A 79-year-old San Diego woman died of West Nile virus three weeks ago, according to health officials. Two other persons have since picked up the disease transmitted by mosquitoes, health officials announced on Wednesday.

The officials did not reveal the identity of the woman. According to them, the woman fell ill in August and died on September 8. After laboratory test, it was found that the cause of her death was West Nile virus. She was the first person in the San Diego region to die of the mosquito-borne disease this year, the health officials added.

The woman’s death was reported three days after her death. Her death case was listed as suspected West Nile virus case by the heath officials. It was the first death case from the virus in the region, but last year, two persons in the area died from the virus.

The health officials said, “Two other cases of people being sickened by the illness were also confirmed by state testing, bringing the total number of confirmed West Nile virus cases in San Diego County to five so far this year”.

This year, environmental health workers found more than 200 hundreds dead birds and about 31 mosquito batches that were tested positive for the West Nile virus. In 2014, only 41 dead birds were found and six mosquito batches were tested positive for the deadly virus.