Heer-Sonderhoff criticized the fact that the baseline totals of intensive care units and surgical wards did not remain the same, but actually increased, over the six-year time period. We therefore redid our calculations, including only the wards/departments that continuously provided data throughout. The results are comparable: the proportion of MRSA among nosocomial S aureus infections fell—still significantly—in our new analysis: from 33% MRSA in 2007 to 27% in 2012 (wound infections from 21% to 16%, sepsis from 37% to 32%, and respiratory tract infections from 37% to 31%).
Heizmann requested for the following parameters to be analyzed in order to explain the regional differences: differences over time in the structure of participants, in the federal states’ population density, in the study methods, and in the ratio of patients to healthcare personnel.
These parameters either did not change or did not affect our results, or they were not retrieved. The composition remained the same over time: university medical centers accounted for 7% in 2007 and 6% in 2012.
Furthermore, our results remained the same when only participating institutions were included that provided continual data. Our study investigated only the proportions of nosocomial MRSA infections; the population density in individual states is of absolutely no relevance in this setting. We did not retrieve the study methods and the ratio of patients to healthcare staff, but we do not believe that they would be so drastically different in different federal states as to provide an explanation for the regional differences. The age dependency ratio (number of patients aged 65 and older/100 patients aged 20–65) was lowest in Berlin in 2008, at 29, although the proportion of MRSA among cases of nosocomial S aureus infection was significantly higher than in other German states. By contrast, the age dependency ratio in Brandenburg was high, at 35, although the proportion of MRSA was significantly lower (1). This cannot be the reason for the regional differences—large regional differences, which have also been described for countries such as the US and Switzerland.
PD Dr. med. Elisabeth Meyer
Klinikhygiene, Klinikum München
Conflict of interest statement
The authors of all contributions declare that no conflict of interest exists.
|1.||Statistisches Bundsamt: www.destatis.de/laenderpyramiden/ Last accessed on 2 July 2014|
|2.||Meyer E, Schröder C, Gastmeier P, Geffers C: The reduction of nosocomial MRSA infection in Germany—an analysis of data from the Hospital Infection Surveillance System (KISS) between 2007 and 2012. Dtsch Arztebl Int 2014; 111: 331–6.|