalence was 1.69% (n = 73, 95% CI 1.05-2.32). Thirty individuals presented at least one high-risk HPV type [0.57% (95% CI, 0.29-0.85)]. There were no associations between age, sex, sociodemographic characteristics, drug use or sexual behavior and oral HPV prevalence. CONCLUSION: The prevalence of oral HPV infection in Brazilian teenagers and young adults is low, with no sociodemographic or behavioral correlates.

Effectiveness of a universal vaccination program with an HPV quadrivalent vaccine in young Brazilian women.

We examined human papillomavirus (HPV) vaccine effectiveness in a nationwide sample of women aged 16 to 25 years who utilized the public health system in Brazil. This was a cross-sectional, multicentric survey conducted between September 2016 and November 2017 (POP-Brazil Study). A total of 5,945 young adult women were recruited from 119 public primary care units from all 27 federative units of Brazil by trained health professionals. The participants participated in a face-to-face interview and provided biological samples for genital HPV analysis. HPV genotyping was performed using a Linear Array HPV genotyping test in a central laboratory. Sampling weights were applied to the data. Overall, 11.92% (95% CI 10.65, 13.20) of the participants reported having been vaccinated. The frequency of vaccination was highest in 16- to 17-year-old women, with a decreasing vaccination rate with increasing age, and vaccinated women were more likely to belong to the high socioeconomic status group. The use of a quadrivalent vaccine decreased the HPV types 6, 11, 16, and 18 by 56.78%, from 15.64% in unvaccinated women to 6.76% in vaccinated women (P < 0.01), even after adjustment for age. Those who received the vaccine had lower HPV 16 (2.34% in vaccinated vs 8.91% in unvaccinated, P < 0.01) and 6 rates (2.06% vs 5.77%, P < 0.01). Additionally, a higher rate of high-risk HPV types other than HPV 16 and 18 (40.47% in vaccinated vs 32.63% in unvaccinated, P < 0.01) was observed. In conclusion, the results of this study support the effectiveness of HPV vaccination in Brazil. Continuous surveillance must be assured to monitor the HPV infection rate in the vaccination era.

Preoperative Binge Eating and Weight Loss After Bariatric Surgery: A Systematic Review and Meta-analysis.

BACKGROUND: Several studies have investigated if bariatric surgery candidates with binge eating disorder (BED) are at risk for suboptimal postoperative weight loss. The aim of this systematic review with meta-analysis was to evaluate the association between binge eating diagnosed preoperatively and weight loss after bariatric surgery. METHODS: MEDLINE, EMBASE, CENTRAL, LILACS, and other specialized databases were searched on August 2020. Clinical trials and observational studies including individuals who had undergone any type of bariatric surgical treatment with preoperative evaluation of BED and at least one postoperative measure of weight were initially selected. Four reviewers independently screened for eligibility. The mean difference was calculated using the random-effects model. RESULTS: Nineteen studies, comprising 3223 participants (80.25% women; median age 41 years), met the inclusion criteria for meta-analysis. At 6 months postoperative, the percentage of total weight loss (%TWL) was not significantly different between BED and non-BED groups [6 studies, 914 participants: - 0.75% (95% CI, - 2.79 to 1.29; I2 = 0%)], even when analyzing only those three studies that included gold standard assessment tools. No significant differences were found at 12, 24, 36, or 60 months. CONCLUSIONS: Pre-bariatric BED seems to have little or no influence on weight loss after surgery. However, many questions remain unanswered because of the use of different measures across studies. The heterogeneity among studies emphasizes the importance of investigators using the same assessment measures.

Sex differences in the prevalence and determinants of HPV-related external genital lesions in young adults: a national cross-sectional survey in Brazil.

