Human alveolar echinococcosis after fox population increase, Switzerland.
We analyzed databases spanning 50 years, which included retrospective alveolar echinococcosis (AE) case finding studies and databases of the 3 major centers for treatment of AE in Switzerland. A total of 494 cases were recorded. Annual incidence of AE per 100,000 population increased from 0.12-0.15 during 1956-1992 and a mean of 0.10 during 1993-2000 to a mean of 0.26 during 2001-2005. Because the clinical stage of the disease did not change between observation periods, this increase cannot be explained by improved diagnosis. Swiss hunting statistics suggested that the fox population increased 4-fold from 1980 through 1995 and has persisted at these higher levels. Because the period between infection and development of clinical disease is long, the increase in the fox population and high Echinococcus multilocularis prevalence rates in foxes in rural and urban areas may have resulted in an emerging epidemic of AE 10-15 years later.
Schweiger
Alexander
A
Institute of Parasitology, University of Zurich, Zurich, Switzerland.
Ammann
Rudolf W
RW
Candinas
Daniel
D
Clavien
Pierre-Alain
PA
Eckert
Johannes
J
Gottstein
Bruno
B
Halkic
Nerman
N
Muellhaupt
Beat
B
Prinz
Bettina Mareike
BM
Reichen
Juerg
J
Tarr
Philip E
PE
Torgerson
Paul R
PR
Deplazes
Peter
P
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002648:Child; D004444:Echinococcosis, Hepatic / Q000453:epidemiology* / Q000635:transmission; D048210:Echinococcus multilocularis / Q000472:pathogenicity; D005589:Foxes / Q000469:parasitology*; D006790:Host-Parasite Interactions; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D012424:Rural Population; D013557:Switzerland / Q000453:epidemiology; D014505:Urban Population; D015047:Zoonoses