Ottawa Public Health
is warning people to protect themselves from mosquito bites after confirming a human case of West Nile virus in the city along with an Eastern Equine Encephalitis virus (EEEV) infection in a horse.
Both diseases spread to humans through mosquito bites. EEEV is less common in humans than West Nile virus, but more serious. An
Ottawa resident died last year
after becoming infected.
Anyone who lives, works or participates in outdoor activities where mosquitoes are present can be at risk,
OPH
is warning.
The case of West Nile virus confirmed this week is the first one in Ottawa this year.
Most people bitten by an infected mosquito do not develop any symptoms, but West Nile can cause serious illness in a small number of cases. About 20 per cent of those infected experience flu-like symptoms, including fever, headache, muscle aches and a rash.
More serious illness, when the disease impacts the central nervous system, occurs in fewer than one per cent of infections, but the risk goes up for older adults, the elderly and people with weakened immune systems.
West Nile virus usually shows up in late summer and early fall. Last year, there were 13 human cases in Ottawa and 87 throughout the province. As of Aug. 20, there have been 11 human cases across Ontario so far this year. That number does not include the Ottawa case.
What is Eastern Equine Encephalitis virus?
Eastern Equine Encephalitis virus (EEEV), also spread by infected mosquitos, is rare in humans, but serious. The Ottawa resident who died of EEEV last year was one of just four human cases ever reported in Ontario. Humans do not get infected from horses or other people, but an infection in a horse indicates infected mosquitoes are present in the city.
EEEV is normally transmitted between wild birds and mosquitos. Occasionally it can infect horses and, in rare cases, humans, through infected mosquito bites. In about 30 per cent of cases, the infection, which can cause a serious neurological disease in humans, is fatal. Half of survivors are left with neurological issues.
There have been no human cases reported this year.
The mosquitoes that transmit West Nile virus live in urbanized areas while those that carry EEEV are usually found close to swampy hardwood forests.
How can residents take precautions to protect themselves from West Nile virus and EEEV?
Ottawa Public Health is recommending people take mosquitoes seriously by following these steps:
- Applying a mosquito repellent containing DEET or icaridin to exposed skin and clothing;
- Wearing light-coloured, tightly woven, loose-fitting clothing, such as long pants, long-sleeved shirts, shoes and socks to protect skin;
- Making sure all windows and doors have screens in good condition;
- Removing any standing water sites around homes including birth baths, toys, buckets and others that retain water;
- Keeping all openings to rain barrels covered.
Find more information at:
ottawapublichealth.ca/en/public-health-topics/west-nile.aspx
