Genital infections in high-risk human papillomavirus positive Paraguayan women aged 30-64 with and without cervical lesions.

OBJECTIVE: To determine the prevalence of genital infections (GIs), including sexual transmitted STIs: Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis, and opportunistic pathogens that generally do not cause STIs, non-classic STI: Ureaplasma urealyticum, Ureaplasma parvum and Mycoplasma hominis, in women with high-risk oncogenic human papillomavirus (hr-HPV) infection and their association with cervical lesions. METHODS: A cross-sectional study was carried out including 231 hr-HPV positive women. Of these, 46 has histologically confirmed cervical intraepithelial neoplasia 3 (CIN3) or more (including CIN3 and cervical cancer lesions-CIN3+). GIs were detected by multiplex real time PCR. Odds ratios (OR) were estimated to explore possible associations between GIs and the presence or absence of CIN3+ lesions. Additionally, we examined associations between sociodemographic, sexual, and clinical characteristics and the presence of GIs. RESULTS: In total, there were 174/231 cases of GIs corresponding to an overall prevalence of 75.3% (95%CI: 69.4-80.4), being non-classic STIs the most common (72.3%) compared to STIs (12.6%). The most prevalent non-classic STI and STI were U. parvum (49.8%) and C. trachomatis (7.4%), respectively. The odds of presenting GIs were 3 times higher in women under 46 years compared to older counterparts (OR: 3.32, 95%CI: 1.74-6.16), and in women with a normal Pap smear with inflammation compared to those without inflammation (OR: 3.31, 95%CI: 1.15-9.77). GIs were equally present in women with and without CIN3+ lesions. CONCLUSION: We observed an association of GIs with inflammation in the Pap smear, but no association with CIN3+, as some of them are very common and likely part of the normal vaginal flora, suggesting that such infections do not appear to be cofactors in cervical carcinogenesis, although larger prospective studies are needed.

Health inequalities in a middle-income country: a systematic review of the Costa Rican case.

Objective: This study systematically reviews evidence of socioeconomic health disparities in Costa Rica, a middle-income country, to elucidate the relationship between socioeconomic status and health outcomes. Methods: Published studies were identified through a systematic review of PubMed (English) and Scielo (Spanish) databases from December 2023 to January 2024, following PRISMA guidelines. Search terms included socioeconomic status, social determinants, social gradient in health, and health inequalities. Results: Of 236 identified references, 55 met the inclusion criteria. Findings were categorized into health inequalities in mortality (among the general population, infants, and older adults), life expectancy, cause-specific mortality, and health determinants or risk factors mediating the association between the social environment and health. The studies indicate higher mortality among the most disadvantaged groups, including deaths from respiratory diseases, violence, and infections. Higher socioeconomic status was associated with lower mortality rates in the 1990s, indicating a positive social gradient in health (RII = 1.3, CI [1.1-1.5]). Disparities were less pronounced among older adults. Urban areas exhibited concentrated wealth and increased risky behaviors, while rural areas, despite greater socioeconomic deprivation, showed a lower prevalence of risky behaviors. Regarding smoking, people living in rural areas smoked significantly less than those in urban areas (7% vs. 10%). Despite the relatively equitable distribution of public primary healthcare, disparities persisted in the timely diagnosis and treatment of chronic diseases. Cancer survival rates post-diagnosis were positively correlated with the wealth of districts (1.23 [1.12-1.35] for all cancers combined). Conclusion: The study highlights the existence of social health inequalities in Costa Rica. However, despite being one of the most unequal OECD countries, Costa Rica shows relatively modest social gradients in health compared to other middle and high-income nations. This phenomenon can be attributed to distinctive social patterns in health behaviors and the equalizing influence of the universal healthcare system.

A surveillance study of cancer incidence and mortality among young adults in Costa Rica.

