Abstract: AIMS: Legionella contamination of industrial cooling towers has been identified as the cause of sporadic cases and outbreaks of legionellosis among people living nearby. To evaluate and control Legionella contamination in industrial cooling tower water, microbiological monitoring was carried out to determine the effectiveness of the following different disinfection treatments: (i) continuous chlorine concentration of 0.01 ppm and monthly chlorine shock dosing (5 ppm) on a single cooling tower; (ii) continuous chlorine concentration of 0.4 ppm and monthly shock of biocide P3 FERROCID 8580 (BKG Water Solution) on seven towers. METHODS AND RESULTS: Legionella spp. and total bacterial count (TBC) were determined 3 days before and after each shock dose. Both strategies demonstrated that when chlorine was maintained at low levels, the Legionella count grew to levels above 10(4) CFU l(-1) while TBC still remained above 10(8 )CFU l(-1). Chlorine shock dosing was able to eliminate bacterial contamination, but only for 10-15 days. Biocide shock dosing was also insufficient to control the problem when the disinfectant concentration was administered at only one point in the plant and at the concentration of 30 ppm. On the other hand, when at a biocide concentration of 30 or 50 ppm was distributed throughout a number of points, depending on the plant hydrodynamics, Legionella counts decreased significantly and often remained below the warning limit. Moreover, the contamination of water entering the plant and the presence of sediment were also important factors for Legionella growth. CONCLUSIONS: For effective decontamination of outdoor industrial cooling towers, disinfectants should be distributed in a targeted way, taking into account the possible sources of contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: The data of the research permitted to modify the procedure of disinfection for better reduce the water and aerosol contamination and consequently the exposure risk.
Abstract: AIMS: The purpose of this work was to verify whether E. coli is a good indicator of viral contamination in mussels and Adenovirus could represent a better alternative as indicator organism of viral presence to guarantee consumer health protection. METHODS AND RESULTS: Eighty samples of mussels from La Spezia Gulf were analysed for E. coli, Salmonella, Adenovirus, Norovirus and hepatitis A virus with cultural and biomolecular tests. The results of bacterial parameters showed E. coli within the law's limits and the absence of Salmonella. Twelve samples were positive for Adenovirus presence, one for Norovirus genogroup II and two for hepatitis A virus. None of these positive mussels was found to be contaminated with more than one virus at the same time. CONCLUSION: This study showed that there was not a direct correlation between the presence of human pathogenic viruses and bacterial indicators. SIGNIFICANCE AND IMPACT OF THE STUDY: Both E. coli and Adenovirus cannot be considered valid substitutes for the direct research of human pathogenic viruses in mussels. To improve consumer health protection, the European Commission will provide standardized methods for Norovirus and hepatitis A virus detection as soon as possible.
Abstract: BACKGROUND: Bacterial contamination of spirometers has been documented in water-sealed devices, mouthpieces, and connection tubes. Little information is available about bacterial contamination of flow-based apparatuses such as turbine-type spirometers and pneumotachographs. Inspiration through contaminated equipment is a potential source of cross infection. To investigate bacteria mobilization (ie, bacteria detachment and aerosolization from the instrument) during routine spirometric testing, 2 types of flow-based spirometers were used. Bacteria mobilization during artificial inspiration through in-line filters or cardboard mouthpieces was evaluated. METHODS: Nine hundred workers undergoing periodic spirometric testing were enrolled at the occupational physician office in 30 sessions of 30 subjects each. The participants were asked to perform a forced vital capacity test in a turbine-type spirometer and in an unheated pneumotachograph fitted with disposable in-line filters or cardboard mouthpieces. To evaluate bacterial mobilization, an artificial inspiration was performed and bacterial growth determined. The bacterial growth analysis was assessed after the first and the thirtieth spirometric tests of each session without disinfecting the instruments between tests. In addition, instrument bacterial contamination was evaluated. RESULTS: No significant bacterial mobilization and instrument contamination were found in spirometric tests executed with in-line filters. Conversely, a significant bacterial mobilization and instrument contamination were observed in tests performed with cardboard mouthpieces. Differences between the 2 spirometers were not significant. CONCLUSION: In-line filters may effectively reduce the risk of bacterial cross infection. Inspiration through flow-based spirometers fitted with disposable cardboard mouthpieces is completely safe when combined with spirometer disinfection/sterilization between subjects.
