Background The objective of this study was to perform a seroprevalence survey on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among Danish healthcare workers to identify high risk groups. Methods All healthcare workers and administrative personnel at the seven hospitals, pre-hospital services and specialist practitioner clinics in the Central Denmark Region were invited to be tested by a commercial SARS-CoV-2 total antibody enzyme-linked immunosorbent assay (ELISA, Wantai Biological Pharmacy Enterprise Co., Ltd., Beijing, China). Results A total of 25,950 participants were invited. Of these, 17,971 had samples available for SARS-CoV-2 antibody testing. After adjustment for assay sensitivity and specificity, the overall seroprevalence was 3.4% (CI: 2.5%-3.8%). The seroprevalence was higher in the western part of the region than in the eastern part (11.9% vs 1.2%, difference: 10.7 percentage points, CI: 9.5-12.2). In the high prevalence area, the emergency departments had the highest seroprevalence (29.7%), while departments without patients or with limited patient contact had the lowest seroprevalence (2.2%). Among the total 668 seropositive participants, 433 (64.8%) had previously been tested for SARS-CoV-2 RNA, and 50.0% had a positive RT-PCR result. Conclusions We found large differences in the prevalence of SARS-CoV-2 antibodies in staff working in the healthcare sector within a small geographical area of Denmark. Half of all seropositive staff had been tested positive by PCR prior to this survey. This study raises awareness of precautions which should be taken to avoid in-hospital transmission. Regular testing of healthcare workers for SARS-CoV-2 should be considered to identify areas with increased transmission.

Recent studies have suggested that procalcitonin (PCT) is a safe marker for the discrimination between bacterial and viral infection, and that PCT-guided treatment may lead to substantial reductions in antibiotic use. The present objective was to evaluate the effect of a single PCT measurement on antibiotic use in suspected lower respiratory tract infections (LRTIs) in a Danish hospital setting. In a randomized, controlled intervention study, 223 adult patients admitted to the hospital because of suspicion of LRTI were included with 210 patients available for analysis. Patients were randomized to either PCT-guided treatment or standard treatment. Antibiotic treatment duration in the PCT group was based on the serum PCT value at admission. The cut-off point for recommending antibiotic treatment was PCT > or =0.25 microg/L. Physicians could overrule treatment guidelines. The mean duration of hospital stay was 5.9 days in the PCT group vs. 6.7 days in the control group (p 0.22). The mean duration of antibiotic treatment during hospitalization in the PCT group was 5.1 days on average, as compared to 6.8 days in the control group (p 0.007). In a subgroup analysis of chronic obstructive pulmonary disease patients, the mean length of stay was reduced from 7.1 days in the control group to 4.8 days in the PCT group (p 0.009). It was concluded that the determination of a single PCT value at admission in patients with suspected LRTIs can lead to a reduction in the duration of antibiotic treatment by 25% without compromising outcome. No effect on the length of hospital stay was found.

Background The vast majority of patients with peritonsillar abscess (PTA) recover uneventfully on abscess drainage and antibiotic therapy. However, occasionally patient´s condition deteriorates as the infection spread in the upper airway mucosa, through cervical tissues, or hematogenously. The bacterial etiology of PTA is unclarified and the preferred antimicrobial regimen remains controversial. The current narrative review was carried out with an aim to (1) describe the spectrum of complications previously recognized in patients with peritonsillar abscess (PTA), (2) describe the bacterial findings in PTA-associated complications, and (3) describe the time relation between PTA and complications. Methods Systematic searches in the Medline and EMBASE databases were conducted and data on cases with PTA and one or more complications were elicited. Results Seventeen different complications of PTA were reported. The most frequently described complications were descending mediastinitis (n = 113), para- and retropharyngeal abscess (n = 96), necrotizing fasciitis (n = 38), and Lemierre´s syndrome (n = 35). Males constituted 70% of cases and 49% of patients were > 40 years of age. The overall mortality rate was 10%. The most prevalent bacteria were viridans group streptococci (n = 41, 25%), beta-hemolytic streptococci (n = 32, 20%), F. necrophorum (n = 21, 13%), S. aureus (n = 18, 11%), Prevotella species (n = 17, 10%), and Bacteroides species (n = 14, 9%). Simultaneous diagnosis of PTA and complication was more common (59%) than development of complication after PTA treatment (36%) or recognition of complication prior to PTA (6%). Conclusion Clinicians involved in the management of PTA patients should be aware of the wide range of complications, which may arise in association with PTA development. Especially males and patients  > 40 years of age seem to be at an increased risk of complicated disease. In addition to Group A streptococci and F. necrophorum , the current findings suggest that viridans group streptococci, S. aureus , Prevotella , and Bacteroides may also play occasional roles in the development of PTA as well as spread of infection. Complications occasionally develop in PTA patients, who are treated with antibiotics and surgical drainage.