Background: There has been an increase in certain cancers among young adults (YA) aged 20-39, particularly in Latin America. This is the first study to examine cancer incidence and mortality in YA in Costa Rica, focusing on sex-specific patterns. Methods: Invasive cancer cases (excluding non-melanoma skin cancer) in YA from 2006 to 2015 were obtained from the Costa Rican National Registry of Tumors. Utilising SEER∗Stat software, age-standardized incidence rates (IRs) and incidence rate ratios (IRRs) were calculated. Trends and annual percent changes (APCs) in IRs were estimated using the Joinpoint regression analysis program. Cancer deaths from 2000 to 2021 were obtained from the Costa Rican National Institute of Statistics and Census. Age-standardised mortality rates were calculated using STATA®17. Findings: YA comprised 10.7% of all invasive cancer cases diagnosed from 2006 to 2015. The age-standardized incidence rate (ASIR) of invasive cancer in YA was 50.9/100,000 person-years. The ASIR was twofold higher for females compared to males (IRR = 2.03, 95% CI:1.94, 2.13). This difference increased with age, peaking in the 35-39-year age group (IRR = 2.84, 95% CI:2.62, 3.10). Thyroid, breast, and cervical cancer were the most common in females. Testicular cancer was the most common in males. Leading causes of cancer-related deaths included cervical and breast cancer in females and stomach and brain/nervous system cancer in males. Interpretation: The study highlights sex-specific patterns in cancer incidence and mortality among YA in Costa Rica to increase understanding and improve cancer outcomes in this age group. Funding: This study was funded by the Intramural Research Program of the National Cancer Institute.

SARS-CoV-2 infection prior to vaccination amplifies Fc-mediated humoral profiles in an age-dependent manner.

Immunity acquired by vaccination following infection, termed hybrid immunity, has been shown to confer enhanced protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by enhancing the breadth and potency of immune responses. Here, we assess Fc-mediated humoral profiles in hybrid immunity and their association with age and vaccine type. Participants are divided into three groups: infection only, vaccination only, and vaccination following infection (i.e., hybrid immunity). Using systems serology, we profile humoral immune responses against spikes and subdomains of SARS-CoV-2 variants. We find that hybrid immunity is characterized by superior Fc receptor binding and natural killer (NK) cell-, neutrophil-, and complement-activating antibodies, which is higher than what can be expected from the sum of the vaccination and infection. These differences between hybrid immunity and vaccine-induced immunity are more pronounced in aged adults, especially for immunoglobulin (Ig)G1, IgG2, and Fcγ receptor-binding antibodies. Our findings suggest that vaccination strategies that aim to mimic hybrid immunity should consider age as an important modifier.

Differential long-term bivalent HPV vaccine cross-protection by variants in the Costa Rica HPV vaccine trial.

The AS04-adjuvanted human papillomavirus (HPV)16/18 vaccine, an L1-based vaccine, provides strong vaccine efficacy (VE) against vaccine-targeted type infections, and partial cross-protection to phylogenetically-related types, which may be affected by variant-level heterogeneity. We compared VE against incident HPV31, 33, 35, and 45 detections between lineages and SNPs in the L1 region among 2846 HPV-vaccinated and 5465 HPV-unvaccinated women through 11-years of follow-up in the Costa Rica HPV Vaccine Trial. VE was lower against HPV31-lineage-B (VE=60.7%;95%CI = 23.4%,82.8%) compared to HPV31-lineage-A (VE=94.3%;95%CI = 83.7%,100.0%) (VE-ratio = 0.64;95%CI = 0.25,0.90). Differential VE was observed at several lineage-associated HPV31-L1-SNPs, including a nonsynonymous substitution at position 6372 on the FG-loop, an important neutralization domain. For HPV35, the only SNP-level difference was at position 5939 on the DE-loop, with significant VE against nucleotide-G (VE=65.0%;95%CI = 28.0,87.8) but not for more the common nucleotide-A (VE=7.4%;95%CI = -34.1,36.7). Because of the known heterogeneity in precancer/cancer risk across cross-protected HPV genotype variants by race and region, our results of differential variant-level AS04-adjuvanted HPV16/18 vaccine efficacy has global health implications.

COVID-19 and long-term impact on symptoms and Health-Related Quality of Life in Costa Rica: the RESPIRA cohort study.