Abstract: Municipal and agricultural wastewater contain a variety of microorganisms and in particular enteric viruses. For the reuse of this treated wastewater it is important to ensure the efficiency of purification treatments and disinfection practices, that have often been insufficient to lower the viral load below the risk level. For this reason, for the routine analysis of recycled waters, the research into pathogenic viruses (e.g. HAV) and classical bacterial parameters (E. coli, enterococci and Salmonella) has to be associated with specific viral indicators such as somatic coliphages, adenovirus and TTV. The results of environmental monitoring, carried out in a wastewater treatment plant, showed the presence of adenovirus DNA in 100% of collected samples and TTV DNA in 95% (19/20) of raw sewage and in 85% (17/20) of the exit samples, while HAV was detected only in 2 samples over 40 (5%). The quantitative analysis has revealed an average reduction of 2 log for adenovirus and 1.58 log for TTV. The bacterial indicators were reduced by 1.74 log and 1.99 log respectively for E. coli and enterococci, while for somatic coliphages an average reduction of 2.2 log was observed. No significant correlation was shown between these parameters, confirming their inadequacy for the virological risk assessment. However the results of adenovirus confirm it as the best indicator to evaluate the efficacy of wastewater depuration plant in eliminating viruses.
Abstract: Although the fractured aquifer of the Salento supplies over 80% of the drinking water requirements of the local population, its exposure to pollution has recently increased. In recent years, owing to the arid climate and droughts, the spreading of wastewater on soil for irrigation has become much more frequent. Consequently, hazardous and pathogenic microorganisms released with wastewater have been transported into the subsoil and have contaminated groundwater. An elaboration of epidemiological data has shown that the local population has the highest exposure to endemic gastroenteritis in Italy. In order to reduce human exposure to unsafe groundwater, the setback distance for drinking wells necessary to achieve the 'natural disinfection' criteria, has been determined experimentally at the Nardò aquifer (Salento region), supported by groundwater monitoring results and a mathematical transport model able to determine the apparent pathogenic microorganism pathways in fractures. The results also provided valuable inactivation constants of cultural indicators (coliforms, enterococci, Clostridium spores and somatic coliphages) and viruses in the wastewater that have been injected into the fractured aquifer since 1991. Furthermore, the efficacy of chlorine to remove viral indicators from water in a well 500 m from wastewater injection was tested. Hypochlorination reduces somatic coliphages and Clostridium spores in groundwaters but did not achieve complete inactivation in all tests. Complete disinfection of groundwater samples was possible only when there was an initial Clostridium spores count of < or = 10 CFU 100 ml (-1).
Abstract: Torque teno virus (TTV) is prevalent worldwide in general populations but at present is not related with any specific pathology. Its presence in faeces and its remarkable environmental stability suggest the possibility of using it as an indicator of faecal contamination in the environment. To evaluate the waterborne spread of TTV and its possible relationship with human pathogen enteric viruses, water samples were collected monthly for a year (May 2004-April 2005) from a river receiving the effluent of the treatment plant of the city of Pisa, concentrated and assayed with bimolecular tests (PCR, RT-PCR). TTV was detected in three samples (25%) while 16% of samples were positive for enteroviruses, 33% for rotaviruses, 8% for noroviruses genotype 1 and 25% for noroviruses genotype 2. Only two TTV samples (June and January) were also positive for rotavirus and norovirus, respectively. The detection of TTV in water confirmed its possible faecal-oral route of transmission but data are still insufficient to draw conclusions about the role of TTV as a viral indicator.
Abstract: In the aim of studying possible relations between viruses detected in clinical specimens and the ones found in different environmental matrices, in the period May 2004 to April 2005, the collection of faecal samples from gastroenteritis cases and the monthly monitoring of raw and treated wastewater, river water, seawater and mussels were carried out. The viruses considered for environmental monitoring were adenovirus, rotavirus, enterovirus, norovirus, hepatitis A virus (HAV) and Torque teno virus (TTV): they were searched for with PCR and RT-PCR and confirmed by gene sequencing. Faecal coliforms and somatic coliphages' counts were also determined. The surveillance of case detected 45 positive faecal samples out of 255 (17.6%) while 35 of 56 environmental samples (62.5%) resulted positive for at least one of the considered viruses. The detection of the same viral strain in the faeces of gastroenteritis cases and in water was possible for adenovirus and rotavirus, which were also predominant in environmental matrices; thus they could be considered as a reference for risk assessment.
