Region prepares for buggy summer

By Aly Beach/The Oshawa Express

With the warm summer months upon us, things are about to get a bit buggy, and the Durham Region Health Department is hoping to stay on top of some of the region’s more infectious critters.

Now underway, Durham Region has officially started its mosquito and tick surveillance projects to help monitor the spread of West Nile Virus (WNV) and Lyme disease.

According to the Public Health Agency of Canada, 155 human cases of WNV were reported in Ontario during the 2017 mosquito season, which is more than triple the 44 cases the year before. Durham Region had three human cases in 2017.

For Lyme disease, 40 cases were confirmed in Durham Region with eight more probable cases in 2017. This is a jump from 16 confirmed cases and eight probable cases in 2016.

“And that’s increased dramatically over the previous year, the human cases more than doubled between 2015 and 2017 and I’m expecting another increase this year,” says Durham Region senior health inspector Toni Moran, “I think we’ve seen this across Ontario and across Canada. It’s definitely becoming quite a problem.”

 

WNV is a vector-borne disease spread from birds to mosquitoes to humans. Only mosquitoes can spread the disease, as it cannot be spread from bird to human or human to human. Lyme disease is spread by blacklegged ticks.

To monitor mosquitoes, the region tests adult mosquitoes, mosquito larva and receives medical reports from doctors who have been testing for WNV.

Surveillance areas include standing water sites such as storm water management ponds and roadside ditches. If there is a high amount of mosquito larva in a site, they hire a contractor who administers a low toxicity larvicide. When a human has contracted the disease, it is reported to the Durham Region.

To identify and test blacklegged ticks by “drag sampling”, the process involves dragging a white flannel cloth over and around plants where ticks could be present. The ticks are then sent off to be identified for type and tested for the bacteria that causes Lyme disease. Residents and medical professionals can also submit ticks for testing, something that is becoming more common as awareness for Lyme disease rises.

“I’ve had a record number of ticks submitted this year so far,” says Moran, expecting the number to grow even further throughout the rest of the season and next year.

Around 70 to 80 per cent of infected people do not show symptoms of WNV. If symptoms do occur, they appear within two to 15 days after initial infection. In the case of Lyme disease, symptoms can appear within one to two weeks after a tick bite.

Mild symptoms of WNV include headache, body aches, joint pain, vomiting, diarrhea, and rash. More severe symptoms are severe headache, high fever, stiff neck, nausea, vomiting, trouble swallowing, drowsiness and confusion.

Symptoms for Lyme disease include fever, headache, muscle and joint pain, fatigue and a red rash resembling a bull’s eye target. Symptoms may go away temporarily, but they will often come back more severe.

Mosquitoes lay their eggs in standing water, so residents are asked to help reduce breeding sites by chlorinating or covering rain barrels with mosquito screening, drain water from pools and any other source of standing water such as bird paths or planters, checking that roof gutters are cleared and draining properly, cleaning and maintaining pools and outdoor hot tubs, removing unused tires and making sure drainage ditches are not backed up.

To decrease the risk of getting Lyme disease, residents should take precautions when outdoors, particularly in brushy or wooded areas. People should wear long pants and shirts, socks and closed footwear, use an insect repellent that contains DEET, take showers and examine their bodies for ticks after each outing. Tucking pants into socks and wearing light-coloured clothing makes ticks easier to spot. It also advised to put a tick and flea collar on pets, and routinely check them for ticks.

Ticks are becoming more common in Ontario due to climate change, with warmer winters and changes to animal migratory patterns according to Moran.

“Unfortunately, Durham Region seems to be an extremely good area for tick habitats and we are finding increasing numbers of blacklegged ticks in this area,”

Moran predicts that this season is shaping up to be a nasty one for both mosquitoes and ticks. Tick populations are rising, and due to the weather so far this season, mosquitoes could be potent. Mosquitoes thrive in a weather cycle where it rains a lot, creating standing water for them to breed, and is followed by strong heat, so the larva can thrive and be fully grown in a week.