16S rRNA Gene-targeted TTGE in Determining Diversity of Gut Microbiota during Acute Diarrhoea and Convalescence.

The human gut microbiota play a vital role in health and nutrition but are greatly modified during severe diarrhoea due to purging and pathogenic colonization. To understand the extent of loss during and after diarrhoea, faecal samples collected from children (n=21) suffering from acute diarrhoea and from their healthy siblings (n=9) were analyzed by 16S rRNA gene-targeted universal primer polymerase chain reaction (PCR), followed by temporal temperature gradient gel electrophoresis (TTGE). The gut microbiota decreased significantly as indicated by the number of TTGE bands at day 0 of acute diarrhoea [patients vs healthy siblings: 11±0.9 vs 21.8±1.1 (mean±standard error), p<0.01]. The number of bands showed a steady increase from day 1 to day 7; however, it remained significantly less than that in healthy siblings (15±0.9, p<0.01). These results suggest that appropriate therapeutic and post-diarrhoeal nutritional intervention might be beneficial for the early microbial restoration and recovery.

Nutrition of Children and Women in Bangladesh: Trends and Directions for the Future.

Although child and maternal malnutrition has been reduced in Bangladesh, the prevalence of underweight (weight-for-age z-score <-2) among children aged less than five years is still high (41%). Nearly one-third of women are undernourished with body mass index of <18.5 kg/m2. The prevalence of anaemia among young infants, adolescent girls, and pregnant women is still at unacceptable levels. Despite the successes in specific programmes, such as the Expanded Programme on Immunization and vitamin A supplementation, programmes for nutrition interventions are yet to be implemented at scale for reaching the entire population. Given the low annual rate of reduction in child undernutrition of 1.27 percentage points per year, it is unlikely that Bangladesh would be able to achieve the United Nations’ Millennium Development Goal to address undernutrition. This warrants that the policy-makers and programme managers think urgently about the ways to accelerate the progress. The Government, development partners, non-government organizations, and the academia have to work in concert to improve the coverage of basic and effective nutrition interventions, including exclusive breastfeeding, appropriate complementary feeding, supplementation of micronutrients to children, adolescent girls, pregnant and lactating women, management of severe acute malnutrition and deworming, and hygiene interventions, coupled with those that address more structural causes and indirectly improve nutrition. The entire health system needs to be revitalized to overcome the constraints that exist at the levels of policy, governance, and service-delivery, and also for the creation of demand for the services at the household level. In addition, management of nutrition in the aftermath of natural disasters and stabilization of prices of foods should also be prioritized.

The 2008 Cholera Epidemic in Zimbabwe: Experience of the icddr,b Team in the Field.

During August 2008–June 2009, an estimated 95,531 suspected cases of cholera and 4,282 deaths due to cholera were reported during the 2008 cholera outbreak in Zimbabwe. Despite the efforts by local and international organizations supported by the Zimbabwean Ministry of Health and Child Welfare in the establishment of cholera treatment centres throughout the country, the case-fatality rate (CFR) was much higher than expected. Over two-thirds of the deaths occurred in areas without access to treatment facilities, with the highest CFRs (>5%) reported from Masvingo, Manicaland, Mashonaland West, Mashonaland East, Midland, and Matabeleland North provinces. Some factors attributing to this high CFR included inappropriate cholera case management with inadequate use of oral rehydration therapy, inappropriate use of antibiotics, and a shortage of experienced healthcare professionals. The breakdown of both potable water and sanitation systems and the widespread contamination of available drinking-water sources were also considered responsible for the rapid and widespread distribution of the epidemic throughout the country. Training of healthcare professionals on appropriate cholera case management and implementation of recommended strategies to reduce the environmental contamination of drinking-water sources could have contributed to the progressive reduction in number of cases and deaths as observed at the end of February 2009.

Global Health Education: International Collaboration at ICDDR,B.

The purpose of this commentary is to provide an overview of the growing interest in global health education at ICDDR,B and to review examples of how this has grown from public-health research and education to include clinical education (medical and nursing) as well. This parallels the growth of the institution, with an increased focus on educational linkages within and beyond Bangladesh and the rise in interest in global health at western medical schools. Specific collaborations, their setup and structure are described. This is presented as a model for other centres of excellence in developing countries to engage their partners in the South and North on matters of education and research for mutual cooperation and benefit.

