Key Points - "Slightly Positive" in 2020 and Six Games in 2022
On June 3, 2020, the Yomiuri Giants announced that Hayato Sakamoto and Takumi Oshiro had tested positive in PCR tests, and the announcement described their condition as "slightly positive." The expert who had used the word in conversation with the club explained on June 8, "It is not a medical term, so please understand," and asked the press not to use it either. The two were discharged on the night of June 12, the day the national discharge criteria were relaxed.
In July 2022, a total of 81 players, coaches, and staff tested positive in the 12 days from July 19. Yomiuri could not play after its July 20 game against Yakult, and six games, a three-game series against Chunichi and another against DeNA, were postponed. That was close to a third of the 19 games NPB postponed in 2022.
| Date | Event | Positive cases |
|---|---|---|
| July 19 | Farm-team players, coaches, staff | 17 |
| July 20 before game | Two players incl. Taisei | 2 |
| July 20 after game | Regulars incl. Sugano, Maru, Okamoto | 38 |
| July 21 | Shun Yamaguchi and others. Chunichi series postponed | 10 |
| July 22 | Manager Hara and others. 37 of 69 roster players | 6 (73 in 4 days) |
| July 23 | Coach Tetsuya Yamaguchi and others | 3 (76 in 5 days) |
| July 30 | July 31 DeNA game also called off. Tateoka and others at night | 4 (81 in total) |
Figures for July 19 to 21 come from the Number Web article (August 5, 2022); those from July 22 onward come from newspapers and club announcements.
2020 - From Antibody Tests to the "Slightly Positive" Announcement
From May 29 to 31, 2020, the Yomiuri Giants invited all players on the first to third squads, the manager, coaches, and team staff, about 220 people in all, to volunteer for antibody tests as part of a university medical school study. Four players and staff members were found to have IgG antibodies, which indicate recovery from infection.
The club gave the four PCR tests on the evening of June 2, and on the morning of June 3 Sakamoto and Oshiro were found positive. That day's announcement read: "The amount of novel coronavirus genetic material (CT value) in the two was minute, corresponding to a 'slightly positive' result just at the edge of the normal range, and since both have IgG antibodies showing recovery, we have received the view from experts that a considerable time has passed since both recovered from infection." It added that the two had had "no health problems at all since late March." Their positive results are also covered in the article on COVID-era discipline violations.
According to the June 12 announcement, the two players' Ct values were 37.78 and 34.95, which the club described as "values just at the edge of the level at which 40 or above is considered negative." These two Ct values were what the club cited as the basis for "slightly positive."
The Expert's Explanation and Ten Days to Discharge
On June 8, Mitsuo Kaku, a specially appointed professor at Tohoku Medical and Pharmaceutical University and head of the expert team of the Novel Coronavirus Countermeasures Liaison Council of professional baseball and the J.League, revealed that "slightly positive" was a word he himself had used in conversation with the club, and explained, "It is not a medical term, so please understand." According to the Sankei Shimbun, he asked reporters, "It came up in conversation, so I would like you not to use it (in reports)."
The two players' PCR tests on the evening of June 3 and the morning of June 5 were both negative. On June 5 the public health center recommended that their hospital stay be extended until June 15, based on a Ministry of Health, Labour and Welfare notice under which an asymptomatic positive case did not meet the discharge criteria until 14 days had passed since the positive specimen was collected. A third PCR test on June 6 was also negative, as was a virus isolation test by a research institution.
The June 12 announcement wrote that several members of the government's expert panel had questioned whether "it can be called reasonable for the hospital stay to be longer than for positive cases who developed symptoms." On June 12, the ministry decided to relax the discharge criteria for asymptomatic positive cases, changing "14 days" to "10 days" among other changes, and the two were discharged that night. They had been in the hospital for 10 days, and the club wrote, "We regard this relaxation of the discharge criteria as a step forward."
July 2022 - How the Cluster Unfolded
A Number Web article (August 5, 2022) wrote that on July 19, 17 people including Yuki Takahashi of the farm team tested positive, and that on July 20 two players including Taisei were found infected before the game against Yakult at Jingu Stadium, followed after the game by 38 positives including regulars Tomoyuki Sugano, Yoshihiro Maru, and Kazuma Okamoto. The same article says that on July 21 another 10, including Shun Yamaguchi, tested positive, leaving 34 players, about half of the roster players eligible for first-team games, unable to play.
On July 22, six people including manager Tatsunori Hara tested positive, bringing the total to 73 in the four days from July 19. Hara was expected to withdraw as a coach for the All-Star Game, and the five players who had tested positive on July 20 also withdrew. Only 10 position players were available that day: two catchers (Kobayashi and Hagiwara), three infielders (Yoshikawa, Hirooka, and Kikuta), and five outfielders (Polanco, Walker, Shigenobu, Ishikawa, and Okada).
