[Diarrheal disease caused by rotavirus in epidemic outbreaks]. / Enfermedad diarreica por rotavirus en brotes epidémicos.

OBJECTIVE: Determine the epidemiological profile of outbreaks of acute diarrheal disease caused by rotavirus (RV) occurring in pediatric patients, based on a critical review of the literature published between 2000 and 2010. METHODS: A search was carried out for articles published from January 2000 to April 2010, collected by the Artemisa, EBSCO, Embase, Imbiomed, Lilacs, Ovid, PubMed, and Science Direct databases. In the studies that met the inclusion criteria, possible confounding factors were identified and risks of bias were attributed based on the number of items considered inadequate in each case. The epidemiological and microbiological characteristics of the outbreaks were described. RESULTS: The sample was comprised of only 14 (10.8%) of the 129 titles identified, which accounted for 91 092 reported cases of acute diarrhea. In 5 250 of these cases, a search for rotavirus was conducted, yielding 1 711 (32.5%) positive isolations. It was observed that the RV from Group A was the causative agent in 100% of the outbreaks, while genotype G9 was documented in 50% of the articles. CONCLUSIONS: Rotavirus, mainly serotype G9, was one of the principal agents responsible for outbreaks of acute diarrheal disease over the past decade. A careful outbreak study can contribute valuable information for RV disease control and prevention.

Enfermedad diarreica por rotavirus en brotes epidémicos / Diarrheal disease caused by rotavirus in epidemic outbreaks

OBJETIVO: Determinar el perfil epidemiológico de los brotes de enfermedad diarreica aguda por rotavirus (RV) ocurridos en pacientes pediátricos, mediante una revisión crítica de la literatura publicada entre 2000 y 2010. MÉTODOS: Se realizó una búsqueda de artículos publicados desde enero de 2000 hasta abril de 2010, recogidos por las bases de datos Artemisa, EBSCO, Embase, Imbiomed, Lilacs, Ovid, PubMed y Science Direct. En los estudios que cumplieron con los criterios de inclusión, se identificaron posibles factores de confusión y se atribuyeron riesgos de sesgo con base en el número de ítems considerados inadecuados en cada caso. Se describieron las características epidemiológicas y microbiológicas de los brotes. RESULTADOS: Solo 14 (10,8 por ciento) de los 129 títulos identificados formaron parte de la muestra, los cuales sumaron 91 092 casos de diarrea aguda notificados. En 5 250 de estos casos se realizó la búsqueda de RV, la cual arrojó 1 711 (32,5 por ciento) aislamientos positivos. Se observó que el RV del grupo A fue el agente causal en 100 por ciento de los brotes, mientras que el genotipo G9 fue documentado en 50 por ciento de los artículos. CONCLUSIONES: El RV, principalmente el serotipo G9, fue uno de los principales agentes responsables de los brotes de EDA en la última década. Un cuidadoso estudio de brote puede aportar información valiosa para el control y la prevención de la enfermedad por RV.

OBJECTIVE: Determine the epidemiological profile of outbreaks of acute diarrheal disease caused by rotavirus (RV) occurring in pediatric patients, based on a critical review of the literature published between 2000 and 2010. METHODS: A search was carried out for articles published from January 2000 to April 2010, collected by the Artemisa, EBSCO, Embase, Imbiomed, Lilacs, Ovid, PubMed, and Science Direct databases. In the studies that met the inclusion criteria, possible confounding factors were identified and risks of bias were attributed based on the number of items considered inadequate in each case. The epidemiological and microbiological characteristics of the outbreaks were described. RESULTS: The sample was comprised of only 14 (10.8 percent) of the 129 titles identified, which accounted for 91 092 reported cases of acute diarrhea. In 5 250 of these cases, a search for rotavirus was conducted, yielding 1 711 (32.5 percent) positive isolations. It was observed that the RV from Group A was the causative agent in 100 percent of the outbreaks, while genotype G9 was documented in 50 percent of the articles. CONCLUSIONS: Rotavirus, mainly serotype G9, was one of the principal agents responsible for outbreaks of acute diarrheal disease over the past decade. A careful outbreak study can contribute valuable information for RV disease control and prevention.

