Communicable Diseases - Lyme Disease

Communicable Disease Prevention and Control

Lyme Disease

Lyme disease is a bacterial infection transmitted to humans by a bite from an infected blacklegged tick. In Nova Scotia, only the blacklegged tick carries the bacteria that causes Lyme disease, and not all blacklegged ticks carry the bacteria.

Ticks attach to the skin and feed on blood. In most cases, a tick carrying the bacteria that can cause Lyme disease must attach and feed for at least 24 hours before the bacteria can be transmitted.

Lyme disease cannot be transmitted by touching, kissing or being near an infected person.

How many reported cases of Lyme disease are there in Nova Scotia?

The most up to date information on the number of Lyme disease cases reported in Nova Scotia can be found in the Annual Notifiable Disease Surveillance Report available at https://novascotia.ca/dhw/populationhealth/

Where are the areas of risk for Lyme disease in Nova Scotia?

Nova Scotia has a suitable climate for tick populations. Blacklegged ticks survive best in areas that provide a moist habitat and are often found in and near wooded or forested areas, shrubs, long grass, leaf litter, urban parks and gardens. Adult blacklegged ticks are most active in the spring and fall. They remain active until the temperature is consistently below 4°C. Larvae and nymphs are most active in the spring and summer.

Black legged ticks are found throughout Nova Scotia and all areas of the province are considered as having some risk of Lyme disease. The following is a Lyme disease estimated risk areas map (and table) that uses historical Lyme disease case data and active and passive tick surveillance data to show Lyme disease risk by county.

The risk area categories are based on historical Lyme disease case data and tick surveillance (active and passive) data.

Although there are areas of the province where the risk of finding blacklegged ticks is higher, there is a chance of finding blacklegged ticks anywhere in the province.

Within all areas of the province, blacklegged ticks are found in long grass, leaf litter, shrubs, woody areas, urban parks and gardens.

Areas of risk County Risk Annapolis Higher Antigonish Higher Cape Breton Higher Colchester Higher Cumberland Higher Digby Higher Guysborough Moderate Halifax Higher Hants Higher Inverness Lower Kings Higher Lunenburg Higher Pictou Higher Queens Higher Richmond Lower Shelburne Higher Victoria Lower Yarmouth Higher

How can you protect yourself from Lyme disease?

Nova Scotians are encouraged to spend time outdoors, be active and remember to protect yourselves against tick bites, which is the best way to prevent Lyme disease.

There are several ways to prevent or reduce contact with ticks when in areas with long grass, shrubs, leaf litter, woods, urban parks and gardens:

Reduce the risk of having a tick bite:

Apply insect repellents containing DEET or Icaridin to exposed skin and clothes. Follow directions on the package carefully. Permethrin treated clothing repels and kills ticks when they come in contact with it and is now registered for use in Canada for those 16 years of age and older.

Wear light colored, long sleeved shirts and pants, closed-toe shoes

Tuck shirts into pants and tuck pant legs into socks

Walk on well-traveled paths, avoiding high grass and vegetation

Reduce ticks around your home:

Keep lawns mowed short

Remove leaf litter

Put playground equipment in sunny, dry places, away from wooded areas, yard edges, and trees

To access more information about simple landscaping techniques to reduce the number of blacklegged ticks around your home, please see the Landscape Management Handbook.

Remove ticks as soon as possible:

Check yourself, your family, and pets after being in grassy or wooded areas

Check clothing and inspect skin including in and around ears, arm pits, inside belly button, groin, around the waist, and especially in hair and scalp area

When possible, take a bath or shower within two hours of being outdoors. This makes it easier to find ticks and washes away unattached ones

Put clean and dry outdoor clothes in a dryer on high heat for at least 10 minutes to kill any remaining ticks

Use clean tweezers to remove ticks as soon as they are found

Carefully grasp tick as close to the skin as possible and pull the tick straight out

Clean the bite area with soap and water or alcohol-based sanitizer

Record the date and location of the tick bite. This information is important to provide your healthcare provider if you start to have symptoms

You can learn some tips for protecting yourself and your family by watching these videos produced by the federal government in English or French, and a children’s video from the BC Centre for Disease Control below.

How can you have the tick identified?

To have a tick identified please visit eTick.ca for more information.

What should you do if you think you have Lyme disease?

Tick bites are often painless, and you may not know that you have been bitten. Symptoms for Lyme disease typically appear 3 to 30 days after you have been bitten and may include any of the following:

Rash (sometimes shaped like a bull’s eye)

Fever

Chills

Headache

Fatigue

Aching muscles and joints

Swollen lymph nodes

More severe symptoms (experienced weeks to months after a tick bite and no antibiotic treatment taken) may include but are not limited to:

Severe headaches

New skin rashes

Facial paralysis (such as Bell’s palsy)

Irregular heart beat

Joint pain

Nervous system disorders (such as dizziness, confusion or inability to think clearly, and memory loss, nerve pain, numbness or tingling in the hands or feet)

If you have recently been in a grassy or wooded area and have symptoms suggestive of Lyme disease, especially if they include a bull’s eye rash, you should seek prompt medical attention.

The following pictures show examples of this rash:





A bulls-eye rash (Erythema migrans) is a typical symptom of Lyme disease.





The rash associated with Lyme disease is not always in the typical bulls-eye shape.

Photos reproduced with permission from Dr. John Aucott, Lyme MD, Lyme Disease Research Foundation

How do you identify a blacklegged tick?

This chart shows what different types of ticks look like, including dog ticks and blacklegged (deer) ticks which look similar and are both present in Nova Scotia. Visit etick.ca for more information on submitting a tick for identification.

The image below shows a comparison between the blacklegged tick and a dog tick.



Top row: nymph, male and female blacklegged ticks. Bottom row: male and female dog ticks. The blacklegged tick does not always have black coloured legs. Dog ticks usually have white or silver coloured spots.

Photo reproduced with permission from the Public Health Agency of Canada

Where can you find more quality information on Lyme disease?

Here are some reliable sites that can help answer your questions:

Are there other tick-borne diseases?

Other bacteria or viruses carried by blacklegged ticks can cause Human Granulocytic Anaplasmosis (HGA), Borrelia miyamotoi, Babesiosis, and Powassan virus disease. These bacteria and viruses have been found infrequently in ticks or small mammals in Nova Scotia and there have been two cases of Human Granulocytic Anaplasmosis in humans. These tick-borne diseases can be prevented by following the same prevention measures as described above for Lyme disease.