title: Investigation of key interventions for shigellosis outbreak control in China.
abstract: Shigellosis is a major public health concern in China, where waterborne disease outbreaks are common. Shigellosis-containing strategies, mostly single or multiple interventions, are implemented by primary-level health departments. Systematic assessment of the effectiveness of these measures is scarce. To estimate the efficacy of commonly used intervention strategies, we developed a Susceptible-Exposed-Infectious/Asymptomatic-Recovered-Water model. No intervention was predicted to result in a total attack rate (TAR) of 90% of the affected population (95% confidence interval [CI]: 86.65-92.80) and duration of outbreak (DO) of 89 days, and the use of single-intervention strategies can be futile or even counter-productive. Prophylactics and water disinfection did not improve TAR or DO. School closure for up to 3 weeks did not help but only increased DO. Isolation alone significantly increased DO. Only antibiotics treatment could shorten the DO to 35 days with TAR unaffected. We observed that these intervention effects were additive when in combined usage under most circumstances. Combined intervention "Isolation+antibiotics+prophylactics+water disinfection" was predicted to result in the lowest TAR (41.9%, 95%CI: 36.97-47.04%) and shortest DO (28 days). Our actual Shigellosis control implementation that also included school closure for 1 week, attained comparable results and the modeling produced an epidemic curve of Shigellosis highly similar to our actual outbreak data. This lends a strong support to the reality of our model that provides a possible reference for public health professionals to evaluate their strategies towards Shigellosis control.
authors.affiliation: Office for Disease Control and Emergency Response, Changsha Center for Disease Control and Prevention, Changsha, The People's Republic of China.
authors.forename: Tianmu
authors.initials: T
authors.lastname: Chen
authors.affiliation: Stanley Ho Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, The People's Republic of China.
authors.forename: Ross Ka-Kit
authors.initials: RK
authors.lastname: Leung
authors.affiliation: School of Public Health, Xiamen University, Xiamen, The People's Republic of China.
authors.forename: Zi
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Office for Disease Control and Emergency Response, Changsha Center for Disease Control and Prevention, Changsha, The People's Republic of China.
authors.forename: Ruchun
authors.initials: R
authors.lastname: Liu
authors.affiliation: Office for Disease Control and Emergency Response, Changsha Center for Disease Control and Prevention, Changsha, The People's Republic of China.
authors.forename: Xixing
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Chinese Field Epidemiology Training Program, Chinese Center for Disease Control and Prevention, Beijing, The People's Republic of China.
authors.forename: Lijie
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000465:Algorithms; D002681:China / Q000453:epidemiology; D003198:Computer Simulation; D004196:Disease Outbreaks; D004405:Dysentery, Bacillary / Q000453:epidemiology* / Q000517:prevention & control*; D061345:Early Medical Intervention; D006801:Humans; D008962:Models, Theoretical; D011159:Population Surveillance; D012621:Seasons
references.citation: Bull World Health Organ. 1999;77(8):651-66
references.pmid: 10516787
references.citation: Science. 2009 Oct 30;326(5953):729-33
references.pmid: 19745114
references.citation: Epidemiol Infect. 2006 Jun;134(3):605-11
references.pmid: 16288683
references.citation: PLoS One. 2012;7(10):e47239
references.pmid: 23071767
references.citation: J Hyg (Lond). 1964 Sep;62:303-11
references.pmid: 14210777
references.citation: J Family Community Med. 1995 Jul;2(2):36-40
references.pmid: 23012224
references.citation: Epidemiol Infect. 1994 Apr;112(2):235-45
references.pmid: 8149998
references.citation: Indian Pediatr. 2012 Apr;49(4):287-90
references.pmid: 21992857
references.citation: BMC Infect Dis. 2012 Dec 12;12:347
references.pmid: 23234356
references.citation: Appl Microbiol. 1974 May;27(5):823-9
references.pmid: 4598219
references.citation: Appl Environ Microbiol. 1993 Feb;59(2):652-4
references.pmid: 8434933
references.citation: Am J Epidemiol. 1986 Aug;124(2):299-305
references.pmid: 3524201
references.citation: CMAJ. 2009 Nov 10;181(10):673-80
references.pmid: 19825923
references.citation: J Clin Microbiol. 2001 Mar;39(3):1048-56
references.pmid: 11230426
references.citation: BMC Public Health. 2011 May 20;11:353
references.pmid: 21599920
references.citation: Bull Math Biol. 2010 Aug;72(6):1506-33
references.pmid: 20143271
references.citation: Science. 2005 Aug 12;309(5737):1083-7
references.pmid: 16079251
references.citation: Emerg Infect Dis. 1999 Sep-Oct;5(5):607-25
references.pmid: 10511517
references.citation: J Food Prot. 2000 May;63(5):568-72
references.pmid: 10826712
references.citation: PLoS One. 2010 Jun 18;5(6):e10911
references.pmid: 20585565
references.citation: J Trop Med Hyg. 1995 Jun;98(3):145-50
references.pmid: 7783269
references.citation: Exp Biol Med (Maywood). 2011 Aug;236(8):955-61
references.pmid: 21727183