Why are this year's death figures in Japan below 2019's despite pandemic?

TOKYO -- Over a million people worldwide have died due to the coronavirus, and as of Oct. 10, 1,628 residents in Japan had passed away because of COVID-19, but official domestic death figures in the country for 2020 are lower than a normal year.

According to vital statistics from the Ministry of Health, Labor and Welfare, preliminary results up until July show that some 18,000 fewer people had died in Japan as of July 2020 than they had by the same time last year. So what has been going on in the background to the pandemic?

The health ministry's vital statistics are compiled from information on births, deaths, marriages, divorces and other data provided by municipal authorities. The preliminary figures are disclosed two months after the month surveyed, and approximate figures from a monthly vital statistics report on Japanese nationals living in the country are released some five months after the recorded month. The monthly reports are broken down by prefecture, cause of death and age, and the figures from May, when the state of emergency declaration was in effect, were released at the start of October.

The health ministry's population survey shows that in 2019, 1,381,093 people died in Japan. Since 2009, when the country saw a fall in deaths compared to the previous year, the number of dead has risen annually by between 17,000 and 33,000 people. But this year is different. According to the monthly report for May, the number of deceased in 2020 by that month was 13,851 lower than the year before. The preliminary figures up to July show that the number deceased was 795,807 people; down 17,998 compared to the 813,805 who had died in the first seven months in 2019.

But deaths by what type of diseases declined in 2020? May's breakdown by cause of death shows that up until that month, the greatest drop was seen in patients dying of respiratory illnesses, at 9,066 fewer deaths. Among them, influenza deaths had fallen by 2,270 people, and pneumonia by 5,863.

A health ministry official assigned to coronavirus policy posited, "Due to the coronavirus infection prevention measures, this year has also seen fewer cases of other infectious diseases across the board. It seems like cases of respiratory illness caused by infections have fallen because people have been reducing their time outside and avoiding close contact."

Looked at monthly, January saw the biggest fall in deaths, with a difference of 8,794 people. Reports of a new infectious disease in Wuhan, China, emerged at the start of the month, and by the middle of January the first patients in Japan had been confirmed, and with them coronavirus vigilance rose. Another month where the numbers fell noticeably was May, with a difference of 3,635 people. At that time, the state of emergency was extended to reduce transmissions, and there was a steep fall in rates of people leaving their homes or traveling. In May, the number of deaths from traffic accidents, falls and unexpected events was down 247 on the year before.

An official at the health ministry's Vital, Health and Social Statistics Office told the Mainichi Shimbun, "The reports of vital statistics are collated from surveys filled out by municipal authorities, so it's difficult for us to analyze the reason behind it."

But they added that generally, weather can have an effect on falling death totals. In 2009, when there were 542 fewer deaths than the year before, temperatures were high across the country, and around 8,000 fewer people died in February. According to the Japan Meteorological Agency (JMA), the winter from 2019 to 2020 was the warmest in both west and east Japan since its observations began in 1946, making it a "record warm winter." The official at the social statistics office said, "There isn't just one reason for the fall in deaths; it's a complex range of factors. Experts will probably analyze and evaluate the data in the future."

One other point of note is that the number of people dying from circulatory conditions has also fallen. By May, 6,724 fewer people were recorded as losing their lives to circulatory problem-related illnesses, and deaths from heart attacks and strokes were down by 1,608 and 1,318, respectively.

How have experts taken the information that so far deaths appear to be down by a wide margin compared to last year? Hiroshi Nishiura, a professor in theoretical epidemiology at Kyoto University Graduate School of Medicine who worked on the coronavirus outbreak predictor mathematical models, and who also researches demography, said that he thinks one of the reasons for the drop is that there was no widespread flu outbreak in the winter of 2019-2020.

The causes of death noted in the ministry's vital statistics are tallied based on the cause of death surveys, and are categorized based on rules set out by the World Health Organization. Annually, around 3,000 people in Japan die of influenza. But Nishiura said, "It's actually often the case that when a person becomes infected with influenza, not just existing respiratory conditions, but also circulatory, digestive and other chronic conditions worsen to the point that they die."

According to the health ministry, if both direct and indirect deaths by influenza are included, the death toll can, depending on the outbreak, be between 250,000 and 500,000 globally, and is reportedly estimated to be around 10,000 people in Japan alone.

Nishiura said, "It's come to be said that the number of people dying from causes brought on by influenza is quite high, and these documents have become a way of providing evidence for that argument. In the future, analysis of the figures by month may show us how variables in our living environment, such as stress from exercise and mental health factors, directly affect deaths."

(Japanese original by Sooryeon Kim, Lifestyle and Medical News Department)