Vaccination herd effect experience in Latin America: a systematic literature review.

BACKGROUND: National pediatric vaccination programs have been introduced in Latin America (LatAm) to reduce the burden of diseases due to pathogens such as rotavirus, Haemophilus influenzae type b (Hib) and pneumococcus. Vaccination health benefits may extend to unvaccinated populations by reducing pathogen transmission. Understanding herd effect is important for implementation and assessment of vaccination programs. The objective was to conduct a systematic review of published epidemiological evidence of herd effect with Hib, rotavirus and pneumococcal conjugate vaccines (PCV) in LatAm. METHODS: Searches were conducted in PubMed, Virtual Health Library (VHL), SciELO and SCOPUS databases, for studies reporting data on herd effect from Hib, rotavirus and PCV vaccination in LatAm, without age restriction. Searches were limited to articles published in English, Spanish or Portuguese (1990-2016). After screening and full-text review, articles meeting the selection criteria were included to be critically appraised following criteria for observational and interventional studies. The presence of a herd effect was defined as a significant decrease in incidence of disease, hospitalization, or mortality. RESULTS: 3,465 unique articles were identified, and 23 were included (Hib vaccine n = 5, PCV n = 8, rotavirus vaccine n = 10). Most studies included children and/or adolescents (age range varied between studies). Studies in adults, including older adults (aged > 65 years), were limited. Few studies reported statistically significant reductions in disease incidence in age groups not targeted for vaccination. Hib-confirmed meningitis hospitalization decreased in children but herd effect could not be quantified. Some evidence of herd effect was identified for PCV and rotavirus vaccine in unvaccinated children. Evidence for herd effects due to PCV in adults was limited. CONCLUSION: After introduction of Hib, PCV and rotavirus vaccination in LatAm, reductions in morbidity/mortality have been reported in children not targeted for vaccination. However, due to methodological limitations (e.g. short post-vaccination periods and age range studied), there is currently insufficient evidence to quantify the herd effect in adult populations. More research and higher quality surveillance is needed to characterize herd effect of these vaccines in LatAm.

Patología de cuello uterino en adolescentes con vida sexual activa / Uterine cervical pathology in sexually active adolescents

Conocer la frecuencia de patología de cuello en las adolescentes que acudieron a la consulta de Ginecología Infantil Juvenil del Hospital "Dr. Domingo Luciani", durante el período septiembre 2001 a septiembre de 2002. Se realizó un estudio descriptivo, y prospectivo. La muestra estuvo constituida por 125 pacientes, con edades entre 14-19 años, la edad promedio fue 17,28 años. Las citologías reportaron inflamación inespecíficas (58.4%), inflamación específicas (32%) y de éstas el 57% presentó Garnerella, 25% Cándida, 12,5 Tricomona y 5% Leptotrix. 95 colposcopias fueron normales (76%), 12 (10%) insatisfactorias y 18 (14%) reportaron epitelio blanco. De 18 biopsias 14 no presentaron lesiones (78%) y 4 (22%) reportaron VPH, a éstas se les realizó PCR, siendo negativas. Las adolescentes representan un grupo de riesgo por lo que se deben establecer programa sanitario para despistaje de patología de cuello, programas escolares para evitar ETS y orientar a las pacientes de riesgo elevado para tener un adecuado control ginecológico.

[Complications and costs associated with chickenpox in immunocompetent children]. / Complicaciones y costos asociados a la varicela en niños inmunocompetentes.

OBJECTIVES: Chickenpox is a common infection of childhood in countries that have not included the corresponding vaccination in their immunization schedules. Chickenpox is usually benign in immunocompetent children, and treatment is not needed. The objectives of this study were to investigate the frequency and characteristics of chickenpox complications that require hospital treatment in immunocompetent children and the clinical progression in children of mothers with perinatal chickenpox. In addition, the hospital costs associated with chickenpox in the studied children were calculated. METHODS: This was a retrospective study using the clinical records of children with chickenpox hospitalized at the Children's Hospital of Panama, from January 1991 through December 2000. We analyzed the types of complications, the clinical progression, and the hospital costs of the chickenpox patients. RESULTS: Of 5 203 children seen in outpatient consultations, 568 of them (11%) were hospitalized. We included 513 children in our study: 381 (74%) with chickenpox acquired in the community, 92 (18%) the children of mothers with chickenpox, and 40 (8%) with nosocomial chickenpox. The most frequent complications were cutaneous and subcutaneous infections (45%), respiratory infections (25%), and neurological changes (7%). The respiratory and cutaneous complications occurred sooner and among younger patients than did the neurological changes. Overall, 13 of the children (2.5%) died. The case fatality rate was 8% for chickenpox with respiratory and neurological complications and 0% for chickenpox with cutaneous complications. Of the 92 children with a mother with chickenpox, 60 of them (65%) did not develop the disease, and none of the 92 died. In contrast, 2 of the 32 neonates (6%) with perinatal chickenpox died. The mean length of hospitalization was 8.9 days (standard deviation, +/- 17.4 days). Parenteral pharmacotherapy was used with the great majority of the children, particularly antibiotics (54%), acyclovir (17%), and intravenous immunoglobulin (14%). The mean per-patient cost of hospitalization was US$ 1 209. CONCLUSIONS: Our results show that chickenpox is associated with a sizable number of expensive complications and a not-insignificant case fatality rate in immunocompetent children. Routine vaccination against chickenpox could reduce the impact of this disease on the health of children in Panama

Prevalencia de anticuerpos contra hepatitis A (anti-HVA IgG) en una población de 01 a 39 años de Lima / Anti-Hav IgG prevalence in a popultion between 1 and 39 years old in Lima, Peru

La prevalencia de la infección por el virus de hepatitis A (VHA) en un país es un indicador de su nivel de higiene y condiciones socioeconómicos. En la década del 80 se reportaron en Lima una prevalencia de 98 por ciento del anti-HVA en adultos y de 82 por ciento en los niños, con un rango de 30 por ciento al año de edad y 100 por ciento a los 8 años. Entre octubre y diciembre de 1999, realizamos una encuesta sero-epidemiológica para evaluar la presencia de anticuerpos contra el virus de hepatitis A de tipo IgG en 859 sujetos entre 1 y 39 años, divididas en dos grupos de acuerdo a su status socioeconómico. En la población adulta estudiada (menor de 20 años) se encontró una positividad anti-HAV de 84 por ciento (288/341), mientras que en la población infantil (menor de 14 años) se encontró 46.3 por ciento(163/352); siendo los de nivel socio-económico AB los mas bajos: 35.6 por ciento (57/160) y los del nivel CD de 55.2 por ciento (106/192). Concluimos que en los últimos 15 años se ha producido una significativa reducción de la prevalencia del anti-HVA en la población infantil y adolescente de Lima, lo que configura un patrón epidemiológico de endemicidad intermedia.