Publications by authors named "Carolina Porras"

Background: The Costa Rica HPV Vaccine Trial provided initial evidence that 1 dose of the bivalent human papillomavirus (HPV) vaccine induces stabilizing antibody levels that may provide extended protection against HPV-16/18 infections. We report antibody seropositivity and stability 11 to 16 years after vaccination.

Methods: We invited a random subset of Costa Rica HPV Vaccine Trial participants (n = 398) who had received 3 doses and all women (n = 203) who had received 1 dose at 18 to 25 years of age to follow-up visits 11, 14, and 16 years after vaccination.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF
Article Synopsis
  • Hybrid immunity, which occurs after vaccination following infection, offers stronger protection against SARS-CoV-2 by enhancing immune response effectiveness.
  • The study compares immune profiles of individuals with infection only, vaccination only, and hybrid immunity, finding that hybrid immunity results in better antibody performance and activation of immune cells.
  • Results indicate that older adults particularly benefit from hybrid immunity, highlighting the need for vaccination strategies to consider age differences in immune responses.
View Article and Find Full Text PDF
Article Synopsis
  • The AS04-adjuvanted HPV16/18 vaccine shows strong effectiveness against targeted HPV types and partial protection against related types, with variations in efficacy observed based on viral lineages and genetic differences.
  • In a study involving nearly 8,000 women, the vaccine's effectiveness against HPV31 was significantly lower for lineage-B compared to lineage-A, highlighting the impact of specific genetic variants on vaccine response.
  • Findings reveal important implications for global health, indicating that differential vaccine efficacy against various HPV variants could influence cancer risk across different populations and regions.
View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF
Article Synopsis
  • Researchers classified Human Papillomavirus (HPV) types into lineages and sublineages based on their whole genome sequences.
  • They examined antibodies produced after natural infections with different HPV variants (specifically oncogenic types) using serum samples from women in various global regions.
  • The study found that antibodies showed varying recognition of lineage-specific antigens, suggesting that some HPV lineages may be antigenically distinct, indicating a more complex immune response to these infections than previously understood.
View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

In Costa Rica (CR), only one report on head and neck cancer (HNC) incidence trends (1985-2007) has been published and no investigations on the epidemiology of potentially human papillomavirus (HPV)-related and HPV-unrelated HNCs have been done. We examined the age-standardized incidence rates (IRs) and trends of head and neck squamous cell carcinomas (HNSCC) and compared incidence trends of potentially HPV-related and HPV-unrelated HNSCCs. We obtained all available HNC cases for the period 2006-2015 from the Costa Rican National Cancer Registry of Tumors and the population estimates from the Costa Rican National Institute of Statistics and Census.

View Article and Find Full Text PDF

Many countries with the highest burdens of cervical cancer have not yet offered human papillomavirus (HPV) vaccines to most of their age-eligible girls, who as adults also have limited or no access to effective cervical cancer screening or treatment. There are now 2 complementary developments that could make HPV vaccines more accessible and affordable: 1) the current and projected increases in HPV vaccine supply; and 2) the permissive recommendation for single-dose HPV vaccination schedules. This change in policy paired with the healthier HPV vaccine supply is an incredible opportunity to facilitate rapid access and expansion of HPV vaccination.

View Article and Find Full Text PDF

Variability in household secondary attack rates (SAR) and transmission risks factors of SARS-CoV-2 remain poorly understood. To characterize SARS-CoV-2 transmission in a household setting, we conducted a household serologic 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.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates the effectiveness of administering one dose of HPV vaccine compared to historical studies that showed high efficacy with one dose over an 11-year period against HPV16 and HPV18.
  • Researchers conducted the Dose Reduction Immunobridging and Safety Study (DoRIS) in Tanzania involving girls aged 9-14 years, randomly assigning them to receive one, two, or three doses of either a 2-valent or 9-valent HPV vaccine.
  • The primary goal was to analyze the antibody responses after one dose and determine if these responses were comparable to those found in previous trials, applying statistical methods to assess non-inferiority of immune responses.
View Article and Find Full Text PDF

Background: Breast cancer incidence is increasing rapidly in Latin America, with a higher proportion of cases among young women than in developed countries. Studies have linked inflammation to breast cancer development, but data is limited in premenopausal women, especially in Latin America.

Methods: We investigated the associations between serum biomarkers of chronic inflammation (interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), leptin, adiponectin) and risk of premenopausal breast cancer among 453 cases and 453 matched, population-based controls from Chile, Colombia, Costa Rica, and Mexico.

