Volume 23, Number 6—June 2017
CME ACTIVITY - Research
Relative Risk for Ehrlichiosis and Lyme Disease in an Area Where Vectors for Both Are Sympatric, New Jersey, USA
Table
Parameters used in relative risk calculations for ehrlichiosis and Lyme disease, by vector, Monmouth County, New Jersey, USA*
Parameter | Ixodes scapularis | Amblyomma americanum | |||
---|---|---|---|---|---|
Relative abundance of each species | CIS = 38.32 |
CAA = 61.68 |
|||
Adults |
Nymphs |
Adults |
Nymphs |
||
Relative abundance of each life stage | CIS. D = 19.96 | CIS. N = 80.04 | CAA. D = 35.34 | CAA. N = 64.66 | |
Infection rates per life stage |
IIS. D = 39.87 |
IIS. N = 23.3 |
IAA. D = 11.7 |
IAA. N = 9.04 |
|
Infection rates, weighted | IIS = 26.60 | IAA = 9.98 |
*Values are in percentages. Relative abundances (denoted by CX) are derived from specimens submitted to the Monmouth County Mosquito Control Division’s tick identification and testing service during peak Lyme disease transmission season (May–August) and during a 10-year period (2006–2015). Infection rates of I. scapularis ticks with Borrelia burgdorferi (IIS) also from passive surveillance program. Infection rates of A. americanum ticks (IAA) encompass both Ehrlichia chaffeensis and E. ewingii (accounting for co-infection).