Abstract: Aerosol from activated mud decontamination plants used for the treatment of urban sewage can represent a vehicle for bacteria, virus and fungi. As a result, they become an infective hazard for plant personnel, the general population residing in the surrounding area and the occasional visitor. The present investigation focuses on the identification of enteric-type viruses in this kind of aerosol. The following methods were employed on 214 samples collected in the 1999-2000 period: cell culture (BGM, RD, Hep-2), electron microscopy, and polymerase chain reaction (PCR). Cytopathic effect was mild in 180 samples, and severe in 14, upon their first passage in culture. Virus identification was based on positivity to both electron microscopy (EM) and PCR. Thus, one positive sample was recognized to be of enteric-type virus and two positive samples were recognized as reovirus-type. All samples were negative for Norwalk-type virus or HAV. There was considerable discrepancy between electron microscopy and PCR concerning the number of enteric-type viruses recognized. A possible explanation is contamination with animal-type enterovirus.
Abstract: The aim of this study was to determine whether testing for faecal contamination of water through evaluation of traditional bacteriological indicators, as per Directive EEC 76/160, effectively correlates with the presence of viruses in water. The study was performed both on water samples and bivalve molluscan shellfish (Mytilus galloprovincialis) with the further objective of evaluating whether mussels could be used as bioindicator organisms for assessing faecal pollution of water. Overall, 23 sea-water samples and the same number of mussels, taken from three sites along the Salento coast in southern Italy, were analysed to detect total and faecal coliforms, faecal streptococci, E. Coli, Salmonella and enteric viruses. The results of the study confirm that viruses and bacteria do not always follow the same trend. In fact, in one of the two water samples which tested positive for viruses, bacteriological indicators of faecal contamination were found to be below the limits established by current legislation and Salmonellae were absent. Similar results were obtained in the sample of mussels which tested positive for viruses. Conflicting results were obtained in the two examined matrices. This study highlights the importance of searching for viruses in the water environment and the possibility of using mussels as bioindicators for monitoring virological quality of coastal sea-waters.
Abstract: The present study was performed in order to obtain reliable and applicable techniques of viral detection in shellfish for use in ensuring food safety. This research was developed in two steps: (a) different techniques to recover viruses from artificially contaminated shellfish were tested and (b) the best technique was applied to analyse shellfish collected from sites along the coast of Salento.
Abstract: This work was aimed at studying cytopathogenic agents isolated from the environment by adopting, in parallel, various techniques currently used in clinical virology. The purpose of this research was not only to identify the viral species isolated but also to verify the most reliable protocols for environmental applications.
Abstract: Surveys on life and health conditions of university students besides providing useful epidemiologic data partly related to the young population. They are potentially useful for the intervention planning aimed to remove possible environmental or behavioural risk factors. Following these purpose a survey sample about 1200 student attending the University of Pisa was carried out through an anonymous questionnaire about 41 questions focused on behaviours and lifestyles of young people, possible health problems, self-perception of the health state, the use of public health services, and the more commonly used (or preferred) sources of information on health topics. The results suggest that although the self perception of the state of health is broadly positive for the majority of students, there is also a significant frequency of individuals declaring significant at risk behaviours (persistence of sexual practices at risk, drug use, alcohol and smoke abuse). The consumption, also sporadic, of psicoattive substances has been declared gives beyond 40% of the students, in particular 37% asserts to have tried drugs. The habit to smoke appeared diffused much between the students; the percentage of smokers turns out equal to 41% in total (40% females, 42% males). 76% of the interviewed ones has declared to be sexually active, the percentage of those who have declared multiple relations or occasional is elevated (12%), and 47% of the students asserts to use the condom with fixed partner and 77% with occasional partner. Moreover there seems to be a significant association between the changes in the diet and other lifestyles that are due to the "university lifestyle" (as a consequence of leaving the family or increased commuting) and the insurgence of several types of sickness, e.g. gastroenteric disturbances and fever attacks. Finally, the present investigation suggests that few interventions on services offered to students (such as accommodation, teaching structures and especially the creation of a "health office" where students can acquire information on health and other topics related to their condition) could have a significantly beneficial impact on the general state of health of the university population.