BACKGROUND: Evidence continues to accumulate regarding the potential long-term health consequences of COVID-19 in the population. To distinguish between COVID-19-related symptoms and health limitations from those caused by other conditions, it is essential to compare cases with community controls using prospective data ensuring case-control status. The RESPIRA study addresses this need by investigating the lasting impact of COVID-19 on Health-related Quality of Life (HRQoL) and symptomatology in a population-based cohort in Costa Rica, thereby providing a robust framework for controlling HRQoL and symptoms. METHODS: The study comprised 641 PCR-confirmed, unvaccinated cases of COVID-19 and 947 matched population-based controls. Infection was confirmed using antibody tests on enrollment serum samples and symptoms were monitored monthly for 6 months post-enrolment. Administered at the 6-month visit (occurring between 6- and 2-months post-diagnosis for cases and 6 months after enrollment for controls), HRQoL and Self-Perceived Health Change were assessed using the SF-36, while brain fog, using three items from the Mental Health Inventory (MHI). Regression models were utilized to analyze SF-36, MHI scores, and Self-Perceived Health Change, adjusted for case/control status, severity (mild case, moderate case, hospitalized) and additional independent variables. Sensitivity analyses confirmed the robustness of the findings. RESULTS: Cases showed significantly higher prevalences of joint pain, chest tightness, and skin manifestations, that stabilized at higher frequencies from the fourth month post-diagnosis onwards (2.0%, 1.2%, and 0.8% respectively) compared to controls (0.9%, 0.4%, 0.2% respectively). Cases also exhibited significantly lower HRQoL than controls across all dimensions in the fully adjusted model, with a 12.4 percentage-point difference [95%CI: 9.4-14.6], in self-reported health compared to one year prior. Cases reported 8.0% [95%CI: 4.2, 11.5] more physical limitations, 7.3% [95%CI: 3.5, 10.5] increased lack of vitality, and 6.0% [95%CI: 2.4, 9.0] more brain fog compared to controls with similar characteristics. Undiagnosed cases detected with antibody tests among controls had HRQoL comparable to antibody negative controls. Differences were more pronounced in individuals with moderate or severe disease and among women. CONCLUSIONS: PCR-confirmed unvaccinated cases experienced prolonged HRQoL reductions 6 months to 2 years after diagnosis, this was particularly the case in severe cases and among women. Mildly symptomatic cases showed no significant long-term sequelae.

Social gradient and rural-urban disparities in cancer mortality in Costa Rica.

INTRODUCTION: Data on social inequalities in cancer mortality are sparse, especially in low- and middle-income countries. We aimed to analyze the socioeconomic inequalities in cancer mortality in Costa Rica between 2010 and 2018. METHODS: We linked 9-years of data from the National Electoral Rolls, National Birth Index and National Death Index to classify deaths due to cancer and socioeconomic characteristics of the district of residence, as measured by levels of urbanicity and wealth. We analyzed the fifteen most frequent cancer sites in Costa Rica among the 2.7 million inhabitants aged 20 years and older. We used a parametric survival model based on a Gompertz distribution. RESULTS: Compared to urban areas, mixed and rural area residents had lower mortality from pancreas, lung, breast, prostate, kidney, and bladder cancers, and higher mortality from stomach cancer. Mortality from stomach, lung and cervical cancer was higher, and mortality from colorectal cancer, non-Hodgkin lymphoma and leukemia was lower in the most disadvantaged districts, compared to the wealthiest ones. CONCLUSION: We observed marked disparities in cancer mortality in Costa Rica in particular from infection- and lifestyle- related cancers. There are important opportunities to reduce disparities in cancer mortality by targeting cancer prevention, early detection and opportune treatment, mainly in urban and disadvantaged districts.

Field experience with the 8-HPV-type oncoprotein test for cervical cancer screening among HPV-positive women living with and without HIV in LMICs.

