A patient in Yolo County has tested positive for the Zika virus, according to health officials. However that patient did not contract the virus in the U.S.
"They came down with some of the signs and symptoms, a fever, a rash, after traveling to one of those countries and decided to seek medical help at that time, and that's when it was discovered," said Kristin Weivoda, Yolo County's emergency medical services administrator, at a press conference in front of the health department's building in Woodland.
Yolo County health officials would not state if the patient was male or female, what their age is or even which country they traveled to. But Weivoda was clear she does not expect the virus to spread within Northern California among those who have not been to the affected countries.
"This person got infected while traveling outside of the United States, so we do not have any concerns about that currently happening here," Weivoda said.
One reason they don't believe Zika will spread in the Golden State is mosquitoes common in the area are a different species from those in Brazil. The ones that are common here in California cannot carry the virus.
"These (mosquitoes that carry it) are more tropical mosquitoes, and so they're in more warm and humid areas," said Dr. Dean Blumberg, chief of pediatric infectious disease at UC Davis Medical Center in Sacramento.
Blumberg said while the Asian tiger mosquito has never been found in Yolo or Sacramento counties, they have been seen in California, especially in the LA area, and in small numbers in southern Bay Area counties. The yellow fever mosquito can also carry the virus, but has only been found in limited numbers in California.
"But it's been very sporadic and low concentrations," Dr. Blumberg said of the Asian Tiger mosquitoes' appearances in California.
Symptoms of Zika include a fever, rash and itchy red eyes, but they are not guaranteed, Dr. Blumberg said. He added most people who get the virus survive.
"Almost everybody that gets the disease gets better. So 80 percent of people who are infected don't even have any symptoms, they don't even know that they were infected at all," Blumberg said.
He said the most at-risk group are woman who are or may become pregnant.
"There's a risk it can adversely affect the fetus and the main concern is it can cause microcephaly, small head."
Meanwhile, Weivoda said the Zika patient has no travel restrictions.
Blumberg said there is another way he or she could spread the virus.
"Sexual transmission is another way this virus can cause infection," Blumberg said.