A virus stirring worry globally reached the Omaha area Thursday, with two cases of the Zika virus reported, one in Douglas County and one in Sarpy. Health authorities confirmed the virus in two women in their 20s who had recently traveled to Zika-affected nations. • Also, a person in Texas was found to have contracted the disease sexually this week, a revelation that has organizations responding with changes in protocols and advice. The American Red Cross, for instance, sent a recommendation this week on blood transfusions. The Centers for Disease Control and Prevention expects to change its recommendations soon. • The World Health Organization on Monday officially called Zika a "public health emergency of international concern." • The primarily mosquito-borne virus has infected hundreds of thousands of people in South America. And in Brazil, unusually large numbers of cases of microcephaly — babies born with small heads and brain damage — are suspected of being linked to the virus. • What do you need to know about Zika?

Q: What is the Zika virus?

A: It's a disease spread mainly by two kinds of mosquitoes. It typically causes mild fever, rash, red eyes and muscle or joint pain.

Q: Is it deadly?

A: Only about one in five infected people develops symptoms, which are usually mild. It appears that rare victims can suffer serious neurological and autoimmune problems.

Q: So why the alarm?

A: Last fall Brazilian authorities established a tie between the Zika virus and increasing cases of microcephaly in newborns. Health officials are still investigating the link. Microcephaly is a serious birth defect of the brain in which the baby's head is much smaller than normal and there is brain damage.

Q: This situation, then, isn't overblown?

A: The World Health Organization, or WHO, called the level of alarm "extremely high." It cited four reasons: the possible association with birth defects and neurological problems; the potential for further global spread; the lack of immunity in newly affected areas; and the absence of vaccines, treatments and rapid tests.

"Do I believe we should be concerned? Damned right I do," said Beth Conover, genetic counselor at the University of Nebraska Medical Center's Munroe Meyer Institute. National Institutes of Health leadership said a major outbreak in the United States is unlikely, though, because of the limited range of the mosquito species that transmit the virus and U.S. housing conditions.

Q: How has the picture changed this week?

A: Texas health officials said a person there had been infected after having sex with a sick person who had returned from Venezuela. The case intensified concerns and highlighted the unknowns about Zika.

Brazilian health authorities on Thursday confirmed a Zika case contracted through a blood transfusion from a donor who had been infected, Reuters reported.

And on Thursday, the Nebraska Department of Health and Human Services reported two cases in the Omaha area, the first cases in Nebraska.

The American Red Cross this week advised blood donors who have traveled to the Caribbean, Mexico or Central or South America to defer blood donations for 28 days after returning. British health officials already had recommended that men wear condoms for 28 days after returning from an affected area if they are sexually active.

Dr. Renuga Vivekanandan, an infectious disease physician at Creighton University Medical Center, said in an email: "I think with the new information coming out about possible link to sexual transmission, condoms should be used to prevent transmission."

The CDC this week added Jamaica in the Caribbean and Tonga in the South Pacific to the growing list of affected places.

Q: Where is this virus?

A: For years it was found in African and Asian areas near the equator, but countries and territories with Zika virus transmission now include Brazil, Mexico, the Dominican Republic, Guatemala, Haiti, Puerto Rico and many other nations in South and Central America and the Caribbean.

Q: Have there been U.S. cases?

A: Nebraska has reported two cases, which did not originate in the state. Texas health officials said this week that a person had been infected after having sex with a sick person who had returned from South America. Also, in mid-January, a baby born in Hawaii with microcephaly had been infected with the Zika virus. The baby's mother had lived for a time in Brazil last year. There also have been more than 30 people infected with the virus in at least 12 states and Washington, D.C. The cases, confirmed by lab tests, involved patients who had returned to the United States after traveling to an affected region.

Q: How did the Zika virus reach Nebraska?

A: Both women diagnosed, neither one of whom was hospitalized, had recently traveled to Zika-affected countries.

"Seeing a travel-related case of Zika in Nebraska is new but not unexpected. We were aware of confirmed cases among travelers returning to America from affected areas," said Dr. Tom Safranek, state epidemiologist for DHHS. "It's very possible that we could see more travel-related cases here."

Q: Can the Zika virus be transmitted in ways besides mosquito bites, such as sexually or through blood transfusions?

A. Although officials have said it's not clear, the Texas case involved a person who had been infected with the Zika virus after having sex with an ill person who had returned from Venezuela. Concern also has grown that it can be transmitted through blood transfusions.

Q: Do all mosquitoes carry the Zika virus?

A: It appears that two species carry it. One, Aedes aegypti, is a tropical or subtropical mosquito and appears to be the main culprit. The other, Aedes albopictus, can survive in cooler regions and has been found occasionally in Nebraska and Iowa. Aedes, the WHO says, is a weak flyer but conceivably could be accidentally transported by humans in a car or plane and, perhaps, reproduce in a new area.

Q: What's the cure for the Zika virus?

A: There is no cure, and there is no vaccine. A patient with the Zika virus would be treated with supportive care, such as fluids, rest and pain-killing medications.

Q: Should people travel to Mexico, Central America and South America? What about the Caribbean?

A: The CDC recommends that pregnant women avoid traveling to areas affected by the virus. And women of childbearing ages should visit an affected country only if they diligently use birth control. Among the affected areas in the Caribbean, according to the CDC, are Barbados, Curacao, the Dominican Republic, Puerto Rico, St. Martin and the U.S. Virgin Islands.

Q: What if a pregnant woman recently visited an affected region?

A: Those women should consult a doctor. They may well be asked to take a blood test or get an ultrasound scan.

Q: If you plan to go to an affected area, what precautions should you take?

A: It would be wise to go to a travel clinic, of which the metro area has many, including Dr. Rudolf Kotula's clinic at Methodist Physicians Clinic-Regency, 10060 Regency Circle. Travel clinics have vaccinations (there isn't one for the Zika virus, unfortunately) and information about travel to other nations. A complete list of travel clinics may be acquired from the Douglas County Health Department at douglascountyhealth.com/ services-a-clinics or by calling 402-444-7214, but make it clear that you want the list and not just a recommendation.

Q: What other precautions should be taken when going to an affected nation?

A: Use mosquito repellents containing DEET, wear clothing with the chemical permethrin on it, wear long sleeves and long pants, sleep in a place with good screens on windows and doors and with mosquito netting over you when you sleep.

Q: Is there anything else people should know?

A: "I think they should stay tuned," Kotula said. "They should definitely watch the news, watch for CDC updates. The CDC's watching this very carefully."

Commenting is limited to Omaha World-Herald subscribers. To sign up, click here.

If you're already a subscriber and need to activate your access or log in, click here.

(0) comments

Welcome to the discussion.

Please keep it clean, turn off CAPS LOCK and don't threaten anyone. Be truthful, nice and proactive. And share with us - we love to hear eyewitness accounts.

You must be a digital subscriber to view this article.