Enfermedad diarreica por rotavirus en brotes epidémicos / Diarrheal disease caused by rotavirus in epidemic outbreaks

Objetivo. Determinar el perfil epidemiológico de los brotes de enfermedad diarreica aguda por rotavirus (RV) ocurridos en pacientes pediátricos, mediante una revisión crítica de la literatura publicada entre 2000 y 2010. Métodos. Se realizó una búsqueda de artículos publicados desde enero de 2000 hasta abril de 2010, recogidos por las bases de datos Artemisa, EBSCO, Embase, Imbiomed, Lilacs, Ovid, PubMed y Science Direct. En los estudios que cumplieron con los criterios de inclusión, se identificaron posibles factores de confusión y se atribuyeron riesgos de sesgo con base en el número de ítems considerados inadecuados en cada caso. Se describieron las características epidemiológicas y microbiológicas de los brotes. Resultados. Solo 14 (10,8%) de los 129 títulos identificados formaron parte de la muestra, los cuales sumaron 91 092 casos de diarrea aguda notificados. En 5 250 de estos casos se realizó la búsqueda de RV, la cual arrojó 1 711 (32,5%) aislamientos positivos. Se observó que el RV del grupo A fue el agente causal en 100% de los brotes, mientras que el genotipo G9 fue documentado en 50% de los artículos. Conclusiones. El RV, principalmente el serotipo G9, fue uno de los principales agentes responsables de los brotes de EDA en la última década. Un cuidadoso estudio de brote puede aportar información valiosa para el control y la prevención de la enfermedad por RV.

Objective. Determine the epidemiological profile of outbreaks of acute diarrheal disease caused by rotavirus (RV) occurring in pediatric patients, based on a critical review of the literature published between 2000 and 2010. Methods. A search was carried out for articles published from January 2000 to April 2010, collected by the Artemisa, EBSCO, Embase, Imbiomed, Lilacs, Ovid, PubMed, and Science Direct databases. In the studies that met the inclusion criteria, possible confounding factors were identified and risks of bias were attributed based on the number of items considered inadequate in each case. The epidemiological and microbiological characteristics of the outbreaks were described. Results. The sample was comprised of only 14 (10.8%) of the 129 titles identified, which accounted for 91 092 reported cases of acute diarrhea. In 5 250 of these cases, a search for rotavirus was conducted, yielding 1 711 (32.5%) positive isolations. It was observed that the RV from Group A was the causative agent in 100% of the outbreaks, while genotype G9 was documented in 50% of the articles. Conclusions. Rotavirus, mainly serotype G9, was one of the principal agents responsible for outbreaks of acute diarrheal disease over the past decade. A careful outbreak study can contribute valuable information for RV disease control and prevention.

Congenital syphilis, a reemergent disease in Mexico: its epidemiology during the last 2 decades.

OBJECTIVE: To describe the epidemiologic profile of congenital syphilis in Mexico between 1990 and 2009. METHODS: The database of the General Direction of Epidemiology at the Ministry of Health in Mexico about congenital syphilis was reviewed. Data corresponding to the period between 1990 and 2009 were analyzed in every state of the Mexican republic. RESULTS: A total of 1717 cases of congenital syphilis were reported during the study period. A 16.6% increase was observed between 2005 and 2009 and the quinquennium between 2000 and 2004. A trend toward increase in the incidence of congenital syphilis was observed with 2.9 new cases for each 100,000 babies born alive. The states that displayed significant positive trends were as follows: Baja California, Colima, Chihuahua, Jalisco, Nayarit, Sinaloa, and Zacatecas. CONCLUSIONS: An increase in the number of cases of congenital syphilis is observed; the northern states are the ones that contribute the most to the statistics. There is a real need to refine the epidemiologic operations to detect and treat the cases of maternal and congenital syphilis in the country.

Intussusception risk and health benefits of rotavirus vaccination in Mexico and Brazil.

BACKGROUND: Because postlicensure surveillance determined that a previous rotavirus vaccine, RotaShield, caused intussusception in 1 of every 10,000 recipients, we assessed the association of the new monovalent rotavirus vaccine (RV1) with intussusception after routine immunization of infants in Mexico and Brazil. METHODS: We used case-series and case-control methods to assess the association between RV1 and intussusception. Infants with intussusception were identified through active surveillance at 69 hospitals (16 in Mexico and 53 in Brazil), and age-matched infants from the same neighborhood were enrolled as controls. Vaccination dates were verified by a review of vaccination cards or clinic records. RESULTS: We enrolled 615 case patients (285 in Mexico and 330 in Brazil) and 2050 controls. An increased risk of intussusception 1 to 7 days after the first dose of RV1 was identified among infants in Mexico with the use of both the case-series method (incidence ratio, 5.3; 95% confidence interval [CI], 3.0 to 9.3) and the case-control method (odds ratio, 5.8; 95% CI, 2.6 to 13.0). No significant risk was found after the first dose among infants in Brazil, but an increased risk, albeit smaller than that seen after the first dose in Mexico--an increase by a factor of 1.9 to 2.6 - was seen 1 to 7 days after the second dose. A combined annual excess of 96 cases of intussusception in Mexico (approximately 1 per 51,000 infants) and in Brazil (approximately 1 per 68,000 infants) and of 5 deaths due to intussusception was attributable to RV1. However, RV1 prevented approximately 80,000 hospitalizations and 1300 deaths from diarrhea each year in these two countries. CONCLUSIONS: RV1 was associated with a short-term risk of intussusception in approximately 1 of every 51,000 to 68,000 vaccinated infants. The absolute number of deaths and hospitalizations averted because of vaccination far exceeded the number of intussusception cases that may have been associated with vaccination. (Funded in part by the GAVI Alliance and the U.S. Department of Health and Human Services.).

