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CDC: West Nile Virus in the United States: Guidelines

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CDC: West Nile Virus in the United States: Guidelines Centers for Disease Control and Prevention Division of Vector-Borne Diseases Promote health and quality of life by preventing and controlling vector-borne diseases West Nile Virus in the United States: Guidelines for Surveillance, Prevention, and Control U.S. Department of Health and Human Services Public Health Service Centers for Disease Control and Prevention National Center for Emerging and Zoonotic Infectious Diseases Division of Vector-Borne Diseases Fort Collins, Colorado 4th Revision June 14, 2013 1 TABLE OF CONTENTS FOREWORD .......................................................................................................................................5 INTRODUCTION .................................................................................................................................7 WEST NILE VIRUS EPIDEMIOLOGY AND ECOLOGY ................................................................................................................. 7 LIMITS TO PREDICTION – THE NEED FOR SURVEILLANCE ....................................................................................................... 10 SURVEILLANCE ................................................................................................................................. 11 OBJECTIVES OF WNV SURVEILLANCE ............................................................................................................................... 11 HUMAN SURVEILLANCE ................................................................................................................................................. 12 Routes of Transmission ....................................................................................................................................... 12 Clinical Presentation ........................................................................................................................................... 12 Clinical Evaluation and Diagnosis ....................................................................................................................... 13 Passive Surveillance and Case Investigation ....................................................................................................... 13 Enhanced Surveillance Activities ......................................................................................................................... 14 ENVIRONMENTAL SURVEILLANCE ..................................................................................................................................... 15 Mosquito-Based WNV Surveillance ..................................................................................................................... 15 Specimen Collection and Types of Traps .......................................................................................................................... 16 Specimen Handling and Processing .................................................................................................................................. 17 Mosquito-Based Surveillance Indicators .......................................................................................................................... 18 Use of Mosquito-Based Indicators ................................................................................................................................... 19 Bird-Based WNV Surveillance.............................................................................................................................. 20 Dead Bird Reporting ......................................................................................................................................................... 20 Avian Morbidity/Mortality Testing ................................................................................................................................... 21 Live Bird Serology ............................................................................................................................................................. 22 Horses and Other Vertebrates ............................................................................................................................ 22 Evaluation of Environmental Surveillance Systems ............................................................................................. 23 ARBONET .................................................................................................................................................................. 24 Data Collected ..................................................................................................................................................... 24 Data Transmission .............................................................................................................................................. 25 Dissemination of ArboNET Data ......................................................................................................................... 25 Limitations of ArboNET Data .............................................................................................................................. 25 LABORATORY DIAGNOSIS AND TESTING ........................................................................................... 27 BIOCONTAINMENT - LABORATORY SAFETY ISSUES ............................................................................................................... 27 SHIPPING OF AGENTS .................................................................................................................................................... 27 HUMAN DIAGNOSIS ...................................................................................................................................................... 28 Serology .............................................................................................................................................................. 28 Virus Detection Assays ........................................................................................................................................ 29 NON-HUMAN LABORATORY DIAGNOSIS ............................................................................................................................. 30 Mosquitoes ......................................................................................................................................................... 30 Identification and Pooling ................................................................................................................................................ 30 Homogenizing and Centrifugation.................................................................................................................................... 30 Virus Detection ................................................................................................................................................................. 31 Non-Human Vertebrates ..................................................................................................................................... 31 2 Serology ............................................................................................................................................................................ 31 Virus Detection ................................................................................................................................................................. 32 PREVENTION AND CONTROL ............................................................................................................ 33 INTEGRATED VECTOR MANAGEMENT ............................................................................................................................... 33 Surveillance Programs ......................................................................................................................................... 33 Larval Mosquito Surveillance ........................................................................................................................................... 34 Adult Mosquito Surveillance ............................................................................................................................................ 34 WNV Transmission Activity .............................................................................................................................................. 34 Mosquito Control Activities ................................................................................................................................. 34 Larval Mosquito Control ................................................................................................................................................... 35 Adult Mosquito Control .................................................................................................................................................... 35 Risk and Safety of Vector Control Pesticides and Practices .............................................................................................. 36 Legal Action to Achieve Access or Control ....................................................................................................................... 36 Quality Control ................................................................................................................................................................. 36 Records 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