[Hygienic profile of the water in Milan swimming pools: a three-year comparative study]. / Profilo igienico-sanitario dell'acqua delle piscine milanesi: tre anni a confronto.

The aim of this work was to determine whether swimming pool water quality in Milan from 2006 to 2008 was within the standards established by national and local Italian laws (Circolare Min. Sanità 128/71 and DGR 2552/2006). In 2006, 580 samples of water from public swimming pools were analyzed to determine the presence of heterotrophic counts at 37 degrees and total coliforms; pH, free chlorine and chloride of each sample were also measured. In the following years, water from both public and private swimming pools were examined to measure heterotrophic count at 22 degrees and 36 degrees, Escherichia coli, enterococci, Pseudomonas aeruginosa, Staphylococcus aureus, pH, free chlorine, and nitrates. The total number of analyses carried out in 2007 and 2008 was 2074 and 1532, respectively. In 2006, the extent of noncompliance of all swimming pools that was observed for both physical/chemical and microbiological parameters was 72.3%, which then decreased to 53.2% and 36.2% in 2007 and 2008, respectively. In particular with regard to the microbiological analysis, an increase of noncompliance based on at least one parameter was determined (7.1% in 2006 vs. 21.5% in 2007 and 22% in 2008). In contrast, a decrease of the extent of noncompliance based on at least one physical/chemical parameter was observed (from 68.1% in 2006 to 40.4% and 22.3% in 2007 and 2008, respectively). Interestingly, public swimming pools exceeded the legal limits of microbiological concentration more often than the private ones, whereas both types of swimming pools showed a decrease in noncompliance with regard to the physical/chemical parameters.

[Investigation on strains of Legionella pneumophila, isolated from a hospital of Milano, with three genotyping methods]. / Genotipizzazione di ceppi di Legionella pneumophila, isolati in strutture sanitarie di differenti tipologie.

Various techniques have been developed in recent years for the molecular typing of microorganisms. Remains particularly difficult to isolate clinical strains for the low availability of cases and even more problematic matching clinical / environmental strains. We investigated 13 strains of Legionella pneumophila of clinical and environmental origin, isolated in 3 Health Facilities in Milan (2003-2006), using three molecular typing methods: Pulse-Field Gel Electrophoresis, Amplified Fragment Length Polymorphism and Sequence-Based Typing. PFGE and AFLP showed the correlation between a clinical case with only one of the environmental isolates taken from the places frequented by the patient, demonstrating with certainty the nosocomial origin of the case and identifying the source of infection in the shower water (Clin. 1 and Env. 1N). Two clinical samples from patients admitted to different wards presented an identical profile, which suggests that the nosocomial origin assumed an epidemic form, even without having isolated the environmental strain due to the absence of samples drawn during the period under consideration (Clin. 2 and 3). Finally, the comparison between the isolated environmental strains demonstrated a heterogeneous presence of strains, not correlated to each other although they belong to the same serum-group, having profiles that are clearly different regarding number and position of bands (Env. 2 and 4). The profile 2,10,18,10,1,1 had never been isolated and typed previously in Europe. The SBT has proved a better technique for reproducibility and interpretation of results than PFGE and AFLP To complete studies on SBT method, now considered gold standard, is currently being the EWGLI 5th Proficiency Panel, in which we are actively involved with the genotyping of five strains according to the latest version of the protocol (4.1).

[5-year surveillance for Legionella pneumophila and comparison of disinfection methods in two hospitals of Milan]. / Sorveglianza ambientale di Legionella pneumophila e meto- di di bonifica a confronto in strutture sanitarie di Milano (risultati di un quinquennio).

We performed an environmental monitoring in an hospital to estimate the level of contamination from Legionella spp., in connection with several treatments of reclamation. In period 2002-2006 we executed 238 samplings in 21 units hospitals (from hot water, biofilm, filter of the conditioning system, instrument for the assisted respiration) for the detection of Legionella spp. The contaminated points have been subordinates to reclamation (hyperchlorination, maintenance of boilers/tanks, taps' and showers' substitution, increased temperature, elimination of dead points of the system and chlorine dioxide) and subsequently we sampled to verify the efficiency of the disinfection. Environmental investigation found 58% of the cases positive for Legionella spp. (139/238), with maximum count in order of the 10(4) UFC/L, demonstrating colonization of Legionella pneumophila (132/139, 70% Serogroup 2-14, 19% Serogroup 1, 11% both). The used treatments were effective, in different ways, in the short period, but not in the medium-term, because progressive recolonization happened approximately after a month; only the use of chlorine dioxide brought to counts less than 100 UFC/L until now. Chlorine dioxide seems to maintain a mainly protecting effect, however this effectiveness will have to be demonstrated also for longer periods.

Evaluation of Milan University Dental Students' knowledge of health and hygiene risks related to clinical work.