Serogroups, K1 antigen, and antimicrobial resistance patterns of Aeromonas spp. strains isolated from different sources in Mexico

A total of 221 strains of Aeromonas species isolated in Mexico from clinical (161), environmental (40), and food (20) samples were identified using the automated system bioMérieux-Vitek®. Antisera for serogroups O1 to 044 were tested using the Shimada and Sakazaki scheme. The K1 antigen was examined using as antiserum the O7:K1C of Escherichia coli. Besides, we studied the antimicrobial patterns according to Vitek AutoMicrobic system. Among the 161 clinical strains 60 percent were identified as A. hydrophila, 20.4 percent as A. caviae, and 19.25 percent as A. veronii biovar sobria. Only A. hydrophila and A. veronii biovar sobria were found in food (55 and 90 percent respectively) and environmental sources (45 and 10 percent respectively). Using "O" antisera, only 42.5 percent (94/221) of the strains were serologically identified, 55 percent (121/221) were non-typable, and 2.5 percent (6/221) were rough strains. Twenty-two different serogroups were found, O14, O16, O19, O22, and O34 represented 60 percent of the serotyped strains. More than 50 percent of Aeromonas strain examined (112/221) expressed K1 encapsulating antigen; this characteristic was predominant among Aeromonas strains of clinical origin. Resistance to ampicillin/sulbactam and cephazolin was detected in 100 and 67 percent of Aeromonas strain tested for their susceptibility to antibiotics. In conclusion, antibiotic-resistant Aeromonas species that possess the K1 encapsulating antigen and represent serogroups associated with clinical syndrome in man are not uncommon among Aeromonas strains isolated from clinical, food and environmental sources in Mexico.

Abortion, contraceptive use, and adolescent pregnancy among first-year medical students at a major public university in Mexico City

OBJECTIVE: If properly trained, medical students could become future opinion leaders in health policy and could help the public to understand the consequences of unwanted pregnancies and of abortions. The objective of this study was to analyze the frequency of unwanted pregnancies and induced abortions that had occurred among women who were first-year medical students at a major public university in Mexico City and to compare the experiences of those women with the experiences of the general population of Mexican females aged 15 to 24. METHODS: In 1998 we administered a cross-sectional survey to all the first-year medical students at the National Autonomous University of Mexico, which is the largest university in Latin America. For this study we analyzed 549 surveys completed by female students. RESULTS: Out of the 549 women, 120 of them (22 percent) had been sexually active at some point. Among those 120 sexually active students, 100 of them (83 percent) had used a contraceptive method at some time, and 19 of the 120 (16 percent) had been pregnant. Of those 19 women who had been pregnant, 10 of them had had an illegal induced abortion (in Mexico, abortions are illegal except under a small number of extenuating circumstances). The reported abortion rate among the female medical students, 2 percent, was very low in comparison with the 11 percent rate for women of similar ages in the Mexican general population. CONCLUSIONS: The lower incidence of abortion among the female medical students indicates that when young Mexican women have access to medical information and are highly motivated to avoid unintended pregnancy and abortion, they can do so.

Implicaciones sociales de la calidad profesional de los médicos y de la certificación / Social implications of the professional quality of physicians and of medical licensure

Se analizan las aplicaciones sociales de la calidad profesional de los médicos y del proceso certificador. La adecuada competencia de los médicos reviste gran importancia en los países caracterizados por amplias diferencias socioeconómicas. Esta diversidad de condiciones, demanda médicos capaces para confrontarse con una variedad de ambientes y lograr la mejor práctica profesional con uso óptimo de los recursos para la atención a la salud. La competencia y la calidad de la atención están articuladas. El acoplamiento entre el conocimiento universal y las condiciones locales crea una diversidad sincrónica de prácticas profesionales. De igual forma, la certificación de los médicos debe ser vista como parte del proceso difusor de las innovaciones. Asimismo, la existencia de capacidades diferenciales para contender con el cambio, contribuye a crear una diversidad diacrónica de prácticas médicas. A la luz del proceso de mejora continua de la calidad, los sistemas de certificación requieren articularse tanto con la educación médica continua, como con el proceso de acreditación de las instituciones de salud. De lo contrario, se corre el riesgo de aumentar la falta de equidad en la práctica médica y terminar culpando a la víctima.

Infecciones por Escherichia coli enteropatógena / Infectious diseases by Enteropathogenic Escherichia coli

Escherichia coli es una bacteria reconocida como uno de los principales agentes causantes de diarrea en humanos. Las diferentes capas de esta bacteria en humanos se clasifican en 5 categorías diferentes: enterotoxigénica (ETEC), enteroinvasiva (EIEC), enterohemorrágica (EHEC), enteroagregativa (EAggEC) y enteropatógena (EPEC). Las cepas del grupo EPEC son responsables de diarrea en niños menores, principalmente de países en desarrollo. El propósito de esta revisión consiste en presentar los conocimientos más recistentes relacionados con la patogénesis del grupo EPEC, así como las contribuciones de investigadores mexicanos en el conocimiento del microorganismo.

