Despite the beginning of mosquito season and rising national concerns over cases of the Zika virus, officials at the Spokane Regional Health District say there is little to no risk of an outbreak of the mosquito-borne disease occurring here. 

The Zika virus is a mosquito-transmitted infection related to dengue, yellow fever, and West Nile virus. For most people, the symptoms are mild and the virus causes no lasting harm. It has been linked, however, to birth defects in developing fetuses. 

Consequently, the Center for Disease Control has issued travel warnings advising pregnant women and those trying to get pregnant to avoid travel to areas where Zika outbreaks have occurred. Although the virus is mainly spread by mosquitoes, cases of sexual transmission also have been reported.

Epidemiologist Anna Halloran works for the Spokane Regional Health District, studying diseases like Zika within populations, analyzing causes in order to treat existing diseases and prevent future outbreaks.

“We have received occasional calls from individuals who are concerned about Zika virus, and while we understand their concerns, the likelihood of an outbreak here is extremely low,” says Halloran. 

The reason for that, she says, is because the Zika virus is spread by infected Aedes species of mosquitos, which aren’t found in the Pacific Northwest. 

“I suppose theoretically an outbreak is possible eventually with climate changes, but currently our climate here doesn’t support them,” she says. “We don’t have as much risk of a local transmission as certain southern or Gulf Coast states.”  

Halloran says that type of mosquito is more common to southern areas with warmer climates, particularly Central and South American countries, parts of Africa, Southeast Asia, and the Pacific islands. 

She says the likelihood of a large-scale outbreak of Zika in the U.S. is also low, mostly because of good mosquito control programs, access to insect repellants, and the availability of air conditioning, which limits mosquitos’ ability to enter indoor locations. 

“Many of the countries experiencing outbreaks have a higher level of poverty, no access to air conditioning, or poor sanitation,” she says. “This mosquito type is aggressive, feeding on multiple people, often in the daytime, and has the ability to breed in very small amounts of standing water.”

As of mid-May, the CDC reported a total of 544 travel-associated cases of Zika virus, in which a traveler has become infected and returned to the U.S.  Of those, two occurred in Washington state. So far, the organization has yet to report any cases of the virus that were acquired in the U.S.  

Since last winter, Halloran says, Spokane County has only tested 11 people for Zika virus, and none have tested positive.

Symptoms of Zika infection typically appear within a few days after a person has been infected. The most common symptoms include fever, rash, joint pain, and red eyes. Halloran says those symptoms are mild for most people and can be mistaken for other viruses, including others that spread through mosquito bites.

 “Eighty percent of people who’ve been infected show either no symptoms or mild enough symptoms that they may not even seek care,” says Halloran. 

She says that’s one reason health officials have turned their attention to warning people who travel frequently, specifically women who are pregnant or trying to get pregnant. 

“We warn travelers because of the likelihood of infection and spreading infection when they return. We warn pregnant women because the virus has been linked to birth defects, specifically microcephaly,” she says. 

Microcephaly is a condition in which a baby’s brain doesn’t develop properly, resulting in a smaller than normal head. Babies with microcephaly can exhibit neurological defects, seizures, impaired intellectual development, and poor motor function.

“The consequences of infection can be really serious in unborn children,” Halloran says. “Microcephaly is the big one, but Zika has also been associated with miscarriage, eye problems, developmental issues, and other poor pregnancy outcomes.” 

Zika also has been linked to Guillain-Barré syndrome, a rare condition in which the immune system attacks the nerves, leading to muscle weakness, possible paralysis, and in some cases death.

“This virus is still being researched, so there are still a lot of things we don’t know yet,” says Halloran. 

She earned her undergraduate degree from the University of Idaho in 2005, and went on to earn her master’s in health and policy administration from Washington State University in 2008. She also received a graduate certificate in Epidemiology of Infectious Diseases from the University of South Florida in 2015. She has worked with the health district for seven years, and has served in her current position for the past two.

For now, she says, the CDC recommends that those traveling to affected countries follow guidelines to avoid mosquito bites and the possibility of transmitting Zika upon their return. The organization advises special precautions for pregnant women or those trying to become pregnant, suggesting that they either postpone travel entirely or speak to their health care provider specifically about Zika risks. 

The CDC advises that among individuals who have been diagnosed with Zika or have symptoms, women should wait at least eight weeks after their symptoms first appear before trying to get pregnant, and men should wait at least six months after their symptoms first appear to have unprotected sex. 

For men and women without symptoms of Zika virus, but who had possible exposure to Zika from recent travel or sexual contact, the CDC recommends health care providers advise their patients to wait at least eight weeks after their possible exposure before trying to get pregnant, in order to minimize risk.

Currently there’s no vaccine to prevent Zika and no medicine designed to treat the virus specifically, only its symptoms. The federal government is in the process of voting on funding for Zika vaccine and treatment research, as well as mosquito control programs, but Halloran says any funding would likely target states according to their degree of risk. 

“We’re a low-risk zone, so it’s unclear at this point what kind of funding Washington state would receive, should federal funding become available,” she says.

Halloran says that testing for the virus is expensive and is limited to those who fit the criteria. 

“Testing is limited to those who have traveled to affected areas who exhibit at least two symptoms, symptomatic or asymptomatic pregnant women, and pregnant women who have had intercourse with someone who has tested positive for Zika,” she says.

Kim Papich, public information officer for the health district, says that while the risk of a Zika outbreak here is low, the organization is prepared to answer questions relating to the virus. 

“We understand people are concerned, particularly those who travel frequently,” she says. “That is why we encourage people to check with their health provider, and be aware of affected countries and changing seasons.”

Papich says Spokane County previously has looked into the possibility of implementing a mosquito control district to minimize cases of mosquito-borne viruses. However, the idea has gained little momentum over the years, as such a measure would mean higher taxes, and concerns over private property rights as well as environmental control. 

“Mosquito control is something most people feel they can manage through landscaping and maintenance on their own,” she says. “Fortunately, in the case of Zika virus, mosquito control isn’t needed locally, as our risk profile is basically zero.”