A Kent County man is the fourth Delaware resident to contract the Zika virus after traveling abroad.

The Delaware Division of Public Health (DPH) today announced the fourth Zika virus case involving a Delaware resident.

Like the three other cases, the person acquired the illness from a mosquito bite while traveling abroad.

The first three cases announced in February and March were New Castle County residents -- two women and a man.

The latest case is a Kent County man who traveled abroad in May.

None of the Delaware residents are considered infectious if they are bitten by a mosquito that then bites another person, according to DPH. 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.

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 more Delawareans have been tested or are in the process of being tested for Zika. According to DPH, 84 of those tested negative. The other 25 test results are still pending, 16 of which are for pregnant women.

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

“We are not surprised at a fourth Delaware case given the amount of global travel these days and we expect more to come,” said DPH Director Dr. Karyl Rattay. “It simply reinforces the message that taking mosquito bite prevention steps while abroad is very important. The illness continues to show no symptoms in the majority of people and symptoms are generally mild for those who do become ill. However, pregnant women and their male partners with a travel history to the countries with Zika should be especially concerned and take precautions because of the potentially very serious birth defects linked to the disease.”

DPH Medical Director Dr. Awele Maduka-Ezeh said, “The U.S. and District of Columbia now have 691 confirmed Zika cases, none of which were local mosquito-borne. That may begin to change if we see more and more cases in the continental U.S., which increases the likelihood of local mosquitoes being infected with the disease. Preventing mosquito bites and using condoms here and abroad remain the best protection.”

WARNINGS FOR WOMEN WHO ARE PREGNANT OR TRYING TO BECOME PREGNANT

While much less common, Zika can also be spread by men via vaginal, anal, and oral sexual activity. DPH continues to recommend condom use for men who have been diagnosed with the Zika virus or have symptoms for at least six months after symptoms first appeared.

DPH recently announced new Zika public education materials targeting pregnant women and their male partners, including offering Zika prevention kits to pregnant women. The kits will be distributed at Delaware Women, Infants and Children (WIC) clinics and other locations. Recommended by the Centers for Disease Control and Prevention (CDC), the kit contains mosquito repellent, condoms, thermometers, and informational brochures.

DPH will also be offering updated information and links to educational materials, which can be found at: dhss.delaware.gov/dhss/dph/zika.html.

Zika outbreaks have been reported in Central and South America and the Caribbean. For an up-to-date list of CDC travel warnings, visit wwwnc.cdc.gov/travel/page/zika-information. Anyone who lives or travels in the impacted areas can be infected.

If you are pregnant, the DPH advises that you postpone travel to the countries where Zika virus transmission is ongoing. If your male sexual partner has traveled to or lives in an area with active Zika virus transmission, condoms should be used for the duration of the pregnancy. Discuss your male partner’s potential exposures and history of Zika-like illness with your doctor.

If you are trying to become pregnant and have been diagnosed with Zika virus or have symptoms of Zika, wait at least eight weeks after symptoms first appeared before trying to conceive, the DPH advised.

Men who have been diagnosed with Zika virus or have symptoms are advised to wait at least six months after symptoms first appeared before having vaginal, oral, or anal unprotected sex.

Men and women who do not have symptoms of Zika but had possible exposure through recent travel or sexual contact should wait at least eight weeks after possible exposure before trying to conceive in order to minimize risk.

If your male partner lives in an area with active Zika transmission but has not developed symptoms, use condoms for vaginal, oral, or anal sex while there is active Zika virus transmission in the area.

If you are pregnant or may become pregnant and must travel to an area with Zika, talk to your doctor first and strictly follow steps to prevent mosquito bites during your trip. If you traveled to an area with active Zika virus transmission up to eight weeks before your pregnancy was confirmed, discuss your travel history with your doctor.

For further information for pregnant women and their male partners, see www.dhss.delaware.gov/dhss/dph/files/zikaflyerforpregnantwomen.pdf.

PREVENTING MOSQUITO BITES

To reduce the risk of mosquito bites, use Environmental Protection Agency (EPA) registered insect repellents; stay in places with air conditioning or that use window or door screens to keep mosquitoes outside; sleep under a mosquito bed net if you are outside and not able to protect yourself from mosquitoes; treat clothing and gear with permethrin available in pharmacies or purchase permethrin-treated items; and wear long-sleeved shirts and long pants.

The Delaware Department of Natural Resources and Environmental Control (DNREC) urges property owners to do their part to remove and reduce mosquito breeding habitats by cleaning debris from clogged rain gutters and emptying water from corrugated downspout extenders; frequently changing water in birdbaths; draining unused swimming pools and kiddie wading pools; and by preventing or draining standing water from outdoor containers such as discarded tires, cans, buckets, flower pot liners, children’s toys, unprotected water cisterns, upright wheelbarrows, uncovered trash cans, upturned trash can lids, open or lidless dumpsters, plugged or undrained boats, sags in tarps covering boats or ATVs, or other water-holding containers.

To learn more about how to reduce mosquitoes around your home, two videos with information about Zika virus and backyard water sanitation tips also are available on DNREC’s YouTube Channel: Zika Virus, Mosquitoes & You, and Mosquito Control & Your Backyard.

For more information about Delaware’s Mosquito Control program, call the field offices or the main Dover office at 302-739-9917, or visit http://de.gov/mosquito.