Enfermedades diarreicas y nutrición / Diarrheic deseases and nutrition

La diarrea se define como la evacuación de heces líquidas y el aumento de peso de las evacuaciones diarias (frecuencia y volumen), con disminución en la consistencia y sensación de urgencia, malestar perianal o incontinencia. La diarrea aguda tiene una duración inferior a los 13 días, mientras que la persistente 14 días o más. La presencia de leucocitos en las heces define a la diarrea como inflamatoria. Por su fisiología se clasifican en: OSMOTICAS, SECRETORAS, SECUNDARIAS A TRASTORNOS DE LA MOTILIDAD INTESTINAL y causadas por ALTERACIONES MORFOLOGICAS DE LA MUCUOSA. Las causas principales son: amibiasis, shigelosis, salmonelosis, otras infecciones intestinales (VIBRIO CHOLERAE, CAMPYLOBACTER, rotavirus) e intoxicaciones alimentarias. Apartados del trabajo: 1) Estructuras involucradas en la absorción. 2) Fisiología de la absorción intestinal del agua, los electrólitos y la glucosa. 3) Definición y clasificación de la diarrea. 4) Aspectos epidemiológicos de las diarreas infecciosas. 5) Riesgos de enfermedad diarreica por causas infecciosas. 6) Secuelas de las gastroenteritis infecciosas. 7) Evaluación del paciente con diarrea. 8) Bases fisiológicas del tratamiento de la diarrea. 9) Tratamiento de la diarrea. 10) Alimentación durante el episodio diarreico. 11) Uso de antibióticos en el tratamiento de las diarreas. 12) Rehabilitación. 13) Prevención de la enfermedad diarreica de origen infeccioso

Vacunas contra Escherichia coli causante de diarrea en humanos / Vaccines against scherichia coli causing of diarrhea in humans

En este capítulo se describen las interacciones entre diferentes tipos de cepas de Escherichia coli con las células del epitelio intestinal, lo cual lleva a que el hospedero presente diarrea. El conocimiento de estas interacciones, emanado de veinte años de investigación, han permitido en fechas recientes plantear el uso de vacunas como medida de control de la enfermedad diarreica. La asociación constante entre los serotipos E. coli con procesos diarreicos, ha permitido plantear medidas de control a través de la búsqueda de los mecanismos comunes de patogenicidad que comparten la mayoría de los serotipos de E. coli. Estos mecanismos corresponden fundamentalmente a tres tipos: 1) adhesivos, que permiten a las bacterias acercarse, pegarse y colonizar el epitelio de ciertas áreas del intestino; 2) producción de proteínas bacterianas (toxinas) que estimulan la secreción de agua y electrolitos al interactuar con mecanismos bioquímicos de las células del huésped y 3) invasión y reproducción dentro del citoplasma de células epiteliales del intestino para evadir los mecanismos de protección del hospedero

Haemophilus influenzae b: una revisión sobre los determinantes de patogenicidad y de la respuesta inmune a la infección / Haemophilus influenzae b: a review of the determinants of the pathogenicity and immune response

Hemophilus influenzae continuá siendo en nuestro país un patógeno importante en gran variedad de procesos infecciosos que se presentan principalmente en la edad pediátrica. Los datos epidemiológicos señalan al sistema nervioso central (SNC) y a las vías respiratorias altas y bajas como los sitios más afectados. Para que se manifieste la enfermedad infecciosa por este organismo deben participar diversos factores, tanto el hospedero como del propio parásito. Dentro de estos factores, se encuentran los determinantes de patogenicidad del parásito y los de resistencia del hospedero. La interación de determinantes superficiales, subcelulares y/o productos extracelulares de este organismo patógeno y los mecanismos de resistencia del hospedero, conducen o no al establecimiento de enfermedad. El conocimiento y análisis de los determinantes de patogenicidad del parásito y de los factores de respuesta inmune del hospedero, permitirán identificar componentes útiles para el diagnóstico de la enfermedad, para señalar componentes bacterianos como candidatos importantes para la prevensión del padecimiento y para implementar estrategias adecuadas de tratamiento antimicrobiano apropiado

Haemophilus influenzae is still one of the main causes of diverse invasive diseases in children in México. Epidemiologic data indicate that these processes affect primarily the central nervous system and the respiratory tract. Several factors are involved in the expression of infectious disease by this organism, among them the pathogenic determinants of the parasite and those related with resistance in the host. Ocurrence of disease is usually the result of the interaction between these determinants. Knowledge of these pathogenic determinants of the parasite and of factors involved in the immune response of the host have allowed an understanding of the infectious process and have directed research in a least three areas: 1) identification of bacterial membrane fractions related with diagnosis of the disease, 2) screening for immunogenic components in the bacterias as vaccine candidates to be used in the prevention of the disease and, 3) the planning of appropriate alternatives for specific antimicrobial therapy.