Vaccine effectiveness in reducing COVID-19-related hospitalization after a risk-age-based mass vaccination program in a Chilean municipality: A comparison of observational study designs.

BACKGROUND: Case-control studies involving test-negative (TN) and syndrome-negative (SN) controls are reliable for evaluating influenza and rotavirus vaccine effectiveness (VE) during a random vaccination process. However, there is no empirical evidence regarding the impact in real-world mass vaccination campaigns against SARS-CoV-2 using TN and SN controls. OBJECTIVE: To compare in the same population the effectiveness of SARS-CoV-2 vaccination on COVID-19-related hospitalization rates across a cohort design, TN and SN designs. METHOD: We conducted an unmatched population-based cohort, TN and SN case-control designs linking data from four data sources (public primary healthcare system, hospitalization registers, epidemiological surveillance systems and the national immunization program) in a Chilean municipality (Rancagua) between March 1, 2021 and August 31, 2021. The outcome was COVID-19-related hospitalization. To ensure sufficient sample size in the unexposed group, completion of follow-up in the cohort design, and sufficient time between vaccination and hospitalization in the case-control design, VE was estimated comparing 8-week periods for each individual. RESULTS: Among the 191,505 individuals registered in the primary healthcare system of Rancagua in Chile on March 1, 2021; 116,453 met the cohort study's inclusion criteria. Of the 9,471 hospitalizations registered during the study period in the same place, 526 were COVID-19 cases, 108 were TN controls, and 1,628 were SN controls. For any vaccine product, the age- and sex-adjusted vaccine effectiveness comparing fully and nonvaccinated individuals was 67.2 (55.7-76.3) in the cohort design, whereas it was 67.8 (44.1-81.4) and 77.9 (70.2-83.8) in the TN and SN control designs, respectively. CONCLUSION: The VE of a COVID-19 vaccination program based on age and risk groups tended to differ across the three observational study designs. The SN case-control design may be an efficient option for evaluating COVID-19 VE in real-world settings.

Detection and genotyping of HPV in urine samples from Chilean women attending primary health care centers.

Cervical cancer is the second most common malignant neoplasm in women worldwide representing approximately 10% of all types of cancers. Triage of women through cervical cytology has been an important strategy for the surveillance and control of new cases of cervical cancer. However, in many regions around the world cervical cytology has a low coverage compared to developed countries. The molecular detection of HPV is the most effective method to increase the screening sensitivity of women at risk of developing cervical cancer. There are very few studies about the efficacy of urine testing for detection of HPV in women followed up in primary health care centers. Consequently, the efficacy of using urine HPV screening in these populations has not been addressed yet. Here, we compared the detection of HPV in simultaneous urine and cervical samples of women followed up in primary health care centers. Urine and cervical samples were analyzed in 543 women attending at primary health care centers. HPV was detected by real time PCR, and HPV typing performed by PCR-RLB. A general HPV concordance of 86.2% (κ = 0.72) was determined between urine and cervical samples. The concordance for HPV-16 and 18 was almost perfect (κ = 0.82) and strong (κ = 0.77), respectively. The sensitivity and specificity for all HPV genotypes in urine using cervical samples as reference were 82.1 and 93.7%, respectively. The results showed that urine is a good alternative as clinical sample for HPV screening in women attending primary health care centers. Therefore, urine should be used as an alternative sample for increasing triage coverage either in refractory women participating in Pap surveillance programs or when cervical samples are not available.

Enseñanza de la atención del parto vaginal utilizando simuladores / Teaching vaginal delivery care using simulators

