Top US airlines United and Delta have offered to re-assign certain flight crew concerned about contracting the Zika virus from routes to Latin America and the Caribbean, the companies told Reuters on Wednesday.
The previously unreported policies show how the mosquito-borne virus, linked to thousands of birth defects in Brazil, looms as an issue not just for airline passengers but for flight attendants and pilots as well.
In an internal memo on January 28, seen by Reuters, United said expectant flight attendants as well as those seeking to become pregnant could switch routes to avoid Zika-affected regions without repercussions.
The airline has similar options available for pilots, said Charles Hobart, spokesman for parent United Continental Holdings Inc.
Delta Air Lines Inc. has also let flight attendants and pilots switch assignments since January 17, and "a small number of crew members have swapped trips to date," spokesman Morgan Durrant told Reuters.
"We have immediate concern about our members' health," said Sara Nelson, international president of the Association of Flight Attendants-CWA, when asked for comment on United's memo.
"This issue is changing at a fairly rapid pace, (and) it's important that those updates are ongoing," she said, adding that airlines appeared to be responding faster to employee concerns than they did during past outbreaks, such as the spread of Ebola in 2014.
Airlines and hotel chains have said it is too early to tell if the Zika epidemic is affecting bookings.
However, top US carriers, including United and Delta, are offering refunds for flights to impacted areas. Travel agents also say "babymooners" – parents-to-be taking last-hurrah vacations – have backed out of trips and changed itineraries.
Concern about Zika has been magnified in recent days by a reported case of sexual transmission in Texas as well as a global health emergency declared by the World Health Organisation.
The US Centres for Disease Control and Prevention has urged pregnant women to consider delaying travel to locations hit by Zika, for which there is no treatment or vaccine.
"The safety of our employees and customers is paramount, and we are providing this option because it's the right thing to do," Hobart said.
United, the second-largest US airline by capacity, declined to address whether it was concerned about crew shortages resulting from the January 28 notice. The carrier has some 20,000 flight attendants worldwide.
The memo said flight attendants can drop their re-assigned trips, without pay, if United is able to find replacements for them.
United declined to say how many flight attendants have asked to switch their assignments.
Swiss International Air Lines said that it would not require female crew to fly to Sao Paulo, according to a Tuesday report from the Associated Press. A spokesman for parent Deutsche Lufthansa AG could not immediately confirm the report.