Lyme Disease – An Increasing Risk to Fieldworkers

In this article we highlight the transmission routes and symptoms of Lyme disease and look at the options organisation can take to prevent workers from contracting the disease.

Lyme disease is a bacterial infection caused by spirochaete borrelia burgdorferi. It is spread to humans by infected ticks and has become a serious health hazard in northern latitudes. A 2015 study by Johns Hopkins Bloomberg School of Public Health found that Lyme disease costs the U.S. healthcare system between $712 million and $1.3 billion per year.

According to insurers and risk agencies the threat of Lyme disease is rising year on year. This has been attributed to climate change i.e. rising temperatures and the favourable conditions that it creates for the ticks that carry the disease.

we highlight the transmission routes and symptoms of Lyme disease, and look at the options organisation can take to prevent workers from contracting the disease

Transmission

Transmission of the bacterial infection is from animals, to ticks, and on to humans. The bacteria in question are present in the digestive systems of many different animals including:

Ticks are small spider-like insects that feed on the blood of mammals including deer, sheep, dogs, cats, and humans. If a tick bites an animal that has the Lyme disease bacteria they can also become infected with it. The disease-carrying tick can then transfer the bacteria to a human by biting them and feeding on their blood.

The ticks that cause Lyme disease are commonly found in woodland, grassland, and heathland areas. This is because these types of habitats have a high number of tick-carrying animals such as deer, mice, birds, and sheep.

Signs and symptoms

The most common symptom of Lyme disease is an expanding red skin rash that looks similar to a bull’s eye on a dart board. The Erythema Migrans rash will appear from 3 to 30 days following an infected bite. See Fig. 1 below for reference.

If Lyme disease is left untreated the following symptoms may occur:

The symptoms of Lyme disease usually fall into three distinct stages: early stage, mid-stage and late-stage. Workers should only experience symptoms of mid- and late-stage Lyme disease if they are not treated with antibiotics during the initial stage of the condition. This is why checking for and early detection of ticks on skin is key to preventing the disease.  It is worth noting that an employee with Lyme disease cannot spread the disease to co-workers or family through normal social contact.

Why is Lyme disease on the rise?

According to global risk agencies the threat of Lyme Disease appears to be on the rise due to rising global temperatures. This has seen ticks appear in regions not previously associated with Lyme disease.

Due to their breeding patterns, the tick population is highest in late spring and early summer, but adult ticks do last until autumn. According to global risk agencies the threat of Lyme Disease appears to be on the rise due to rising global temperatures. This has seen ticks appear in regions not previously associated with Lyme disease. It has also meant that ticks are more plentiful due to warmer winters which allow for higher rates of survival. As a result Lyme disease and other tick-borne illnesses are on the rise and in newly reported regions.

Ticks carrying Lyme disease are an international risk, and can be found in rural areas in the following countries:

Prevention of tick bites

Currently, there is no vaccine available for Lyme disease. The best way to prevent getting Lyme disease is to be aware when employees are in tick habitat, and take sensible precautions. 

Covering bare skin and using insect repellent containing N,N-Diethyl-meta-toluamide (DEET) such as Jungle Formula Maximum or Pyramid Trek 50 which both contain 50% DEET and are proven repellents offering reliable protection. Even more effective is the treatment of clothing with permethrin sprays such as Pyramid Pyrethrum Fabric Spray or Lifesystems EX4 which are proven to kill ticks in 10-30 seconds after exposure. Shirttails and pant cuffs should be tucked in carefully when entering tall vegetation. OR Bugout Gaiters are pretreated with insect repellent and are particularly useful in preventing ticks and biting insects from entering socks and pants while hiking and walking.

For occupations or tasks that require personnel to remain in long vegetation for sustained periods, companies should investigate insect-repellent clothing for peace-of-mind. Pretreated Craghoppers NosiLife Mens Insect Repellent Travel Trousers and Craghoppers NosiLife Clara Women’s Trousers – SS20 provide permanent protection to field workers and negate the risks of forgetting, losing or running out of insect repellent. For those who wear shorts, DANISH ENDURANCE Insect Shield Outdoor Walking Socks offer insect protection up to knee height. Given the well-documented threat of Lyme disease pretreated outdoor clothing is a prudent investment, and is relatively inexpensive.

Skin inspection and diagnosis

Inspection of skin at the end of each work day for signs of ticks and tick bites is an essential part of a prevention strategy. A recently attached tick will stay on the skin for several days, gorging itself on the hosts blood before dropping off of its own accord. The longer the tick remains attached the higher the risk is of contracting Lyme disease.  Workers should pay particular attention to hidden body places such as the backs of the knees, armpits, the back of the neck, and the groin area. Ticks can be removed from the body using tweezers.

Early detection of bites and symptoms is key to preventing the more debilitating aspects of the disease

Diagnosis of Lyme disease is based on the symptoms, tick exposure, and blood testing. Early detection of bites and symptoms is key to preventing the more debilitating aspects of the disease. The presence of Lyme disease is properly verified via blood testing. Without blood-testing the early stages of the disease are commonly misdiagnosed, under-diagnosed or not diagnosed at all. Mistaken diagnoses can include meningitis, arthritis, heart problems, Bell’s palsy, and stroke.

Antibiotic tablets (oral antibiotics) are recommended for the treatment of early-stage Lyme disease which may appear like a flu. Most workers will require a 2-3 week course of antibiotics. If they are are prescribed antibiotics it is important that they finish the course even if they are feeling better, because this will ensure that all the bacteria are destroyed.

Mid- and late-stage Lyme disease, which can occur between 6-36 months after initial infection, can also be treated with antibiotics. If their symptoms are particularly severe, antibiotic injections (intravenous antibiotics) may be used. Most people with mid- and late-stage Lyme disease will require a prolonged course of antibiotics. Late disseminated Lyme disease can stay with sufferers for years resulting in chronic ailments such as fatigue, brain fog, headaches, and joint pain.

Comment

Lyme disease is a serious 21st century occupational risk that can result in severe and long-lasting symptoms if left untreated. Climate change and rising temperatures are allowing for the proliferation of disease carrying ticks beyond normal latitudes. This means that the disease is on the rise and may be contracted in new locations with each year. To protect field staff the risk of Lyme disease requires formal assessment where outdoor work is being carried out in late spring through to early autumn. Given the life changing effects of Lyme disease careful counter-measures are highly recommended.

Actionable information

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