BOSTON (CBS) – Two more people have come down with mosquito-borne illnesses in Massachusetts.

Health officials confirmed additional human cases of Eastern Equine Encephalitis and West Nile Virus on Thursday.

A Plymouth county resident in his 60s is currently hospitalized with EEE. He’s the fourth person in the state infected with the illness this year.

A Hampden county resident in his 50s was hospitalized and released after becoming the 14th confirmed case of West Nile Virus this year in the state.

“Today’s announcement is yet another serious reminder that the threat of mosquito-borne illness is still with us, and will remain so until we see the first hard overnight frost,” said DPH State Epidemiologist Dr. Al DeMaria. “People need to continue to use insect repellant, cover up exposed skin, and avoid being outdoors at dusk and after nightfall when mosquitoes are at their most active.”

Initial symptoms of EEE are fever (often 103º to 106ºF), stiff neck, headache, and lack of energy, and in severe cases can progress to confusion, disorientation, and coma. EEE is a serious disease in all ages and can even cause death.

WNV symptoms tend to include fever and flu-like illness. In rare cases, more severe illness can occur.