In search of hidden Q-fever outbreaks: linking syndromic hospital clusters to infected goat farms.
Large Q-fever outbreaks were reported in The Netherlands from May 2007 to 2009, with dairy-goat farms as the putative source. Since Q-fever outbreaks at such farms were first reported in 2005, we explored whether there was evidence of human outbreaks before May 2007. Space-time scan statistics were used to look for clusters of lower-respiratory infections (LRIs), hepatitis, and/or endocarditis in hospitalizations, 2005-2007. We assessed whether these were plausibly caused by Q fever, using patients' age, discharge diagnoses, indications for other causes, and overlap with reported Q fever in goats/humans. For seven detected LRI clusters and one hepatitis cluster, we considered Q fever a plausible cause. One of these clusters reflected the recognized May 2007 outbreak. Real-time syndromic surveillance would have detected four of the other clusters in 2007, one in 2006 and two in 2005, which might have resulted in detection of Q-fever outbreaks up to 2 years earlier.
van den Wijngaard
C C
CC
National Institute for Public Health and the Environment, Bilthoven, The Netherlands. kees.van.den.wijngaard@rivm.nl
Dijkstra
F
F
van Pelt
W
W
van Asten
L
L
Kretzschmar
M
M
Schimmer
B
B
Nagelkerke
N J D
NJ
Vellema
P
P
Donker
G A
GA
Koopmans
M P G
MP
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D015511:Goat Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D006041:Goats; D006761:Hospitals; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011159:Population Surveillance; D011778:Q Fever / Q000453:epidemiology / Q000635:transmission / Q000662:veterinary*; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult; D015047:Zoonoses