Zika, the mosquito-borne virus that can cause neurological birth defects and which the World Health Organization says is “spreading explosively” in the Americas, has entered the District, according to D.C.’s Department of Health. Two cases have been confirmed this year, and one was confirmed last year: All involved travel to South or Central America. One of the 2016 cases affected a pregnant woman.

Zika can also be transmitted through sexual contact, as the Centers for Disease Control and Prevention confirmed on Tuesday, citing a case in Texas. The virus typically manifests as a “mild illness, characterized by low grade fever, and a maculopapular rash, but can include symptoms such as myalgias/arthralgias, headache, conjunctivitis, pain behind the eyes, and vomiting,” per a DOH notice sent to medical providers Monday. “Severe disease is uncommon and no deaths have been reported.”

The agency also has a fact sheet on Zika, explaining that one in five people infected with the virus show symptoms.

Update 3:30 p.m.: DOH has provided City Desk with the following statement on the appearance of Zika in D.C.:

The [department] is working closely with the [CDC] to monitor and track Zika virus infections in D.C. residents. It is important for residents to remember that there is no immediate threat to their health and well-being if they have not travelled to the known affected areas. However, we must all stay well informed and be cautious when traveling internationally. DOH has created a webpage that will be regularly updated, with a fact sheet on the Zika Virus and other key information to ensure that all D.C. residents are engaged and informed.