BACKGROUND: External genital lesions (EGL) are the most common sexually transmitted infections (STIs). We aimed to evaluate the prevalence, determinants and sex differences in EGL among young adults from Brazil. METHODS: Overall, 7694 participants (aged 16 to 25 years) underwent an interview, genital examination and sampling for HPV genotyping. RESULTS: The prevalence of EGL was 4.08% (234) and is more frequent in men (5.72%) than women (2.31%) (p <  0.001). Genital lesions were significantly associated with male sex, infection by high-risk and multiple HPV types, having more than two sexual partners in the last year, smoking status and the presence of other STI. While alcohol use was associated with a higher prevalence of EGL in women, same-sex sexual relationship increase the prevalence in men. In the EGL group, 67.79% (p = 0.032) were positive for HPV infection and the types HPV6 and HPV11 were the most prevalent ones. CONCLUSION: The prevalence of EGL in young adults was consistently high, and most cases were associated with genital HPV infection and STIs. Although men have a higher prevalence, both sexes share most genital lesion determinants. The promotion of sexual education and vaccination especially focus in young men, who are usually outside the targets of primary health care programmes, can prevent EGL in Brazilian young adults.

Binge eating scores pre-bariatric surgery and subsequent weight loss: A prospective, 5 years follow-up study.

BACKGROUND & AIMS: To compare groups of bariatric patients with preoperative scores of Binge Eating Scale (BES) above and below the clinical cut off value on weight outcomes up to 60 months following surgery. METHODS: This is a prospective observational study involving 108 Brazilian patients (follow-up rate: 48.1%) operated by Roux-en-Y gastric bypass. In the preoperative period, they were clinically evaluated, and BES was applied. Based on the scores, patients were categorized as high or low according to established cut off 17 for binge eaters. Follow-up weight loss was obtained (3, 6, 12, 24, 36, 48, and 60 months) using data from medical records. The percentage of total weight loss (%TWL) was examined by generalized linear model. RESULTS: 41.7% of patients had BES scores higher than 17 at baseline. Weight loss was significant up to 12 months. The greatest weight loss was at 24 months of follow-up, ranging from 2.7 to 110.4 kg (mean 42.9 ± 17.8 kg). In the short postoperative period (3, 24, and 36 months), %TWL was significantly different between groups. At 24 months, patients with higher scores lost more %TWL than those with lower scores (35.1 ± 0.8% vs 31.6 ± 0.7%, p = 0.029). However, this difference was not fount at 60 months postoperatively (mean 28.9 ± 9.6%). In a multivariate analysis, the presence of depression, age, and BES score were not associated with %TWL at 24 and 60 months. CONCLUSIONS: The results suggest that preoperative BES scores point to a similar weight loss after bariatric surgery. Further studies with long-term follow-up are necessary to evaluate this finding.

Prevalence of human papillomavirus (HPV) in Brazil: A systematic review and meta-analysis.

OBJECTIVES: This study aimed to estimate the prevalence of genital, anal and oral HPV infection in Brazil through systematic review and meta-analysis. METHODS: We searched EMBASE, LILACS, MEDLINE, Web of Science and SciELO from inception to December 2018. Original research articles that assessed the prevalence of genital (i.e., cervical, penile), anal and oral HPV infection in Brazil were selected in pairs by independent authors. No sex, age, HPV vaccination, language or date restrictions were applied. HPV prevalence was estimated and stratified according to risk factors population and by geographic area throughout the country. The study prevalence was pooled using a random effects model. Analysis was performed using R (version 3.5.2), packages meta version 4.9-4 and metaphor 2.0-0. This review is registered on PROSPERO under protocol number CRD42016032751. RESULTS: We identified 3,351 references. After the screening process, 139 of them were eligible for this systematic review (57,513 total participants). Prevalence of cervical HPV was 25.41% (95% CI 22.71-28.32). Additionally, prevalence was 36.21% (95% CI 23.40, 51.33) in the penile region, 25.68% (95%CI 14.64, 41.04) in the anal region, and 11.89% (95%CI 6.26, 21.43) in the oral region. Subgroup analysis showed prevalence in each anatomic site was higher in high-risk populations. CONCLUSION: The prevalence of HPV is high in the Brazilian population and varies by population risk and anatomic body site, with lower rates in the oral cavity compared to that in the cervical, penile and anal region. Studies on HPV have primarily been developed to evaluate infection and cancer in the cervical region. There is a profound lack of HPV data in many geographic regions of Brazil and for different anatomic sites.