AIM: Several different subjects in the Degree Course in Dentistry and Prosthodontics, including Hygiene, are of fundamental importance to understand and prevent hygiene/ health risks in the dental field. The aim of this investigation is to evaluate the knowledge acquired by students during the Degree Course in Dentistry. METHODS: A questionnaire was distributed to 121 students of the Degree Course in Dentistry and Prosthodontics at Milan University; the questionnaire, drawn up by the Working Group SItI ''Hygiene in Dentistry'' was structured in 3 parts: personal data; transmission of infectious diseases in dentistry; measures to control and prevent cross-infection. RESULTS: The students were all aware of the health/hygiene risks in dentistry; they knew the principal transmissible infectious diseases (while confusing actual risk of transmission with disease's fears) and the procedures at highest risk of cross-infection for patients and dental professionals; they correctly determined the highest-risk categories of patients and the individual protection devices to be used in dental practice. However, they knew little about their own vaccination status; a low percentage of students answered correctly on which environmental matrices can be contaminated or the more technical questions on disinfection and sterilisation procedures for the instruments employed. CONCLUSIONS: The students' replies show they possess a fair theoretical knowledge of transmission risks; however, some gaps exist above all in the practical application of this knowledge, and it appears clear that these should be addressed in detail, possibly with the help of a specific tutor providing support during normal clinical work in the last year of the course.

[Quality of some working places in Milan]. / Indagine conoscitiva della qualità di ambienti di lavoro nella città di Milano.

Questionnaires were distributed to the responsibles and to the dependents of structures with high turnover of people, to have informations about numbers and typology of instruments, habits of dependents and type of cleanings. In these structures, microbiologic quality of air and of informatic instruments' surfaces were evaluated and efficacy of treatment with some products of cleaning and sanification was verified. Air microbiological contamination was comparable to that found in other similar researchs. Fecal contamination indicators were not found on instruments' surfaces, both before, and after treatment; in 8 cases (3%) Staphylococcus aureus was isolated and in 6 cases (2%) species of not pathogenous staphylococci were isolated. At the beginning of the working day, mean values of total aerobic bacterial count at 22 degrees and 37 degrees, were low, settled to zero after treatment and increased progressively during the week. Infective risk for workers can be considered insignificant because of low microbiological contamination. Specific sanification products seem not to be necessary, since common products of cleaning have the same efficacy.

[Dental offices and environment quality]. / Ambulatorio odontoiatrico e qualità ambientale.

AIM: The aim of this study was to survey, from a microbiological point of view, dental unit water, air and surface quality in public dental offices and in control environments in Milan. METHODS: We studied tap and dental unit water (from fountain, air-water syringe, turbine), at the beginning and at the end of monday and thursday morning activity; air quality with surface air system (SAS) in dental and control offices; handpieces holder, fountain block, arm of the light, dental trolley, inner and outer walls surfaces quality. RESULTS: Water from the dental unit waterline shows average exceeding the law limits 2-3 fold for total bacteriological counts at 37 degrees and 22 degrees, in all examined points, at the beginning of the working day. There is an improvement in the water contamination at the end of the activity. Pseudomonas aeruginosa is frequently found, total and fecal coliforms are absent, while Legionella pneumophila was found only in one control. Air and surfaces quality is quite good, especially in places with ventilation systems in function. CONCLUSION: Dental unit water is the most critical point among those monitored. Water quality has to be improved with specific projects.

[Hygiene-sanitary risks associated with dentistry in the city of Milan. Questionnaire-based survey]. / Rischi igienico-sanitari legati all'assistenza odontoiatrica, nella città di Milano. Indagine questionaria.

BACKGROUND: Aim of this investigation is to identify possible sanitary risks connected with the practice of dentistry and to draw up guidelines which may help all those who work in this field. METHODS: Between April and July 1998, we distributed 231 questionnaires to public and private dental offices in Milan, to evaluate dentists' knowledge of sanitary risks in their practices. One hundred and sixteen of the 231 distributed questionnaires were returned. All the dentists contacted, used protective measures such as gloves, masks, glasses, and high-speed aspirators. RESULTS: Survey responses indicated that the most readily transmittable infectious diseases in dentist's practices are, in order of importance, hepatitis, AIDS, airborne diseases, and herpes. Surgery, endodontics, and the use of sharp instruments most likely lead to transmission of pathogens in both patients and dentists. Dentist's knowledge of out-patient treatment is good whereas their knowledge of the use of disinfectants for dental equipment is poor. CONCLUSIONS: The latter suggests the utility of continuing education in this critical aspect of the practice of dentistry.

[Experience with anti-hepatitis-B vaccination using a recombinant DNA vaccine, in students of dentistry at the University of Perugia]. / Esperienza di vaccinazione anti-epatite B, con vaccino a DNA ricombinante, negli studenti di odontoiatria dell'Università di Perugia.

