Hamilton confirms 1st human case of West Nile Virus

Hamilton confirms 1st human case of West Nile virus

The virus is now considered high risk by Hamilton Public Health

The City of Hamilton confirmed on Tuesday its first local case of the West Nile Virus (WNV).

The city's medical officer of health has reclassified the WNV risk from moderate to high.

Public health says about 80 per cent of people infected with West Nile virus have no symptoms. Those who do can experience fever, headache, body aches, a mild rash, and swollen lymph glands.

Symptoms can appear two to 14 days after being bitten by an infected mosquito.

In rare cases, the virus can cause more serious illness, including inflammation of the brain or the lining around the brain. About one per cent of people infected develop severe illness.

Older adults and people with weakened immune systems or certain chronic conditions are at greater risk of serious complications.

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Hamilton Public Health has completed its third round of larvicide treatments in city street catch basins, as well as treatments of surface water on public land, to reduce mosquito populations and the risk of the virus.

“It is important to take precautions to avoid illnesses spread by insects including West Nile Virus, Lyme disease and Eastern equine encephalitis,” said Dr. Bart Harvey, associate medical officer of health, in a Tuesday Hamilton Public Health release.

West Nile virus is usually spread when a mosquito bites an infected bird and later bites a person or another animal, according to Health Canada.

In rare cases, it can also spread through blood transfusions, organ, or tissue transplants, pregnancy, breast milk or exposure to infected medical specimens in laboratory settings.

It cannot be spread by touching or kissing someone who has the virus.

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Canadian Blood Services and Héma-Québec test blood donations for West Nile virus to prevent transmission through transfusions.

The risk of West Nile virus and other mosquito-borne illnesses is expected to fall once heavy frost reduces mosquito populations, according to public health.

Hamilton Public Health is encouraging residents to:

Mosquitoes can lay eggs in very shallow standing water, meaning items such as containers and other objects that collect water can become breeding sites.

Public health says residents should seek medical care if they develop symptoms consistent with West Nile virus after being bitten by a mosquito.