April showers bring May nymph ticks

We are all anticipating better weather with the coming April showers, and as the rhyme goes, they bring May flowers, but it also brings hungry nymph ticks.

It is useful to have some knowledge of the tick lifecycle. The black legged tick, Ixodes scapularisis, is a three-host tick with each mobile stage feeding on a different host animal, and humans can be one of them.

I feel with climate change there has also been change with the lifecycle of ticks. Typically they can have a two to three year life cycle. Ixodes scapularis is a three-host tick going from egg, larva, nymph and then to adult starting the cycle all over.

Let us start with the adult tick which molted from the nymph and is now out questing for a blood meal and a mate to begin the new cycle of ticks. The adult stage of the tick usually becomes active in October and can remain active throughout the winter whenever temperatures are above 4 degrees Celsius.

The adult females feed for several days while the male will feed only sparingly. The female will drop off into the leaf litter where she will later lay her eggs then die while the male will drop off and die. Beginning in May the engorged adult females will typically lay between 1,000-3,000 eggs at the site where they detached from their hosts. This could be in your own backyard when you note the number of deer in town.

In June and July the eggs that were deposited earlier in the spring hatch into tiny six-legged larvae. The peak larval activity occurs in August. The larvae attach and feed on a wide range of mammals and birds, primarily on white-footed mice. The engorged larvae will then drop to the ground where they will molt and overwinter.

In March of the following year, the eight-legged nymphs will appear and be questing for their next blood meal. Their highest activity can be in May into June declining into October. It was in April of 1997 when we had relatively warm temperatures and I remember removing what seemed like hundreds of nymph ticks from a cat. This was when awareness of Lyme and co-infections was beginning. It is thought that the ticks at this stage and next are quite likely to be carrying disease so please be aware.

The nymph will then drop to the ground where they will molt into the adult stage. The adults will tend to become active in October and the cycle continues for the next crop of eggs that will ripen and be laid in May.

It is important to be aware and know ticks are a year-round problem with some periods of higher risk. Risk is risk no matter how small the risk is it is still a risk. Human exposure to black legged ticks tends to be highest during the summer months when nymph activity is high coinciding with increased outdoor human activity. Fall into the winter months the adult ticks are out so the need to be aware is still there. People tend to be more concerned about their pets than themselves but remember you too are at risk just like your fur family member.

According to the Rankin notes, Nova Scotia reported the highest incidence of Lyme in Canada in 2016 at 34.4 per 100,000 population, which is 12.7 times the national average. I feel certain the numbers today are much higher. Know what you need to do to remain safe and if you have the misfortune of being bitten do not take it lightly. Seek knowledgeable help. Education is key!

Brenda Sterling-Goodwin

New Glasgow