A. Lo Nostro

Experience of hepatitis A vaccination during an outbreak in a nursery school of Tuscany, Italy

An outbreak of hepatitis A started in late October 1996 in a nursery school in Tuscany, Italy. A programme of hepatitis A vaccination without the use of immunoglobulin started at the beginning of December 1996 and included 33 children, 21 household contacts and 6 adults working in the school. Overall, 11 cases occurred in children attending the school (attack rate 27%) and 10 among their household contacts (attack rate 9 %). The latter also included parents, and, in two cases, grandmothers. The data indicate that susceptibility to HAV has increased over recent decades in central Italy. Past and recent experience shows that the usual duration of hepatitis A epidemics in the absence of immune prophylaxis is longer than that described here. The use of hepatitis A vaccine probably contributed to the early extinction of the outbreak, because no further cases were notified in the area after 7 February 1997.

Low prevalence of diphtheria immunity in the population of Florence, Italy

A seroepidemiological study was conducted in 1994 on a representative sample of the population of Florence in order to verify the immunity coverage against diphtheria. Subjects were divided according to sex and age class. Sera from each selected class were at least 1.5/1000 of the residing population. Diphtheria antitoxin was titrated using a quantitative ELISA test. The results show an overall adjusted prevalence of diphtheria immunity (⩾ 0.01 IU/ml) equal to 63.7%. Subjects of younger age classes have good protection levels (85.5% immune under 30 years), while only half individuals aged ⩾ 50 years have antibody titres .⩾ 0.01 IU/ml. Full protection (antibody titre ⩾ 0.1 IU/ml) was detected only in a very small proportion of those aged ⩾ 40 years. Our data show (1) how a recrudescence of diphtheria could theoretically take place in older subjects living in Italy, and (2) stress the importance of periodical re-vaccination of adults.

Prevalence of hepatitis A virus infection in sewage plant workers of Central Italy: is indication for vaccination justified?

Prevalence of antibodies to hepatitis A virus (HAV) was studied in a group of 65 sewage plant workers living in Tuscany, Central Italy. In order to evaluate the effect of several confounders (age, place of birth, income, educational degree, sea-food consumption, etc.), subjects under study were matched with 160 other workers residing in the same area. Anti-HAV was detected in about 51% of sewage workers and 44% of other employees. The difference was not statistically significant. Both univariate and multivariate analysis showed that the main variables related to previous HAV infection were increasing age (P<0.001), birth in Southern Italy (P<0.01) and lower educational degree (P<0.001). Although other studies in Northern and Central Europe showed a slightly higher risk of infection in sewage workers versus general population, lack of evidence of occupational risk in Italy might be explained by the relative importance of a higher degree of viral circulation in the past. The changing epidemiology of HAV infection in Italy with increasing numbers of susceptibles in adults and the potential occupational risk suggest that the present indication to immunize sewage plant workers against hepatitis A should be maintained.

Prevalence of diphtheria toxin antibodies in human sera from a cross-section of the Italian population

A polycentric study was carried out between 1993 and 1995 in order to evaluate diphtheria immunity on a representative sample of population from different areas of Italy. To determine diphtheria antitoxin, sera from 5187 apparently healthy subjects, divided according to sex and age groups, were titrated using an ELISA indirect method. A basic protective titre of diphtheria antitoxin (> 0.01 IU ml-1) was found in 4080 (78.6%) subjects. No statistically significant differences between males and females were observed. Our findings show that the proportion of susceptibles increases with age and a high proportion of adults no longer has diphtheria antitoxin at protective levels since toxigenic C. diphtheriae circulation is presently lacking in Italy.

Anti-Hepatitis C Virus Epidemiological Study in Two Dialysis Centers in Florence

We studied the prevalence and incidence of anti-hepatitis C virus (HCV) antibodies in 350 patients during 15 months and looked for some risk factors. We found a significant correlation between anti-HCV positivity and length of dialysis treatment and treatment in more than one center. We propose some prophylactic rules.

Free-range and organic farming: Eggshell contamination by mesophilic bacteria and unusual pathogens

SUMMARY The high incidence of foodborne illnesses caused by the consumption of eggs in industrialized countries is the main reason we decided to determine the microbial load on the surface of eggshells from free‐range and organic farming. The objective was to compare which was better for ensuring the least possible health risk to the consumers, focusing on consumption of raw eggs by immune‐compromised people. Bacteria come from the intestine of the animal or subsequent contamination. When eggs are cracked, bacteria from the shell reach the yolk and the albumen, and grow during manipulation and preservation, causing foodborne diseases in consumers. Microorganisms such as Salmonella, Listeria monocytogenes, Campylobacter, Enterobacteriaceae (including E. coli serotype O157: H7), Staphylococcus, Enterococcus, and mesophilic aerobic bacteria, were examined. The presence of bacteria on eggshells depends on hygienic conditions of the farming and packaging industries. Hygienic measures, such as strict cleaning and disinfection of surfaces in contact with eggs in packaging industries, would be a protective factor to minimize the contamination of eggshells. The total absence of pathogens demonstrates the relevance for human consumption of eggs coming from both free‐range and organic farms, though YOPI (young, old, pregnant, or immune‐compromised) people preferably should cook eggs in which bacteria contaminating the outer surface are killed.