STOP HPV study protocol: a nationwide case-control study of the association between oropharyngeal cancer and human papillomavirus (HPV) infection in Brazil.

INTRODUCTION: Human papillomavirus (HPV) is the most common sexually transmitted infection and is associated with several types of cancer. The number of cases of HPV-associated head and neck squamous cell carcinomas (HNSCCs), especially oropharyngeal carcinomas, has increased significantly in recent years despite decreased tobacco smoking rates. Currently, no data concerning the risk factors and prevalence of HPV in HNSCC patients in all regions of Brazil are available, making it difficult to promote advances in this field of public health. Therefore, our goal is to determine the impact of infection by HPV, including HPVs with different genotypes, on head and neck cancer and the risk factors associated with the development of head and neck cancer in all regions of Brazil. METHODS AND ANALYSIS: This is a case-control study that will include 622 patients and 622 controls from all regions of Brazil. A questionnaire will be applied to gather information on sociodemographic, behavioural and health factors. Oral, cervical or penile/scrotal, and anal specimens and serum samples will be collected from all participants. Formalin-fixed paraffin-embedded tissue from tumour biopsies will be analysed only in the case group. Molecular and serological analyses will be performed to evaluate the presence and role of HPV in the development of head and neck cancer. ETHICS AND DISSEMINATION: This project was approved by the research ethical committee of the proposing institution (Hospital Moinhos de Vento, number 2.852.060). Ethical approval from the collaborators is currently under evaluation and is not yet complete. The results of this study will be presented at meetings with the Brazilian Ministry of Health through technical reports and to the scientific community at national and international events, with subsequent publication of scientific articles.

Evaluating sexual health in sex workers and men who have sex with men: the SMESH cross-sectional protocol study.

INTRODUCTION: Human papillomavirus (HPV) infection is transmitted through skin-to-skin contact, and vaginal and anal sex are the most common transmission routes. Sex workers and men who have sex with men (MSM) are more exposed to the virus, and therefore, a higher frequency of this infection would be expected. The prevalence of HPV infection types and the forms and factors of transmission must be investigated to control infection-related outcomes. This protocol study will be the first nationwide study with a uniform methodology to evaluate HPV prevalence of and infection types among sex workers and MSM in Brazil. METHODS AND ANALYSIS: This multicentre cross-sectional study will be conducted with a respondent-driven sampling method to recruit 1174 sex workers and 1198 MSM from all regions of Brazil. The study will consist of preliminary interviews to verify the eligibility criteria and characterise the network size as well as a second questionnaire to obtain sociodemographic, behavioural and sexual information. Specimens from the oral cavity and anal and cervical or penile/scrotal sites will be collected. All HPV samples will be processed in a certified central laboratory. Other sexually transmitted infections will be evaluated by interview and by rapid testing for HIV and syphilis. Strict quality control will be conducted using different procedures, including the training and certification of the health professionals responsible for acquiring data and monitoring visits. ETHICS AND DISSEMINATION: The project was approved by the research ethics committee of the main institution and the corresponding ethics committees of the recruitment sites. Due to the literature gap on the sexual health of sex workers and MSM and the intense stigma surrounding these populations, a critical analysis of the study results will contribute to epidemiological knowledge and will be useful for the development of strategies against virus morbidities.

Perception of Primary Health Care professionals as participants in a national survey about HPV in Brazil: an experience report. / Percepção dos profissionais da Atenção Primária à Saúde como participantes de uma pesquisa nacional sobre HPV: um relato de experiência.

