Credit: Stewart Gould (WA Today)

Following the announcement of an outbreak of dengue in the north Queensland city last week, a third Townsville resident is believed to have contracted the virus.

According to Queensland Health, it is still awaiting test results on the third suspected dengue fever case in the city, after positive confirmation of the two people who contracted the virus last week.

The latest suspected dengue fever case is the second from the suburb of North Ward, while the other reported case was from Deeragun.

The cases do not seem to be connected and the origin of the outbreak is still unknown, say health authorities.

The dengue outbreak was announced just last week, a month after the city was declared dengue-free from last December's outbreak.

A spokesman of the Dengue Action Response Teams said they are still performing yard inspections and setting traps to eradicate dengue mosquitoes in the city.