Airlines are offering refunds to passengers who have booked flights to central and south American countries caught up in the Zika virus outbreak

The mosquito-borne Zika virus is spreading so quickly through the Western Hemisphere that it is soon expected to reach virtually every country in the Americas. The virus has already affected more than a million people in Brazil, and it’s likely to reach the continental United States this year.

The relatively new mosquito-borne virus is connected with a neurological disorder that results in babies being born with abnormally small heads. At the moment, there are no vaccines to prevent, and no medicines to treat the Zika virus.

Thus far, 24 countries worldwide — including Mexico and Brazil — have reported active transmissions of the Zika virus.

The World Health Organization (WHO) issued its own alert on Monday, saying it expects the Zika to eventually spread to the United States and most of the Americas.

Currently, the CDC’s advisories mention the following countries and territories in the Americas: Barbados, Bolivia, Brazil, Colombia, Ecuador, El Salvador, French Guiana, Guadeloupe, Guatemala, Guyana, Haiti, Honduras, Martinique, Mexico, Paraguay, Panama, Puerto Rico, Saint Martin, Suriname and Venezuela.

Now airlines are reacting to the outbreak by offering passengers with tickets to infected regions the opportunity to change their plans, free of charge

USA’s biggest airlines are allowing some customers to cancel or postpone their trips if they’re ticketed to fly to areas affected by Zika.  American, United and Delta each made the move this week amid rising concerns about the mosquito-borne virus.

Workers in hazmat suits in Rio de Janiero.

Workers in hazmat suits in Rio de Janiero.

United and Delta will allow customers concerned about the Zika virus to cancel or postpone their trips if they’re ticketed to fly to areas affected by Zika. American Airlines also said it would allow certain customers to do the same.

American Airlines:

American Airlines (AAL) is offering pregnant passengers a full refund if they provide a doctor’s note showing they are unable to fly to the following cities: San Salvador (El Salvador), San Pedro Sula and Tegucigalpa in Honduras, Panama City and Guatemala City.

United Airlines:

United Airlines (UAL) said its giving any customers “who are traveling to the affected regions the opportunity to rebook at a later date or receive a full refund.”

United’s policy includes travel to all areas mentioned in a Centers for Disease Control alert. So far, American’s covers flights to four destinations in Central America.

“We are offering customers who are traveling to the affected regions the opportunity to rebook at a later date or receive a full refund,” United spokesman Charles Hobart said in a statement to Today in the Sky on Tuesday.

Delta Air Lines:

In response to the Zika outbreak, Delta issued the following travel advisory:

“Customers with current reservations who are concerned about traveling to destinations reported by the CDC to be affected by Zika Viral Illness should call 1-800-221-1212 (U.S.) or your local Reservations office and speak with a Delta Representative. Customers may qualify for a change to alternate destinations, travel dates or a refund. Customers may make fee-waived changes to future reservations/tickets. However, changes need to be made by February 29, 2016.”

British Airways

British Airways said pregnant customers with flights to Sao Paulo and Rio de Janeiro in Brazil, or to Mexico City or Cancun (Mexico), could change their booking free of charge, delay their journey or choose an alternative destination. This applies through February.

Air France:

In response to the outbreak, Air France has issued to following statement to Business Insider:

Air France confirms that the Zika virus has had no impact on its flight operations and service to the destinations concerned. The Company continues to closely monitor the situation, and is in direct contact with the French and international health authorities (French Health Ministry, WHO, CDC, ECDC, IATA, etc.). Announcements are made on board flights to the regions affected by the virus to inform customers about the precautionary measures to observe. Flight crews have also been informed about these same measures.