Overexpression of HPV-oncoproteins E6 and E7 is necessary for HPV-driven cervical carcinogenesis. Hence, these oncoproteins are promising disease-specific biomarkers. We assessed the technical and operational characteristics of the 8-HPV-type OncoE6/E7 Cervical Test in different laboratories using cervical samples from HPV-positive women living with (WLWH) and without HIV. The 8-HPV-type OncoE6/E7 Test (for short: "OncoE6/E7 test") was performed in 2833 HIV-negative women and 241 WLWH attending multicentric studies in Latin America (ESTAMPA study), and in Africa (CESTA study). Oncoprotein positivity were evaluated at each testing site, according to HIV status as well as type-specific agreement with HPV-DNA results. A feedback questionnaire was given to the operators performing the oncoprotein test to evaluate their impression and acceptability regarding the test. The OncoE6/E7 test revealed a high positivity rate heterogeneity across all testing sites (I2: 95.8%, p < .01) with significant lower positivity in WLWH compared to HIV-negative women (12% vs 25%, p < .01). A similar HPV-type distribution was found between HPV DNA genotyping and oncoprotein testing except for HPV31 and 33 (moderate agreement, k = 0.57). Twenty-one laboratory technicians were trained on oncoprotein testing. Despite operators' concerns about the time-consuming procedure and perceived need for moderate laboratory experience, they reported the OncoE6/E7 test as easy to perform and user-friendly for deployment in resource-limited settings. The high positivity rate variability found across studies and subjectivity in test outcome interpretation could potentially results in oncoprotein false positive/negative, and thus the need for further refinements before implementation of the oncoprotein testing in screen-triage-and-treat approaches is warranted.

Global evaluation of lineage-specific human papillomavirus capsid antigenicity using antibodies elicited by natural infection.

Human Papillomavirus (HPV) type variants have been classified into lineages and sublineages based upon their whole genome sequence. Here we have examined the specificity of antibodies generated following natural infection with lineage variants of oncogenic types (HPV16, 18, 31, 33, 45, 52 and 58) by testing serum samples assembled from existing archives from women residing in Africa, The Americas, Asia or Europe against representative lineage-specific pseudoviruses for each genotype. We have subjected the resulting neutralizing antibody data to antigenic clustering methods and created relational antigenic profiles for each genotype to inform the delineation of lineage-specific serotypes. For most genotypes, there was evidence of differential recognition of lineage-specific antigens and in some cases of a sufficient magnitude to suggest that some lineages should be considered antigenically distinct within their respective genotypes. These data provide compelling evidence for a degree of lineage specificity within the humoral immune response following natural infection with oncogenic HPV.

Randomised clinical trial: efficacy and safety of H. pylori eradication treatment with and without Saccharomyces boulardii supplementation.

BACKGROUND: Standard triple therapy is commonly prescribed Helicobacter pylori eradication regimen in Europe. However, the world is witnessing declines in eradication success. It is crucial to find better treatment options. AIMS: To evaluate efficacy, compliance and side effects of H. pylori eradication treatment by adding Saccharomyces boulardii . METHODS: We conducted a randomized clinical trial within the GISTAR cohort, consisting of healthy individuals aged 40-64 years. Participants were administered clarithromycin-containing triple therapy (clarithromycin 500 mg, amoxicillin 1000 mg, esomeprazole 40 mg) twice daily. Randomization was applied based on two factors: 1)addition of Saccharomyces boulardii CNCM I-745 500 mg BID or not; 2)treatment duration of 10 or 14 days. Treatment completion and adverse events were assessed via telephone interview 21-28 days after medication delivery. The efficacy was evaluated using a 13C-urea breath test (UBT) six months after treatment. RESULTS: Altogether 404 participants were enrolled; data on adverse events were available from 391. Overall, 286 participants received follow-up UBT. Intention-to-treat analysis revealed higher eradication rates for 10-day probiotic treatment (70.8% vs. 54.6%, P  = 0.022), but not for 14-day. Probiotic subgroups combined showed non-significantly higher efficacy in per-protocol analysis (90.6% vs. 85.0%, P  = 0.183). S. boulardii reduced the frequency of adverse events ( P  = 0.033) in 14-day regimen, particularly treatment-associated diarrhea ( P  = 0.032). However, after the adjustment to control Type I error, results lost their significance. CONCLUSION: Addition of S. boulardii to 14-day clarithromycin-containing triple regimen non-significantly lowers the likelihood of diarrhea and does not increase the eradication rate.

Cohort profile: evaluation of immune response and household transmission of SARS-CoV-2 in Costa Rica: the RESPIRA study.

