National Institute for Public Health and the Environment Public Health added value of GIS/spatial analysis for some infectious diseases. Wilfrid van Pelt, Agnetha Hofhuis, Ingrid Friesema, Jan van de Kassteele and many many others 1.Simple type of clustering in space and time implemented in 1999 with an internet interface, of 1000 salmonella types for weekly signaling and retrospective inspection. 2.Simple ecologic analysis of Lyme disease among NL general practices (1995, 2001 en 2006). 3.Provisional Bayesian analysis of regional densities of cattle, pigs and poultry and the occurrence of patients with STEC ( ). Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Course avian influenza epidemic, 2003 poultryfarms, contaminated, culled Thanks to Michiel van Boven Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Rubella notifications by 4 digit postal code The Netherlands, –

National Institute for Public Health and the Environment MMR-1 coverage by municipality The Netherlands, 2004

National Institute for Public Health and the Environment Votes for SGP party by municipality National Elections, The Netherlands, 2003 Percentage of those allowed to vote Thanks to Susan Hahne

National Institute for Public Health and the Environment Outbreak detection by searching for clusters in region & time for Salmonella

National Institute for Public Health and the Environment Intranet Catalogue / Atlas since Mai 1998 human/ animal/ food/ environment All sero and phagetypes Resistance Actual trends, Early Warning, GIS-clusters Each week backcalculated starting in 1984 > Tables and Figures Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Explosions of S. Typhimurium ft 20 Early-Warning application

National Institute for Public Health and the Environment 1st step signal verification: region Silver wedding: Case-control study rPHA Coburgerham, salting process insufficient

National Institute for Public Health and the Environment 1st step signalverification: region-crossing Place, Age, Gender

National Institute for Public Health and the Environment 1st step signalverification: precedent No cause found: RIVM trawling questionnair, too late Animal Health Service, no clou in region

National Institute for Public Health and the Environment Say CHEESE

National Institute for Public Health and the Environment Explosion of Salmonella Typhimurium DT7 cases In January 2006 up to April 2007 an explosion of S.T. DT7 infections occurred, resulting in an extra 297 lab- confirmed cases of salmonellosis. (tip of the Iceberg). Labconfirmed: 297 cases Hospitalized: cases Death (<2jr): Symptomatic Infected General population General Practices Laboratories Hospital † Doctor visits: +/- 650 General Population: +/ GE-cases COI: € 0.6 milj DALY: 54 Schattingen!! Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment 1 jan 2006 half mei 2006 april 2007 Automatische geografische outbreak detectie Kaas affaire Twente Salmonella Typhimurium Ft561

National Institute for Public Health and the Environment Automated geographic outbreak detection Kaas affaire Twente Salmonella Typhimurium Ft561 Januari to half mei 2006 half mai to end 2006

National Institute for Public Health and the Environment Not automated, by hand for publication, looks better Kaas affaire Twente Salmonella Typhimurium Ft561/DT7 januari-december 2006 Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Lyme disease in the Netherlands Agnetha Hofhuis & Wilfrid van Pelt and many others Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Lyme disease in Europe is caused by the Borrelia burgdorferi sensu lato group; B. burgdorferi sensu stricto, B. afzelii, B. garinii Transmission of Lyme disease Transmission by the sheep tick (Ixodes ricinus). Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Lyme disease  Early local infection: erythema migrans (EM) % of B. burgdorferi infections  Early disseminated infection: manifestations in nervous system, skin, joints and heart  Chronic Lyme borreliosis… Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment  retrospective studies among general practitioners (GP’s) ?Incidence of tick bites and erythema migrans ?Geographical distribution in the Netherlands ?Ecological risk factors for tick bites and erythema migrans  retrospective analysis of hospital admissions for Lyme disease ?Occurrence of hospital admissions for Lyme disease ?Seasonal and annual trends in hospital admissions for Lyme disease  collecting ticks in 4 different biotopes ?Density of ticks & infection rate of ticks with Borrelia ?Seasonal & annual trends Studies on Lyme disease in the Netherlands Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment All (± 8.000) general practitioners (GP’s) in 1995, 2002 & 2006 received pre-coded questionnaire about previous year 1. How many patients with tick bites have you seen? 2. How many erythema migrans case-patients have you seen? 3. How many people are included in your practice population? Retrospective GP-study  postal questionnaire Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment  Response, coverage: 88% in % in % in 2005  Tick bite consultations: 1994    EM consultations: 1994   Retrospective GP-study  results Incidence of EM & tick bites per inhabitants

