Enteropathogens in acute diarrhea: a general practice-based study in a Nordic country.

The epidemiology of infectious diarrhea influences the microbiological investigation of the disease, and is best elucidated through prospective studies. We undertook such a study in a Nordic country. Patients of all age groups who had acute diarrhea were recruited prospectively from general practice clinics in Iceland. They completed a questionnaire and provided stool samples for the detection of pathogenic viruses, bacteria, and parasites. Of the 464 recruited patients, 211 (45%) had 224 infections. The most common pathogens were calici- and rotaviruses (23% and 18% of 224 infections, respectively), Campylobacter jejuni (17%), Cryptosporidium species (12%), and Salmonella serotypes (10%). Other agents found were Giardia lamblia, astro- and adenoviruses, and Yersinia enterocolitica. Viral pathogens were associated with vomiting, illness for ≤7 days, and younger age groups, while bacterial pathogens were associated with fever, rectal pain, and local or foreign travel, and parasitic pathogens with illness for >7 days. Detection rates for viral infections in the elderly and for Cryptosporidium species were higher than expected. Our study indicates the existence of regional differences in pathogen prevalence that should be taken into account when implementing guidelines for stool testing in patients with acute diarrheal disease.

Surveillance of influenza in Iceland during the 2009 pandemic.

In a pandemic setting, surveillance is essential to monitor the spread of the disease and assess its impact. Appropriate mitigation and healthcare preparedness strategies depend on fast and accurate epidemic surveillance data. During the 2009 influenza A(H1N1) pandemic, rapid improvements in influenza surveillance were made in Iceland. Here, we describe the improvements made in influenza surveillance during the pandemic , which could also be of great value in outbreaks caused by other pathogens. Following the raised level of pandemic influenza alert in April 2009, influenza surveillance was intensified. A comprehensive automatic surveillance system for influenza-like illness was developed, surveillance of influenza-related deaths was established and laboratory surveillance for influenza was strengthened. School absenteeism reports were also collected and compared with results from the automatic surveillance system. The first case of 2009 pandemic influenza A(H1N1) was diagnosed in Iceland in May 2009, but sustained community transmission was not confirmed until mid-August. The pandemic virus circulated during the summer and early autumn before an abrupt increase in the number of cases was observed in October. There were large outbreaks in elementary schools for children aged 6­15 years throughout the country that peaked in late October. School absenteeism reports from all elementary schools in Iceland gave a similar epidemiological curve as that from data from the healthcare system. Estimates of the proportion of the population infected with the pandemic virus ranged from 10% to 22%. This study shows how the sudden need for improved surveillance in the pandemic led to rapid improvements in data collection in Iceland. This reporting system will be improved upon and expanded to include other notifiable diseases, to ensure accurate and timely collection of epidemiological data.