A woman who had traveled to the Dominican Republic has become Chester County's first confirmed case of the Zika virus, county officials said Tuesday.

She is one of at least 23 confirmed cases of Zika in Pennsylvania, according to the Chester County Health Department. All cases involved travel to areas affected by the virus, which is believed to cause birth defects. The Chester County woman, who is not pregnant, was not hospitalized and has recovered.

The federal Centers for Disease Control and Prevention notified the Health Department of the case Monday. The department then told the woman, whom county officials declined to identify other than to say she is older than 50.

The department has alerted all county health-care providers, and reiterated the importance of following proper testing and risk-reduction guidelines.

Jeanne Casner, director of the department, said the risk of contracting Zika from mosquitoes in Chester County was minimal, and urged caution for anyone traveling to countries with mosquitoes carrying the virus.

Most people who are infected with Zika do not have symptoms. For others, symptoms can include rash, joint pain, fever, pink eye, muscle pain, and headaches.

mbond@phillynews.com

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