The current MLVA typing scheme for Enterococcus faecium is less discriminatory than MLST and PFGE for epidemic-virulent, hospital-adapted clonal types

BACKGROUND: MLVA (multiple-locus variable-number tandem repeat analysis) is a reliable typing technique introduced recently to differentiate also isolates of Enterococcus faecium. We used the established VNTR (variable number of tandem repeats) scheme to test its suitability to differentiate 58 E. faecium isolates representing mainly outbreaks and clusters of infections and colonizations among patients from 31 German hospitals. All isolates were vancomycin-resistant (vanA type). Typing results for MLVA are compared with results of macrorestriction analysis in PFGE (pulsed-field gel electrophoresis) and MLST (multi-locus sequence typing). RESULTS: All 51 but one hospital isolates from 1996–2006 were assigned to the clonal complex (CC) of epidemic-virulent, hospital-adapted lineages (MLST CC-17; MLVA CC-1) and differed from isolates of sporadic infections and colonizations (n = 7; 1991–1995) and other non-hospital origins (n = 27). Typing of all 58 hospital VRE revealed MLVA as the least discriminatory method (Simpson's diversity index 0.847) when compared to MLST (0.911) and PFGE (0.976). The two most common MLVA types MT-1 (n = 16) and MT-159 (n = 14) combined isolates of several MLST types including also major epidemic, hospital-adapted, clonal types (MT-1: ST-17, ST-18, ST-280, ST-282; MT-159: ST-78, ST-192, ST-203). These data clearly indicate that non-related E. faecium could possess an identical MLVA type being especially critical when MLVA is used to elucidate supposed outbreaks with E. faecium within a single or among different hospitals. Stability of a given MLVA profile MT-12 (ST-117) during an outbreak over a period of five years was also shown. CONCLUSION: MLVA is a suitable method to assign isolates of E. faecium into distinct clonal complexes. To investigate outbreaks the current MLVA typing scheme for E. faecium does not discriminate enough and cannot be recommended as a standard superior to PFGE

Methicillin-resistant Staphylococcus aureus from infections in horses in Germany are frequent colonizers of veterinarians but rare among MRSA from infections in humans

AbstractA total of 272 methicillin-resistant Staphylococcus aureus (MRSA) from equine infections originating from 17 equine hospitals and 39 veterinary practices in Germany as well as 67 isolates from personnel working at equine clinics were subjected to molecular typing. The majority of isolates from horses was attributed to clonal complex (CC) 398 (82.7%). Within CC398, 66% of isolates belonged to a subpopulation (clade) of CC398, which is associated with equine clinics.MRSA attributed to CC8 (ST254, t009, t036, SCCmecIV; ST8, t064, SCCmecIV) were less frequent (16.5%). Single isolates were attributed to ST1, CC22, ST130, and ST1660. The emergence of MRSA CC22 and ST130 in horses was not reported so far. Nasal MRSA colonization was found in 19.5% of veterinary personnel with occupational exposure to horses. The typing characteristics of these isolates corresponded to isolates from equine infections.Comparing typing characteristics of equine isolates with those of a substantial number of isolates from human infections typed at the German Reference Center for Staphylococci and Enterococci (2006–2014; n=10864) yielded that the proportion of isolates exhibiting characteristics of MRSA from equine medicine is very low (<0.5%). As this low proportion was also found among MRSA originating from nasal screenings of human carriers not suffering from a staphylococcal infection (n=5546) transmission of MRSA from equine clinics to the community seems to be rare so far

