Dr. David Strong, acting medical health officer for the south zone, says a southern Alberta woman under the age of 65 has a less-serious non-neurological case of the virus and is expected to recover.
Strong wouldn't give any details about the woman or where she was living, but said Tuesday that she had not travelled outside of Alberta.
"The risk is throughout the province, more so in the south, but it's throughout the province, so the same messaging is there regardless," said Strong, who is urging the public to take precautions to avoid mosquito bites.
Strong said a cool summer in 2011 probably contributed to a lack of West Nile cases. But high temperatures combined with a wet spring have made conditions ideal this year.
The mosquitoes start breeding in June, said Strong, but West Nile cases at this time of year aren't unusual.
"As the summer progresses, the risk goes up in July, August and basically until the first freeze, so it depends on how warm September is going to be as to how long the risk is going to be present."
As of Aug. 11, 34 human cases of West Nile virus had been reported in Canada compared to 102 cases in 2011.