Costa Rica and Nicaragua were added this week to the list of nearly 30 countries and territories U.S. authorities are warning pregnant women to avoid because of the presence of Zika virus.

The mosquito-borne virus, which is spreading rapidly throughout Latin America and the Caribbean, is suspected of being linked to birth defects in babies and to a rare neurological disorder.

Costa Rican health authorities have only detected two people infected with the mosquito-borne virus — both suspected of having contracted Zika elsewhere in Latin America.

But the Health Ministry reported this week that they had been informed by the U.S. Centers for Disease Control and Prevention (CDC) that a U.S. man had been diagnosed with the virus in January after visiting Costa Rica.

The man had been vacationing exclusively in the beach town of Nosara, in Guanacaste.

After receiving the news, the Health Ministry said it carried out a “massive fumigation” of the town on Sunday and Monday. The ministry also said it searched for other potentially infected patients in the area and didn’t find any.

Tourism industry worried about Zika panic

Leaders of Costa Rica’s travel industry expressed concern Tuesday about the country’s inclusion on the CDC’s Zika warning list. The Costa Rican Tourism Board (ICT) urged industry leaders and coastal towns to “take extreme preventive measures against the Zika virus, as we’re in high tourism season,” which runs from November through April.

The ICT also urged coordination among tourism businesses and communities to spread the word that Costa Rica “continues to be a safe place to vacation.”

The Zika virus has now been detected in every Central American country except Belize.

The World Health Organization said Monday that a spike in South America of a birth defect called microcephaly — a potentially devastating condition in which a baby is born with an abnormally small head and brain — was “strongly suspected” of being caused by the Zika virus and constituted an international health emergency. Nevertheless, the link has yet to be conclusively proven.

Zika is also believed to be linked to a neurological disorder called Guillain-Barre syndrome.

News of the virus has caused some travelers to Latin America to cancel or postpone trips to the region.

Massimiliano Devoto, president of the Costa Rican Association of Tourism Professionals, said the country’s inclusion on the U.S. travel alert “was a threat to tourism,” though he also hoped it would spur action to prevent the virus’ spread.

Costa Rica had nearly 2.7 million visitors in 2015, a country record. The tourism industry was responsible for more than $2.8 billion in revenue last year, and it employs roughly 600,000 people in Costa Rica through direct and indirect employment, according to the ICT.

New concerns that Zika could be spread sexually

Meanwhile, on Tuesday a county in Texas reported a case of Zika virus being sexually transmitted.

“The patient was infected with the virus after having sexual contact with an ill individual who returned from a country where Zika virus is present,” Dallas County Health and Human Services said in a statement. A spokesman for the county declined to identify the gender of the traveler or where he or she visited, though The New York Times said the person had visited Venezuela.

Last month the CDC said it was aware of one reported case of sexual transmission of Zika and one case of the virus being present in a man’s semen after it disappeared from his blood.

With information from AFP.