Yes they can be. Even in [location] mosquitoes can carry and transmit several diseases, including:West Nile virus – an infectious disease whose symptoms include fever, skin rash, body aches, and swollen lymph glands.Zika virus – an RNA virus that causes a rash, itching all over, muscle pain, red eyes, joint pain, fever, and a headache.Malaria – a disease caused by a parasite that invades red blood cells and brings on fever, chills, sweating, fatigue, nausea and vomiting, and sometimes jaundice.