Reactive arthritis in a population exposed to an extensive waterborne gastroenteritis outbreak after sewage contamination in Pirkanmaa, Finland.

OBJECTIVES: To assess the occurrence, clinical picture, and triggering infections of reactive arthritis (ReA) associated with a large waterborne gastroenteritis outbreak. METHODS: After an extensive sewage contamination of the water supply system, an estimated 8453 of the 30 016 inhabitants of the town of Nokia fell ill. General practitioners and occupational physicians were advised to refer any patients with suspicion of new ReA to rheumatological examination including faecal culture, human leucocyte antigen (HLA)-B27 and antibody tests for Campylobacter, Salmonella, and Yersinia. RESULTS: Forty-five patients (33 females, 12 males) aged 16-77 years (median 53) were referred. ReA was diagnosed in 21, postinfectious arthralgia in 13, and other musculoskeletal conditions in 11 patients. HLA-B27 was positive in five out of 44 patients (11%). Of the 21 patients with ReA, possible triggering infections were observed in seven (33%), Campylobacter in four, Yersinia in three, and Salmonella in one, who also had Campylobacter infection. ReA was mild in all but one patient who presented with persistent Salmonella enterica serotype enteritidis infection. CONCLUSIONS: Taking into account the large population contaminated with potentially arthritogenic agents, the occurrence of ReA was rare and mild in character.

An extensive gastroenteritis outbreak after drinking-water contamination by sewage effluent, Finland.

An inappropriate cross-connection between sewage- and drinking-water pipelines contaminated tap water in a Finnish town, resulting in an extensive waterborne gastroenteritis outbreak in this developed country. According to a database and a line-list, altogether 1222 subjects sought medical care as a result of this exposure. Seven pathogens were found in patient samples of those who sought treatment. To establish the true disease burden from this exposure, we undertook a population-based questionnaire investigation with a control population, infrequently used to study waterborne outbreaks. The study covered three areas, contaminated and uncontaminated parts of the town and a control town. An estimated 8453 residents fell ill during the outbreak, the excess number of illnesses being 6501. Attack rates were 53% [95% confidence interval (CI) 49.5-56.4] in the contaminated area, 15.6% (95% CI 13.1-18.5) in the uncontaminated area and 6.5% (95% CI 4.8-8.8) in the control population. Using a control population allowed us to differentiate baseline morbidity from the observed morbidity caused by the water contamination, thus enabling a more accurate estimate of the disease burden of this outbreak.

Nosocomial bloodstream infections in Finnish hospitals during 1999-2000.

Prospective laboratory-based surveillance in 4 Finnish hospitals during 1999-2000 identified 1477 cases of nosocomial bloodstream infection (BSI), with an overall rate of 0.8 BSIs per 1000 patient-days. Of BSI cases, 33% were in patients with a hematological malignancy and 15% were in patients with a solid malignancy; 26% were in patients who had undergone surgery preceding infection. Twenty-six percent of BSIs were related to intensive care, and 61% occurred in patients with a central venous catheter. Sixty-five percent of the 1621 causative organisms were gram positive, 31% were gram negative, and 4% were fungi. The most common pathogens were coagulase-negative staphylococci (31%), Escherichia coli (11%), Staphylococcus aureus (11%), and enterococci (6%). Methicillin resistance was detected in 1% of S. aureus isolates and vancomycin resistance in 1% of enterococci. The 7-day case-fatality ratio was 9% and was highest for infections caused by Candida (21%) and enterococci (18%). The overall rate of nosocomial BSIs was similar to rates in England and the United States, but S. aureus, enterococci, and fungi were less common in our study, and the prevalence of antibiotic resistance was lower.

Occurrence of antibodies to teichoic acid in patients with diseases other than staphylococcal infection.

