Epidemiology and clinical features of gastroenteritis in hospitalised children: prospective survey during a 2-year period in a Parisian hospital, France.

Rotavirus is recognised as the most important agent of severe acute gastroenteritis (AGE) in young children. In a 2-year prospective survey, we investigated the epidemiology and clinical features of the viral and bacterial pathogens in children hospitalised for AGE. The study was performed in a Parisian teaching hospital from November 2001 to May 2004. Clinical data were prospectively collected to assess the gastroenteritis severity (20-point Vesikari severity score, the need for intravenous rehydration, duration of hospitalisation). Stools were systematically tested for group A rotavirus, norovirus, astrovirus and adenovirus 40/41, sapovirus and Aichi virus and enteropathogenic bacteria. A total of 457 children (mean age 15.9 months) were enrolled. Viruses were detected in 305 cases (66.7%) and bacteria in 31 cases (6.8%). Rotaviruses were the most frequent pathogen (48.8%), followed by noroviruses (8.3%) and adenoviruses, astroviruses, Aichi viruses and sapoviruses in 3.5%, 1.5%, 0.9% and 0.4%, respectively. Cases of rotavirus gastroenteritis were significantly more severe than those of norovirus with respect to the Vesikari score, duration of hospitalisation and the need for intravenous rehydration. Rotaviruses were the most frequent and most severe cause in children hospitalised for AGE, and noroviruses also account for a large number of cases in this population.

Unexpected substitution of dominant rotavirus G genotypes in French hospitalized children over five consecutive seasons.

The study was designed to evaluate the circulation of group A rotaviruses in French hospitalized children, and to detect unusual strains. This prospective study was conducted from 2001 to 2006 in children consulting for acute diarrhea at the pediatric emergency department in three French University Hospitals. The rotaviruses were detected by rapid test and genotyped by RT-PCR on the basis of their outer capsid proteins VP4 (P-type) and VP7 (G-type). The stools from 757 children were analyzed. G1P[8] strains were predominant (44.0%), followed by G9P[8] (17.7%), G3P[8] 13.1%, G4P[8] (9.5%), and G2P[4] (1.8%); mixed rotavirus infections occurred in 2.3%. G9 rotaviruses emerged during the 2004-2005 season (73.4%) and remained the second most prevalent strains. Few unusual strains, G6, G8, G12 and P[6]-types, were detected. The monitoring of rotavirus infections should be maintained to document strain distribution and to assess the emergence of new reassortants that may not respond to current rotavirus vaccines.

[Systematic family screening in case of infant pertussis]. / Dépistage familial systématique dans la coqueluche du nourrisson.

The origin of contamination in pertussis of young infants is generally the close relatives. From 2000 to 2004, only serology and culture were available in our hospital. The families of 16 young infants (age below one year) hospitalized for pertussis were screened using serological tests: 21/48 contacts were positive. After 2004, PCR was available for exploration of index cases and families: 35/85 contacts were positive. Of the mothers tested 23/46 were positive compared to 14/41 fathers. Only one parent presented with a typical paroxystic pertussis cough, 60% presented with a nonparoxystic cough having lasted for more than five days and 40% of positive adults did not present with cough. Despite official recommendations, none of these young parents had received an antipertussis booster vaccination. This study shows the high frequency of atypical or nonsymptomatic pertussis in adults in the close family of infected young infants. These adults contribute to spreading the disease.

[Simultaneous outbreaks of rotavirus and respiratory syncytial virus in Paris: a 12-year survey]. / Coïncidence des épidémies de rotavirus et de virus respiratoire syncytial à Paris: 12 ans de surveillance.

OBJECTIVE: The authors had for aim to study the coincidence of RSV and rotavirus epidemic peaks in pediatric patients hospitalized in the Paris area. METHODOLOGY: A retrospective hospital-based monocentric cohort study was made over a 12-year period (1993-2004). Clinical and laboratory findings were prospectively collected on admission. RESULTS: Three thousand and four hundred ninety-six stool samples were positive for rotavirus; 3,507 nasopharyngeal aspirates were positive for RSV. The coincidence of epidemic peaks for both viruses in November, December, and January was observed during the 12 years of the study. CONCLUSION: The exact coincidence of winter outbreaks of RSV and rotavirus is a characteristic of the Paris area. It contributes to increase overcrowding in pediatric units and nosocomial infections.

Pertussis in young infants: apnoea and intra-familial infection.

This study investigated 41 infants, aged <4 months, who were hospitalised with symptoms compatible with pertussis. Of these, 16 had Bordetella pertussis infection confirmed by real-time PCR. For four of these 16 patients, the initial sample was PCR-negative, but samples collected 5-7 days after the onset of infection were PCR-positive. PCR was also positive with samples from 15/16 families and 20/41 household contacts. Nine of the 20 positive household contacts were asymptomatic. Among the 16 infants with proven pertussis, apnoea was more frequent than in a control group for whom PCR was negative with both children and household contacts (69% vs. 28%). It was concluded that real-time PCR performed with samples from household contacts facilitates the diagnosis of infants suspected clinically of having pertussis, thereby enabling earlier treatment.