title: Relationship between clinical signs and transmission of an infectious disease and the implications for control.
abstract: Control of many infectious diseases relies on the detection of clinical cases and the isolation, removal, or treatment of cases and their contacts. The success of such "reactive" strategies is influenced by the fraction of transmission occurring before signs appear. We performed experimental studies of foot-and-mouth disease transmission in cattle and estimated this fraction at less than half the value expected from detecting virus in body fluids, the standard proxy measure of infectiousness. This is because the infectious period is shorter (mean 1.7 days) than currently realized, and animals are not infectious until, on average, 0.5 days after clinical signs appear. These results imply that controversial preemptive control measures may be unnecessary; instead, efforts should be directed at early detection of infection and rapid intervention.
authors.affiliation: Institute for Animal Health, Pirbright Laboratory, Ash Road, Woking, Surrey GU24 0NF, UK. bryan.charleston@bbsrc.ac.uk
authors.forename: Bryan
authors.initials: B
authors.lastname: Charleston
authors.forename: Bartlomies M
authors.initials: BM
authors.lastname: Bankowski
authors.forename: Simon
authors.initials: S
authors.lastname: Gubbins
authors.forename: Margo E
authors.initials: ME
authors.lastname: Chase-Topping
authors.forename: David
authors.initials: D
authors.lastname: Schley
authors.forename: Richard
authors.initials: R
authors.lastname: Howey
authors.forename: Paul V
authors.initials: PV
authors.lastname: Barnett
authors.forename: Debi
authors.initials: D
authors.lastname: Gibson
authors.forename: Nicholas D
authors.initials: ND
authors.lastname: Juleff
authors.forename: Mark E J
authors.initials: ME
authors.lastname: Woolhouse
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001499:Bayes Theorem; D002417:Cattle; D002418:Cattle Diseases / Q000517:prevention & control / Q000635:transmission* / Q000821:virology; D003140:Communicable Disease Control; D005536:Foot-and-Mouth Disease / Q000503:physiopathology* / Q000517:prevention & control / Q000635:transmission* / Q000821:virology; D029544:Foot-and-Mouth Disease Virus / Q000276:immunology / Q000302:isolation & purification / Q000502:physiology; D013997:Time Factors; D014766:Viremia / Q000175:diagnosis / Q000662:veterinary; D017735:Virus Latency
chemical_list: D000914:Antibodies, Viral