How to stop a biological clock: Point of singularity

Many processes in organisms proceed rhythmically. There are, for instance, daily rhythms as adaptations to the 24 hour time structure of the environment, annual rhythms as adaptations to the course of the year, but also shorter rhythms without any correlate to the environment such as the heart beat and respiration. Such rhythms can be stopped by a disturbance by e.g a light pulse given at a certain time point of an oscillation with a special strength. Models show, that the underlying oscillator is brought from a limit cycle into a singular point. Examples for daily rhythms, for an annual rhythm, and for the heart beat are presented, in which the rhythm is stopped. How this property can be used in the praxis is demonstrated by the case of the sudden heart-circulation collaps and in the photoperiodic flower induction of a plant.Viele Vorgänge bei Organismen verlaufen rhythmisch. So gibt es zum Beispiel Tagesrhythmen als Anpassung an die 24 stündige Zeitstruktur der Umwelt, Jahresrhythmen als Anpassung an den Jahreslauf, aber auch kürzere Rhythmen, die keine Korrelate in der Umwelt haben wie der Herzschlag oder die Atmung. Solche Rhythmen können durch Störungen zum Erliegen gebracht werden, zum Beispiel durch einen Lichtpuls, der zu einem ganz bestimmten Zeitpunkt der Schwingung mit einer besonderen Stärke gegeben wird. Modelle zeigen, dass der zugrunde liegende Oszillator von einem Grenzzyklus in einen singulären Punkt gebracht wird. Beispiele für Tagesrhythmen, für einen Jahresrhythmus und für den Herzschlag werden vorgestellt, bei denen der Rhythmus gestoppt wird. Wozu diese Eigenschaft in der Praxis benutzt werden kann, wird am plötzlichen Herz-Kreislauf Kollaps und der photoperiodischen Blühinduktion einer Pflanze gezeigt

Wie man eine biologische Uhr stoppen kann: Singularitätspunkt

Viele Vorgänge bei Organismen verlaufen rhythmisch. So gibt es zum Beispiel Tagesrhythmen als Anpassung an die 24 stündige Zeitstruktur der Umwelt, Jahresrhythmen als Anpassung an den Jahreslauf, aber auch kürzere Rhythmen, die keine Korrelate in der Umwelt haben wie der Herzschlag oder die Atmung. Solche Rhythmen können durch Störungen zum Erliegen gebracht werden, zum Beispiel durch einen Lichtpuls, der zu einem ganz bestimmten Zeitpunkt der Schwingung mit einer besonderen Stärke gegeben wird. Modelle zeigen, dass der zugrunde liegende Oszillator von einem Grenzzyklus in einen singulären Punkt gebracht wird. Beispiele für Tagesrhythmen, für einen Jahresrhythmus und für den Herzschlag werden vorgestellt, bei denen der Rhythmus gestoppt wird. Wozu diese Eigenschaft in der Praxis benutzt werden kann, wird am plötzlichen Herz-Kreislauf Kollaps und der photoperiodischen Blühinduktion einer Pflanze gezeigt

Epidemiology and economic burden of measles, mumps, pertussis, and varicella in Germany: a systematic review

Damm O, Witte J, Wetzka S, et al. Epidemiology and economic burden of measles, mumps, pertussis, and varicella in Germany: a systematic review. INTERNATIONAL JOURNAL OF PUBLIC HEALTH. 2016;61(7):847-860.Despite the availability of vaccines and the existence of public vaccination recommendations, outbreaks of vaccine-preventable childhood diseases still cause public health debate. The objective of this systematic review was to provide an overview of the current epidemiology and economic burden of measles, mumps, pertussis, and varicella in Germany. We systematically reviewed studies published since 2000. The literature search was conducted using PubMed and EMBASE. Also, we used German notification data to give an up-to-date overview of the epidemiology of the four diseases under consideration. Thirty-six studies were included in our review. Results suggest that there is still considerable morbidity due to childhood diseases in Germany. Studies providing cost estimates are scarce. Comparative analyses of different data sources (notification data vs. claims data) revealed a potential underestimation of incidence estimates when using notification data. Furthermore, several studies showed regional differences in incidence of some of the diseases under consideration. Our findings underline the need for improved vaccination and communication strategies targeting all susceptible age and risk groups on a national and local level