Abstract: Deep groundwater, even if generally protected, could be contaminated by surface or rain water infiltration through soil fractures, septic tanks, cesspits, land irrigation, disposal of wastewater and disposal of muds from depuration systems. The sanitary importance of such possible contamination is related to the different uses of the water and it is at the maximum level when it is intended for human use. Routine microbiological analyses do not consider viruses, only bacterial parameters, as contamination indicators. However, it is known that enteric viruses can survive a long time in deep aquifers and that they may not always be associated with bacterial indicators. The virological analysis of waters intended for drinking use is provided only as an occasional control exercised at the discretion of the sanitary authority. Technological difficulties with obtaining data about groundwater viral contamination led to a study to devise rapid and efficient methods for their detection and the application of these methods to samples from different sources. Four acid nucleic extraction techniques have been tested (classic proteinase K- phenol/chloroform, QIAamp Viral RNA Kit (Qiagen), SV Total RNA Isolation System (Promega) and NucleoSpin Virus L (Macherey-Nagel). Sensitivity and specificity of RT-PCR protocols for entero- (EV), hepatitis A (HAV) and small round structured (SRSV) viruses have been verified. Deep groundwater samples (100 L) were concentrated (2-step tangential flow ultrafiltration) and the concentrate contaminated with serial 10-fold dilutions of a known titre of poliovirus type 3. Extracted RNA was concentrated (microcon-100) and analysed by RT-PCR using specific EV primers and visualising amplification products by agarose gel electrophoresis. In addition, two different methods of RT-PCR for non-cultivable viruses have been tested: (a) RT-PCR and nested RT-PCR for HAV and (b) RT-PCR with generic primers and RT-PCR with specific primers for SRSV. Different specificity tests have been carried out in the presence of some of the commoner microorganisms. The most efficient, sensitive and specific protocols were used to test 35 x 100L deep groundwater samples. Sample concentrates were split with one part treated with chloroform and analysed by cell culture (BGM and Frp/3, derived from FrHK/4, cells) and the other tested by RT-PCR for HAV, EV and SRSV. Results demonstrated the high efficiency of the classic and QIAamp methods. Microcon-100 did not increase the sensitivity of the technique used. The highest sensitivity was observed for RT-PCR with specific primers for SRSV and for nested RT-PCR for HAV. One sample showed a cytopathic effect, not confirmed at the third subculture, while the RT-PCR allowed the detection of echovirus 7. Cell culture did not allow detection of the majority of the enteric viruses while PCR gave sensitive, specific and rapid detection of a range of agents in the same samples. Even if it was impossible to fix a virological quality standard, it would be necessary to find a viral indicator in order to achieve a complete preventive check which would be particularly useful in some cases (e.g. water never used before, after pollution accidents, for seasonal checking).
Abstract: AIMS: The risk of hepatitis C virus infection in hospital environments can be assessed not only by studying epidemiological data and work practices, but also by the detection of these viruses (or indicators thereof) in health-care settings, on instruments etc. METHODS: Since standardized techniques specific to this end do not exist, this study was undertaken to apply methods currently used on clinical samples to the assessment of environmental HCV risk, either through direct detection of the virus (RT-PCR), or by probing for haemoglobin as a potential indicator of blood contamination. The tested techniques were applied in a trial environmental monitoring programme undertaken in various hospital laboratories and clinics, during which total bacterial count determinations were performed in parallel with haemoglobin and hepatitis C virus detection. SIGNIFICANCE AND IMPACT OF THE STUDY: The data indicate that the applied methods are of value in detecting low levels of contamination in a hospital environment.
