Despite reports of three Illinois cases of Zika virus, which is believed to cause birth defects in children, state health officials say the spread of the virus here is very unlikely.
“The type of mosquito, Aedes aegypti, that carries Zika virus has rarely been found in Illinois,” said Melaney Arnold, communications manager for the Illinois Department of Public Health, in a email interview. “This type of mosquito also cannot survive freezing temperatures.”
The three cases reported in Illinois include two pregnant women who tested positive for the virus after traveling to Honduras and Haiti, and last Thursday, a man became the third case, testing positive for the virus after traveling to South America.
Previously, Zika was reported to only be transmittable through bites from mosquitos in South America, Africa, Southeast Asia, and the Pacific Islands. But a case in Texas on Tuesday revealed the likelihood of sexually transmitting the disease. The Texas patient was infected after having sexual contact with an individual who developed symptoms after returning from a trip to Venezuela, according to Dallas County Health and Human Services.
Illinois health department officials were unavailable for comment on the recent development.
Before the Texas case, there were only two documented cases linking Zika to sexual contact according to the National Center for Biotechnology Information. During the 2013 Zika outbreak in French Polynesia, the semen and urine samples of a 44-year-old Tahitian man tested positive for Zika even when there were no traces in his blood samples. Likewise, in 2008, a Colorado microbiologist contracted Zika after traveling to Senegal. A few days later, his wife was infected even though she had not left Colorado and had no exposure to any mosquitoes carrying Zika.
On average, one in five people infected with Zika virus become ill, according to the Centers for Disease Control. The symptoms of the virus are usually mild and last only about a week. These symptoms, which include fever, rash, joint pain, and conjunctivitis (pink eye) are similar to the flu, and can make Zika hard to detect. It is possible for those infected to not even be aware they have the virus.
“The greatest concern with Zika virus is among pregnant women,” Arnold said.
Medical research suggests a relationship between women infected with Zika while pregnant and a serious birth defect of the brain called microcephaly, said Aaron Diehr, an assistant professor at Southern Illinois University, who is also certified health education specialist. The birth defect, in mild cases, causes a baby’s head to be smaller than expected when compared to babies of the same sex and age. In more severe cases, the child’s brain could be underdeveloped and cause learning and motor disabilities.
“Babies are born with smaller heads, which creates neurological issues,” Diehr said. “There’s no causal link yet, but it seems to be highly correlated: pregnant who are getting this disease and babies who are born with this condition.”
There is no cure for microcephaly, and information about the link between Zika virus and microcephaly is evolving, Arnold said. Even though viruses cannot be cured, development of a vaccine could prevent contagion of Zika, but the creation of such a vaccine is many years down the road, Diehr said.
“It’s like the flu,” he said. “The flu is a virus, but you can’t really take medication to get rid of the flu. You just let it run its course, but you can take a vaccine [for prevention].”
The IDPH has a robust statewide mosquito surveillance system already and in place with more than 80 entities that can monitor for the Aedes aeqypti mosquito should they migrate this far north, Arnold said. But the possibility that Zika can be transmitted from person-to-person makes the approach of treating the disease different.
“Its something that we’ll have to keep monitoring,” Arnold said in a phone interview.
Earlier this month, Sen. Dick Durbin (IL-D) visited the CDC to discuss the issue of Zika with health professionals.
“The CDC is America’s first line of national defense when we are threatened with a public health crisis,” said Durbin, according to a state press release.
Since Illinois’s three cases of the Zika virus are contained at this time, state health officials recommend avoiding travel to tropical climates, especially for pregnant women.
“One of the greatest ways to avoid this right now is if you are a female and you’re expecting—probably a good idea to stay away from the South American tropical climates at this time,” Diehr said.