Zaferes attended North Carroll High School and Syracuse University, where she ran track at both. Turning professional in 2013, she raced her first top-flight ITU World Triathlon Series event on 19th April in San Diego finishing 30th, and then went on to gain her first ITU World Cup podium with Gold in Palamos on the 14th of July. In her debut year, Zaferes was awarded the USA Triathlon Elite Rookie of the year. The 2014 season yielded a number of podium results at ITU World Cup level including her sole career disqualification due to an irregular transition at T2 in Aukland. She earned her first podium in the ITU World Triathlon Series with a silver medal in Abu Dhabi on the 7th of March 2015, and following 6 podium finishes at ITU World Triathlon Series over the course of 2015 won her first WTS race in Hamburg on the 16th of July. Following this she had 10 podium finishes between her first WTS victory and her next, which came on the 8th March 2019 in Abu Dhabi. The 2019 season would go on to be her crowning achievement as she took wins in Bermuda, Yokohama and Montreal with a second place finish in Leeds, a 35th place finish in Hamburg following a crash, and a DNF at the Tokyo Olympic Qualification event which resulted in facial injuries. Despite this accident, some 15 days before the Grand Final in Lausanne, she took gold in the final to seal the overall title. In recognition of her achievements, USA Triathlon awarded Zaferes the "Women’s Olympic/ITU Triathlete of the Year". Outside the ITU, Zaferes also competes in Super League Triathlon. Zaferes year-over-year results in the ITU World Triathlon Series include finishing 42nd in her debut year of 2013, 16th in 2014, 5th in 2015, 4th in 2016, 3rd in 2017, 2nd in 2018 and taking the overall title in 2019.
2013—2016 seasons
Zaferes contested her first races as an elite athlete in the 2013 season, taking gold in the Palamos and Tiszaujvaros World Cup races. The following year Zaferes took gold in the New Plymouth World Cup race. Notably she contested the Aukland World Triathlon Series race, completing the swim, T1 and Bike portions of the race but receiving a disqualification in T2 due to "irregular transition". In 2015, Zaferes' had a break-out year, taking silver in five ITU World Triathlon Series races plus bronze in Gold Coast. She finished the season in 5th place overall. Next season, in 2016, Zaferes took her first ITU World Triathlon Series win in Hamburg. She also finished on the podium in Edmonton, taking bronze behind Summer Rappaport and Sarah True. She completed the 2016 ITU World Triathlon Series ranked fourth overall. As the top-ranked woman in USA Triathlon'sranking system, Zaferes was named to the triathlon team for the 2016 Summer Olympics where she finished 18th.
2017 season
For the second time in her career, Zaferes won the New Plymouth World Cup event. She was 1 second over second place Canadian Joanna Brown and 2 seconds over Belgian Claire Michel. This was the fourth time in a row an American won the race. She finished the season 3rd in the ITU World Triathlon Series rankings, beating out Kirsten Kasper in 4th place.
2018 season
Of the eight World Triathlon Series races in 2018, Zaferes finished on the podium in six of them, taking two silvers, and four bronze. At the season opener at Abu Dhabi, the race was contested with the bike and run legs on the Yas Marina race track. Zaferes crashed hard within the tunnel section and was unable to continue, registering a DNF. The remaining race of the season, Edmonton, resulted in a 6th place for Zaferes, notable as an uncharactaristically low finishing position in an otherwise high-placing and consistent season. At the grand final in Gold Coast, Zaferes came into the race needing to finish ahead of her rival Vicky Holland to take the series and the title of World Triathlon Champion. On the run leg, Zaferes, Holland and the Australian athlete Ashleigh Gentle were together by the second lap of four at the head of the race. Gentle managed to distance her rivals, ultimately finishing clear in first place. Zaferes opened a gap to Holland which remained for some time before Holland managed to close the distance to Zaferes and they entered the finishing chute together, with Holland beating Zaferes in a sprint finish to take silver in the race and the overall title of ITU World Champion. Zaferes finished the 2018 season in 2nd place overall in the World Triathlon Series rankings.
2019 season
Of the eight World Triathlon Series races in 2019, Zaferes finished in first place in five of them, taking the wins in Abu Dhabi, Bermuda, Yokohama, Montreal and the Grand Final in Lausanne. Of the other races, Zaferes took a second place finish in Leeds having been outrun by Georgia Taylor-Brown, a 35th place finish in Hamburg following a crash, and a DNF at the Tokyo Olympic Qualification event which resulted in facial injuries. Despite this accident, some 15 days before the Grand Final in Lausanne, she took gold in the final to seal the overall title. In recognition of her achievements, USA Triathlon awarded Zaferes the "Women’s Olympic/ITU Triathlete of the Year."
Personal life
Zaferes is married to fellow triathlete Tommy Zaferes.
