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1.
Int J Cancer ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602045

RESUMO

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.

2.
BMJ Open ; 13(12): e071284, 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-38070892

RESUMO

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.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Síndrome de COVID-19 Pós-Aguda , Costa Rica/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos , Anticorpos , Método Duplo-Cego , Imunidade
3.
Commun Med (Lond) ; 3(1): 102, 2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37481623

RESUMO

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.

4.
Front Med (Lausanne) ; 9: 1006038, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36465901

RESUMO

Background: Replacement of cytology screening with HPV testing is recommended and essential for cervical cancer elimination. HPV testing for primary screening was implemented in 12 laboratories within 9 Latin American countries, as part of the ESTAMPA cervical cancer screening study. Our observations provide information on critical operational aspects for HPV testing implementation in diverse resource settings. Methods: We describe the implementation process of HPV testing in ESTAMPA, focusing on laboratory aspects. We assess the readiness of 12 laboratories to start HPV testing and their continuity capacity to maintain good quality HPV testing until end of recruitment or up to December 2021. Readiness was based on a checklist. Information from the study database; regular meetings and monitoring visits; and a questionnaire on laboratory operational aspects sent in May 2020 were used to assess continuity capacity. Compliance with seven basic requirements (readiness) and eight continuity requirements (continuity capacity) was scored (1 = compliant, 0 = not compliant) and totaled to classify readiness and continuity capacity as very limited, limited, moderate or high. Experiences, challenges, and enablers of the implementation process are also described. Results: Seven of 12 laboratories had high readiness, three moderate readiness, and of two laboratories new to HPV testing, one had limited readiness and the other very limited readiness. Two of seven laboratories with high readiness also showed high continuity capacity, one moderate continuity capacity, and the other four showed limited continuity capacity since they could not maintain good quality HPV testing over time. Among three laboratories with moderate readiness, one kept moderate continuity capacity and two reached high continuity capacity. The two laboratories new to HPV testing achieved high continuity capacity. Based on gained expertise, five laboratories have become part of national screening programs. Conclusion: High readiness of laboratories is an essential part of effective implementation of HPV testing. However, high readiness is insufficient to guarantee HPV testing high continuity capacity, for which a "culture of quality" should be established with regular training, robust monitoring and quality assurance systems tailored to local context. All efforts to strengthen HPV laboratories are valuable and crucial to guarantee effective implementation of HPV-based cervical screening.

5.
Res Sq ; 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36172128

RESUMO

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. Demographic, clinical, and behavioral information was collected from the index cases and their household contacts. 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. To avoid making strong assumptions that the index case was the sole source of infections among household contacts, we fitted a chain binomial model to the serologic data, which allowed us to account for exogenous community infection risk as well as potential multi-generational transmissions within the household. Overall seroprevalence was 53% (95% confidence interval (CI) 48% - 58%) among household contacts The estimated household secondary attack rate (SAR) was 32% (95% CI 5% - 74%) and the average community infection risk was 19% (95% CI 14% - 26%). Mask wearing by the index case was associated with the household transmission risk reduction by 67% (adjusted odds ratio = 0.33 with 95% CI: 0.09-0.75) and sleeping in a separate bedroom from the index case reduced the risk 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 was highly heterogeneous across index cases, with 30% of index cases being the source for 80% of secondary cases. Modeling analysis suggests behavioral factors were important drivers of the observed SARS-CoV-2 transmission heterogeneity within the household.

6.
Vaccine ; 40(1): 76-88, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34857420

RESUMO

HPV vaccination of adolescent girls is the most effective measure to prevent cervical cancer. The World Health Organization recommends that adolescent girls receive two doses of vaccine but only a small proportion of girls from regions with the highest disease burden are vaccinated because of cost and logistical considerations. Our Costa Rica HPV Vaccine trial suggested that one dose of the bivalent HPV vaccine provides robust and lasting protection against persistent HPV infections for over a decade. Data from a post-licensure trial of the quadrivalent vaccine in India also suggested that a single dose may be effective in reducing cervical cancer risk. To formally compare one versus two doses of the bivalent and nonavalent HPV vaccines, we implemented a large, randomized, double-blind trial to investigate the non-inferiority of one compared to two vaccine doses in the prevention of new HPV16/18 infections that persist 6 or more months. Bivalent and nonavalent vaccines will be evaluated separately. The trial enrolled and randomized (1:1:1:1 to 1- and 2-dose arms of the bivalent and nonavalent vaccines) 20,330 girls 12 to 16 years old residing in Costa Rica. Trial participants are followed every 6 months for up to 5 years. We also aim to estimate vaccine efficacy by comparing the rates of 6 month persistent infection in unvaccinated women with the rates in the follow-up visits of trial participants. We included one survey of unvaccinated women at the start of the study (N = 4452) and will include another survey concomitant with follow up visits of trial participants at year 4.5 (planned N = 3000). Survey participants attend two visits 6 months appart. Herein, we present the rationale, design, and enrolled study population of the ESCUDDO trial. ClinicalTrials.gov Identifier: NCT03180034.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Adolescente , Criança , Costa Rica/epidemiologia , Feminino , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Humanos , Papillomaviridae , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Infecção Persistente , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Eficácia de Vacinas
7.
J Psycholinguist Res ; 48(1): 43-59, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29774499

RESUMO

Self-repairs, that is revisions of speech that speakers themselves initiate and complete (Salonen and Laakso in J Child Lang 36:859, 2009. https://doi.org/10.1017/s0305000908009240 ), are frequently used to observe the cognitive and linguistic processes underlying second language (L2) speech production. Previous research has shown that factors such as L2 proficiency, attentional control and native language (L1) self-repair behavior interact with L2 self-repair behavior. To our knowledge, however, no research has examined how these three factors interact within a cohort of L2 speakers. As such, the present study examined the proficiency scores, attentional control scores and L2 and L1 self-repair frequency data of 58 adult L2 English speakers of various proficiency levels. Regression results showed that while proficiency was not a significant predictor of L2 self-repair behavior, attentional control and L1 repair frequency together explained 40% of the variance. Results suggest that L2 self-repair behavior may be more closely linked to stable cognitive and personality traits than to L2 proficiency.


Assuntos
Atenção/fisiologia , Função Executiva/fisiologia , Multilinguismo , Psicolinguística , Fala/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
J Psycholinguist Res ; 41(1): 33-49, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21993899

RESUMO

The present study focuses on the interplay between the linguistic principles and the psycholinguistic processes involved in reading. Results from 56 participants on a letter detection task reveal that readers do not process all function words in the same manner. Omission rates were highest for function words occupying the head of maximal projections such as complementizers and determiners. Prepositions were shown to occupy an intermediary position between content and function words, with omission rates varying depending on their semantic load. Together these results appear to bolster and offer a finer grained picture of the role of function words within the framework of both the Guidance Organization (Greenberg et al. in Psychon Bull Rev 11(3):428-433, 2004) and Attentional Disengagement (Roy-Charland et al. in Percept Psychophys 69(3):324-337, 2007) reading models. The results of the present study are discussed using an X-bar theory approach with the goal of refining the structural account of letter detection errors.


Assuntos
Idioma , Reconhecimento Visual de Modelos/fisiologia , Psicolinguística/métodos , Leitura , Adulto , Humanos , Pessoa de Meia-Idade , Modelos Estatísticos , Teoria Psicológica
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