Culling and cattle controls influence tuberculosis risk for badgers.
Human and livestock diseases can be difficult to control where infection persists in wildlife populations. In Britain, European badgers (Meles meles) are implicated in transmitting Mycobacterium bovis, the causative agent of bovine tuberculosis (TB), to cattle. Badger culling has therefore been a component of British TB control policy for many years. However, large-scale field trials have recently shown that badger culling has the capacity to cause both increases and decreases in cattle TB incidence. Here, we show that repeated badger culling in the same area is associated with increasing prevalence of M. bovis infection in badgers, especially where landscape features allow badgers from neighboring land to recolonize culled areas. This impact on prevalence in badgers might reduce the beneficial effects of culling on cattle TB incidence, and could contribute to the detrimental effects that have been observed. Additionally, we show that suspension of cattle TB controls during a nationwide epidemic of foot and mouth disease, which substantially delayed removal of TB-affected cattle, was associated with a widespread increase in the prevalence of M. bovis infection in badgers. This pattern suggests that infection may be transmitted from cattle to badgers, as well as vice versa. Clearly, disease control measures aimed at either host species may have unintended consequences for transmission, both within and between species. Our findings highlight the need for policymakers to consider multiple transmission routes when managing multihost pathogens.
Woodroffe
Rosie
R
Department of Wildlife, Fish, and Conservation Biology, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA. rwoodroffe@ucdavis.edu
Donnelly
Christl A
CA
Jenkins
Helen E
HE
Johnston
W Thomas
WT
Cox
David R
DR
Bourne
F John
FJ
Cheeseman
Chris L
CL
Delahay
Richard J
RJ
Clifton-Hadley
Richard S
RS
Gettinby
George
G
Gilks
Peter
P
Hewinson
R Glyn
RG
McInerney
John P
JP
Morrison
W Ivan
WI
D000818:Animals; D002417:Cattle; D004196:Disease Outbreaks; D005536:Foot-and-Mouth Disease / Q000453:epidemiology; D006801:Humans; D016015:Logistic Models; D045969:Mustelidae / Q000382:microbiology*; D009163:Mycobacterium bovis / Q000302:isolation & purification; D015995:Prevalence; D012307:Risk Factors; D012703:Serotyping; D014380:Tuberculosis, Bovine / Q000453:epidemiology*