Relevance of Helicobacter pylori virulence factors for vaccine development.

Helicobacter pylori infection increases the risk for a wide spectrum of clinical outcomes, ranging from peptic ulcer disease to gastric cancer. However, the infection induces gastric and duodenal ulceration or gastric cancer in only a minority of infected subjects because H. pylori strains are genetically diverse and express different virulence factors. Individuals infected with strains that express these virulence factors probably develop severe diseases such as gastric cancer. Nevertheless, the ancient relationship between H. pylori and humans suggests that some strains could be beneficial to human health, which means that generalized administration of antibiotic therapy could eventually cause problems. The development of vaccines based on virulence factors that provide long-term protection is the best strategy for control and/or elimination of pathogenic strains. The different immunization schemes and formulations designed to evaluate the vaccines based on virulence factors in animal models have offered promising results. However, it is necessary to determine whether or not these results can be reproduced in humans. This article reviews recent vaccination studies that explore this possibility: oral vaccines using urease or inactivated whole cells plus LT as adjuvant and urease expressed in Salmonella spp. vectors, as well as a parenteral multicomponent vaccine plus aluminum hydroxide as adjuvant. Although these studies have achieved limited success, they have established support for the development of an effective vaccine against this infection.

Relevance of Helicobacter pylori virulence factors for vaccine development / Relevancia de los factores de virulencia de helicobacter pylori para el desarrollo de vacunas

Helicobacter pylori infection increases the risk for a wide spectrum of clinical outcomes, ranging from peptic ulcer disease to gastric cancer. However, the infection induces gastric and duodenal ulceration or gastric cancer in only a minority of infected subjects because H. pylori strains are genetically diverse and express different virulence factors. Individuals infected with strains that express these virulence factors probably develop severe diseases such as gastric cancer. Nevertheless, the ancient relationship between H. pylori and humans suggests that some strains could be beneficial to human health, which means that generalized administration of antibiotic therapy could eventually cause problems. The development of vaccines based on virulence factors that provide long-term protection is the best strategy for control and/or elimination of pathogenic strains. The different immunization schemes and formulations designed to evaluate the vaccines based on virulence factors in animal models have offered promising results. However, it is necessary to determine whether or not these results can be reproduced in humans. This article reviews recent vaccination studies that explore this possibility: oral vaccines using urease or inactivated whole cells plus LT as adjuvant and urease expressed in Salmonella spp. vectors, as well as a parenteral multicomponent vaccine plus aluminum hydroxide as adjuvant. Although these studies have achieved limited success, they have established support for the development of an effective vaccine against this infection.

La infección por Helicobacter pylori incrementa el riesgo de un amplio espectro de cuadros clínicos, que van de la úlcera péptica al cáncer gástrico. Sin embargo, la infección sólo induce ulceración gástrica y duodenal o cáncer gástrico en la minoría de los sujetos infectados debido que las cepas de H. pylori son genéticamente diversas y expresan diferentes factores de virulencia. Así, los individuos infectados por cepas que expresan estos factores de virulencia probablemente desarrollan enfermedades severas como el cáncer gástrico. Sin embargo, la ancestral relación entre H. pylori y los humanos sugiere que algunas cepas pueden ser beneficiosas para la salud humana. Por lo tanto, la administración generalizada de tratamientos con antibiótico podría eventualmente causar problemas. El desarrollo de vacunas con base en factores de virulencia que confieran protección a largo plazo es la mejor estrategia para el control y/o eliminación de cepas patógenas. Los diferentes esquemas y formulaciones de inmunización diseñados para evaluar las vacunas con base en factores de virulencia en modelos animales han dado resultados prometedores. Sin embargo, ha sido necesario probar si estos resultados pueden ser reproducidos en humanos. Este trabajo revisa los recientes estudios de vacunación que han explorado esta posibilidad: vacunas orales usando ureasa o células completas-inactivadas con LT como adyuvante y ureasa expresada en vectores de Salmonella spp.; además de una vacuna intramuscular multicomponente con hidróxido de aluminio como adyuvante. Aunque estos estudios han logrado limitado éxito han establecido las bases para el desarrollo de una vacuna eficaz contra esta infección.