The City of Hamilton is reporting its first human case of West Nile Virus.
The city's risk level has now been moved from low to moderate.
Residents are being reminded to protect themselves against mosquito bites and to remove standing water from private property to prevent mosquito breeding.
While most people infected with WNV will have no symptoms (approximately 80 per cent), others including older adults or those with weakened immune systems may experience West Nile fever (~20 per cent) or they may develop more severe illness including inflammation of the brain or the lining of the brain (~1 per cent).
Symptoms do occur, they appear two to 14 days after being bitten by an infected mosquito.