[Domestic exposure to moulds and mite allergens in Parisian patients]. / Exposition domestique aux moisissures et aux allergènes d'acariens de patients parisiens.

INTRODUCTION: Moulds and mite allergens present in indoor environments are well known for their effects on respiratory health. METHODS: From 2011 to 2015, the Paris Service for Environmental Health (SPSE) conducted investigations in 293 dwellings following medical referral. These audits included fungal analysis of air (in 12% of dwellings), in mattress surface and floor dust (24%), and mite allergen quantifications in mattresses and carpets (18%). RESULTS: Indoor air fungal concentrations are not significantly different from those in outdoor air. When there is no ventilation or when the system is malfunctioning, an increase in indoor/outdoor air ratios is observed, indicating mould enrichment in the dwelling's indoor air. With regard to house dust samples, fungal spore concentrations vary according to the media from which samples were collected. Mattress fungal contamination is higher in dwellings where observed surface moulds exceed 1 per square meter. In the same way Der p1 mite allergens levels are greater in mattress dust in dwellings where mould contamination is visible. CONCLUSIONS: This study describes the levels of contamination in the dwellings of Parisian patients.

Diversity, community composition, and dynamics of nonpigmented and late-pigmenting rapidly growing mycobacteria in an urban tap water production and distribution system.

Nonpigmented and late-pigmenting rapidly growing mycobacteria (RGM) have been reported to commonly colonize water production and distribution systems. However, there is little information about the nature and distribution of RGM species within the different parts of such complex networks or about their clustering into specific RGM species communities. We conducted a large-scale survey between 2007 and 2009 in the Parisian urban tap water production and distribution system. We analyzed 1,418 water samples from 36 sites, covering all production units, water storage tanks, and distribution units; RGM isolates were identified by using rpoB gene sequencing. We detected 18 RGM species and putative new species, with most isolates being Mycobacterium chelonae and Mycobacterium llatzerense. Using hierarchical clustering and principal-component analysis, we found that RGM were organized into various communities correlating with water origin (groundwater or surface water) and location within the distribution network. Water treatment plants were more specifically associated with species of the Mycobacterium septicum group. On average, M. chelonae dominated network sites fed by surface water, and M. llatzerense dominated those fed by groundwater. Overall, the M. chelonae prevalence index increased along the distribution network and was associated with a correlative decrease in the prevalence index of M. llatzerense, suggesting competitive or niche exclusion between these two dominant species. Our data describe the great diversity and complexity of RGM species living in the interconnected environments that constitute the water production and distribution system of a large city and highlight the prevalence index of the potentially pathogenic species M. chelonae in the distribution network.

Surveillance of enteroviruses in France, 2000-2004.

In the context of poliomyelitis eradication, a reinforced sentinel laboratory network for surveillance of enteroviruses (RSE) was implemented in France in January 2000, and the purpose of this report is to describe the results of the five first years of surveillance. From 2000 to 2004, the RSE laboratory network performed detailed surveillance of the circulating enteroviruses. No wild-type poliovirus was isolated from humans during the 5 years of surveillance, although two imported vaccine polioviruses were detected. During the same period, Sabin-like polioviruses were identified on five occasions in the sludge from sewage treatment plants, but no wild-type poliovirus was found. Over the 5 years of surveillance, information was collected from 192,598 clinical samples, including 39,276 cerebrospinal fluid specimens, of which 14.7% were positive for enteroviruses, 45,889 stool samples (4.3% positive for enteroviruses), 70,330 throat swabs (2.2% positive) and 14,243 sera (1.4% positive). The ten main nonpolio enteroviruses typed were as follows, in decreasing order of frequency: E-30, E-13, E-6, CV-B5, E-11, CV-B4, E-9, E-7, CV-B1, and CV-B2. During the year 2000, an outbreak of aseptic meningitis due to three main enteroviruses (echoviruses type 30, 13, and 6) was monitored. Continued surveillance of enteroviruses is important to alert physicians and public health officials to changes in disease trends. Although the geographical coverage of the RSE network as well as the percentage of enteroviruses identified must be improved, the large number of samples tested for enteroviruses shows the ability of virology laboratories to detect the circulation of enteroviruses and to report the possible identification of poliovirus (wild-type, vaccine-derived, or Sabin-like).

