TOKYO -- The Yomiuri Giants professional baseball team announced on Thursday that two players who had tested positive for the new coronavirus showed negative results after additional checks and plans to continue regular monitoring of club members even after the season begins.
Testing at the end of last month determined that they had antibodies for the virus and subsequent polymerase chain reaction, or PCR, exams determined that they were positive.
The players -- shortstop Hayato Sakamoto and catcher Takumi Ohshiro -- have both shown no symptoms. The team will monitor the latest negative results and their physical conditions as well as consult with medical experts to decide when they can rejoin team activities.
The Giants announced positive results on Wednesday and canceled a practice game with the Saitama Seibu Lions scheduled on the same day. According to an explanation by team experts, Sakamoto and Ohshiro were infected with the virus some time ago and had already recovered. Still, the Giants gave fresh PCR tests to the two on Wednesday, the results of which showed no sign of the virus.
The Tokyo-based team had 218 people including its manager, coaches and players take antibody tests from May 29 to May 31 and found four positive results. Subsequent PCR tests confirmed that Sakamoto and Ohshiro were infected.
Members of the Giants will continue to take PCR tests on a regular basis after the season gets underway, according to the team.
The team's aggressive approach to testing comes as Japanese companies and businesses are looking for ways to effectively and safely resume operations after a national state of emergency to rein in the spread of the virus ended late last month.
How best to determine the extent of infections has been controversial in Japan, where the government has downplayed the need for widespread testing even as some doctors and infectious disease experts have vocally advocated it. Some experts point out that using positive antibody tests as a screening method for performing PCR tests could be an effective model.
The infections of Sakamoto and Ohshiro were the first to be reported by the Giants. The rival Hanshin Tigers announced on April 18 that three of its players tested positive.
Japan's professional baseball organization postponed the start of the 2020 season to June 19, some three months later than normal, due to the spread of the coronavirus in the country. On June 2, teams resumed practice games, minus fans, for the first time since March 25. Both Sakamoto and Ohshiro played in the Giants' game on Tuesday.