Abstract: AIMS: Faecal material from raw sewage or other sources lacking effective treatment sometimes contaminates water for human consumption. The relevant Italian regulations therefore call for testing drinking and recreational water for the presence of enterovirus. METHODS AND RESULTS: Traditional methods of analysis are based on revealing the typical cytopathic effects of enterovirus on cell cultures. However, the presence in environmental samples of different types of virus may cause interference phenomena that mask such cytopathic effects. The paper reports on an experimental test of this interference hypothesis. Buffalo Green Monkey cell cultures were co-infected via mixed suspensions of the polio type 3 virus and reovirus type 1. Cytopathic effects were then sought and the presence of enterovirus tested for via RT-PCR. CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: The results obtained indicate that the normally high sensitivity of tests for the detection of enterovirus in samples is considerably decreased by the simultaneous presence of reovirus.
Abstract: The frequent occurrence of reoviruses in environmental samples could be a potential source of interference with enterovirus detection, especially when enterovirus isolation on cell culture is required. In order to evaluate new virus-based criteria for enforcing recreational water quality standards, a new method based on a broad reverse transcribed polymerase chain reaction (RT-PCR) was set up to detect reoviruses. Two primers were engineered to amplify a 538 base pair fragment of the Sigma 2 gene. Reovirus strains obtained from ATCC (Jones, Lang, Dearing, Abney, NC-TEV, SV59 and SV12) were used as references. Twenty-four samples of 101 were collected from two beaches of the Adriatic sea and 12 from the neighbourhood of Fano Harbour Channel. The presence of environmental reoviruses was tested on both concentrated seawater samples and lysates of BGM cells infected with the concentrated seawater samples. The new method was used in parallel with the detection of a 3:3:4 electrophoretic pattern of reovirus RNA in polyacrylamide gel electrophoresis (PAGE). Enterovirus and bacteria were also screened in compliance with EEC directives. No enteroviruses were isolated, and it was not attributable to reovirus interference. All the reovirus found by PAGE (8/72) were confirmed by RT-PCR, while several genomes (14/72) were detected only by RT-PCR. Presumptive methods of virus identification, that is CPE on BGM cells and haemagglutination test, were not able to detect them. The specificity of RT-PCR products was checked by direct nucleotide sequence analyses of the amplicons. The phylogenetic analyses showed heterogeneous taxa including human and animal reoviruses, with strong evidence that they were spreading consistently from the Harbour-Channel. This novel approach for reovirus detection will be very useful as a trace route of faecal pollution; more importantly, it could be very useful in contributing to the creation of a databank of circulating enteric viruses.
Abstract: In order to evaluate possible indicators of viral aerosol contamination in sewage treatment plants, a year-long study was carried out on the relationships between the presence of cytopathogenic viruses and the counts of total bacteria, faecal streptococci and somatic coliphages in samples collected at various distances from the aerosol source (aeration tank). The activated sludge plant studied proved to be a significant source of microbe-bearing aerosol with high levels of viral contamination. When the virus was found in sewage, it was also found in the air, at least in the sites closest to the aeration tank. With regard to the possibility of using the chosen parameters as markers of viral contamination, the total bacteria and faecal streptococci counts were generally positively correlated with viral presence, while coliphage counts yielded no analogous relationship.
Abstract: Three immune-enzymatic tests for urinary HIV antibodies were examined in order to assess their sensibility, specificity and delta value. The highest sensibility was noticed for the Seradyn test (98.8%), followed by the Wellcozyme test (98.1%) and finally the SUDS rapid test (56.8%). The resultant specificity was 98.5% for the Seradyn test, 91.3% for the Wellcozyme test and 97.3% for the SUDS test. The measurement of delta value showed a higher capability of discrimination for Seradyn test, that could be considered the most reliable for epidemiological purposes.
Abstract: Hypertriglyceridemia has frequently been found both in subjects with AIDS and in asymptomatic HIV-positive ones. In order to evaluate the importance of hyperlipemia as an index of the clinical evolution of HIV infection, the levels of triglycerides, total cholesterol and CD4 lymphocytes were determined over a period of 2 years in 8 haemophiliacs with AIDS, 13 asymptomatic HIV-positive and 45 HIV-negative haemophiliacs attending the Operative Unit of Coagulation Disorders of the University of Pisa. The mean concentration of triglycerides and incidence of hypertriglyceridemia were significantly higher in haemophiliacs with AIDS, compared with HIV-negative subjects (p<0.0001), while the triglycerides values of asymptomatic HIV-positives fell between those of the other groups. Cholesterol levels were lower in HIV-positive haemophiliacs and in those with AIDS compared with HIV-negatives. No correlation was found between triglyceride levels and those of CD4 lymphocytes.
