Historical summaries are provided for horse, human, mosquito and bird positive samples dating back to 1978 and are displayed by year and by parish. 

Note: Not all parishes conduct arbovirus surveillance using sentinel chickens, wild birds, and/or mosquitoes. In parishes that have horse and human cases only, arbovirus transmission between birds and mosquitoes may be occurring naturally but will not be detected due to the lack of surveillance. Also, arbovirus surveillance strategies change periodically, such as whether or not to test mosquito pools. Horse and mosquito information before 1993 is limited and the totals reported in this pages may not accurately reflect arbovirus transmission in those years or parishes.

Please select from the following summaries:

Year by Year historical summaries of horse and human cases

Horse, Human, Bird, and Mosquito by Parish
Acadia Morehouse
Allen Orleans
Ascension Ouachita
Asssumption Plaquemines
Avoyelles Point Coupee
Beauregard Rapides
Bienville Richland
Bossier St. Charles
Caddo St. James
Cameron St. Landry
Calcasieu St. Martin
Claiborne St. Mary
DeSoto St. Tammany
East Baton Rouge Tangipahoa
East Feliciana Terrebonne
Evangeline Union
Iberia Vermilion
Iberville Vernon
Jefferson Washington
Jefferson Davis Webster
Lafayette West Baton Rouge
Lafourche Winn
Livingston

Horse, Human, Bird, and Mosquito by Year
1976 1991
1977 1994
1980 1995
1981 1996
1982 1997
1983 1998
1984 1999
1985 2000
1986 2001
1987 2002