More airlines are offering refunds to passengers who have booked flights to countries in central and south America caught up in the Zika virus outbreak.
The relatively new mosquito-borne virus is connected with a neurological disorder that results in babies being born with abnormally small heads. There is no vaccine to prevent Zika or medicine to treat the infection.
Lufthansa (L) said any pregnant passenger, and their companion, can rebook a flight to any of the affected countries free of charge. This also applies to its affiliated carriers Austrian Airlines and Swiss.
British Airways, and its sister carrier Iberia, said pregnant customers with flights booked before Jan. 26 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.
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 (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."
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South American carriers LAN Airlines (LFL) and TAM Airlines are also offering to change tickets for pregnant passengers traveling to Brazil, Colombia, El Salvador, Guatemala, French Guiana, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto Rico, Surinam and Venezuela.
The Zika virus has spread to at least 25 countries. The Centers for Disease Control and Prevention is warning pregnant women against travel to those areas.
Health officials in several of those countries have told female citizens to avoid becoming pregnant, in some cases for up to two years.
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All the airlines said they are constantly reviewing their policies on refunds and changes to bookings. United has linked to the Center for Disease Control's Zika travel advice, which now includes Central America, South America and the Caribbean.