Abstract: In order to evaluate the AIDS related sources of information, knowledge, attitudes and behaviours among male young people it was filled in a multi-choice anonymous questionnaire by 2018 subjects, called for the first medical examination to Italian Navy and by 1348 recruits. The data from the latter group were used to make comparisons with our previous survey carried out in 1988. The most important sources of information on AIDS were mass media and school, on sexuality friends and family. AIDS awareness was greater among the high educated subjects and positively influenced by mass media and school as sources of information. In agreement with these data, knowledge was better about AIDS than about sexuality. Risk perception was positively influenced by the AIDS-related knowledge for called youth and a greater intolerance towards infected people was observed among the less educated and the less AIDS-aware subjects. On average 46% of the called up young men and 74% of recruits declared to be sexually active: among these, the mean age at the first sexual intercourse was 16, over 60% declared to have had multiple partners, over 30% unknown partners and over 30% didn't use condoms; 20% of called up and 38% of recruits indicated 2 or 3 risk behaviours. Factors determining sex-related risks were different according to the behaviour and the considered group. These results suggest that it is important for young people to be well informed about sex and AIDS before the beginning of sexual activity, if possible during compulsory school.
Abstract: Coliphages and enteroviruses were monitored over 12 months in sewage and air adjacent to an activated sludge plant. Both showed temporal variation but the mean count of phages in enterovirus-positive samples was not significantly different from that in enterovirus-negative samples. Hence coliphages are not necessarily a good indicator of enteroviruses in sewage and aerosols.
Abstract: In order to study the serological status of a population against poliomyelitis, neutralizing antibody for the three types of polioviruses were examined in 742 serum specimens from individuals aged from 1 to 70 years and over were collected during 1985. Sixty-two percent of the sera had antibodies (titre greater than or equal to 1:8) to all three polioviruses, while 5% had no poliovirus antibody at all. However the rates of seropositivity did vary with age: the 10-19 age group had the lowest frequency of antibody (38%) to the three viruses and the difference between the percentage of this group and the previous (1-10 years) and following ones (20-70 years and over) was highly significant. The results of this seroprevalence survey indicate a gap in immunity to poliomyelitis in the population examined.
Abstract: To evaluate the usefulness of anti-HIV mass screenings, we examined 662 new military recruits and 1353 soldiers being discharged. None of the former and only one of the latter (0.07%) resulted seropositive on repeated ELISA and Western-blot. For comparison we also report the results of routine anti-HIV antibody testing in our diagnostic laboratory: the highest proportion of seropositive subjects was found among symptomatic patients (79%), followed by haemophiliac patients (31%), drug addicts (24%), sexual partners of seropositive subjects (21%), prisoners (5%) and homosexual men (5%). Health care personnel and prison guards were all negative. These data confirm that in Italy HIV infection is still relatively confined to the classic risk groups. While generalized screening during military service seems to be excessive, periodic sample surveys could be very useful to follow the evolution of HIV epidemiology.
Abstract: The mutagenic activity of airborne particulate matter collected in Pisa, a small nonindustrial town located in Italy, has been monitored over 1 year using the Ames Salmonella Test. Airborne particulate was collected on fibreglass filters using a Hi-Vol sampler and extracted by sonication and Soxhlet acetone extraction in sequence. TA 98 and TA 100 salmonella strains gave positive results with the great majority of samples. The mutagenicity trend fits with a harmonic regression with a peak during December/January and inversely correlates with the temperature. No correlations were observed with other meteorological conditions such as wind, cloud, rainfall, atmospheric pressure, and humidity. The ratio between mutagenicity/microgram of particulate matter with S9 and that without S9 remains more or less constant regardless of seasonal fluctuations, suggesting that during cold months quantitative increases of mutagens onto particulate matter have probably occurred. The comparison of air mutagenicity in different sites suggests that motor vehicle exhaust fumes are the major source of air pollution. Finally, because of high-traffic volume, air mutagenicity at street level is comparable to that observed in several metropolitan areas all over the world.
