title: Climate variability and the outbreaks of cholera in Zanzibar, East Africa: a time series analysis.
abstract: Global cholera incidence is increasing, particularly in sub-Saharan Africa. We examined the impact of climate and ocean environmental variability on cholera outbreaks, and developed a forecasting model for outbreaks in Zanzibar. Routine cholera surveillance reports between 1997 and 2006 were correlated with remotely and locally sensed environmental data. A seasonal autoregressive integrated moving average (SARIMA) model determined the impact of climate and environmental variability on cholera. The SARIMA model shows temporal clustering of cholera. A 1°C increase in temperature at 4 months lag resulted in a 2-fold increase of cholera cases, and an increase of 200 mm of rainfall at 2 months lag resulted in a 1.6-fold increase of cholera cases. Temperature and rainfall interaction yielded a significantly positive association (P < 0.04) with cholera at a 1-month lag. These results may be applied to forecast cholera outbreaks, and guide public health resources in controlling cholera in Zanzibar.
authors.affiliation: International Vaccine Institute, SNU Research Park, Seoul, Korea. rita_reyburn@hotmail.com
authors.forename: Rita
authors.initials: R
authors.lastname: Reyburn
authors.forename: Deok Ryun
authors.initials: DR
authors.lastname: Kim
authors.forename: Michael
authors.initials: M
authors.lastname: Emch
authors.forename: Ahmed
authors.initials: A
authors.lastname: Khatib
authors.forename: Lorenz
authors.initials: L
authors.lastname: von Seidlein
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ali
mesh_terms: D000351:Africa, Eastern; D002771:Cholera / Q000453:epidemiology* / Q000635:transmission; D002980:Climate; D004196:Disease Outbreaks / Q000706:statistics & numerical data*; D004784:Environmental Monitoring; D062665:Epidemiological Monitoring; D005544:Forecasting; D006801:Humans; D015994:Incidence; D015233:Models, Statistical; D009792:Oceans and Seas; D011159:Population Surveillance; D012044:Regression Analysis; D012307:Risk Factors; D012621:Seasons; D013636:Tanzania / Q000453:epidemiology; D013696:Temperature