Growing fears about the spread of the Zika virus led to more than 1,000 people canceling their international flights in February, according to Korean airlines on Thursday.

They said a total of 1,376 pregnant women and family members had canceled flights to countries where Zika virus infections had broken out. These flights had been booked with either Korean Air, Asiana Airlines, Jeju Air, Jin Air, Eastar or T’way Airlines. 

These six Korean airlines, which include low-cost carriers, have been offering fee waivers for flight refunds or reservation changes for pregnant women and their families who had booked tickets to countries with infection cases. One other Korean carrier, Air Busan, had no cancellations because it offered no direct flights to infected countries.

The Zika virus in pregnant women has been linked to serious birth defects including microcephaly, which causes babies to be born with unusually small heads. 

Most Korean carriers do not offer direct flights to many of the infected countries, which are mostly in Central and South America. The vast majority of the canceled flights have been to Thailand -- roughly 820 passengers to Bangkok and 410 to Phuket. Thailand is a popular vacation spot for Koreans and one of two Asian countries identified on the nation’s disease control agency’s list.

The other is the Philippines, which was added to the list on Tuesday. More flights are expected to be canceled, as the Philippines is another popular destination. Air Busan offers one flight a day to the Philippines, and will now be offering fee exemptions for passengers who wish to cancel those ticket bookings. 

Currently, the six carriers offer fee waivers for flights booked before Feb. 1, and scheduled to fly before April 30.

There are currently 39 countries identified by the disease control agency as danger zones, up from 26 in January. There has yet to be a patient diagnosed with Zika infection in Korea.

By Won Ho-jung(hjwon@heraldcorp.com)