A few thoughts about Eastern Equine Encephalitis (EEEV) being found in Ottawa DEET: Start getting in the habit of spraying with DEET if you plan to be outside in the evening. We already had West Nile Virus to worry about, if this is becoming endemic to Ontario ...

... (and the case was not a traveler from New England), then that makes it even more important. Personal anecdote: my wife and I got through 2 weeks in South American rainforests (during the Zika virus wave) with not a single mosquito bite, but sprayed DEET at least once daily.