The incidence of laboratory-confirmed cases of enteric pathogens in Denmark 2018: a national observational study

BACKGROUND

Only a subset of enteric pathogens is under surveillance in Denmark, and knowledge on the remaining pathogens detected in acute gastroenteritis is limited. Here, we present the one-year incidence of all enteric pathogens diagnosed in Denmark, a high-income country, in 2018 and an overview of diagnostic methods used for detection.

METHODS

All 10 departments of clinical microbiology completed a questionnaire on test methods and provided 2018-data of persons with positive stool samples with Salmonella species, Campylobacter jejuni/coli, Yersinia enterocolitica, Aeromonas species, diarrheagenic Escherichia coli (Enteroinvasive (EIEC), Shiga toxin-producing (STEC), Enterotoxigenic (ETEC), Enteropathogenic (EPEC), and intimin-producing/attaching and effacing (AEEC)), Shigella species., Vibrio cholerae, norovirus, rotavirus, sapovirus, adenovirus, Giardia intestinalis, Cryptosporidium species, and Entamoeba histolytica.

RESULTS

Enteric bacterial infections were diagnosed with an incidence of 229.9 cases/100,000 inhabitants, virus had an incidence of 86/100,000 and enteropathogenic parasites of 12.5/100,000. Viruses constituted more than half of diagnosed enteropathogens for children below 2 years and elderly above 80 years. Diagnostic methods and algorithms differed across the country and in general PCR testing resulted in higher incidences compared to culture (bacteria), antigen-test (viruses), or microscopy (parasites) for most pathogens.

CONCLUSIONS

In Denmark, the majority of detected infections are bacterial with viral agents primarily detected in the extremes of ages and with few intestinal protozoal infections. Incidence rates were affected by age, clinical setting and local test methods with PCR leading to increased detection rates. The latter needs to be taken into account when interpreting epidemiological data across the country.

Opportunistic screening of young men for urogenital Chlamydia trachomatis infection in general practice

Chlamydia trachomatis is a widespread, sexually transmitted infection causing pelvic inflammatory disease, infertility, ectopic pregnancy and chronic pelvic pain among women. Asymptomatic infections among men contribute significantly to maintaining the spread of the infection. In a 1-y intervention study in general practices we aimed to evaluate an opportunistic screening programme targeting 16-25-y-old men. When the young men saw their general practitioner (GP) for the first time during the intervention y, they were offered a test for C. trachomatis based on a first catch urine sample. Main outcome measures were percentage of tested men and prevalence of infection in the intervention practices compared with the test activity in the rest of the county during the intervention y and the y before. GPs in the intervention practices saw 617 (75.6%) of the 814 registered young men during the intervention period. Screening was offered to 300 (48.6%) and 219 (26.9% of the target population) accepted the invitation. The prevalence of infection among screened men was 5.0%. We conclude that opportunistic screening for urogenital C. trachomatis infection in general practice is feasible.

Evaluation of amoxicillin clavulanate twice daily versus thrice daily in the treatment of otitis media in children. Danish-Swedish Study Group

A total of 311 children who had recurrent otitis media or who had experienced failure of initial treatment of acute otitis media with phenoxymethylpenicillin, amoxicillin, ampicillin esters or cefaclor were entered into a single-blind study in two parallel groups in order to compare the clinical efficacy and safety of amoxicillin/clavulanate suspension given b.i.d. or t.i.d. for seven days. The patients were examined prior to the start of treatment, at an early follow-up visit 9 to 12 days after the start of treatment and at a late follow-up visit about three weeks later. Specimens for bacteriological culture were taken from the nasopharynx at entry, at the early follow-up visit, and at the late follow-up visit if there were symptoms of otitis. Both treatment groups showed a similar response, 90% or more of the patients being cured or showing improvement at the time of the early follow-up visit. The initial nasopharyngeal cultures showed growth of Haemophilus influenzae in 53% of the patients, Moraxella catarrhalis in 43% and Streptococcus pneumoniae in 39%. After treatment, cultures showed elimination of the initial pathogens in 30% of patients in both groups and recolonization in 23% in both groups. Haemophilus influenzae was the bacteria most frequently found in the nasopharynx at the first follow-up visit. Adverse effects, which consisted mostly of gastrointestinal and dermatological reactions, tended to be more common in the b.i.d. group but the difference was not statistically significant.