National Institute for Public Health and the Environment

National Institute for Public Health and the Environment Information on risk factors per municipality Roe deer Rabbits Horses Sheep & goats Cattle Woods Degree of urbanization Tourist nights per year Precipitation Parks & public gardens Sandy soil Uncultivated wet soil Uncultivated dry soil Dunes Retrospective GP-study  ecological risk factors Risk analysis for GP-studies of 1994, 2001 & 2005 together: Poisson regression: (offset: city population)  city repeated measure  year “confounder”  no random (un)structered effects, sofar  no Bayesian smoothing, sofar Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Retrospective GP-study  ecological risk factors Risk factors for tick bites  area with sandy soil  mean precipitation  density of roe deer  rural areas (  houses/ km 2 )  tourist areas  cattle / km 2  rabbits / km 2 Risk factors for erythema migrans  area covered with woods  area with sandy soil  mean precipitation  roe deer / km 2  rural area (  houses/ km 2 )  tourist areas Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Geographical distribution of STEC in the Netherlands Wilfrid van Pelt,Loes Bertens, Ingrid Friesema, Jan van de Kassteele (spatial statistician) Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Known, mentioned riskfactors:  Consumption raw milk/cheese (16%)  Contact farmanimal (21%)  Person-to-person transmission (18%)  Consumption ready-to-eat vegetables (28%) Most important reservoir:  Dairy cattle and veals Acute gastroenteritis with Complications  HUS (15%) and Hospital-uptake (41%), accent 0-4 year olds Generalities STEC-O157 infections Provisionary analysis: Spatial relation Cattle density and STEC incidence Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment STEC season in Veals (1 st ), 1-2 weeks later in Humans and Dairy cattle Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment Average ( ) densities of farm animals / km 2 Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment RRP2.5P97.5 (Intercept)0,60,40,8 Cattle: 1000/km 2 6,41,045,2 Pig: 1000/km 2 1,00,71,4 Poultry:1000/km 2 1,00,91,0 Age 0-44,53,45,9 Age 5-91,61,22,1 Age ,50,40,7 Age 50+1,0 Males1,0 Females1,31,01,6 Neighbour matrix of 496 communities WinBUGS model called from R using R2WinBUGS library Model results Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment STEC cases Incidence / [0,1.62] (1.62,4.7] (4.7,7.34] (7.34,11.1] (11.1,16.8] (16.8,22.4] (22.4,31.6] STEC-O157 in NL (2.4 / 10 6 inhabitants; / yr.; N=400) Bayesian “smoothed” version (SMR) Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment STEC-O157 model: Structured and unstructured random effects (residuals) Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.

National Institute for Public Health and the Environment  Web-based GIS-tool for questioning both numerators ( disease, risk factor ) and denominators (underlying population size) : Physicians (EU wide): practice size (denominator), number of Lyme consults (numerator) Children DayCare Centres (NL): weekly reporting children at risk (denominator) and absenteism infectious diseases (numerator)  Immediately mapping and feeding back the rates to GP or DCC, regional PH-body (GGD) and national PH-body (RIVM) Accurate incidence figures for regional comparison and analysis of regional risk factors  Condition: Small, fast web-based application ignoring the artistic selfrespect of GIS developers GIS wishes Hotel Mitland, 5 mrt 2009EUROHEIS2 GIS workshop, Wilfrid van Pelt et al.