Vaccines for viral and bacterial pathogens causing acute gastroenteritis: Part I: Overview, vaccines for enteric viruses and Vibrio cholerae.

Efforts to develop vaccines for prevention of acute diarrhea have been going on for more than 40 y with partial success. The myriad of pathogens, more than 20, that have been identified as a cause of acute diarrhea throughout the years pose a significant challenge for selecting and further developing the most relevant vaccine candidates. Based on pathogen distribution as identified in epidemiological studies performed mostly in low-resource countries, rotavirus, Cryptosporidium, Shigella, diarrheogenic E. coli and V. cholerae are predominant, and thus the main targets for vaccine development and implementation. Vaccination against norovirus is most relevant in middle/high-income countries and possibly in resource-deprived countries, pending a more precise characterization of disease impact. Only a few licensed vaccines are currently available, of which rotavirus vaccines have been the most outstanding in demonstrating a significant impact in a short time period. This is a comprehensive review, divided into 2 articles, of nearly 50 vaccine candidates against the most relevant viral and bacterial pathogens that cause acute gastroenteritis. In order to facilitate reading, sections for each pathogen are organized as follows: i) a discussion of the main epidemiological and pathogenic features; and ii) a discussion of vaccines based on their stage of development, moving from current licensed vaccines to vaccines in advanced stage of development (in phase IIb or III trials) to vaccines in early stages of clinical development (in phase I/II) or preclinical development in animal models. In this first article we discuss rotavirus, norovirus and Vibrio cholerae. In the following article we will discuss Shigella, Salmonella (non-typhoidal), diarrheogenic E. coli (enterotoxigenic and enterohemorragic), and Campylobacter jejuni.

Vaccines for viral and bacterial pathogens causing acute gastroenteritis: Part II: Vaccines for Shigella, Salmonella, enterotoxigenic E. coli (ETEC) enterohemorragic E. coli (EHEC) and Campylobacter jejuni.

In Part II we discuss the following bacterial pathogens: Shigella, Salmonella (non-typhoidal), diarrheogenic E. coli (enterotoxigenic and enterohemorragic) and Campylobacter jejuni. In contrast to the enteric viruses and Vibrio cholerae discussed in Part I of this series, for the bacterial pathogens described here there is only one licensed vaccine, developed primarily for Vibrio cholerae and which provides moderate protection against enterotoxigenic E. coli (ETEC) (Dukoral(®)), as well as a few additional candidates in advanced stages of development for ETEC and one candidate for Shigella spp. Numerous vaccine candidates in earlier stages of development are discussed.

[Clinical and epidemiological profile of intestinal intussusception among infants of Metropolitan Santiago]. / Perfil epidemiológico y clínico de la invaginación intestinal en lactantes de la Región Metropolitana.

BACKGROUND: Intussusception (IS) is a potentially severe disease that affects an undetermined number of Chilean infants. The withdrawal of a rotavirus vaccine in 1999 due to its association with IS, highlighted the need for updated information on IS worldwide including Chile, before introduction of new vaccines. AIM: To estimate the incidence and to describe the epidemiology and clinical presentation of IS in the Metropolitan Area of Chile. MATERIAL AND METHODS: IS cases occurring between 1996 and 2001 in the seven public pediatric hospitals and in six private clinics (during 2000 and 2001) were identified. Incidence rates were calculated using updated population estimates. A systematic review of the medical charts of IS cases occurring in the public hospitals for 2000-2001 was performed. RESULTS: IS incidence rates for the Public Sector ranged from 32 to 39 per 100,000 children < 2 years of age. These figures did not vary significantly among the different Health Care Services, nor after inclusion of the private clinics. IS was more common in males (66%) and infants younger than 12 months (83%), with 67% of cases occurring between 3 and 8 months of age. The most common presenting symptoms were abdominal pain (90%), vomiting (86%), and rectal bleeding (75%). Ileocolic IS predominated (83%) and surgical correction was the preferred treatment (81%). No death occurred in this series. CONCLUSIONS: IS incidence rates were intermediate compared to other series, stable over time, and similar between the public and private sector. Clinical characteristics were similar to those previously reported with a disproportionately high use of surgical correction over enema, currently considered the preferred treatment option.