Detection of Microsporidia, cryptosporidia and Giardia in swimming pools: a one-year prospective study.

In order to estimate the rate of microsporidia, cryptosporidia and giardia contamination of swimming pools, sequential samples of water were collected during a one-year period in six different swimming pools in Paris, France. Fourty-eight samples were submitted to filtrations. Eluates were examined for microsporidia using polymerase chain reaction (PCR) and for cryptosporidia and giardia using immunofluorescence staining. One of 48 specimens was positive for microsporidia. Using DNA sequence analysis, unknown microsporidia species were identified, which were close to an insect microsporidia Endoreticulatus schubergi. One sample was positive for cryptosporidia and none were positive for giardia. This study shows a low level of swimming pool water contamination by microsporidia, cryptosporidia or giardia, demonstrating the efficacy of cleaning filtration and disinfection procedures used in French swimming pools.

Single clonal origin of a high proportion of Legionella pneumophila serogroup 1 isolates from patients and the environment in the area of Paris, France, over a 10-year period.

Arbitrarily primed PCR with three primers and pulsed-field gel electrophoresis were used to characterize a set of 75 clinical Legionella pneumophila serogroup 1 isolates, with no apparent epidemiological link, obtained from 24 hospitals in Paris, France, from 1987 to 1997. Unexpectedly, 25 clinical isolates from 15 hospitals had an identical profile (termed type A) by both methods. The same profile was subsequently found in 16 of 64 randomly selected environmental L. pneumophila serogroup 1 isolates from 15 different sites in the Paris area. There was no evidence of geographic clustering or a peak incidence of type A isolation. Type A has not been found in France outside the Paris area, suggesting that a particular type of L. pneumophila serogroup 1 is specifically present in the Paris water distribution network.

Epidemic cluster of legionnaires disease in Paris, June 1998.

From 29 June to July 1998, four cases of legionnaires disease in British citizens were reported to the Reseau National de Sante Publique (RNSP) by the statutory notification system (declaration obligatoire (DO)) and by theEuropean Surveillance Scheme for

Detection of naturally occurring enteroviruses in waters by reverse transcription, polymerase chain reaction, and hybridization.

Comparison in virus-seeded mineral water of three detection methods for enteroviruses, direct hybridization, cell culture, and reverse transcription into cDNA followed by polymerase chain reaction and hybridization, showed that the last procedure was 10 to 1,000 times more sensitive than detection by cell culture and 10(5) to 10(7) times more sensitive than direct hybridization. The presence of naturally occurring enteroviruses was also demonstrated in activated sludge and in concentrated and non-concentrated surface water samples by reverse transcription-polymerase chain reaction-hybridization. However, in activated sludge and in concentrated surface waters, enzymatic amplification was sometimes inhibited by contaminants.

The intracellular multiplication of Legionella pneumophila in protozoa from hospital plumbing systems.

Between October 1987 and March 1989, we tested 144 water samples obtained from the plumbing and cooling tower systems of 5 Paris hospitals for the presence of legionellae and amoebae. Of the samples tested for Legionella, 67 out of 144 (46.5%) were positive, and 82 out of 116 tested for amoebae (70.7%) were positive. The ability of protozoa to support the multiplication of legionella was shown by incubating samples at 35.5 degrees C for 7-15 days. Prior to determining the presence of legionellae and amoebae, 51 of the 144 samples were incubated. After incubation, 22 out of 25 (88%) samples which were positive for the presence of both Legionella and amoebae showed multiplication of Legionella. In 3 out of the 25 (12%) samples containing Legionella and amoebae, Legionella failed to multiply. Six out of the 51 (11.8%) samples which were negative in direct culture for Legionella but positive for amoebae, became positive after incubation. Legionella did not multiply in samples negative for amoebae, nor was there proliferation in samples after filtration through a 1.2-microns membrane followed by incubation for the same period and temperature. Strains of Legionella pneumophila serogroup 1 and serogroup 6 (SG1 and SG6), including 3 patient isolates and 2 environmental isolates, were cocultured with 2 strains of amoebae and Tetrahymena pyriformis. Plate counts, Gimenez staining and electron microscopy demonstrated that intracellular legionellae proliferation occurred.