Take steps to prevent heatstroke as summer temperatures abruptly rise

The end of the rainy season has been announced in various parts of the country. This year as well, many regions were hit by heavy rain, but it will not be long before the full-fledged hot season begins.

In the days immediately after the end of the rainy season, the body can struggle to keep up with changes in temperature, so the number of heatstroke patients increases rapidly. Special caution is needed.

Many people have likely been unable to exercise sufficiently due to the prolonged novel coronavirus pandemic. It is necessary to be aware that the risk of heatstroke is higher than usual due to a diminished ability to sweat. It is important to make efforts to consume fluids frequently and rest in a cool place.

Even when it is not that hot in terms of temperature, people tend to get heatstroke on days when the humidity is high or the sunlight is strong. In recent years, an international index called the wet bulb globe temperature (WBGT), which is calculated based on such elements, has been attracting attention.

Ahead of the opening of the Tokyo Olympics and Paralympics, the Environment Ministry and the Japan Meteorological Agency started from this year the full operation of a heatstroke precautionary alert system based on the WBGT index. When the index is expected to exceed a certain level, an alert will be issued on the evening of the previous day or early in the morning of the same day.

The system was introduced in the Kanto-Koshin region last year on a trial basis, but it is difficult to say that its use has become sufficiently widespread. It is advisable to use the alert system as a reference when planning outdoor activities and outings. In principle, exercise should be canceled or postponed on the days when an alert is issued.

Wearing a mask tends to trap heat. It is a must for guarding against the coronavirus, but caution is also required regarding heatstroke.

There have been cases in which children who were wearing masks for a long time became ill. The Education, Culture, Sports, Science and Technology Ministry says masks are not necessary in physical education classes. However, in some cases, children wish to wear masks or their guardians want them to, according to the ministry. If schools deem the situation to be dangerous, they should instruct students to remove their masks.

Elderly people are also prone to heatstroke, as it is hard for them to sense thirst and their bodies’ ability to regulate their temperature is weak. They must be wary of the fact that they could get heatstroke without realizing it.

People have an image of heatstroke occurring outdoors on extremely hot days, but most of the people who died of heatstroke in Tokyo’s 23 wards last year were indoors. Many reportedly did not use air conditioners. The elderly should be careful even when sleeping.

On days when an alert is issued, it will be important for the people around senior citizens and others to reach out to them and encourage them to use air conditioners.

Mass vaccinations against the coronavirus are underway in various parts of the country. Attention must also be paid to measures against heatstroke, such as installing cold air blowers and providing drinking water in waiting areas.

— The original Japanese article appeared in The Yomiuri Shimbun on July 15, 2021.