inspector Yang Yiran Zheng Shujing Wang Xinran
incident background
Recently, it was reported that after the Tokyo Olympics ended in mid-August this year, the new crown epidemic across Japan was effectively controlled, and the number of new confirmed cases showed a cliff-like decline.
According to data from the Ministry of Health, Labor and Welfare of Japan, starting from October 7, the number of new confirmed cases in Japan fell below 1,000. On October 31, a total of 215 confirmed cases across Japan, and 14 new cases were cleared out in 47 prefectures. In Tokyo, there were only 9 new confirmed cases on November 1.
Ministry of Health, Labor and Welfare Visual data
However, while the number of confirmed cases announced in Japan continues to decline, doubts such as "data fraud" are gradually aroused. Recently, Kim Yujun, a famous Korean current affairs commentator, accused the Japanese government of "fraud" in his personal program "Kim Yujun's News Factory", saying that Japanese media did not point out the government's misconduct. At the same time, doubts about this data are also common on Chinese social media. Some voices said that the "cooling of the epidemic" on Japan's surface may be caused by the decrease in the number of in nucleic acid tests.
So, are the confirmed data released by the Japanese government accurate? Has the number of nucleic acid tests decreased? Are there other explanations that may lead to a decrease in infection rate?
Is the diagnosis data accurate?
The Ministry of Health, Labor and Welfare has attached an explanation of the data source and statistical methods below the chart of the number of new confirmed cases published in a single day. The description shows that the number of new confirmed cases in Japan is calculated based on the data of the HER-SYS system. However, the values from the date of information update to 14 days are calculated by cumulative number of cases (including re-positive cases) released by local governments.
According to the Ministry of Health, Labor and Welfare, HER-SYS is a national information collection system designed by the Japanese government to respond to the new crown epidemic and will be put into use at the end of May 2020. Any medical institution or individual can report diagnosis information in a timely manner by logging into the system.
Nevertheless, the accuracy of the data obtained by HER-SYS statistics is often questioned. As early as mid-February this year, the Japanese News Agency reported that the Minister of Health, Labor and Welfare, Masara Masara, publicly admitted to the public at the House of Representatives meeting held on February 17 that the Japanese government's practice of counting the number of new coronavirus infections was entrusted by outsourcing company employees to go to the official website of 47 prefectures and prefectures to confirm the data with human eyes on the official website of 47 prefectures and prefectures, and then manually calculate it. The then Japanese Prime Minister Suga Yoshihide also expressed his knowledge of the matter.
On October 30, the Japan Broadcasting Association (NHK) reported that the Tokyo Metropolitan Government announced on October 29 that it would make a large-scale correction to the number of infections announced within the six months from April 2, 2021 to October 2, 2021. A total of 4,512 new coronary pneumonia infections have been missed, and another 447 cases have been repeated, which means that the actual number of virus infections in Tokyo needs to increase by 4,065 in the past six months.
When reporting on the amendment, the Daily News pointed out that the information of the infected person is stored in the HER-SYS database. It is logical that when using this system, the staff of the Public Health Organization need to click a special button to indicate that these cases have been confirmed by the Public Health Center. However, in practice, a large number of public health organizations have forgotten to confirm the data because they are busy responding to patient needs. A Tokyo Metropolitan Government official admitted to the Daily News: "We are reflecting on this fact, and we cannot accurately convey the daily (confirmed) numbers." Is the nucleic acid test volume reduced?
According to the Ministry of Health, Labor and Welfare of Japan, people who are judged by doctors as potentially infected people need to undergo nucleic acid testing. In addition, in Japan, people can apply for testing on their own, and the testing is provided by governments, universities, local organizations, private institutions and other parties.
Oxford University "Our World in Data" project shows that since early September, the average daily number of tests in Japan has begun to decline, and the number of new confirmed cases has also begun to decline every day. Since September 25, the number of tests per 1,000 people in Japan has been less than one thousand. The decline in the number of detections in
may be related to the decline in the number of active consultations among Japanese people.
Take Tokyo as an example. Official data shows that since September, the number of consultations in fever consulting centers and the number of acceptances for COVID-19 consulting hotlines have dropped significantly. From September 1 (926) to October 31 (77) the number of COVID-19 consultation hotlines dropped by 91.7%.
Accordingly, in the first week of September (August 30 to September 6), a total of 101,177 samples were tested in Tokyo, while in the last week of October (October 25-October 31), the number of samples tested decreased to 40,251, and the total number of tests decreased by 60.2%.
