Officials confirmed Tuesday that a young girl from Los Angeles County was infected with the Zika Virus.

The outbreak of this mosquito-borne illness was reported in Brazil last May. Since then, the virus has spread across 20 countries in Central and South America, arriving now in the United States.

The Los Angeles Department of Health believes the girl contracted the illness while traveling in El Salvador last November. While she has since recovered from the virus, more reports of Zika Virus cases are appearing throughout the U.S. in New York, Virginia, and Arkansas.

"Right now the cases are mostly imported and the chance is good that it will spread more in the U.S.," said Keck School of Medicine Professor James Ou, an expert on emerging pathogens.

It should be noted that Zika is not contagious and most of the cases in the U.S. were contracted while abroad. The virus can only be transmitted if a mosquito bites a person who has the virus in their blood, and then bites another person.

More recent reports show that Zika may also be transmitted through blood transfusion or sexual intercourse, according to the Center of Disease Control and Prevention.

The most common symptoms include: fever, rash, joint pain, and red eyes, but even then, most people infected with Zika don't experience the very mild symptoms.

So, why the hysteria?

Last year, thousands of babies in Brazil were been born with abnormally small heads and impaired brain function, a congenital condition called microcephaly. Public health experts suspect the spike in this serious birth defect is related to the Zika Virus outbreak.

Panic around the illness has increased with the CDC issuing alerts across the Americas and officials in Columbia, El Salvador, and Ecuardo advising women to not get pregnant. And now, the virus has infiltrated the U.S.

Professor James Ou says that while we should not be scared of Zika, we be aware of the dangers of the virus, especially pregnant women planning to travel to endemic areas.

Reach Staff Reporter Paulina Cachero here or follow her on Twitter here.