In June 2005, shortly after outbreaks of Clostridium
-associated diarrhoea (CDAD) caused by PCR ribotype 027 (toxinotype
III) were reported in Britain, several Dutch healthcare institutions reported
outbreaks of CDAD in patients caused by the same organism [1,2].
Surveillance of CDAD
Surveillance of CDAD in the hospitals with an epidemic increase was started.
All institutions that observed a rise in the incidence of CDAD, or cases
with more serious symptoms or lack of response to treatment with metronidazole,
were invited to send in samples to the reference laboratory in Leiden for
typing to detect 027 and send monthly updates on the outbreak situation
to the national Centre for Infectious Disease Control at the RIVM (http://www.rivm.nl/).
So far, type 027 has been found in 15 of 23 participating institutions.
Hospitals without 027 appeared not to have an increased incidence of CDAD.
Further transmission seems to have occurred in only 8 of the 15 institutions
where 027 was found: 7 hospitals and 1 nursing home.
Before the outbreaks, different testing strategies were in place in the
institutions. During outbreaks, hospitals tested all patients with diarrhoea
of unknown cause, all patients developing diarrhoea after a minimum of three
days or all patients from a specific department (eg, geriatrics).
The hospital laboratories used several different assay types: toxin A immunoassays,
toxin A/B immunoassays or cell cytotoxicity assays. Almost all hospitals
started to use a rapid toxin A/B immunoassay during the outbreak. Additionally,
some hospitals have started culturing C. difficile.
The course of the epidemic differed between institutions (Figure). In one
region where three hospitals use a single regional laboratory, the incidence
C. difficile rose in 2004 or earlier. Unfortunately, no samples
from that period were kept for typing. In some other hospitals, a sharp
increase was seen in 2005. Not all patients with 027 had severe infection,
some had mild colitis and were detected because of increased CDAD incidence.
The median age was 74 years, but a wide range was observed: 13% of patients
were under 50 years of age, 17% 50-64 years, 37% 65-79 years, and 35% over
Figure. Monthly incidence of C. difficile-associated
diarrhoea in seven hospitals with transmission of PCR-ribotype 027*.
*The dotted line represents an estimation of the incidence as admission
numbers are not available yet. The ovals indicate the timing of several
measures in the specific hospital, such as contact isolation and restriction
of the use on fluoroquinolones. The rectangle indicates the easing of measure(s).
A number of guidelines for diagnosis and outbreak control of 027 were issued
by a national expert group (in Dutch available at http://www.infectieziekten.info.
These guidelines were produced in July-August 2005 and have been used since
in all institutions, but not all measures have been followed up to the full
extent in each hospital. By the end of 2005, the incidence had decreased
in several institutions. However, the outbreaks are difficult to control:
most hospitals have continued to have new cases for a long time.
It appears that institutions where stricter measures were agreed on had
a sharper decline in CDAD incidence. However, as numbers are small and in
some hospitals guidelines were better complied with than in others, conclusions
can only be drawn cautiously.
The transmission in 2005 to other hospitals not already affected appears
to have been limited. However, to maintain vigilance into the development
of CDAD (027) outbreaks in Dutch health care institutions, this surveillance
will be continued for at least another half year. Updates of the results
will be published on the Centre for Infectious Disease Control website (http://www.rivm.nl/gezondheid/infectieziekten/centrum_izb/).
We would like to acknowledge all medical microbiologists and infection control
professionals for their contribution in the control and surveillance of