title: Hepatitis-B virus endemicity: heterogeneity, catastrophic dynamics and control.
abstract: Hepatitis-B virus infection is globally ubiquitous, but its distribution is very heterogeneous, with prevalence of serological markers in various nations ranging from less than 1% to more than 90%. We propose an explanation for this diversity using a mathematical model of hepatitis-B virus transmission dynamics that shows, for the first time, 'catastrophic' behavior using realistic epidemiological processes and parameters. Our major conclusion is that the prevalence of infection is largely determined by a feedback mechanism that relates the rate of transmission, average age at infection and age-related probability of developing carriage following infection. Using the model we identify possible, highly non-linear, consequences of chemotherapy and immunization interventions, for which the starting prevalence of carriers is the most influential, predictive quantity. Taken together, our results demand a re-evaluation of public health policy towards hepatitis-B.
authors.affiliation: Ecology and Epidemiology Group, Department of Biological Sciences, University of Warwick, Coventry, UK. graham.medley@warwick.ac.uk
authors.forename: G F
authors.initials: GF
authors.lastname: Medley
authors.forename: N A
authors.initials: NA
authors.lastname: Lindop
authors.forename: W J
authors.initials: WJ
authors.lastname: Edmunds
authors.forename: D J
authors.initials: DJ
authors.lastname: Nokes
mesh_terms: D002353:Carrier State; D006509:Hepatitis B / Q000453:epidemiology* / Q000821:virology; D006801:Humans; D015995:Prevalence