A nationwide outbreak of Salmonella enterica serotypes Newport and Reading occurred between 17 October and 28 November 2008 in Finland. A total of 77 culture-confirmed Salmonella Newport and 30 Salmonella Reading cases, including one case with a double infection, were reported. All strains isolated from the patients were subtyped using serotyping, microbial resistance profiling, and pulsed-field gel electrophoresis (PFGE). Here, the PFGE patterns of the studied Salmonella Newport strains were identical, whereas four different PFGE profiles were found among the Salmonella Reading strains. Two elderly patients died within 2 weeks of the onset of symptoms. Three geographical clusters of cases with an epidemiological link were identified. The traceback investigation suggested that the factor connecting the cases was ready-chopped iceberg lettuce available for mass catering use. However, none of the tested food, environmental samples, or the samples taken from the staff of the processing plant contained Salmonella bacteria. Tracing back to outbreak sources with a short shelf life can be complex.

Educating the public in endemic areas to avoid mosquito exposure and use protective measures remain important prevention measures for SINV infection.

Background Neisseria meningitidis is an encapsulated Gram-negative diplococcus that asymptomatically colonises the upper respiratory tract in up to 25% of the population (mainly adolescents and young adults). Invasive meningococcal disease (IMD) caused by Neisseria meningitidis imposes a substantial public health burden,. The case fatality rate (CFR) of IMD remains high. IMD epidemiology varies markedly by region and over time, and there appears to be a shift in the epidemiology towards older adults. The objective of our review was to assess the published data on the epidemiology of IMD in older adults (those aged ≥ 55 years)in North America and Europe. Such information would assist decision-makers at national and international levels in developing future public health programmes for managing IMD. Methods A comprehensive literature review was undertaken on 11 August 2020 across three databases: EMBASE, Medline and BIOSIS. Papers were included if they met the following criteria: full paper written in the English language; included patients aged ≥ 56 years; were published between 1/1/2009 11/9/2020 and included patients with either suspected or confirmed IMD or infection with N. meningitidis in North America or Europe. Case studies/reports/series were eligible for inclusion if they included persons in the age range of interest. Animal studies and letters to editors were excluded. In addition, the websites of international and national organisations and societies were also checked for relevant information. Results There were 5,364 citations identified in total, of which 76 publications were included in this review. We identified that older adults with IMD were mainly affected by serogroups W and Y, which are generally not the predominant strains in circulation in most countries. Older adults had the highest CFRs, probably linked to underlying comorbidities and more atypical presentations hindering appropriate timely management. In addition, there was some evidence of a shift in the incidence of IMD from younger to older adults. Conclusions The use of meningococcal vaccines that include coverage against serogroups W and Y in immunization programs for older adults needs to be evaluated to inform health authorities’ decisions of the relative benefits of vaccination and the utility of expanding national immunization programmes to this age group.

More efforts should be focused on disseminating pre-travel advice to immigrants planning to visit friends and relatives and travelers on self-organized trips.

Pogosta disease is a viral disease caused by a mosquito-borne alphavirus, Sindbis virus (SINV), and large human outbreaks of SINV infection have emerged in Finland every seven years. After a major outbreak in 2002 an epidemic was expected to take place in 2009. Data from the National Infectious Disease Registry showed a small outbreak in humans in 2009 with a total of 105 reported cases but the seven-year cycle did not recur as anticipated.

Background Invasive meningococcal disease (IMD) causes high fatality in untreated patients alongside long-term sequelae in 20% survivors. For a comprehensive assessment of epidemiology, an analysis of these sequelae is required. This study aims to investigate the epidemiology of disease between 2008 and 2017 including a description of the sequelae, through the analysis of data collected from the UK Clinical Practice Research Datalink (CPRD) linked with data from the Hospital Episode Statistics (HES), and Office for National Statistics (ONS) mortality registry data. Methods This was a 10-year retrospective observational cohort study designed to describe the incidence, case-fatality rate (CFR) and occurrence of sequelae due to meningococcal disease, in the UK between 2007 and 2017 using data from the UK CPRD-HES-ONS. Cases were identified and matched on age, gender, date of diagnosis of IMD and followed-up-time with a control group without IMD. Demographics, clinical characteristics, mortality, and IMD-related sequelae were examined for IMD cases and compared with matched controls for a more comprehensive assessment. Results The study analysed 640 IMD patients with majority of the cases diagnosed (76.9%) in a hospital setting. Age-group analysis showed a decrease in the incidence rate of IMD in patients aged <1 year (30.4 – 7.5%) and an increase in those >50 years (10.4 – 27.8%). CFR was slightly higher among females, toddlers, and adults >50 years. No significant change in CFR was observed over study period. Case-control study showed a higher number of IMD sequelae among cases compared to age- and gender-matched controls, especially in those ≥ 50 years. Conclusion The study showed that, despite a relatively low incidence rate, IMD is responsible for a high CFR, namely in older age groups and by a high number of IMD sequelae. The study showed that leveraging data from existing databases can be used to complement surveillance data in truly assessing the epidemiology of IMD. Despite the availability of routine vaccination programs, IMD still poses a significant burden in the healthcare system of the UK. Optimization of vaccination programs may be required to reduce the disease burden.

Salmonella enterica serotype Bovismorbificans is a rare serotype in Finland. In June 2009, a nationwide outbreak of S. Bovismorbificans infections occurred, and 42 clinical isolates were identified. We conducted a case-control study enrolling 28 cases and 48 matched controls, and found ready-to-eat alfalfa sprouts associated with the infection (odds ratio = 35.2, 95% confidence interval 2.8-435). The sprouts were traced back to a domestic producer, with the seeds originating in Italy. Although finding microbiological evidence for sprouts as a source of this outbreak was very challenging, S. Bovismorbificans was finally found in sprouts germinated in the laboratory, and in soaking and rinse waters during the germination process. The pulsed field gel electrophoresis showed that these isolates were identical to the human outbreak isolates. Before sampling, it is important to mix the seeds well and to take several large-size samples from different seed lots. Instead of analysing seeds, the analysis should be targeted to soaking or rinse water samples and to the sprouts germinated in a laboratory. Accordingly, the sprout producers should only buy seeds that have been analysed for Salmonella. The producers have to include Salmonella testing in their internal quality control to ensure that Salmonella is absent from sprouts placed on the market during their shelf-life. In order to reduce the health hazard caused by sprouts, an effective and safe decontamination procedure should also be developed for the seeds.

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