PURPOSE: The RESPIRA cohort aims to describe the nature, magnitude, time course and efficacy of the immune response to SARS-CoV-2 infection and vaccination, population prevalence, and household transmission of COVID-19. PARTICIPANTS: From November 2020, we selected age-stratified random samples of COVID-19 cases from Costa Rica confirmed by PCR. For each case, two population-based controls, matched on age, sex and census tract were recruited, supplemented with hospitalised cases and household contacts. Participants were interviewed and blood and saliva collected for antibodies and PCR tests. Participants will be followed for 2 years to assess antibody response and infection incidence. FINDINGS TO DATE: Recruitment included 3860 individuals: 1150 COVID-19 cases, 1999 population controls and 719 household contacts from 304 index cases. The age and regional distribution of cases was as planned, including four age strata, 30% rural and 70% urban. The control cohort had similar sex, age and regional distribution as the cases according to the study design. Among the 1999 controls recruited, 6.8% reported at enrolment having had COVID-19 and an additional 12.5% had antibodies against SARS-CoV-2. Compliance with visits and specimens has been close to 70% during the first 18 months of follow-up. During the study, national vaccination was implemented and nearly 90% of our cohort participants were vaccinated during follow-up. FUTURE PLANS: RESPIRA will enable multiple analyses, including population prevalence of infection, clinical, behavioural, immunological and genetic risk factors for SARS-CoV-2 acquisition and severity, and determinants of household transmission. We are conducting retrospective and prospective assessment of antibody levels, their determinants and their protective efficacy after infection and vaccination, the impact of long-COVID and a series of ancillary studies. Follow-up continues with bimonthly saliva collection for PCR testing and biannual blood collection for immune response analyses. Follow-up will be completed in early 2024. TRIAL REGISTRATION NUMBER: NCT04537338.

Prevalencia y determinantes de la infección por virus de papiloma humano en mujeres jóvenes de Guanacaste y Puntarenas, Costa Rica, 2004-2005.

OBJETIVO: Estimar la prevalencia e identificar determinantes de la infección por el virus del papiloma humano (VPH) en mujeres jóvenes (18-25 años). Material y métodos. Se analizaron datos de 5 871 mujeres sexualmente activas a quienes se les realizó una entrevista y toma de muestras cervicouterinas para detección de VPH y citología durante la visita de reclutamiento del Ensayo de Vacunación contra VPH16/18 en Costa Rica. Se calculó la prevalencia total para cualquier tipo de VPH y tipos oncogénicos, no oncogénicos y específicos, con intervalos de confianza al 95% (IC95%). Se utilizó regresión logística múltiple paso-a-paso para identificar determinantes asociados con la infección. RESULTADOS: La prevalencia total de VPH fue 50.0% (IC95% 48.8,51.3) y por tipos oncogénicos fue 33.8% (IC95% 32.6,35.0). El VPH-16 fue el tipo más prevalente (8.3%, IC95% 7.6,9.0). Los determinantes asociados con un alto riesgo de infección prevalente por VPH oncogénicos fueron no estar casada/unión libre, >1 compañero sexual, infección concomitante por Chlamydia trachomatis, y entre aquéllas con un único compañero sexual en su vida, un compañero con antecedente de múltiples compañeras sexuales. Conclusión. Se confirma la asociación de las infecciones por VPH oncogénicos con el comportamiento sexual de la mujer y se destacan los comportamientos del compañero sexual.

Reproducible and clinically translatable deep neural networks for cervical screening.

Cervical cancer is a leading cause of cancer mortality, with approximately 90% of the 250,000 deaths per year occurring in low- and middle-income countries (LMIC). Secondary prevention with cervical screening involves detecting and treating precursor lesions; however, scaling screening efforts in LMIC has been hampered by infrastructure and cost constraints. Recent work has supported the development of an artificial intelligence (AI) pipeline on digital images of the cervix to achieve an accurate and reliable diagnosis of treatable precancerous lesions. In particular, WHO guidelines emphasize visual triage of women testing positive for human papillomavirus (HPV) as the primary screen, and AI could assist in this triage task. In this work, we implemented a comprehensive deep-learning model selection and optimization study on a large, collated, multi-geography, multi-institution, and multi-device dataset of 9462 women (17,013 images). We evaluated relative portability, repeatability, and classification performance. The top performing model, when combined with HPV type, achieved an area under the Receiver Operating Characteristics (ROC) curve (AUC) of 0.89 within our study population of interest, and a limited total extreme misclassification rate of 3.4%, on held-aside test sets. Our model also produced reliable and consistent predictions, achieving a strong quadratic weighted kappa (QWK) of 0.86 and a minimal %2-class disagreement (% 2-Cl. D.) of 0.69%, between image pairs across women. Our work is among the first efforts at designing a robust, repeatable, accurate and clinically translatable deep-learning model for cervical screening.

