Correspondence
In Reply
The reduction of the prevalence and nosocomial incidence density of MRSA started in the years before the pandemic. Possible reasons for this trend are discussed in our article. Whether pandemic related hygiene measures since 2020 have affected the epidemiology of MRSA is currently not confirmed for Germany. In contrast to the situation in the USA, where during the pandemic years rates of hospital acquired multiresistant pathogens increased, German hospitals did not observe any increase in multiresistant pathogens or nosocomial infections (1, 2). The “number needed to screen” (NNS) is based on the MRSA prevalence at admission. This is influenced by numerous factors—for example preceding antibiotic treatment, the prevailing MRSA risk profile and the existing screening protocol, the number and type of screening departments in the hospital or screening examinations from other hospitals. These factors distort the local admission prevalence and thus the NNS. Other epidemiologic variables too—such as the nosocomial incidence density—cannot be kept at a stable value by applying a previously calculated NNS. Furthermore, for a valid NNS estimate all patients within an institution would have to be screened, which can be done only in the context of an epidemiologic study but not by means of MRSA hospital infection surveillance. The question is, rather, whether screening all patients at admission is necessary or risk adapted screening is sufficient to prevent as many nosocomial MRSA infections as possible. Studies from the UK have shown that general screening is neither effective for controlling MRSA in hospitals nor cost effective (3). The data of our study also support using the approach of risk adapted admission screening.
DOI: 10.3238/arztebl.m2023.0207
On behalf of the authors
PD Dr. med. Miriam Wiese-Posselt, MPH
Charité – Universitätsmedizin Berlin, Institut für Hygiene und Umweltmedizin
Campus Benjamin Franklin, Berlin, miriam.wiese-posselt@charite.de
Conflict of interest statement
The authors of both contributions declare that no conflict of interest exists.
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