Although the number of new confirmed cases may not be strictly positively correlated with the number of nucleic acid tests, from the trend point of view, the decline in the number of new confirmed cases in Japan every day does seem to be related to the decrease in the number of nucleic acid tests.
In addition, although the number of tests is declining, the detection rate of positive in Japan has increased significantly compared with August, rising from below 6% to around 7%.
Japan's positive COVID-19 detection rate (May 7, 2021-October 30, 2021)
may lead to the decline in infection rate
" New York Times " reported on October 28 that even Japanese experts do not know what exactly caused the sudden decline in the number of new infections in Japan every day, but they all believe that high vaccination rates and the behavior of wearing masks for the whole people may be important factors in curbing the spread of the virus.
How high is the vaccination rate in Japan? The latest statistics from the "Our World in Data" project show that as of November 1, about 78% of the people in Japan completed the first vaccination, and 73% of the people completed the full vaccination, with an average of 150 vaccinations per 100 people.
Compared with Japan, 80% of the people in South Korea have completed the first dose, 75% of the people have completed the complete dose, and the vaccination volume per 100 people has reached 152 doses. However, since early July, in South Korea, where the total population is less than half of Japan, the daily increase in cases has always remained above 1,000, and it has shown a continued upward trend.
South Korea has added new confirmed cases of new coronavirus every day (May 1, 2020-November 2, 2021)
According to statistics, since April this year, the number of vaccinations per 100 people in Japan has been increasing, but the number of new confirmed cases per day has not decreased simultaneously with it. Since July, the number of new confirmed cases in Japan has been rising, with the highest daily increase of more than 23,000. This trend was not gradually curbed until the gradual end of the Olympic season in late August, but the number of confirmed cases was still at a high level. It was not until early October that Japan's daily new cases fell below 1,000.
Number of COVID-19 vaccination doses per 100 people in Japan (April 14, 2021-November 1, 2021)
Number of new confirmed cases of COVID-19 every day (May 17, 2021-November 2, 2021)
Therefore, the sudden "cooling" of the epidemic in Japan is attributed to vaccination or inaccuracy.
In response to the cliff-like decline in the number of confirmed cases, Japanese officials also gave many other explanations, including the reduction of personnel flow, active cooperation among the people, and the easing of congestion in medical facilities. Reuters interviewed Hiroshi Nishiura, a professor at Kyoto University in early October, who said the main reason for the surge in summer and the subsequent sharp drop was the change in human activities.
Mid July to early September is the traditional summer vacation for Japanese schools, which is interspersed with national holidays such as the day of the sea (July 22), the day of sports (July 23), and the day of the mountain (August 8). Nishiura Hiro believes that during holidays, people are more likely to interact and eat in a face-to-face environment, which in turn aggravates the spread of the epidemic. He also pointed out that the new round of epidemic growth in South Korea and Singapore since September may also be related to their mid-year holidays.
Japanese government's new crown epidemic expert group leader Oshishima also expressed a similar opinion at a press conference on September 28, saying that as the holidays end, the flow of people decreases and the efficiency of virus transmission decreases.
However, it is still difficult to determine what factors play a decisive role in Japan's epidemic prevention and control. However, a saying has been circulated in Japanese academic circles recently that the toxicity of the new coronavirus may have weakened.
According to the Japan Kyodo News Agency, on October 30, the National Institute of Genetics and Niigata University published a joint study, believing that the slump of the epidemic in Japan may be related to changes in an enzyme called "nsp14" in the new coronavirus delta strain . This enzyme can repair the virus and make the virus proliferate continuously. With the decrease in the effect of nsp14 enzyme, the new coronavirus has no time to "repair mutation", resulting in its own digestion.
National Institute of Genetics and Niigata University study the operating mechanism of weakening of toxicity in poisonous strains
This research result was originally published by Professor Ionoguchi Yiran from the National Institute of Genetics on October 15 at the 66th Congress of the Japanese Society of Human Genetics. However, it can be seen from the topics published by the conference that the main target of Inoka research is the new coronavirus mutation strain in Shizuoka Prefecture . Whether its research results can be extended to other prefectures in Japan is still to be discussed.
Based on the current information, you can know that
Japan's new confirmed cases is not necessarily completely accurate ;
Compared with the past few months, the daily nucleic acid tests of in Japan have decreased significantly , but the positive detection rate has increased significantly compared with August;
Although it is difficult to confirm what factors have caused the cliff-like decline in the number of new confirmed cases in Japan recently, the decrease in personnel flow, Japanese people's active consultation and detection number , and toxicity of the new coronavirus itself have weakened , , and toxicity of the new coronavirus has all provided possible explanations for this phenomenon.
This issue is edited by Zou Shan