View Article and Find Full Text PDF

Introduction: Human papillomavirus (HPV) vaccines protect against incident HPV infections, which cause cervical cancer.

Objectives: We estimated the prevalence and incidence of HPV infections in young adult women to understand the impact of an HPV vaccination programme in this population.

Methods: We collected cervical specimens from 6322 unvaccinated women, aged 18-37 years, who participated in the Costa Rica Vaccine Trial and its long-term follow-up.

View Article and Find Full Text PDF

Ultra-processed food intake has been linked to an increased risk of breast cancer in Western populations. No data are available in the Latin American population although the consumption of ultra-processed foods is increasing rapidly in this region. We evaluated the association of ultra-processed food intake to breast cancer risk in a case-control study including 525 cases (women aged 20-45 years) and 525 matched population-based controls from Chile, Colombia, Costa Rica and Mexico.

View Article and Find Full Text PDF

Background: In women vaccinated against human papillomavirus (HPV), reductions in cervical disease and related procedures results in more women having intact transformation zones, potentially increasing the risk of cervical lesions caused by non-vaccine-preventable HPV types, a phenomenon termed clinical unmasking. We aimed to evaluate HPV vaccine efficacy against cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and cervical intraepithelial neoplasia grade 3 or worse (CIN3+) attributed to non-preventable HPV types in the long-term follow-up phase of the Costa Rica HPV Vaccine Trial (CVT).

Methods: CVT was a randomised, double-blind, community-based trial done in Costa Rica.

View Article and Find Full Text PDF

Background: We investigated the impact of human papillomavirus (HPV) vaccination on the performance of cytology-based and HPV-based screening for detection of cervical precancer among women vaccinated as young adults and reaching screening age.

Methods: A total of 4632 women aged 25-36 years from the Costa Rica HPV Vaccine Trial were included (2418 HPV-vaccinated as young adults and 2214 unvaccinated). We assessed the performance of cytology- and HPV-based cervical screening modalities in vaccinated and unvaccinated women to detect high-grade cervical precancers diagnosed over 4 years and the absolute risk of cumulative cervical precancers by screening results at entry.

View Article and Find Full Text PDF

Necessary stages of cervical carcinogenesis include acquisition of a carcinogenic human papillomavirus (HPV) type, persistence associated with the development of precancerous lesions, and invasion. Using prospective data from immunocompetent women in the Guanacaste HPV Natural History Study (NHS), the ASCUS-LSIL Triage Study (ALTS) and the Costa Rica HPV Vaccine Trial (CVT), we compared the early natural history of HPV types to inform transition probabilities for health decision models. We excluded women with evidence of high-grade cervical abnormalities at any point during follow-up and restricted the analysis to incident infections in all women and prevalent infections in young women (aged <30 years).

View Article and Find Full Text PDF
Article Synopsis
  • - The HPV vaccine demonstrates long-lasting effectiveness and stable antibody levels even after just one dose, as shown in a study tracking HPV16 antibody avidity over 11 years among women in Costa Rica who received either one or three vaccine doses.
  • - Women who received only one dose had lower HPV16 antibody avidity compared to those who received three doses, but both groups showed similar patterns of increased avidity in the first three years, remaining stable for the subsequent eight years.
  • - The study found that women who were seropositive for HPV16 at the time of vaccination had lower antibody avidity than seronegative women, but both groups showed similar vaccine efficacy against HPV16 infections, suggesting that even lower avidity levels can still offer
View Article and Find Full Text PDF

Bacterial vaginosis (BV) is a highly prevalent condition that is associated with adverse health outcomes. It has been proposed that BV's role as a pathogenic condition is mediated via bacteria-induced inflammation. However, the complex interplay between vaginal microbes and host immune factors has yet to be clearly elucidated.

View Article and Find Full Text PDF
Article Synopsis
  • HPV vaccination is crucial for preventing cervical cancer in adolescent girls, but many are under-vaccinated due to cost and logistics.
  • Research indicates that a single dose of the HPV vaccine may be as effective as two doses, which led to a large trial comparing the effectiveness of one versus two doses of bivalent and nonavalent vaccines.
  • The ESCUDDO trial, involving over 20,000 girls in Costa Rica, aims to evaluate vaccine efficacy through follow-up visits and comparisons with unvaccinated women.
View Article and Find Full Text PDF