La simulación en docencia en ciencias de la salud, permite integrar conocimientos y desarrollar habilidades previo a la práctica clínica, logrando competencias complejas. Además, permite a los estudiantes implementar un cuidado personalizado, pensar críticamente y mejorar la confianza en sus capacidades. Objetivo: evaluar la contribución de la simulación de la atención del parto, en la adquisición de una habilidad esencial para alumnos que optan a desempeñarse en el área obstétrica. Materiales y métodos: se realizó una búsqueda bibliográfica basada en datos PubMed que incluyó las palabras claves simulation, labor y education y sus equivalentes en español. Se excluyeron los títulos relacionados con "anestesia en obstetricia" y "hemorragia postparto". Se revisaron investigaciones observacionales, descriptivos, revisiones narrativas y sistemáticas, ensayos controlados, estudios cuasi experimentales y prospectivos. Resultados: Se seleccionaron 50 artículos que contenían al menos una de las palabras clave y estaban relacionados con "obstetricia" o "parto", logrando acceder a 46 de ellos. La simulación de parto es una estrategia educativa exitosa, que permite a los alumnos sentirse más confiados, mejora el trabajo en equipo, incrementa el grado de conocimiento, mejora habilidades y permite cuidar a las usuarias sin riesgos. Conclusiones: la simulación es un método educativo que permite a los estudiantes practicar lo aprendido en clases antes de iniciar la experiencia clínica, disminuyendo el riesgo de la atención de pacientes por alumnos. Se recomienda el uso de la simulación en la docencia de atención del parto vaginal como una herramienta exitosa que contribuye en la adquisición de habilidades clínicas.(AU)

Simulation in health sciences education allows knowledge integration and skills development before clinical practice,achieving complex skills. Also, simulation enhances students personalized care attitude, think critically and gain confidence. Objective: we aim to attest to the contribution of childbirth simulation in the acquisition of essential proficiency for midwifery students. Materials and methods: we conducted a bibliographic search in the PubMed database, using the keywords: simulation, labor, and education, either in English or Spanish. We excluded articles related to obstetric anesthesia and postpartum hemorrhage. We reviewed observational, descriptive, narrative and systematic reviews, controlled trials, quasi-experimental and prospective studies. Results: we select fifty articles, obtaining access to 46 of them. Childbirth simulation educational strategy, improving student's self-confidence, teamwork, knowledge, clinical skills and lowering patient´s risks. Conclusions: simulation is an educational method that allows students to practice what they have learned in class before starting the clinical experience, decreasing the risk of patient care by students The use of simulation in teaching vaginal delivery care is recommended as a successful tool in the acquisition of clinical skills.(AU)

Effectiveness of the 10-Valent Pneumococcal Conjugate Vaccine (PCV-10) in Children in Chile: A Nested Case-Control Study Using Nationwide Pneumonia Morbidity and Mortality Surveillance Data.

BACKGROUND: The ten-valent pneumococcal conjugate vaccine (PCV10) was introduced into the Chilean National Immunization Program (NIP) in January 2011 with a 3+1 schedule (2, 4, 6 and 12 months) without catch-up vaccination. We evaluated the effectiveness of PCV10 on pneumonia morbidity and mortality among infants during the first two years after vaccine introduction. METHODS: This is a population-based nested case-control study using four merged nationwide case-based electronic health data registries: live birth, vaccination, hospitalization and mortality. Children born in 2010 and 2011 were followed from two moths of age for a period of two years. Using four different case definitions of pneumonia hospitalization and/or mortality (all-cause and pneumonia related deaths), all cases and four randomly selected matched controls per case were selected. Controls were matched to cases on analysis time. Vaccination status was then assessed. Vaccine effectiveness (VE) was estimated using conditional logistic regression. RESULTS: There were a total of 497,996 children in the 2010 and 2011 Chilean live-birth cohorts. PCV10 VE was 11.2% (95%CI 8.5-13.6) when all pneumonia hospitalizations and deaths were used to define cases. VE increased to 20.7 (95%CI 17.3-23.8) when ICD10 codes used to denote viral pneumonia were excluded from the case definition. VE estimates on pneumonia deaths and all-cause deaths were 71.5 (95%CI 9.0-91.8) and 34.8 (95% CI 23.7-44.4), respectively. CONCLUSION: PCV10 vaccination substantially reduced the number of hospitalizations due to pneumonia and deaths due to pneumonia and to all-causes over this study period. Our findings also reinforce the importance of having quality health information systems for measuring VE.

Prevalence of meningococcal carriage in children and adolescents aged 10-19 years in Chile in 2013.

