"He inflicted damage to both Croatia and to us as a family in Serbia," Srdjan Djokovic said. "Nobody is feeling well because of this situation."
Dimitrov, a three-time Grand Slam semifinalist from Bulgaria, was the first Adria Tour participant to test positive for the virus. He was followed by Borna Coric and Viktor Troicki.
The infections raised questions about the full-fledged return of competitive tennis, including the scheduled U.S. Open in August.
"We were wrong and it was too soon," wrote Djokovic, who has previously said he was against taking a vaccine for the virus even if it became mandatory to travel.
Dimitrov played in matches in both Belgrade and at the Croatian Adriatic resort of Zadar. He reportedly arrived in Serbia from the United States and his native Bulgaria. He did not immediately respond to The Associated Press' request for comment while recovering from the infection in Monaco.
NBA player Nikola Jokic, a Serb who plays for the Denver Nuggets, has also tested positive for the coronavirus. He was pictured shaking hands with Djokovic at an exhibition basketball event in Belgrade this month.
Jokic is reportedly recovering in his hometown of Sombor.
Djokovic's mother said both her son and his wife Jelena are feeling fine, but are suffering because of the widespread criticism.
"It is horrible what is being written, but we are used to it," Dijana Djokovic told the Belgrade Blic daily newspaper.
The coronavirus outbreak led to the suspension of the ATP and WTA professional tennis tours in March. Plans were announced last week for the sport's sanctioned events to return in August.
The U.S. Open is scheduled to begin Aug. 31 without spectators.