DOVER — The Delaware Division of Public Health announced Friday a fourth Zika case involving a Delaware resident, this time a Kent County man. Like the three previous cases, he acquired the illness from a mosquito bite while traveling abroad.

The Kent Countian traveled abroad in May. The first three cases announced in February and March were New Castle County residents (two women and a man). None are considered infectious if they are bitten by a mosquito that then bites another person; the virus leaves the blood after about a week and all current Delaware cases are two weeks to several months old.

There have been no confirmed cases of transmission by a local mosquito bite anywhere in the continental U.S. Pregnancy is not a factor in any of the four Delaware cases.

While much less common, Zika can be spread by men via sexual activity so Public Health officials recommend condom use for men who have been diagnosed with Zika virus or have symptoms for at least six months after symptoms first appeared.

Public Health also said Zika education materials targeting pregnant women and their male partners will be distributed at Delaware Women, Infants and Children clinics and other locations. Recommended by the Centers for Disease Control and Prevention, the kit contains mosquito repellent, condoms, thermometers and informational brochures. Information can be found at dhss.delaware.gov/dhss/dph/zika.html.

Zika, a generally mild illness, has been linked to serious birth defects in Brazil and other countries and is most often spread by mosquitoes. Transmission can occur from a mother to her fetus. Sexual transmission from male to female has also been confirmed.

About one in five people infected with the virus develop the disease, and most people who are infected do not develop symptoms. The most common symptoms of Zika virus are fever, rash, joint pain, and conjunctivitis (red eyes). Symptoms typically begin two to seven days after being bitten by an infected mosquito.

A total of 109 Delawareans have or will be tested for Zika; 84 of those tested negative. The other 25 test results are still pending. Sixteen of those tested are pregnant.

To report a potential Zika illness or receive further guidance on patient testing, call the Office of Infectious Disease Epidemiology at (302) 744-4990.