Infection with HBV is still one of the more important professional risk for medical staff. This is particularly true for dentists the more so when they are operating in areas at medium or high prevalence of HBsAg carriers. In such situation patients often ignore their carrier state, when they know it they are not always conscious of the importance of notifying the information to their dentist. The dentists, on the other hand, don't routinely collect a detailed anamnesis of their patients. For these reasons the opportunity of being vaccinated against hepatitis B with a DNA recombinant vaccine was offered to dentistry students of the University of Perugia. All participants were to be negative for hepatitis B markers of infection including HBsAg and anti HBs. All volunteers were to have normal aminotransferase levels, be in good physical condition and give their informed written consent. 48 students turned out to be eligible for vaccination, of them 35 were males, 13 females, mean age 23 years. About two months after the third dose, all the vaccinees had seroconverted and 70.4% of them showed antibody titres between 1,000 greater than or equal to 10,000 UI/l. That indicate that very likely the antibody persistence will be long lasting (at least 5 years). Side effects, light and of short duration, were rarely seen.

[Epidemiologic situation of rubella in Italy 20 years after the introduction of the vaccine]. / Indagine sulla situazione epidemiologica della rosolia in Italia a distanza di circa vent'anni dall'introduzione della vaccinazione.

Rubella vaccination has been introduced in USA in 1969: it was addressed to all the newborn and to women in childbearing age. In 1970 it was offered in Europe to schoolgirls aged 11-14 and to women of reproductive age. The purposes were identical--namely to eliminate the incidence of CRS--in spite of the different strategies adopted: in fact the American vaccination programme tried to reach this aim in eradicating the disease, while in Europe special attention was given to the possibility of reduce morbidity in childbearing age. After 20 years we can try to verify if these objects have been attained. Recent data (MMWR, 1987) show that rubella morbidity in USA has dropped considerably (incidence rate in 1966 = 24.3; in 1986 = 0.2) and incidence rate for CRS decreased accordingly from 0.90 (1969) to 0.32. Nevertheless we must underline that 47.5% of cases in USA from 1984 to 1986 were seen in person older than 20, and serologic studies have shown that infection susceptibility, in the postpuberal population, is the same that in prevaccinal era (10-20%). Many evaluation of efficacy of vaccinal strategies have been carried out in Europe, always showing a smaller number of women of reproductive age susceptible toward infection, together with a reduced probability of exposure during pregnancy. In European countries, were rubella vaccination has been offered only to women, morbidity has not changed appreciably. In Italy rubella vaccination has not been introduced at the same time and with the same extension in all regions: for this reason it is not possible to evaluate efficacy of this vaccination policy on a whole. Considering ISTAT data from 1971 to 1987 we can identify epidemic outbreaks in 1973, 1978, 1982 (of limited intensity) and 1984; practically every six years, as they took place before vaccination era; if we take into account case notified between 1971 and 1981 in the different age groups (table 1) we can see that the higher prevalence is always in the 6-13 years age group. Vaccination has not modified the epidemiologic trend of the disease. However, considering only the class toward whom vaccination was addressed from the beginning, that is women of reproductive age, that can have had the possibility to be vaccinated in prepuberal years at school or in another occasion, after serologic screening, in adult life, we can notice substantial differences in infection susceptibility in comparison with prevaccinal era, that was about 10-20% (Galli, 1982).(ABSTRACT TRUNCATED AT 400 WORDS)

[Anti-hepatitis B vaccination in health personnel at the Ospedale Maggiore of Milan]. / Vaccinazione anti-epatite B nel personale sanitario dell'Ospedale Maggiore di Milano.

The paper deals with the screening of the staff at the Ospedale Magiore of Milan within the Region-wide program of recommended B Hepatitis vaccination. The HBsAg positive subjects are 3.1% and antiHBs are 32.7%; the susceptibility of the infection decreases with age and working seniority; infection markers are found most frequently in subjects working in the Dialysis Ward. The health staff informed about the professional risk of infection is still reluctant for this immunization; in fact only 62.5% of susceptible accepted the vaccine. Seroconversion was observed in 89.8%; collateral reactions to vaccine were of minor importance and short duration.

[Antipneumococcal vaccination: comparison between vaccines]. / Vaccinazione antipneumococcica: confronto fra vaccini.

Fourteen antigen and 17 antigen polyvalent vaccines against Str. pneumoniae have been tested on 137 healthy volunteers. They have been shown to cause side-effects infrequently. A two-fold or higher increase of antibody concentration (detected by RIA) has been demonstrated in 80% of the vaccinees against all antigens of the 17 valent vaccine; while such increase has been demonstrated only for 12 out of 14 antigens in the other vaccine (for the other two antigens the percentages have been 66.7% (antigen 1) and 73.7% (antigen 12F). It is stressed that the use of these vaccines is particularly recommended for the prevention of pneumococcal diseases in higher risk subjects.