OBJECTIVE: to describe the perception of data collection performed by primary health care professionals as collaborators of the national POP-Brasil survey - Epidemiological Study of National Prevalence of HPV Infection. METHODS: in all, 217 professionals from 119 primary care units participated in the POP-Brasil Study conducted in the 26 Brazilian capitals and the Federal District. RESULTS: the professionals were trained and certified locally for collecting data and biological material from 8,580 participants; participation in the study allowed professionals to recognize the importance of their work. CONCLUSION: the successful experience confirms how important it is to do research as part of work practice, as long as professionals are trained and have adequate support, given that their work routine is compatible with the execution of the research protocol.

Self-reported syphilis and associated factors among Brazilian young adults: findings from a nationwide survey

Abstract The aim of this study was to evaluate self-reported syphilis and associated factors in sexually active young adults (16-25 years old) in the Public Health System in Brazil. This was a cross-sectional study with 8071 participants recruited from 119 primary care units. Of these, 224 (2.86%, 95% CI 2.29-3.43%) reported having the disease. Age, lower socio-economic class, being a smoker, not using a condom at first sexual intercourse, and ever had a same-sex sexual experience were associated with syphilis. The results reinforce the importance of implementing strategies focused on socio-economic class and early sexual education that encourage condom use from the beginning of sexual activity.

Self-reported syphilis and associated factors among Brazilian young adults: findings from a nationwide survey.

The aim of this study was to evaluate self-reported syphilis and associated factors in sexually active young adults (16-25 years old) in the Public Health System in Brazil. This was a cross-sectional study with 8071 participants recruited from 119 primary care units. Of these, 224 (2.86%, 95% CI 2.29-3.43%) reported having the disease. Age, lower socio-economic class, being a smoker, not using a condom at first sexual intercourse, and ever had a same-sex sexual experience were associated with syphilis. The results reinforce the importance of implementing strategies focused on socio-economic class and early sexual education that encourage condom use from the beginning of sexual activity.

Factors associated with HPV and other self-reported STI coinfections among sexually active Brazilian young adults: cross-sectional nationwide study.

OBJECTIVES: To analyse factors associated with genital human papillomavirus (HPV) and other self-reported sexually transmitted infection (STI) coinfections among women and men aged 16-25 years from Brazil. DESIGN: A cross-sectional, nationwide, multicentre study. SETTING: 119 primary healthcare centres between September 2016 and November 2017. PARTICIPANTS: 6388 sexually active young adults were enrolled by trained health professionals. PRIMARY OUTCOME MEASURE: Genital HPV and other self-reported STI coinfections. RESULTS: Of 3512 participants with valid data for genital HPV and (STI)-positive status, 276 (9.60%, 95% CI 7.82% to 11.36%) had HPV/STI coinfection. Among men, HPV/STI coinfection was more prevalent than HPV infection alone. Among HPV-positive participants, the percentage of subjects who reported having another STI was highest for gonorrhoea at 4.24% (95% CI 2.67% to 5.81%), followed by syphilis, herpes and HIV. Smoking, drug use and ever having a same-sex sexual experience were risk factors that were uniquely associated with HPV/STI coinfection compared with HPV infection alone. CONCLUSIONS: The results identified a low prevalence of self-reported STIs, but in participants with at least one STI, the prevalence of HPV was high. These results reinforce the importance of implementing strategies to prevent risky behaviours among Brazilian young adults.

Prevalence of Vitamin D Depletion, and Associated Factors, among Patients Undergoing Bariatric Surgery in Southern Brazil.