The need for a microbial identification of Streptococcus pneumoniae independent of culture methods has resulted in the introduction of other laboratory principles. The verification of a proper and exclusive gene for the detection of the pneumococcus by nucleic acid-based tests is, however, still unresolved. A previously published lytA-gene-specific real-time PCR method was applied to a panel of bacterial strains to clarify the analytical sensitivity and specificity of a PCR assay targeting this gene. Furthermore, a phylogenetic analysis of published lytA gene sequences was performed to look at gene sequence differences and the theoretical match with the primers and probes. The lytA-gene-specific PCR detected 46/46 S. pneumoniae isolates. All 49 of the non-pneumococcal isolates tested negative, including 22 isolates from the mitis group streptococci. Phylogenetic analysis of 94 sequences of the lytA gene from different strains of S. pneumoniae, Streptococcus mitis and Streptococcus pseudopneumoniae showed that 70/87 S. pneumoniae sequences constituted one cluster and a further six sequences were outside but adjacent to this cluster, all with a complete match with primers and probes. The remaining 11 S. pneumoniae strains could be placed in a different cluster, which also contained the five S. mitis and two S. pseudopneumoniae strains. All strains had no match with primers and probes. The S. pneumoniae strains in the second cluster were all characterized by being bile-insoluble, an infrequent pneumococcal phenotype. Routine laboratories can utilize the additional observation that pneumococci that were negative by the specific PCR also carried the phenotype of bile insolubility, thereby observing the incidence of false-negative results produced by the PCR assay. The real-time PCR targeting the lytA gene thus constitutes a sensitive and specific assay that distinguishes S. pneumoniae from its close relatives in the mitis group.

Objectives: The objective of this study was to perform a large seroprevalence survey on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among Danish healthcare workers to identify high risk groups. Design: Cross-sectional survey. Setting: All healthcare workers and administrative personnel at the seven hospitals, pre-hospital services and specialist practitioner clinics in the Central Denmark Region were invited by e-mail to be tested for antibodies against SARS-CoV-2 by a commercial SARS-CoV-2 total antibody enzyme-linked immunosorbent assay (ELISA, Wantai Biological Pharmacy Enterprise Co., Ltd., Beijing, China). Participants: A total of 25,950 participants were invited. Of these, 17,987 (69%) showed up for blood sampling, and 17,971 had samples available for SARS-CoV-2 antibody testing. Main outcome measures: 1) Prevalence of SARS-CoV-2 antibodies; 2) Risk factors for seropositivity; 3) Association of SARS-CoV-2 RNA and antibodies. Results: After adjustment for assay sensitivity and specificity, the overall seroprevalence was 3.4% (CI: 2.5%-3.8%). The seroprevalence was higher in the western part of the region than in the eastern part (11.9% vs 1.2%, difference: 10.7 percentage points, CI: 9.5-12.2). In the high prevalence area, the emergency departments had the highest seroprevalence (29.7%) while departments without patients or with limited patient contact had the lowest seroprevalence (2.2%). Multivariable logistic regression analysis with age, sex, and profession as the predictors showed that nursing staff, medical doctors, and biomedical laboratory scientists had a higher risk than medical secretaries, who served as reference (OR = 7.3, CI: 3.5-14.9; OR = 4., CI: 1.8-8.9; and OR = 5.0, CI: 2.1-11.6, respectively). Among the total 668 seropositive participants, 433 (64.8%) had previously been tested for SARS-CoV-2 RNA, and 50.0% had a positive RT-PCR result. A total of 98% of individuals who had a previous positive viral RNA test were also found to be seropositive. Conclusions: We found large differences in the prevalence of SARS-CoV-2 antibodies in staff working in the healthcare sector within a small geographical area of Denmark and signs of in-hospital transmission. Half of all seropositive staff had been tested positive by PCR prior to this survey. This study raises awareness of precautions which should be taken to avoid in-hospital transmission. Additionally, regular testing of healthcare workers for SARS-CoV-2 should be considered to identify areas with increased transmission. Trial registration: The study is approved by the Danish Data Protection Agency (1-16-02-207-20).