The number of probable and confirmed cases of West Nile fever in Andalucía reached 42 on Monday, making it the largest outbreak of the virus ever recorded in the region.
So far two people have died from the virus in the Seville area - an 85-year-old woman and a 77-year-old man.
As of Monday, 18 patients are in hospital, eight of whom are in intensive care.
This outbreak of the virus, which is spread through mosquito bites, has been attributed to the 30 per cent increase in the number of the insects in the wetlands of the Doñana National Park and around the Guadalquivir river near La Puebla and Coria del Río in Seville province.
Around 20 per cent of those infected develop a fever, headache, vomiting, or a rash. Rare complications include encephalitis or meningitis, leading to neck stiffness, confusion, or seizures.