Abstract: A mathematical model has been developed which allows estimation of the epidemiological and economic effects of different tetanus vaccination strategies. The model was used to simulate the epidemiology of tetanus in Italy from 1955 to 1982, and then applied to a district of Tuscany by utilizing data obtained from a seroepidemiological survey carried out in the same area. For this district we simulated vaccination programmes designed to reach, within 1 or 10 years, coverages of 60 or 90% of the population aged over 10 years who had not been exposed to the neonatal vaccination programme. The most effective strategy, from both the epidemiological and economic point of view, seems to be 90% coverage reached in 1 year's time. Benefits would be increased by improving the reliability of vaccinal anamnesis.
Abstract: A total of 194 stool samples from sick and healthy children were tested by three commercial tests: two Rotavirus enzyme-linked immunosorbent assays (ELISA) and one latex agglutination test (LTX). The concordance, sensibility and specificity of these tests were calculated. The results suggest to consider as positive the samples reactive to two enzyme immunoassays at least. The latex test, although less sensitive than Enzygnost-Rotavirus and Rotazyme II, was found to be especially useful for the rapid diagnosis of rotavirus gastroenteritis when used to test the first available stool sample from acutely ill patients.
Abstract: Between January 1986 and January 1989, 524 non-typhoid salmonella strains, of which 4 (0.8%) from urine, were isolated at the Microbiology Laboratory of Department of Biomedicine (University of Pisa). These strains were isolated from a man with systematic lupus erythematosus, from two little girls with structural defects of the lower urinary tract, and from a woman with ulcerous colitis. Except the last case, the others were associated with immunological or structural abnormalities that are thought to predispose to salmonella infections.
Abstract: In order to assess protection level against tetanus, the antitoxin titre was evaluated, by indirect haemagglutination test, in a sample, stratified by sex and age, of 805 subjects of three communes of Tuscany. On the whole the frequency of the serum protected is the 46.1% and it varies according to sex and age: under 20 years it is more than 90%, but it decreases in the successive ages, less in the male sex, probably owing to the vaccination made during the military service. The greatest percentage of immune subjects was observed in the most industrialized area. The less protected professional categories were pensioned people and housewives (25.8%). No differences of serum protection were found between those who practise or do not, recreative activities at the risk (sport, horticulture and gardening). No correlation was observed between the vaccinal anamnesis and the serological test.
Abstract: Cyclophosphamide (CP)-induced micronuclei were evaluated in females of two strains of mice (C57BL and CD1), in F1 hybrid females and in fetuses (day 13 of gestation) obtained from different crosses. F1 adult hybrids from a cross between the strain with a high level of induced micronuclei (C57BL) and the strain with a low response (CD1) exhibited micronuclei values closer to the latter. CD1/CD1 fetuses showed a higher susceptibility than C57BL/C57BL ones. Heterozygous fetuses from reciprocal crosses, whatever the maternal genotype, showed the same sensitivity, which is very close to that of C57BL/C57BL fetuses. Phenobarbital (PB) pre-treatment modified the mutagenic response to CP depending on the genotype of the treated animal. These results demonstrate that the response to a pro-mutagen requiring metabolic activation depends to a large extent on the genetic background of the target animals, and that mother-fetus interactions in transplacental mutagenesis seem to depend more on the fetal than on the maternal genotype.
Abstract: Serotyping of Pseudomonas aeruginosa by Fisher's schema has been used to study the prevalence of particular immunotypes among strains of P. aeruginosa obtained from clinical specimens. About 78% of the isolates were serotypable and about 22% were not. Immunotypes 2 and 6 turned out to be the most prevalent, whereas immunotypes 5 and 7 were the least frequent. Immunotypes 2, 5, 6 and 7 did not vary significantly as far as frequency in the various sources is concerned, with the exception of immunotype 2, which was significantly less frequent in isolates from the expectorated sputum. In such isolates immunotype 3 was significantly more frequent than in other sources, whereas immunotype 4 was significantly more frequent in isolates from the feces. It was next investigated whether a correlation exists between antibiotic susceptibility and particular immunotypes. A high percentage of the non-typable strains and of those belonging to immunotypes 2 and 6 proved to be resistant to the antimicrobial agents tested.