BACKGROUND: Hypovitaminosis D is common, before and after gastric bypass surgery. The prevalence of hypovitaminosis D in a large group of candidates for bariatric surgery in Brazil and South America has not been studied. OBJECTIVE: To evaluate the prevalence of hypovitaminosis D and associated factors in patients undergoing bariatric surgery in Southern Brazil. MATERIALS AND METHODS: Cross-sectional study involving all patients presenting for bariatric surgery at Hospital de Clínicas de Porto Alegre, from January 2013 to June 2018. Data were extracted from the patients' electronic medical records. Patients who were taking multivitamin supplements or vitamin D supplements, who had renal insufficiency, or had missing data for 25(OH) vitamin D [25(OH)D] levels were excluded. RESULTS: A total of 291 patients were included. Mean subjects' age was 44.9 (SD 10.7) years, and BMI 49.3 (SD 8.3) kg/m2; 76.6% of the study patients were women, and 87.3% were white. More than half the patients (55.3%) were vitamin D deficient (serum 25(OH)D ≤ 19.9 ng/ml), and 37.1% had insufficient levels (20-29.9 ng/mL). Mean vitamin D level was 19.2 ng/mL (SD 7.6). An inverse correlation was found between 25(OH)D levels and BMI. Vitamin D deficiency was more prevalent in patients with higher BMI [PR 1.02; CI 95% (1.00-1.03)], higher fasting glucose [PR 1.01; CI 95% (1.00-1.01)], in nonwhite patients [PR 1.58; CI 95% (1.30-1.92)] and during autumn/winter season [PR 1.41; CI 95% (1.14-1.75)]. CONCLUSIONS: Prevalence of vitamin D insufficiency and deficiency is very high among patients presenting for bariatric surgery in Southern Brazil, and the known associated factors are confirmed in this population.

Hospital quality indicators: a systematic review.

PURPOSE: The purpose of this paper is to identify and describe hospital quality indicators, classifying them according to Donabedian's structure, process and outcome model and in specific domains (quality, safety, infection and mortality) in two care divisions: inpatient and emergency services. DESIGN/METHODOLOGY/APPROACH: A systematic review identified hospital clinical indicators. Two independent investigators evaluated 70 articles/documents located in electronic databases and nine documents from the grey literature, 35 were included in the systematic review. FINDINGS: In total, 248 hospital-based indicators were classified as infection, safety, quality and mortality domains. Only 10.2 percent were identified in more than one article/document and 47 percent showed how they were calculated/obtained. Although there are scientific papers on developing, validating and hospital indicator assessment, most indicators were obtained from technical reports, government publications or health professional associations. RESEARCH LIMITATIONS/IMPLICATIONS: This review identified several hospital structure, process and outcome quality indicators, which are used by different national and international groups in both research and clinical practice. Comparing performance between healthcare organizations was difficult. Common clinical care standard indicators used by different networks, programs and institutions are essential to hospital quality benchmarking. ORIGINALITY/VALUE: To the authors' knowledge, this is the first systematic review to identify and describe hospital quality indicators after a comprehensive search in MEDLINE/PubMed, etc., and the grey literature, aiming to identify as many indicators as possible. Few studies evaluate the indicators, and most are found only in the grey literature, and have been published mostly by government agencies. Documents published in scientific journals usually refer to a specific indicator or to constructing an indicator. However, indicators most commonly found are not supported by reliability or validity studies.

Knowledge about HPV and vaccination among young adult men and women: Results of a national survey.

BACKGROUND: In addition to screening by Pap smears, vaccination against human papillomavirus (HPV) can dramatically reduce cervical cancers caused by the virus. The acceptance of HPV vaccination is directly related to HPV knowledge. This research aimed to evaluate knowledge about HPV and vaccination among men and women aged 16-25 years who use the public health system in Brazil. METHODS: This was a cross-sectional, multicenter study of sexually active young adults recruited from 119 primary care units between 2016 and 2017. All participants answered a face-to-face standardized questionnaire. RESULTS: Of 8581 participants, the mean percentage of correct answers about HPV and vaccination was 51.79% (95% CI 50.90-52.67), but 75.91% (95% CI 74.13-77.69) had awareness of the HPV vaccination. Women answered a higher proportion of questions correctly than men did (p = 0.0003). Lower education level was the variable that most interfered with knowledge. The best information sources for knowledge were both health professionals and the media (1.33%, 95% CI 1.03-1.70). CONCLUSIONS: The results emphasize the importance of educational programs about HPV and vaccination among young adults, especially in socially disadvantaged populations. These findings can help to increase the vaccination rate in the country and to stimulate public health policies.