To determine the usefulness of the teichoic acid antibody (TAA) test in conditions where unspecific viral and bacterial antibodies are often encountered, we measured TAA by the gel-diffusion method in 475 patients without known staphylococcal disease; they included 213 patients with arthritis, 108 with liver diseases, 100 with gastro-intestinal disorders and 54 with acute pharyngitis. Positive controls were 104 patients with Staphylococcus aureus bacteraemia and 203 healthy adults were negative controls. Thirteen (6%) of the healthy adults had positive TAA titres (greater than or equal to 4), and the highest titre was 8 in two people (1%). Positive titres were found in 38% of patients with S. aureus bacteraemia and high titres (greater than or equal to 8) were seen in 24%. Among the patients with arthritis, positive TAA titres were found significantly more often than in healthy controls in patients with Yersinia arthritis (p less than 0.01) and systemic lupus erythematosus (SLE; p less than 0.02). In other patient groups, the percentage of positive TAA titres did not differ significantly from that in healthy adults. Eight (2%) of the 475 patients without known staphylococcal infection had TAA titres greater than or equal to 8 but these high titres were not associated with any particular disease group. Only two of these eight patients had slightly raised antibody to staphylococcal alpha-haemolysin. We conclude that the TAA test cannot be used as a reliable indicator of septic staphylococcal disease in patients with Yersinia arthritis or SLE, but that in general, TAA titres greater than or equal to 8 point strongly to S. aureus infection even in patients with autoimmune or liver diseases.

High rates of disseminated infection due to non-tuberculous mycobacteria among AIDS patients in Finland.

OBJECTIVE: to determine the rate of disseminated infection due to non-tuberculous mycobacteria (NTM) among Finnish AIDS patients, and to analyse the epidemiology of these infections. METHODS: in a prospective cohort study HIV-infected patients with CD4 counts < 200 x 10(6)/l were interviewed, and had mycobacterial blood cultures performed at baseline and at 6 months, then subsequently for clinical indications; autopsies were performed on patients who died. The cohort was followed at least for 24 months or to death. Water samples were collected from the homes of patients and from the environment and cultured for organisms of the Myobacterium avium complex (MAC). Environmental and clinical isolates were compared using pulsed field gel electrophoresis (PFGE). RESULTS: NTM infection occurred in 22 (43%) of 51, 19 isolates were Mycobacterium avium, two M. genavense and one M. intracellulare. Multivariate analysis identified urban residence (P=0.04) and eating raw fish (P=0.04) as independent risk factors. Molecular analysis revealed two clusters of related isolates (three M. avium, two M. genavense) among urban residents. CONCLUSION: AIDS patients in Finland have high rates of disseminated infection due to NTM. Clusters of identical organisms and association with urban residence suggests that these are newly acquired infections in advanced AIDS.

Sources of disseminated Mycobacterium avium infection in AIDS.

OBJECTIVES: To identify the sources of disseminated Mycobacterium avium complex (MAC) infection in AIDS. METHODS: HIV positive subjects with CD4 counts <100/mm(3) in Atlanta, Boston, New Hampshire and Finland were entered in a prospective cohort study. Subjects were interviewed about potential MAC exposures, had phlebotomy performed for determination of antibody to mycobacterial lipoarabinomannin and for culture. Patient-directed water samples were collected from places of residence, work and recreation. Patients were followed for the development of disseminated MAC. Univariate and multivariate risk factors for MAC were analyzed. RESULTS: Disseminated MAC was identified in 31 (9%) subjects. Significant risks in univariate analysis included prior Pneumocystis carinii pneumonia (PCP) (hazard ratio 1.821), consumption of spring water (4.909), consumption of raw seafood (34.3), gastrointestinal endoscopy (2.894), and showering outside the home (0.388). PCP, showering and endoscopy remained significant in a Cox proportional hazards model. There was no association between M. avium colonization of home water and risk of MAC. In patients with CD4<25, median OD antibody levels to lipoarabinomannin at baseline were 0.054 among patients who did not develop MAC and 0.021 among patients who did develop MAC (P=0.077). CONCLUSIONS: MAC infection results from diverse and likely undetectable environmental and nosocomial exposures. Mycobacterial infection before HIV infection may confer protection against disseminated MAC in advanced AIDS.