In 2011, Chile experienced an increase in the number of cases of IMD caused by Neisseria meningitidis group W. This epidemiological scenario prompted authorities to implement prevention strategies. As part of these strategies, the Institute of Public Heath of Chile conducted a cross-sectional study to determine the prevalence of pharyngeal carriage of N. meningitidis in a representative sample of healthy children and adolescents aged 10-19 years. The identification of presumptive N. meningitidis strains was performed by testing carbohydrate utilization in the National Reference Laboratory at the ISP. Association of meningococcal carriage with risk factors was analyzed by calculating the Odds Ratio. Selected variables were included in a logistic model for risk analyses. The prevalence of carriage of N. meningitidis was 6.5% (CI: 5.7-7.3%). Older age (carriers: 14.2±0.29 vs. non-carriers: 13.8±0.08 years old; p=0.009), cohabitation with children (carriers: 0.9±0.13 vs. non-carriers: 0.7±0.03; p=0.028), number of smoking cohabitants (carriers: 0.55±0.13 vs. non-carriers: 0.44±0.03) and frequent attendance to crowded social venues (carriers: 49% vs. non-carriers: 37%; p=0.008) were determined to favor carriage. Statistical modeling showed that meningococcal carriage was associated with older age (OR: 1.077, p-value: 0.002) and cohabitation with children (OR: 1.182, p-value: 0.02).

Neisseria meningitidis ST-11 clonal complex, Chile 2012.

Serogroup W Neisseria meningitidis was the main cause of invasive meningococcal disease in Chile during 2012. The case-fatality rate for this disease was higher than in previous years. Genotyping of meningococci isolated from case-patients identified the hypervirulent lineage W:P1.5,2:ST-11, which contained allele 22 of the fHbp gene.

Molecular characterization of invasive Neisseria meningitidis strains isolated in Chile during 2010-2011.

BACKGROUND: With the upcoming licensure of Outer Membrane Protein-based vaccines against meningococcal disease, data on disease incidence and molecular characteristic of circulating N. meningitidis strains in Latin American countries is needed. Chile is, to date, one of the few countries in the region that has performed this type of work in a comprehensive collection of disease-associated strains from two consecutive years, 2010-2011. METHODS: A total of 119 N. meningitidis strains isolated from patients with invasive disease in Chile in 2010-2011 were characterized by the National Reference Laboratory. Serogroup determination, MLST and porA typing were performed. RESULTS: Serogroup B was predominant in both study years, but W135 experienced a noticeable increase in 2011 compared to 2010. ST-11 complex, ST-41/44 complex ST-32 complex were the most prevalent among the isolates, and were strongly associated with serogroups W135 (ST-11 Complex) and B (ST-41/44 and ST-32 complexes). Likewise, the major porA types detected were strongly associated with these three clonal complexes: P1.5,2 was found exclusively among W135:ST-11 isolates, whereas P1.7, 2-3 was only detected in C:ST-11. ST-41/44 isolates mainly had P1.10-8, and ST-32 complex were associated with a P1.18-8 porA. CONCLUSIONS: Our data show disease-associated N. meningitidis circulating in Chile are similar to those found in other parts of the world. The increase on W135:ST-11 isolates observed in 2011 foretold the unusual epidemiological situation experienced in the country in 2012, and MLST data show that this strain is indistinguishable from the one linked to the global Hajj 2000-related outbreak that occurred in 2001. Finally, this work demonstrates the importance of maintaining a strong national surveillance program integrating clinical, epidemiological and laboratory data and incorporating gold standard diagnostic and characterization techniques that allow the data to be compared all over the world.

Determinación de resistencia inicial del mycobacterium tuberculosis a las drogas de retratamiento / Assesment of initial resistance of mycobacterium tuberculosis to retreatment antituberculosis drugs

Se determinó la resistencia inicial a las drogas de retratamiento Etambutol, Kanamicina y Ethionamida, en 260 primocultivos provenientes de pacientes con tuberculosis de distintas localizaciones, principalmente pulmonar. La resistencia encontrada en 107 pacientes con fracaso terapéutico al esquema nacional (S-H-R-Z) fue de 14% a diferencia de un 2% detectado en 153 casos nuevos. Este hallazgo es de alto interés clínico, por lo que se sugiere conocer el patrón de sensibilidad a las drogas de retratamiento de toda cepa proveniente de los pacientes con fracaso terapéutico