On July 23, three more, including first-team pitching coach Tetsuya Yamaguchi and Hirokazu Kikuta, tested positive, bringing the five-day total to 76. Under NPB's guidelines, asymptomatic cases could be released from isolation on the eighth day after specimen collection. On the night of July 30, four more, including Soichiro Tateoka, tested positive, and the total since July 19 reached 81.
The Six Postponements and How the Club and NPB Explained Them
On July 21, an extraordinary meeting of the 12 clubs' executive committee decided to postpone the Chunichi series starting July 22, and Yomiuri halted team activities. According to NPB's "Three-Year Review of Novel Coronavirus Countermeasures," extraordinary executive committee meetings held on July 21, 26, and 28 decided to postpone the six games of July 22 to 24 and July 29 to 31 (the July 29 game was decided through consultation between the host club and NPB). The pandemic's impact on NPB as a whole is covered in the article on NPB during the COVID era.
The club issued a detailed announcement on July 30 about the cancellation of the DeNA games. Thirty-eight of its 69 roster players had tested positive, and excluding the injured, only nine position players could play, two of them infielders. On July 28 the club moved developmental-contract infielder Shoki Katsumata into the last of its 70 roster spots, raising its available infielders to three, but saying it was still one short, it asked to cancel the July 29 and 30 games against DeNA. Of the infielders who had finished isolation, the three who returned earliest, on July 27, were judged on the evening of July 29 to need several more days before their upper- and lower-body strength returned to the level of official games, and because playing them could lead to a serious injury, the club judged it "impossible" to put any of the three on the bench for July 31. With "only three of the four infielders originally needed expected to be available for the July 31 game," the announcement wrote, "We obtained approval for the cancellation at an extraordinary executive committee meeting of the 12 clubs held by circulation."
NPB's 2022 guidelines provided that if "26 players for the bench (or the number of players the club in question considers sufficient to play the game)" were not available two hours before a game, the game could be canceled in advance "with the approval of the league and the opposing club," and Attachment 4 stated that "cancellation will be considered, using the inability to form a team two hours before the start of the game as a guide." According to NPB's review, two games for SoftBank, where 18 people tested positive, two games for Yakult, and in April four DeNA games and two Rakuten games were also postponed in 2022. Number Web wrote that Yakult postponed only two games even when 18 people including manager Shingo Takatsu tested positive, and played the three-game series from July 12 by calling up farm players, going 2-7 in the nine games until Tetsuto Yamada returned on July 24.
Our View - The Wording of the Announcement and the Latitude of the Rules
The problem in 2020 was the wording of the club's official announcement. The club used a non-medical word that an expert had spoken in conversation to describe the two players' condition, and five days later the expert himself had to explain that it was "not a medical term." The Ct values and test results would have been enough; there was no need to add an undefined word.
The national government relaxed the discharge criteria for asymptomatic positive cases on June 12, and the two players were discharged that same night. In that day's announcement, the club wrote that it regarded the relaxation of the national criteria as "a step forward," placing it alongside the discharge of its own players.
The six games in 2022 were close to a third (6 of 19) of all postponements that year, more than the two games postponed for each of the SoftBank cluster (18 positives in NPB's review) and the Yakult cluster (18 in the Number Web article). The process followed the guidelines, and the postponements cannot be called improper. But the phrase "the number of players the club in question considers sufficient to play the game" leaves much of the decision to the club itself, making it hard for outsiders to see how many absences justify stopping play.
The explanations were not consistent either. Number Web wrote that when the Chunichi series was postponed, NPB secretary general Atsushi Ihara gave only the broad reason that a team "could not be formed" at his press conference, without showing the shortage of infielders, and contrasted this with the club explaining its reasons twice on its website for the DeNA postponements, down to the number of infielders and how far their strength had recovered. The same article also reported fans asking why Yomiuri alone had six games postponed. The decision not to rush players back from isolation protects them and is not the target of criticism. The issue is that postponements caused by the same cluster were explained in different ways.
How to Read This Article and Its Limits
This article is based on three Yomiuri Giants announcements, NPB's guidelines and review, and the text of newspaper articles. The Number Web article, which includes commentary, was used only in the form of what the article wrote.
What can be confirmed about "slightly positive" is that an expert used it in conversation and the club used it in its announcement; it cannot be said that the club deliberately coined the word. That the relaxation of the discharge criteria and the discharge fell on the same day does not imply any lobbying by the club either. Comparisons with other clubs are limited to what NPB's review and the Number Web article showed, and the players' symptoms and the results of games after the postponements are not covered.