Spatial, spatio-temporal distribution and temporal trend of Equine Infectious Anemia, Glanders and Rabies in horses in BrazilInfectiousdiseases; Geographicalanalysis; Space-time clusters; Zoonosis; Epidemiologicalsurveillance.
Equineindustry in Brazilis a sector ofgreateconomicand social relevance, generatingaround 16 billion per yearandapproximately 3 million jobs. However, infectiousandcontagiousdiseasessuch as EquineInfectious Anemia (EIA), Glanders, and Rabies cause damage to theproductionchain, in addition to theirzoonoticpotential. To addressthechallengesposedbythesediseases, theNationalProgram for EquineHealth (PNSE) andtheNationalProgram for Rabies Control in Herbivores (PNCRH) wereestablished to ensure animal health in the country. In thiscontext, defininghigh-risktransmissionareasisessential for monitoringtheeffectivenessoftheprogramsanddirectingresources. Thisstudyaimed to mapandidentifyhigh-riskareas for EquineInfectious Anemia (EIA), Glanders, and Rabies in equines in Brazilthroughspatial, space-time, and temporal trendanalysisbetween 2006 and 2023, using data fromthe Animal HealthInformationSystem (SIZ). For EIA, 111,826 cases werereported, withhigherprevalence in theNortheast (39.75%), Central-West (27.56%), andNorth (20.95%) regions. Thestateof Mato Grosso (MT) registeredthehighestnumberof cases (17.02%), while Ceará (CE) presentedthehighestriskofincidence (8,287.84/100,000 equines). High-risk clusters wereidentified in thestatesof Amapá (AP), Pará (PA), Maranhão (MA), Roraima (RR), Tocantins (TO), Piauí (PI), Amazonas (AM), Ceará (CE), Mato Grosso (MT), Rondônia (RO), Rio Grande do Norte (RN), and Pernambuco (PE). Despitetheoveralldecrease in the EIA virusinfection rate in Brazil (AAPC: -8.4; CI: -11.2 to -5.4), theSouthregionshowedanincreasingtrend (AAPC: 6.5; CI: 2.9 to 10.3). RegardingGlanders, 2,654 cases wererecorded, predominantly in theNortheast (52.19%), with Pernambuco (PE) presentingthehighestriskofincidence (342.58/100,000). Primary clusters wereidentified in thestatesof Rio Grande do Norte (RN), Paraíba (PB), Pernambuco (PE), Alagoas (AL), Ceará (CE), and Piauí (PI), whilesecondary clusters wereobserved in Amazonas (AM), Santa Catarina (SC), Rio Grande do Sul (RS), Mato Grosso (MT), Rio de Janeiro (RJ), São Paulo (SP), and Federal District (DF). The temporal analysisindicated general stability in Brazil, butgrowth in theNorth, South, and Central-West regions. For Rabies, 2,170 cases wererecorded, withtheSoutheastregionreportingthehighestnumber (41.66% ofthe cases), followedbythe Central-West (24.47%) andSouth (14.01%) regions. Theriskofincidencewashighest in theSoutheast (45.73/100,000 equines), with São Paulo (SP) (69.97/100,000 equines) and Espírito Santo (ES) (124.68/100,000 equines) standing out. Thespace-time scan analysisidentifiedhigh-risk clusters in São Paulo (SP), Mato Grosso (MT), Espírito Santo (ES), Rio de Janeiro (RJ), and Amazonas (AM). The temporal trendsofincidenceshowed a decrease in Brazil (APC: -3.9%; CI: -6.2 to -1.5), withthehighestreductionobserved in the Central-West region (APC: -8.4%; CI: -14.3 to 2.2). Theresultshighlighttheimportanceofspatial, space-time, and temporal trendanalyses in monitoringinfectiousandcontagiousdiseases, enablingtheidentificationofpriorityareasandsupportingpreventiveandcontrolactions, such as sanitaryregulations, integratedsurveillance, equinemovementcontrol, andinvestments in earlydiagnosisandhealtheducation.