title: Significance of major international seaports in the distribution of murine typhus in Taiwan.
abstract: International seaports are hotspots for disease invasion and pathogens can persist in seaports even after ports are abandoned. Transmitted by fleas infected by Rickettsia typhi, murine typhus, a largely neglected and easily misdiagnosed disease, is known to occur primarily in large seaports. However, the significance of seaports in the occurrence of murine typhus has never been validated quantitatively.
  
  
  
  We studied the spatial distribution of murine typhus, a notifiable disease, in Taiwan. We investigated whether risk of infection was correlated with distance to international seaports and a collection of environmental and socioeconomic factors, using a Bayesian negative binomial conditionally autoregressive model, followed with geographically weighted regression. Seaports that are currently in use and those that operated in the 19th century for trade with China, but were later abandoned due to siltation were analyzed. A total of 476 human cases of murine typhus were reported during 2000-2014 in the main island of Taiwan, with spatial clustering in districts in southwest and central-west Taiwan. A higher incidence rate (case/population) was associated with a smaller distance to currently in-use international seaports and lower rainfall and temperature, but was uncorrelated with distance to abandoned ports. Geographically weighted regression revealed a geographic heterogeneity in the importance of distance to in-use seaports near the four international seaports of Taiwan.
  
  
  
  Our study suggests that murine typhus is associated with international seaports, especially for those with large trading volume. Thus, one of the costs of global trade in Taiwan might be elevated risks of murine typhus. Globalization has accelerated the spread of infectious diseases, but the burden of disease varies geographically, with regions surrounding major international seaports warranting particular surveillance.
authors.affiliation: Department of Life Science, National Taiwan Normal University, Taipei, Taiwan.
authors.forename: Chi-Chien
authors.identifier: 0000-0002-1892-6712
authors.initials: CC
authors.lastname: Kuo
authors.affiliation: Geography and Environment, University of Southampton, Southampton, United Kingdom.
authors.forename: Nicola
authors.initials: N
authors.lastname: Wardrop
authors.affiliation: Department of Geography, National Taiwan University, Taipei, Taiwan.
authors.forename: Chung-Te
authors.initials: CT
authors.lastname: Chang
authors.affiliation: Center for Diagnostics and Vaccine Development, Centers for Disease Control, Ministry of Health and Welfare, Taipei, Taiwan.
authors.forename: Hsi-Chieh
authors.initials: HC
authors.lastname: Wang
authors.affiliation: Geography and Environment, University of Southampton, Southampton, United Kingdom.|Faculty of Science and Technology, Lancaster University, Lancaster, United Kingdom.|School of Geography, Archaeology and Palaeoecology, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Atkinson
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002980:Climate; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D018570:Risk Assessment; D062206:Spatial Analysis; D013624:Taiwan / Q000453:epidemiology; D019371:Topography, Medical; D014437:Typhus, Endemic Flea-Borne / Q000453:epidemiology*; D055815:Young Adult