With the end of the rainy season in most of the Japanese archipelago, the heat has become intense as we enter full-blown summer. Warnings against heatstroke are necessary. It is necessary to be especially careful until our bodies get used to the heat.
Usually, many people suffer from heatstroke immediately after the end of the rainy season. It is because the body cannot adapt well to the heat. In July, the hours of sunlight were short and there were few hot days. With the spread of novel coronavirus infections, some people may not have been able to exercise enough to promote sweating.
The principle of heatstroke prevention is to drink water frequently and rest in the shade. Heatstroke is influenced not only by temperature but also by other factors, such as humidity and sunlight. Even if the temperature is not high, sweat does not evaporate on humid days and the heat tends to stay in the body.
It is also important to postpone or refrain from being active on days that are unsuitable for outdoor activities.
An international index called the wet bulb globe temperature (WBGT), which is calculated by taking into account such elements as temperature and humidity, is effective in assessing warning levels for heatstroke. When the index exceeds 21, attention is required. When it exceeds 31, it is desirable to stop exercising, in principle.
In July, the Environment Ministry and the Japan Meteorological Agency introduced a "heatstroke precautionary alert warning" system based on the index in Tokyo and the other eight prefectures in the Kanto-Koshin region. If the index is expected to be 33 or higher, a warning will be issued to call people's attention to it the day before or in the morning.
The JMA has issued more than a dozen warnings about high temperatures of 35 C or higher every year, but it has been difficult for people to actually feel the seriousness of the situation. The heatstroke alert has never been issued. It is expected that from now on the alert will be issued several times a year, making it a more accurate reminder.
From next summer, the alert system will be expanded nationwide. Hopefully, they will thoroughly examine this year's results and tasks remaining, and prepare for the full-fledged implementation of the system next year.
The situation this year is different from the past as measures are being taken to prevent infections with the coronavirus. Masks are indispensable even in summer to prevent the spread of airborne droplets. Even if rooms are air-conditioned, when they are crowded they must be ventilated to prevent infections.
It is important to strike a balance between measures against coronavirus infections and heatstroke prevention. The Health, Labor and Welfare Ministry advises people to take off their masks outside when they can get enough distance from others. This is because the risk of heatstroke increases if they continue to wear them doggedly.
Elderly people are more likely to suffer from heatstroke as well as severe coronavirus infections. This is because it is hard for them to sense heat and thirst. Elderly people with chronic diseases especially need to exercise caution.
Due to the blanket introduction of school closures, the summer holidays are shorter than usual and many children continue to go to school in the middle of summer. More attention needs to be paid to schools without air conditioners. It is hoped that schools will rack their brains so that club activities do not last long regardless of whether they are done indoors or outdoors.
-- The original Japanese article appeared in The Yomiuri Shimbun on Aug. 5, 2020.
Read more from The Japan News at https://japannews.yomiuri.co.jp/