Análisis retrospectivo del pronóstico de la meningitis tuberculosa en Chile, en relación al diagnóstico y al tratamiento / Retrospective analysis from prognosis of tuberculous meningitis in Chile, in relation to diagnosis and therapy

Con el objeto de conocer los factores pronósticos de la meningitis tuberculosa y medir la eficacia de los esquemas terapéuticos en Chile, se analizaron mediante una encuesta retrospectiva 43 casos de meningitis tuberculosa diagnosticados bacteriológicamente por cultivo entre 1983 y 1986, y que correspondieron al 65.2% del total de pacientes notificados confirmados por cultivo del bacilo de Koch en ésos años. La encuesta consideró los antecedentes, cuadro clínico, examen citoquímico del LCR, estudio de sensibilidad a las drogas antituberculosas, tratamiento y evolución de cada paciente. El seguimiento mostró que el 55,8% de los pacientes (n=24) fueron dados de alta como inactivos, de los cuales 10 (41,7%) egresaron con secuelas neurológicas, algunas invalidantes. La letalidad fué del 32,6%, y correspondió a 14 fallecidos, 12 de los cuales lo hicieron con menos de una semana de tratamiento. Este mal pronóstico de la enfermedad observado es explicado por: 1) el estado clínico al ingreso: 100% de los pacientes (n=5) en etapa III fallecieron, 2) otras localizaciones concomitantes de tuberculosis, observadas en un 56% de los casos, 3) la presencia de una elevada drogo-resistencia inicial (20%) y 4) la edad de los pacientes, ya que hubo una mayor letalidad en los extremos de la vida. La terapia, evaluada en 27 pacientes (24 que recibieron un esquema acortado con Estreptomicina-Isoniacida-Rifampicina y Piracinamida durante un tiempo adecuado, tres en que hubo que modificar éste esquema), se consideró satisfactoria, ya que sólo hubo un fracaso y fallecieron 2 pacientes que alcanzaron a recibir 48 y 50 dosis diarias de tratamiento respectivamente

Avances en el diagnóstico precoz de la meningitis tuberculosa / Advances in the early diagnosis of tuberculous meningitis

El aislamiento de mycobacterium tuberculosis en el líquido cefalorraquídeo, mediante el cultivo se logra sólo en alrededor de 30-40% de los casos de meningitis tuberculosa. Se sabe que el pronóstico de la enfermedad se encuentra ligado a la precocidad del diagnóstico, pues así se evita el avance de la enfermedad hacia estados más graves. Los intentos por encontrar métodos de diagnóstico más rápidos han sido múltiples. En éste artículo se analizan los fundamentos, sensibilidad y especificidad de métodos directos que miden productos del microorganismo causal de la enfermedad, tales como la detección de antígenos mycobacterianos y la identificación bioquímica de sus productos de degradación. También hay métodos indirectos que miden productos de la respuesta del huésped a la infección, es decir, anticuerpos a diversos antígenos mycobacterianos. En países en vías de desarrollo se recomienda que por su sencillez y bajo costo se implementen técnicas adicionales a la bacteriología tales como la determinación de la actividad de adenosin-deaminasa y enzimo inmuno-análisis (ELISA) para la detección de antígenos o anticuerpos contra el mycobacterium tuberculosis

El hábito de fumar en un grupo de embarazadas de tres comunidades rurales / Smoking in a group of pregnant women of 3 rural communities

Se estudió el hábito de fumar, sus modificaciones durante el embarazo y el peso del Recién Nacido. El grupo de estudio corresponde a 232 madres rurales que ingresaron a control prenatal en el segundo semestre de 1986 en los Consultorios de Doñihue, Coltauco y Hospital Coinco. Se concluye que: 1. El porcentaje de madres que fuman durante el embarazo es bajo (9,5%). 2. El inicio del hábito de fumar en las mujeres es precoz. 3. En relación a los pesos de nacimiento se demostró que el hábito de fumar tiene un efecto significativo en los pesos menores de 3.000 grs, que se encuentran en mayor proporción en los hijos de embarazadas fumadoras