(Reuters) - The crowd at Copacabana's Beach Volleyball Arena loudly booed and taunted American volleyball players Lauren Fendrick and Brooke Sweat during an Olympic pool match Sunday, shouting "Zika" each time one of the duo served.
Their treatment follows U.S. women's soccer goalie Hope Solo also being roundly booed in a pool match against France on Saturday night because of her comments about the virus.
Neither Sweat nor Fendrick is known for expressing alarm over playing under the threat of the virus - indeed in an interview with a U.S. channel last week, Fendrick called the water quality in Brazil and Zika "non-factors" for the duo.
But with some high profile U.S. competitors having withdrawn from the Games citing their concerns over Zika, other U.S. athletes also appear to have become targets for vocal criticism.
In February, the U.S. Olympic Committee told U.S. sports federations that athletes and staff concerned for their health over Zika should consider not going to the Games.
American golfer Dustin Johson is among several top-ranked men in the sport who dropped out over Zika fears.
In June, American cyclist Tejay Van Garderen withdrew his name from consideration for the U.S. team, also citing concern over the virus.
Global health officials are racing to better understand the virus behind a major outbreak that began in Brazil last year and has spread to many countries in the Americas.
In the match, Fendrick and Sweat started strong against Poland's Monika Brzostek and Kinga Kolosinska, winning the first set 21-14, before falling apart and losing the following two sets 13-21 and 7-15.
Reporting by Amy Tennery; Editing by Alison Williams