Cervical Cancer Screening and Treatment algorithms using Human Papillomavirus testing - lessons learnt from a South African pilot randomized controlled trial.

BACKGROUND: To report quantitative and qualitative results on cervical cancer (CC) HPV-based screening and treatment algorithms, with/out triage with visual inspection after acetic acid (VIA), followed by ablative treatment (AT). METHODS: Women 30-54 years-old from Durban, South Africa were recruited, regardless of HIV status, randomized into one of two study arms and screened for HPV. VIA-triage arm: HPV-positive women were triaged using VIA, biopsied and received AT if VIA-positive and eligible; no-triage arm: eligible HPV-positive women received AT. Women ineligible for AT were referred to colposcopy. Women were asked about side effects immediately and one week after AT. Retention to screening and treatment algorithms was compared between arms. RESULTS: 350 women (275 HIV-uninfected and 75 women living with HIV, (WLWH)) were allocated to receive HPV testing with VIA-triage (n=175) or no-triage (n=175). HPV prevalence was 28% (95%CI=23-33); WLWH: 52% (95%CI=40-64) vs HIV-uninfected: 21% (95%CI=17-27) (p<0.05). Among women who underwent VIA triage with histological diagnosis, 3/17 were VIA negative with CIN2+; 14/18 were VIA positive with

Estimating the cumulative incidence of SARS-CoV-2 infection in Costa Rica: modelling seroprevalence data in a population-based cohort.

Background: The true incidence of SARS-CoV-2 infection in Costa Rica was likely much higher than officially reported, because infection is often associated with mild symptoms and testing was limited by official guidelines and socio-economic factors. Methods: Using serology to define natural infection, we developed a statistical model to estimate the true cumulative incidence of SARS-CoV-2 in Costa Rica early in the pandemic. We estimated seroprevalence from 2223 blood samples collected from November 2020 to October 2021 from 1976 population-based controls from the RESPIRA study. Samples were tested for antibodies against SARS-CoV-2 nucleocapsid and the receptor-binding-domain of the spike proteins. Using a generalized linear model, we estimated the ratio of true infections to officially reported cases. Applying these ratios to officially reported totals by age, sex, and geographic area, we estimated the true number of infections in the study area, where 70% of Costa Ricans reside. We adjusted the seroprevalence estimates for antibody decay over time, estimated from 1562 blood samples from 996 PCR-confirmed COVID-19 cases. Findings: The estimated total proportion infected (ETPI) was 4.0 times higher than the officially reported total proportion infected (OTPI). By December 16th, 2021, the ETPI was 47% [42-52] while the OTPI was 12%. In children and adolescents, the ETPI was 11.0 times higher than the OTPI. Interpretation: Our findings suggest that nearly half the population had been infected by the end of 2021. By the end of 2022, it is likely that a large majority of the population had been infected. Funding: This work was sponsored and funded by the National Institute of Allergy and Infectious Diseases through the National Cancer Institute, the Science, Innovation, Technology and Telecommunications Ministry of Costa Rica, and Costa Rican Biomedical Research Agency-Fundacion INCIENSA (grant N/A).

Latin America and the Caribbean Code Against Cancer 1st Edition: 17 cancer prevention recommendations to the public and to policy-makers (World Code Against Cancer Framework).

Preventable risk factors are responsible of at least 40% of cases and almost 45% of all cancer deaths worldwide. Cancer is already the leading cause of death in almost half of the Latin American and the Caribbean countries constituting a public health problem. Cost-effective measures to reduce exposures through primary prevention and screening of certain types of cancers are critical in the fight against cancer but need to be tailored to the local needs and scenarios. The Latin America and the Caribbean (LAC) Code Against Cancer, 1st edition, consists of 17 evidence-based recommendations for the general public, based on the most recent solid evidence on lifestyle, environmental, occupational, and infectious risk factors, and medical interventions. Each recommendation is accompanied by recommendations for policymakers to guide governments establishing the infrastructure needed to enable the public adopting the recommendations. The LAC Code Against Cancer has been developed in a collaborative effort by a large number of experts from the region, under the umbrella strategy and authoritative methodology of the World Code Against Cancer Framework. The Code is a structured instrument ideal for cancer prevention and control that aims to raise awareness and educate the public, while building capacity and competencies to policymakers, health professionals, stakeholders, to contribute to reduce the burden of cancer in LAC.

