An Easter outbreak of Salmonella Typhimurium DT 104A associated with traditional pork salami in Italy.

Salmonella enterica is a common cause of gastrointestinal illness in Italy. S. Typhimurium accounts for approximately 40% of isolates, and most of these strains belong to the phage type DT104. We describe the investigation of an outbreak of S. Typhimurium DT104A, a subtype never observed before in Italy, which occurred in Rome during spring 2004.We conducted a matched case control study between 24 July and 9 September 2004. Controls were matched for age and area of residence. Each case had between one and four controls. Odds of exposure to potential risk factors and vehicles for the outbreak were compared between cases and controls. A multivariate analysis was conducted to estimate adjusted Odds Ratios.Sixty-three cases of S. Typhimurium DT 104A infection with onset between 1 April and 5 May 2004 were identified. Sixty-one were residents of Rome and two were residents of a neighbouring region. Twenty-six cases (43%) were enrolled in the study. Their median age was 7.5 years. Fourteen of 26 cases and 16 of 62 controls had eaten pork salami (OR= 25.5; 95% CI 1.6- 416.8). No food samples were available for testing. In northern Italy, two months prior to the outbreak, the veterinary surveillance system identified the first isolation of S. Typhimurium DT104A in a pig isolate. Both human and pig isolates showed indistinguishable PFGE patterns. It was not possible to trace the pig after the sample was taken at slaughter. The epidemiological evidence on the implication of pork salami in this outbreak suggests that pork products can also be a vehicle for salmonella in Italy and underlines the importance of good manufacturing practices for ready-to-eat foods. This investigation highlights the value of laboratory-based surveillance in identifying community-wide outbreaks of uncommon pathogens. It also underlines the need to improve surveillance timeliness, for promptly detecting outbreaks, undergoing field investigation, and implementing control measures. Moreover, our study shows the usefulness of integrated human and animal surveillance in tracing the possible source of infection.

Hepatitis A virus identification in an outbreak by enzymatic amplification.

From April 28th to May 22nd, 1987, the Medical Authority identified 13 cases (6 symptomatic cases) of hepatitis A (HA) in a school and in a college of Rome. The principal risk factor was determined to be "full-time presence at the State school and boarders at the college". The distribution of HA cases suggested a person to person contact; anti-hepatitis A virus IgM were identified in 12 out of 13 cases with high levels of transaminases. During the disease epidemic, water samples were taken from the well of the college for bacteriological and virological analyses. The water was classified as undrinkable due to the presence of 16 total coliforms/100 ml and 35 total bacteria count at 36 degrees C. Fecal coliforms, fecal streptococci and sulfite reducing clostridia were absent. Two water samples of 100 liters were collected and concentrated by adsorption-elution method on electropositive membranes or by ultrafiltration using a Millipore apparatus. Infectious Hepatitis A virus was only isolated from samples concentrated by adsorption-elution method on electropositive membranes using tissue culture methods and subsequently HA virus was identified by other traditional methods (Elisa and immunofluorescence). In contrast, PCR test performed on the concentrated samples, was positive only for the ultraconcentrated sample. The positivity of the PCR test confirmed the presence of the Hepatitis A virus in the well water.

Survey on tuberculosis reports in a major Italian region.

A survey was carried out on all cases of pulmonary and extrapulmonary tuberculosis reported in the Latium region of Italy during 1986, in order to characterize them from bacteriological and epidemiological points of view. A total of 497 TB notifications were investigated; reliable medical records were traced and consulted for 458 of these. Seventy-six percent of cases was classified as respiratory tb, 21.8% non-respiratory tb and 2% both. Ninety-two percent of all cases had been hospitalized for long periods (mean: 69 days/median: 63 days for cases of respiratory TB and mean: 40/median 29 days for non-respiratory patients). Contrary to the definition of a reportable case in Italy, evidence of Mycobacteria on direct or cultural examination was present in only half of all reported patients. Twenty-seven percent of respiratory cases and 33.3% of non-respiratory had a previous diagnosis of TB mentioned on the clinical record. High daily alcohol intake is reported more frequently among TB patients with respect to the general population, while drug abusers, immigrants and HIV seropositives represent a very low proportion. Delays in notification have been observed and current notification system is evaluated.