2008 Lyme Disease Surveillance Results

Prevention is the key to controlling infection with Lyme Disease. The Medical Entomology laboratory coordinates a surveillance project that was designed to inform us of where one might encounter blacklegged ticks (a.k.a. deer ticks) (Ixodes scapularis)in the state of Iowa. These are the ticks that can transmit the bacterium, Borrelia burgdorferi, that causes Lyme Disease. In addition, the project aims to determine if ticks in those regions are infected with the Lyme Disease bacterium, because the risk of contracting Lyme disease is strongly associated with the presence and number of these ticks and the proportion of those that carry B. burgdorferi.
 

LDSP 17 November 
As of November 17th, 2008, 147 blacklegged tick samples have been submitted to the ISU medical entomology laboratory from counties around the state.  The pie charts on the map above indicate the proportion of the three major tick species sent in from each county. Red denotes the blacklegged tick (Ixodes scapularis), yellow - the American dog tick (Dermacentor variabilis) and blue - the lone star tick (Amblyomma americanum). The total number of ticks submitted from each county is indicated by the size of the pie chart.

   

Because they are infected with and transmit the bacterium that causes Lyme disease (Borrelia burgdorferi), black-legged ticks that are submitted are tested for the presence of B. burgdorferi. Positive samples have been identified in 9 counties (shown in grey) thus far in 2008.  

Species

Total

B. burgdorferi +

B. burgdorferi -

Testing pending

I. scapularis

147

25

116

23

A. americanum

283

n/a

n/a

n/a

D. variabilis

295

n/a

n/a

n/a

     
In addition to these ticks, the LDSP has received one Amblyomma maculatum and 13 Rhipicephalus sanguineus, in 2008. 
This very important project is supported by the Iowa Department of Public Health. Tick testing takes place at the University of Iowa Hygienic Lab.  For more information about ticks in Iowa, please see the "Ticks and Tick-borne Diseases in Iowa" pamphlet recently published through University Extension. More information about submitting ticks to this project can be found through this LINK.