Latin American and the Caribbean Code Against Cancer 1st edition: Infections and cancer.

About 13% of all cancers around the world are associated with infectious agents, particularly in low-resource settings. The main infectious agents associated with cancer are Helicobacter pylori (H. pylori), that causes gastric cancer, human papillomavirus (HPV) that causes cervical, vulvar, vaginal, penile, anal, and oropharyngeal cancer, hepatitis B and C viruses that cause liver cancer, and human immunodeficiency virus (HIV), associated with cancers of the cervix, Kaposi sarcoma (KS) and non-Hodgkin´s lymphoma. In Latin America and the Caribbean (LAC), about 150,000 cancer cases are caused annually by infections. The LAC Cancer Code Against Cancer consists of a set of 17 evidence-based and individual-level cancer prevention recommendations targeted to the general population, suited to the epidemiological, socioeconomic, and cultural conditions of the region, and tailored to the availability and accessibility of health-care systems. The recommendations with respect to infection-driven malignancies include testing and treating for H. pylori in the context of specific public health programs, vaccination against HPV and Hepatitis B Virus (HBV) and detection and treatment of chronic infections with HBV, Hepatitis C virus (HCV) and HIV, in addition to the promotion of safe sex and use of condoms to prevent sexually transmitted infections (STI). Countries, policy makers, health care systems and individuals should consider the adoption of these recommendations to help reduce the incidence and mortality of infection-related cancers in LAC, to improve quality of life of individuals and reduce the costs of cancer care in the region.

Performance of cervical cytology and HPV testing for primary cervical cancer screening in Latin America: an analysis within the ESTAMPA study.

Background: Cervical cytology remains widely used as the initial tool in cervical cancer screening worldwide. WHO guidelines recommend replacing cytology with primary HPV testing to reach cervical cancer elimination goals. We assessed the performance of cytology and high-risk HPV testing to detect cervical precancer, cervical intraepithelial neoplasia (CIN) grade 3 or worse (CIN3+) among women aged 30-64 years participating in the ESTAMPA study. Methods: Women were screened with cytology and HPV across ESTAMPA study centres in Latin America. Screen-positives were referred to colposcopy with biopsy collection and treatment as needed. Those with no evident precancer were recalled at 18-months for a second HPV test to complete disease ascertainment. Performance indicators for cytology and HPV to detect CIN3+ were estimated. Findings: 30,606 participants with available cytology and HPV results were included in the analysis. A total of 440 histologically confirmed CIN3s and 30 cancers were diagnosed. Cytology sensitivity for CIN3+ was 48.5% (95% CI: 44.0-53.0), whereas HPV testing had a sensitivity of 98.1% (95% CI: 96.3-96.7). Specificity was 96.5% (95% CI: 96.3-96.7) using cytology and 88.7% (95% CI: 88.3-89.0) with HPV. Performance estimates varied substantially by study centre for cytology (ranging from 32.1% to 87.5% for sensitivity and from 89.2% to 99.5% for specificity) while for HPV results were more consistent across sites (96.7%-100% and 83.6-90.8%, respectively). Interpretation: The limited and highly variable sensitivity of cytology strongly supports transition to the more robust and reproducible HPV-based cervical screening to ensure progress towards global cervical cancer elimination targets in Latin America. Funding: IARC/WHO, UNDP, HRP/WHO, NCI and local funders.

Behavioral factors and SARS-CoV-2 transmission heterogeneity within a household cohort in Costa Rica.

