Letters to the Editor
In Reply
Point prevalence surveys enable the recording of healthcare-associated infections in the entire hospital with comparatively low effort. Patients are observed only once with regard to the studied outcome. Other types of data collection, which require repeated or continuous monitoring, potentially yield more precise results but translate into a notably higher workload, which makes the viability in the context of a survey such as ours seem questionable.
Infection rates determined by point prevalence surveys can be converted into estimated incidence rates, which usually requires information on the average length of hospital stay and duration of the infectious episode (1). In the European point prevalence survey in 2022 and 2023, in which Germany participated in the spring of 2022, no data were collected on the duration of the episodes of infection (2). The average length of hospital stay was determined on the basis of aggregated data from the participating hospitals on the number of inpatient treatment cases and the number of inpatient days.
We did not record disease diagnostic codes and therefore cannot draw any conclusions regarding this. The collected data, however, enabled us to reconstruct for inhouse healthcare-associated infections the temporal lag between hospital admission and the start of the infection. For the prevalence survey in 2022, the median lag was 10 days (data made available by the author), which indicates that especially long-term inpatients were affected by healthcare-associated infections.
For this reason, we can assume that the observed reduction in the median length of hospital stay from 6.3 days to 5.7 days between 2016 and 2022 affected the determined prevalence of healthcare-associated infections to a low degree, as shorter inpatient stays may possibly be explained with earlier discharges of uncomplicated cases at low risk of healthcare-associated infection. This interpretation is, however, based on speculative assumptions, as the survey did not collect the necessary data.
DOI: 10.3238/arztebl.m2024.0129
On behalf of the authors
PD Dr. med. Seven Johannes Sam Aghdassi
Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin
Institut für Hygiene und Umweltmedizin
seven-johannes-sam.aghdassi@charite.de
Conflict of interest statement
This project was financially supported by the German Federal Ministry of Health (Bundesministerium für Gesundheit) (Grant No. ZMI5–2522PAT004). The grant was awarded to the Institute of Hygiene and Environmental Medicine (Institut für Hygiene und Umweltmedizin), Charité Berlin, and not to an individual person. The authors declare that no conflict of interests exists.
| 1. | Rhame FS, Sudderth WD: Incidence and prevalence as used in the analysis of the occurrence of nosocomial infections. Am J Epidemiol 1981; 113: 1–11 CrossRef MEDLINE |
| 2. | European Centre for Disease Prevention and Control: Point prevalence survey of healthcare-associated infections and antimicrobial use in European acute care hospitals—protocol version 6.1. www.ecdc.europa.eu/sites/default/files/documents/antimicrobial-use-healthcare-associated-infections-point-prevalence-survey-version6–1.pdf (last accessed on 11 June 2024). |
| 3. | Aghdassi SJS, Hansen S, Peña Diaz LA, et al.: Healthcare-associated infections and the use of antibiotics in German hospitals—results of the point prevalence survey of 2022 and comparison with earlier findings. Dtsch Arztebl Int 2024; 121: 277–83 CrossRef |
