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Abstract: The potential was modelled of molecular rapid diagnostic tests (RDTs) that target agents of sexually transmitted diseases (STDs) to contribute to a reduction in the exposure risk for sexually active populations who prefer condom‐free high‐risk contacts. The biostatistical approach is exemplified by considering the use of a PCR‐based RDT for Chlamydia trachomatis and Neisseria gonorrhoeae in a population of German men having sex with men. We modelled the exposure risk as risk of sexual contact with individuals infected by a STD in spite of multiple RDTs having been conducted to identify STDs that could lead to avoidance of an infectious sexual contact. The risk for a given specific disease is influenced by the diagnostic accuracy of all diagnostic tests conducted. The simulation showed a reduction in exposure risk through conducting the selected PCR‐based RDT as a strategy to prevent infections with C. trachomatis and N. gonorrhoeae in comparison with unprotected sexual contact of >97% for C. trachomatis and ≥96% for N. gonorrhoeae. Reliable knowledge of the performance characteristics of the diagnostic tests applied is essential for a thorough risk assessment based on such diagnostic approaches. Significance and Impact of the Study: A low‐threshold use of molecular rapid diagnostic tests in settings where risky sexual activity is undertaken with deliberate non‐use of condoms is modelled. Such an approach might contribute to a considerable reduction in the exposure risk if positively tested individuals are excluded from unprotected sexual intercourse. Protective effects are influenced by the prevalence of the disease and the performance characteristics of the applied tests. Precise knowledge of the performance characteristics of the test assays employed are prerequisites of a reliable risk assessment. The modelling approach is of particular use for preventive health experts. [ABSTRACT FROM AUTHOR]

The study was performed to compare real-time PCR after nucleic acid extraction directly from stool samples as well as from samples stored and transported on Whatman papers or flocked swabs at ambient temperature in the tropics. In addition, the possible suitability for a clear determination of likely aetiological relevance of PCR-based pathogen detections based on cycle threshold (Ct) values was assessed. From 632 Tanzanian children <5 years of age with and without gastrointestinal symptoms, 466 samples were subjected to nucleic acid extraction and real-time PCR for gastrointestinal viral, bacterial and protozoan pathogens. Equal or even higher frequencies of pathogen detections from Whatman papers or flocked swabs were achieved compared with nucleic acid extraction directly from stool samples. Comparison of the Ct values showed no significant difference according to the nucleic acid extraction strategy. Also, the Ct values did not allow a decision whether a detected pathogen was associated with gastrointestinal symptoms., (© 2021 The Authors. Letters in Applied Microbiology published by John Wiley & Sons Ltd on behalf of Society for Applied Microbiology.)

Objectives: Success of methicillin-resistant Staphylococcus aureus (MRSA) decolonization procedures is usually verified by control swabs of the colonized body region. This prospective controlled study compared a single-day regimen with a well-established 3-day scheme for noninferiority and adherence to the testing scheme., Methods: Two sampling schemes for screening MRSA patients of a single study cohort at a German tertiary-care hospital 2 days after decolonization were compared regarding their ability to identify MRSA colonization in throat or nose. In each patient, three nose and three throat swabs were taken at 3- to 4-hour intervals during screening day 1, and in the same patients once daily on days 1, 2 and 3. Swabs were analysed using chromogenic agar and broth enrichment. The study aimed to investigate whether the single-day swabbing scheme is not inferior to the 3-day scheme with a 15% noninferiority margin., Results: One hundred sixty patients were included, comprising 105 and 101 patients with results on all three swabs for decolonization screening of the nose and throat, respectively. Noninferiority of the single-day swabbing scheme was confirmed for both pharyngeal and nasal swabs, with 91.8% and 89% agreement, respectively. The absolute difference of positivity rates between the swabbing regimens was 0.025 (-0.082, 0.131) for the nose and 0.006 (-0.102, 0.114) (95% confidence interval) for the pharynx as calculated with McNemar's test for matched or paired data. Compliance with the single-day scheme was better, with 12% lacking second-day swabs and 27% lacking third-day swabs from the nostrils., Conclusions: The better adherence to the single-day screening scheme with noninferiority suggests its implementation as the new gold standard., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Apart from sporadic exported cases, the occurrence of Ebola, Marburg and Lassa virus diseases is limited to the African continent. Crimean-Congo Hemorrhagic Fever occurs in Southeastern Europe but, so far, not in Germany. Other hemorrhagic fever disease-viruses occur in distinct regions in South America. Pulmonary plague is the bacterial infectious disease with the most contagious and lethal course and it is endemic to Madagascar and East Africa, but also occurs in other countries (e.g. India, USA). Monkey pox epidemics have occurred in remote areas of the Congo Basin. Such outbreaks could potentially become more common with the discontinuation of the cross-protective smallpox vaccination. The Severe Acute Respiratory Syndrome (SARS) that emerged in 2002/2003 is another pathogen with significant epidemic potential. Typical for these diseases is a natural circulation between reservoir animals in remote areas. Sporadic transmission to humans can occur through contact with an infected animal. Subsequent human-to-human transmission can lead to epidemics, such as the current outbreak of Ebola virus disease in West Africa.

Diagnostic misidentifications of commensalic Haemophilus haemolyticus as pathogenic Haemophilus influenzae are frequent. This pilot study evaluates whether isolations of H. haemolyticus are frequent enough in Germany to cause a relevant diagnostic problem, considering the fact that even H. influenzae is a mere colonizer in about 30% of isolations. In microbiological laboratories of two hospitals located in Northern and Southern Germany, the distribution of Haemophilus spp. was analyzed during a six-month-period. Site of infection, sex, and age of the patients was taken into consideration. A total of 77 Haemophilus spp. isolates was acquired and discriminated on species level, comprising: 48 H. influenzae, 25 Haemophilus parainfluenzae, 3 H. haemolyticus, and 1 Haemophilus parahaemolyticus. The proportion of H. haemolyticus was calculated to range between 1.2% and 16.2 % within the 95% confidence limits. Commensalic Haemophilus spp. were isolated from oropharynx-associated sites only. H. influenzae, in contrast, was detected in clinically relevant materials like lower respiratory materials and conjunctiva swabs. Altogether, there was a low proportion of clinical H. haemolyticus isolates. Accordingly, the problem of unnecessary antibiotic therapies due to misidentifications of H. haemolyticus as H. influenzae is quantitatively negligible compared with the risk of confusing H. influenzae colonizations with infections.

Objective: The aim of the current study was to extrapolate incidences for respiratory tract infections (RTI) using referral data from a local hospital in Ghana weighted by the individual likelihood of a hospital visit., Methods: Diagnoses from children visiting a rural hospital in Ghana during August 2007 to September 2008 were recorded. A logistic regression model, based on a population study conducted within the hospital catchment area, was used to calculate the individual probability of clinic attendance and to extrapolate the number of recorded cases. Cumulative incidences for children living in the hospital catchment area were estimated., Results: Upper RTI was the most common respiratory diagnosis, with an extrapolated incidence of 17481 cases per 100000 per year, followed by pneumonia with an incidence of 2496 per 100 000 per year. All diseases analyzed were most common in the first year of life., Conclusions: In general the study results are in line with comparable studies. Several methodological issues biasing the results in different directions were identified. For example, opportunistic infections that are more often observed in hospital attendees are likely to be overestimated. However, the applied approach presents a tool for areas where disease monitoring systems are not established., (Copyright © 2012 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)