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Working outdoors can mean contact with ticks or mosquitos almost anywhere in the world. While these insects may play a crucial role in the ecosystem, they can often feel like a nuisance when we encounter them. Most people have probably been bitten by one or the other; at best, these bites remain in the nuisance category, at worst, they can result in the transmission of disease and may even result in death.

As outdoor work picks up in the northern hemisphere, it is important to consider these little creatures as you develop your job safety analysis (JSA) or activity hazard analysis (AHA). Here’s a little refresher on ticks and mosquitoes!

Different species of ticks and mosquitoes are native to different parts of the world, however, with global travel and other factors, many mosquito- and tick-borne (“vector-borne”) diseases are also traveling. Some of these diseases include malaria, dengue, West Nile fever, Zika virus fever (all mosquito-borne), Lyme disease, and Rocky Mountain spotted fever (both tick-borne), all of which have been found in the US.

In 2018, the US CDC recorded 47,743 tick-borne disease cases and 5,847 mosquito-borne disease cases, with tick-borne disease cases found in every US state except for Hawaii, and mosquito-borne disease cases found in every US state and territory (https://www.cdc.gov/ncezid/dvbd/vital-signs/index.html).

Many of our health and safety programs remind us that, “Everyone should return home safely at the end of the day;” it’s important to remind our teams to keep vigilant about this outdoor work hazard!

Ticks transfer to people by climbing up vegetation and attaching as the person’s pants leg brushes it; they do not jump as is commonly thought. As you prepare your job safety analysis or activity hazard analysis form for work outside, some questions to consider:

1. Will any team member be working in the vicinity of shrubs, grasses, or other vegetation?
2. How tall is the vegetation?
3. Is it possible to remove, trim, or cut back the vegetation before the project? (Do we have a JSA for vegetation removal?)
4. How many hours will we be working in this area?
5. What is the expected temperature and humidity for the day?

Next, determine your control measures, or how you will protect yourself and other workers. Not many of us are fond of chemicals, but if your life depends on it, are you willing to use it? That may sound dramatic, but remember, many mosquito- and tick-borne diseases are potentially fatal. Not every bite will incur disease, but every bite that incurs disease may be irreversible or fatal. The CDC recommends using an EPA-registered repellent, and the EPA offers a web-based tool to help you decide which repellant may be right for your job (https://www.epa.gov/insect-repellents/find-repellent-right-you#search%20tool).

Questions to consider as you document your control measures on your job safety worksheet or activity hazard analysis form:

1. Is it possible to keep my body fully covered with a long-sleeved shirt and long pants that are tucked into socks and/or taped at the ankles?
2. If it will be hot and/or humid, can heat relief measures be established so that workers can continue to wear long sleeved and panted clothing? (For instance, permanent or temporary shaded areas, frequent breaks, ice water, hats, etc.?)
3. Is it possible to wear light colored clothing to both protect from heat, and easily be able to identify any insects on the clothing?
4. Is it possible to spray clothing with permethrin or another heavy-duty repellant?
5. Is it possible to spray exposed skin, as well as skin immediately near clothing openings, with repellant? How often will mosquito and/or tick repellant need to be applied?
6. Do we have a procedure for conducting thorough tick checks and insect bite checks on each worker?
7. How often will tick checks and insect bite checks be performed on each worker?
8. Knowing that tick checks may not be 100% effective, do we have protocols to prevent potentially “contaminated” clothing from contact with “clean” surfaces, either as a decontamination zone at the work site, or as a decontamination protocol upon arrival at individual workers’ homes? How will potentially “contaminated” clothing be handled to prevent the spread of ticks?
9. Have all workers been instructed on how to properly conduct a thorough personal tick check at home (using a mirror as necessary)?

During a tick check, if ticks are found on clothing or skin but have not yet bitten, they can be brushed off. Ticks that have bitten and are starting to engorge should be pulled off as soon as possible. According to the US CDC, most ticks must be attached for 36-48 hours before Lyme disease can be transmitted. In the US, Lyme disease is most often transmitted during spring and summer by ticks in the immature nymph stage, which can be less than 2 mm long – making them difficult to see and reminding us that tick checks truly are important (https://www.cdc.gov/lyme/transmission/index.html)!

If a tick has already bitten the worker and is starting to engorge, it is important that the job safety analysis or activity hazard analysis form, or other site procedures, provide clear instruction on what to do. And it is important that this document be onsite, accessible to workers and presented in the language used by the workers.

For ticks:

1. Has each worker been instructed on proper removal of ticks?
2. Do our site emergency or personal kits contain tweezers and containers for tick removal?
3. Do the kits contain alcohol swabs and pens to swab and mark the bite location?
4. Does our company have a policy for taking an affected employee for medical attention, to take the tick to a lab for testing, or for monitoring the bite site and the employee for signs or symptoms of tick-borne disease, which may take up to a couple weeks (or longer) to manifest?

For general bites:

1. Do our site emergency or personal kits contain anti-itch, anti-sting, or other topical anti-inflammatory treatments?
2. Does our company have a policy for taking an affected employee for medical attention, to mark and monitor the site of the bite area, or for monitoring the bite site and the employee for signs or symptoms of vector-borne disease?

While mosquitoes can be easily swatted, ticks are more difficult to remove. The CDC offers instructions on proper tick removal (https://www.cdc.gov/ticks/removing_a_tick.html):

1. Use fine-tipped tweezers to grasp the tick as close to the skin’s surface as possible.
2. Pull upward with steady, even pressure. Don’t twist or jerk the tick; this can cause the mouth-parts to break off and remain in the skin. If this happens, remove the mouth-parts with tweezers. If you are unable to remove the mouth easily with clean tweezers, leave it alone and let the skin heal.
3. After removing the tick, thoroughly clean the bite area and your hands with rubbing alcohol or soap and water.
4. Never crush a tick with your fingers. Dispose of a live tick by putting it in alcohol, placing it in a sealed bag/container, wrapping it tightly in tape, or flushing it down the toilet.

Note – It is considered “better” to allow the tick mouth part to break off in the skin than to use detergents, Vaseline, or matches to kill or distract the tick. In general, tick mouth parts will work their way out on their own, whereas use of detergents, Vaseline, or matches may startle or kill the tick, and may cause it to insert more of its fluids, including the disease agent, into the wound.

As you prepare your next job safety analysis or activity hazard analysis for outdoor work, ticks and mosquitoes may be an important part of your hazard assessment. Implementing a few simple measures can make a huge difference, and help “everyone return home safely at the end of the day!”

Learn more about what’s going on with vector-borne diseases in the US, including new research as well as how officials are looking to protect public health at: The National Association of County and City Health Officials (NACCHO) and the US CDC’s Division of Vector-Borne Diseases (DVBD).

For CDC information on 2004-2018 vector-borne diseases and an interactive map with specific statistics for each US State and Territory, visit https://www.cdc.gov/ncezid/dvbd/vital-signs/index.html.