Development of an innovative method for the evaluation of fungal contamination of surfaces.

The objective of this technical report is to compare the ability to capture fungal spores through samples performed with three different methods: Rodac contact plates, cotton pad and a pad prepared with a dusting cloth (DC pads) selected from those available on the market. The tests were conducted using a suspension of Aspergillus niger conidia equal to 0.5 MacFarland diluted 1/30, 1/40, 1/50, 1/100. With each of these dilutions 3 sterile tiles of stainless steel were contaminated, each divided into 16 small squares, in the center of which 0.1 ml of the dilution chosen was placed and left to dry (for a total of 12 sheets). In addition, we have used other 6 tiles to repeat the experience with dilutions 1/40 and 1/50. A total of 288 squared surfaces were contaminated: 96 of these were sampled with Rodac contact plates, 96 with cotton pads and 96 with DC and then inseminated in Petri plates. Sabouraud dextrose agar was used as culture medium for the first 12 plates, while, for the other 6 plates Sabouraud dextrose agar added with lecithin and polysorbate 80 was used. All plates were incubated at 37 degrees for 18 hours. To estimate the differences among the sampling methods and the dilutions tested, multiple linear regression was used. The analysis showed that the number of colonies harvested at dilution 1/40 is 13% higher (P = 0.09) than the number harvested at dilution 1/50 and the number of colonies harvested at dilution 1/30 is 6% higher than dilution 1/50 (P = 0.52). With regard to the comparison between the number of colonies harvested with Rodac contact plates, with cotton pads and DC pads, regression analysis shows that cotton pads harvest a number of fungal cfu 5 times higher than those detected with Rodac plates, while DC pads harvest a number of fungal ufc 6 times higher than those detected with Rodac plates (P < 0.00005). These results, although preliminary, indicate that DC pads are a sensitive and simple approach for the environmental control of fungal contamination.

Diphtheria antitoxin levels in the 14-30-year age group in Italy.

In order to verify diphtheria immunity a seroepidemiological survey was performed in 1996-1997. Serum samples were obtained from 501 subjects 14 years old, recruited at 8 schools in Rome, and from 490 subjects 20-30 years old recruited from 15 Italian regions. Serum diphtheria antitoxin was titrated using the Vero cell assay. The minimum protection level of antitoxin was set at 0.01 IU ml-1. The results show that the younger population have a good immunity to diphtheria while a large proportion of young adults is devoid of protective levels of diphtheria antitoxin. Out of the 501 subjects 14 years old, 495 (98.8%) had a diphtheria antitoxin titre > or = 0.01 IU ml(-1). Only 6 (1.2%) teenagers were susceptible. Out of the 490 subjects 20-30 years old, 109 (22.2%) were susceptible, 381 (77.8%) had a diphtheria antitoxin titre > or = 0.01 IU ml(-1). The data stress for booster immunization at the end of junior high school.

Immunity status against poliomyelitis in persons 13-14 years old living in Rome.

The immunity against poliomyelitis in 1000 subjects 13-14 years old was evaluated. Neutralizing antibodies against poliovirus type 1, 2 and 3 were detected in 97.6%, 95.8% and 70% of samples, respectively. 3/1000 (0.3%) subjects were simultaneously seronegative to the three types. WHO does not suggest a protective level of International Units (IU), but our data indicate that such level is 0.45 IU for polio type 1, 0.65 IU for the type 2 and 0.138 for the type 3. A booster dose of vaccine in adolescence to ensure personal and herd immunity is recommended.

[General practice and preventive activities in a Local Health Unit in Lazio]. / Medicina di base ed attività di prevenzione in una USL del Lazio.

The Authors describe the results of a survey addressed to evaluate GP's opinions and behaviours regarding prevention. The GP's report they offer health informations about cardiovascular diseases and diabetes very often (score 3.6 and 3.4) and junior doctors (under 45 year) satisfy this request significantly more than senior doctors (p = 0.0057). The GP's consider their clinics the best place were to carry out health promotion activities (score: 3.8) and 85% of them would like to have a health promotion centre within their District (in italian: Local Health Unit), mainly to increase the coordination of GP's activities.

Immune response of the elderly to rabies vaccines.

A serological study has been performed to detect the antibody response to full schedules of two anti-rabies vaccines (PDEV and HDCV). Subjects aged > 50 years, compared with subjects 11-25 years, showed significantly lower titres after the 4th dose (and, to a lesser extent, after the 5th dose), suggesting that, among the elderly, the 6th dose is strongly desirable.

Viral hepatitis and drugs: a continuing problem.

A seroepidemiological survey of a group of drug abusers has been carried out to determine the prevalence of hepatitis C virus and hepatitis B virus, hepatitis D virus, hepatitis A virus infection markers in sera, as well as to evaluate the role of potential risk factors. A total of 645 symptomless subjects with a history of injecting heroin were recruited as volunteers from methadone maintenance centres in Rome. For all hepatitis viruses the total figures showed high prevalence rates giving considerable viral circulation in this group. Among heroin addicts the prevalence was 63.4% for HCV, 65% for HBV, 13.3% for HDV and 50.9% for HAV. Anti-HCV prevalence correlated with serological evidence of HBV infection. A significant correlation was also found between presence of HCV antibodies and exposure time to drug addiction > 5 years earlier. The data reveal the important role played by needle sharing in the spreading of multiple infections among intravenous drug abusers (IVDA).

[Tetravalent anti-meningococcal vaccine: serologic and clinical evaluation]. / Vaccino antimeningococcico tetravalente: valutazione sierologica e clinica.

Meningococcal disease is the only bacterial meningitis able to cause an epidemic and the mortality due to this disease is all but negligible; therefore the active immunization induced by a vaccine that includes a large portion of Neisseria meningitidis serogroups responsible for the immunization of subjects at risk. Tetravalent vaccine containing polysaccharides of the serogroups A, C, Y, W135 has given good results both for tolerability and immune response. Considering the epidemic situation in Italy, this vaccine could be an excellent strategy "to behead" possible epidemics and/or hyperendemics due to a known serogroups.

Lymphocyte proliferative response to rabies virus antigen.

Rabies virus (RV) infection, as well as active immunisation using viral antigen, elicit both humoral and cellular reactions whose protective effects are still unclear. We evaluated both responses in order to find valuable monitoring parameters for the immunisation procedure. Three laboratory workers repetitively immunised with booster human diploid cell vaccine against rabies virus, 13 patients from the anti-rabies centre (vaccinated for the first time) and 10 healthy volunteers (not immunised nor exposed to rabies virus antigen), were monitored for: (i) in vivo RV-specific antibody production; (ii) in vitro anti-RV lymphocyte proliferative response and (iii) in vitro phenotype modulation induced by the viral antigen. In particular CD3, CD4, CD8, and surface immunoglobulins were monitored. All 3 subjects receiving the booster immunisation and, to a lesser extent, those receiving 4 doses of vaccine did recognise the antigen in vitro. The proliferation involved mainly CD4 positive cells leading to an increased number of cell bearing surface immunoglobulins, i.e. B cells. The proliferation index was in good correlation with the in vivo antibody production (p = less than 0.00009441). Nevertheless the presence of some cases without correlation between those parameters (in particular 5 out of 6 patients over 65 years of age failed to mount an adequate cellular proliferative response) reveals the need to use cellular response in parallel to the current humoral response, in order to evaluate and monitor the immunisation procedure. This conclusion is further stressed by the fact that protection against rabies infection is mainly cellular.

PCB and other organochlorine compounds in blood of women with or without miscarriage: a hypothesis of correlation.

Polychlorobiphenyls (PCBs) have been shown to affect reproduction in experimental animals and in human beings following intoxication. The concentrations of PCBs and other organochlorine compounds were determined in blood samples from 120 women hospitalized for miscarriages and 120 full-term pregnancy controls. The average PCB hematic level (reported as Fenclor 54) was higher in women with miscarriages than in control women. No differences were detected as far as the hematic concentrations of hexachlorobenzene and DDT compounds were concerned. The reproductive history of each woman was assessed together with confounding variables on the phenomenon of miscarriage and the factors regarding environmental exposure and food intake. Food consumption did not indicate diet as the main source of PCB intake.