INTRODUCTION: Variability in household secondary attack rates and transmission risks factors of SARS-CoV-2 remain poorly understood. METHODS: We conducted a household transmission study of SARS-CoV-2 in Costa Rica, with SARS-CoV-2 index cases selected from a larger prospective cohort study and their household contacts were enrolled. A total of 719 household contacts of 304 household index cases were enrolled from November 21, 2020, through July 31, 2021. Blood specimens were collected from contacts within 30-60 days of index case diagnosis; and serum was tested for presence of spike and nucleocapsid SARS-CoV-2 IgG antibodies. Evidence of SARS-CoV-2 prior infections among household contacts was defined based on the presence of both spike and nucleocapsid antibodies. We fitted a chain binomial model to the serologic data, to account for exogenous community infection risk and potential multi-generational transmissions within the household. RESULTS: Overall seroprevalence was 53% (95% confidence interval (CI) 48-58%) among household contacts. The estimated household secondary attack rate is 34% (95% CI 5-75%). Mask wearing by the index case is associated with the household transmission risk reduction by 67% (adjusted odds ratio = 0.33 with 95% CI: 0.09-0.75) and not sharing bedroom with the index case is associated with the risk reduction of household transmission by 78% (adjusted odds ratio = 0.22 with 95% CI 0.10-0.41). The estimated distribution of household secondary attack rates is highly heterogeneous across index cases, with 30% of index cases being the source for 80% of secondary cases. CONCLUSIONS: Modeling analysis suggests that behavioral factors are important drivers of the observed SARS-CoV-2 transmission heterogeneity within the household.

When living in the same house with known SARS-CoV-2 cases, household members may change their behavior and adopt preventive measures to reduce the spread of SARS-CoV-2. To understand how behavioral factors affect SARS-CoV-2 spreading in household settings, we focused on household members of individuals with laboratory-confirmed SARS-CoV-2 infections and followed the way SARS-CoV-2 spread within the household, by looking at who had antibodies against the virus, which means they were infected. We also asked participants detailed questions about their behavior and applied mathematical modeling to evaluate its impact on SARS-CoV-2 transmission. We found that mask-wearing by the SARS-CoV-2 cases, and avoiding sharing a bedroom with the infected individuals, reduces SARS-CoV-2 transmission. However, caring for SARS-CoV-2 cases, and prolonged interaction with infected individuals facilitate SARS-CoV-2 spreading. Our study helps inform what behaviors can help reduce SARS-CoV-2 transmission within a household.

Estimating human papillomavirus vaccine efficacy from a single-arm trial: proof-of-principle in the Costa Rica Vaccine Trial.

BACKGROUND: The World Health Organization recommends a 1- or 2-dose human papillomavirus (HPV) vaccination schedule for females aged 9 to 20 years. Studies confirming the efficacy of a single dose and vaccine modifications are needed, but randomized controlled trials are costly and face logistical and ethical challenges. We propose a resource-efficient single-arm trial design that uses untargeted and unaffected HPV types as controls. METHODS: We estimated HPV vaccine efficacy (VE) from a single arm by comparing 2 ratios: the ratio of the rate of persistent incident infection with vaccine-targeted HPV 16 and 18 (HPV 16/18) and cross-protected types HPV 31, 33, and 45 (HPV 31/33/45) to vaccine-unaffected types HPV 35, 39, 51, 52, 56, 58, 59, and 66 (HPV 35/39/51/52/56/58/59/66) vs the ratio of prevalence of these types at the time of trial enrollment. We compare VE estimates using only data from the bivalent HPV 16/18 vaccine arm of the Costa Rica Vaccine Trial with published VE estimates that used both the vaccine and control arms. RESULTS: Our single-arm approach among 3727 women yielded VE estimates against persistent HPV 16/18 infections similar to published 2-arm estimates from the trial (according-to-protocol cohort: 91.0% , 95% CI = 82.9% to 95.3% [single-arm] vs 90.9% , 95% CI = 82.0% to 95.9% [2-arm]; intention-to-treat cohort: 41.7%, 95% CI = 32.4% to 49.8% [single-arm] vs 49.0% , 95% CI = 38.1% to 58.1% [2-arm]). VE estimates were also similar in analytic subgroups (number of doses received; baseline HPV serology status). CONCLUSIONS: We demonstrate that a single-arm design yields valid VE estimates with similar precision to a randomized controlled trial. Single-arm studies can reduce the sample size and costs of future HPV vaccine trials while avoiding concerns related to unvaccinated control groups. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00128661.