By Anna Perea, Policy and Communications Lead, Bacterial Diseases Branch, Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention
The distribution of ticks and the pathogens they can transmit change over time. As a result, the likelihood of people coming in contact with ticks also changes over space and time. Tick surveillance is intended to monitor changes in the distribution, abundance, and infection rates in ticks that can affect human health.
Data from tick surveillance can provide actionable, evidence-based information to clinicians, the public, and policy-makers regarding when and where people are at risk for exposure to ticks and tickborne pathogens. Additionally, the data can be useful for explaining or predicting trends in human illness.
For example, the expanding range of I. scapularis helps to explain the increasing incidence and geographic range of Lyme and other I. scapularis-associated diseases.
Similarly, data on the density of host-seeking nymphs that are infected with Borrelia burgdorferi (the bacteria that cause Lyme disease) in the eastern United States helps to explain why Lyme disease is most common in the upper Midwest, Northeast and Mid-Atlantic compared with the southeastern United States.
Finally, tick surveillance data can provide information on risk of exposure to agents of tick-borne diseases that are not nationally notifiable, such as B. miyamotoi.
Numbers of Tickborne Disease Cases are Increasing
In 2017, state and local health departments reported a record number of cases of tickborne disease to CDC. Cases of Lyme disease, anaplasmosis/ehrlichiosis, spotted fever rickettsiosis (including Rocky Mountain spotted fever), babesiosis, tularemia, and Powassan virus disease all increased—from 48,610 cases in 2016 to 59,349 cases in 2017. These 2017 data capture only a fraction of the number of people with tickborne illnesses. Under-reporting of all tickborne diseases is common, so the number of people actually infected is much higher.
Personal Prevention Steps Can Reduce Tick Bites
People can reduce their chances of being bitten by a tick by taking the following steps:
- Use Environmental Protection Agency (EPA)-registered insect repellents containing DEET, picaridin, IR3535, Oil of Lemon Eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone. Always follow product instructions.
- Treat clothing and gear with products containing 0.5% permethrin. Permethrin can be used to treat boots, clothing and camping gear, and it remains protective through several washings. Alternatively, you can buy permethrin-treated clothing and gear.
- Check your body and clothing for ticks upon return from potentially tick-infested areas, including your own backyard. Use a hand-held or full-length mirror to view all parts of your body. Place tick-infested clothes in a dryer on high heat for at least 10 minutes to kill ticks on dry clothing after you come indoors.
- Shower soon after being outdoors. Showering within two hours of coming indoors has been shown to reduce your risk of getting Lyme disease and may be effective in reducing the risk of other tickborne diseases. Showering may help wash off unattached ticks and is a good time to do a tick check.
Tickborne Disease Toolkits
As tick season unfolds, CDC’s Division of Vector-borne Diseases is launching two new tickborne disease toolkits on NACCHO’s Toolbox to provide some relief to local health departments that are seeing increasing numbers of ticks and tickborne diseases.
The first toolkit contains something for everyone:
- The public can learn what steps to take after a tick bite;
- Healthcare providers can learn what to do when a patient arrives with an attached tick, including options for tick bite prophylaxis; and
- Health department and vector control officials can benefit from prepared slide sets on tickborne disease prevention and Lyme disease surveillance in low incidence states.
Access the Lyme Disease Toolkit in NACCHO’s Toolbox here. A free MyNACCHO account is required to download the tools.
The second toolkit (coming soon!) contains information regarding tick surveillance:
- Tick surveillance overview slide set
- Ixodes scapularis surveillance guidance
- Ixodes pacificus surveillance guidance
In addition to toolkit materials, CDC offers many other tick-related resources: