SACRAMENTO (CBS SF) – The state’s Department of Public Health is advising residents Monday to take precautions against mosquito bites in light of the recent Zika virus infections that have occurred in other countries.

So far, there have been six confirmed cases of the virus in California, all of which were contracted while the patient was traveling outside of the country, health officials said.

The first case in California happened in 2013 then three cases were reported in 2014 followed by two cases in 2015.

Because of patient confidentiality, the location of the infected California patients has not been disclosed, according to health officials.

“Although no one has contracted the Zika virus in California, mosquito bites can still be harmful and the public should take steps to protect themselves,” the CDPH’s Director and State Public Health Officer Dr.  Karen Smith said in a statement.

In order to prevent mosquito bites, residents can remove standing water near their home and should apply insect repellant when necessary, health officials said.

The Center for Disease Control and Prevention has issued travel alerts for people traveling to countries and regions where the Zika virus is circulating. Those places include American Samoa, Brazil, Colombia, Costa Rica, Curacao, El Salvador, French Guiana, Guatemala, Haiti, Honduras, Martinique, Mexico, Nicaragua, Panama, Paraguay, Suriname, Venezuela and Puerto Rico.

The CDC and CDPH is also warning pregnant women to avoid traveling to those countries because of a concern that a pregnant woman can transfer the virus to her baby during pregnancy or delivery.

Preliminary reports suggest that the Zika virus may cause microcephaly, a condition where the fetal brain develops abnormally. This possibility, however, has not been confirmed and health officials are actively investigating the link, according to the CDPH.

Most people infected by the virus do not develop symptoms. If symptoms do develop, they are usually mild and include fever, rash and red eyes.

While there is no specific treatment yet for the virus, anyone with who has returned from an affected country and has symptoms should contact a doctor, health officials said.

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