To avoid becoming sick and stay healthy in a foreign country, it is important to learn about local-common health problems as well as preventions. In Japan, summer heat and high humidity can lead to possible food poisoning, fatigue and heat stroke. In spring and fall, many people suffer from rhinitis and itchy eyes caused by pollen, especially Japanese cedar pollen.
Staying healthy in Japan
Due to a hot and humid climate that gives favorable conditions to bacteria, food poisoning is a common health issue during summer in Japan. Avoid eating food that has been sitting in room temperatures for a long time. It is also helpful to sterilize cutting boards and kitchen towels more often.
Additionally, during the winter, food poisoning through norovirus is common. Please be aware that norovirus is very infectious, with mass outbreaks occurring commonly. In order to prevent infection, wash your hands thoroughly, and cook seafood well. When dealing with vomit or excrement from infected persons, do not touch it with your bare hands, and disinfect dirty floors and tableware to prevent secondary infections.
Japanese summers are known for its high-temperatures and humidity. Feeling fatigued all over the body and loss of appetite are some symptoms of summer heat fatigue, where the body is unable to handle the heat. Summers can be surprisingly severe especially in Tokyo and other urban areas due to the "heat island" phenomenon, which is caused by, among others, exhaust heat from air conditioner outdoor units and heat reflection on asphalt-covered ground. To maintain your energy levels during the summer heat it is recommended to drink plenty of water, to avoid excess intake of cold drinks, to get adequate sleep, and to eat nutritious meals.
If you spend a long time in very hot conditions, you may get dehydrated, which could develop into a life threatening condition. To avoid such heat stroke during summer, it is important to take plenty of water, to use sunshades such as hats and/or parasols when you go outside, to avoid staying too long under the sun, and to avoid hard outdoor exercise during the daytime. Furthermore, hyperthermia can occur indoors, if it is too hot or humid. Use blinds and curtains to prevent direct sunlight, and use fans and air conditioning to manage room temperature.
Many people in Japan today are suffering from pollinosis (hay fever). It is an allergic reaction to the pollen of certain plants and causes symptoms including sneezing, a runny nose, and itchy eyes.
In Japan, as many as about 60 types of plants are known to cause pollen allergy. In Tokyo, common allergy-causing plants and their pollen seasons are as follows:
- Japanese cedar sugi (February - April)
- Japanese cypress hinoki (mid March - early May)
- Rice plant ine (May - mid July / mid August - mid October)
- Ragweed butakusa (mid August - October)
- Artemisia yomogi (mid August - October)
People who are not currently affected by pollen may later develop allergic reactions as a result of constantly inhaling pollen in their daily lives. Japanese cedar (sugi) allergy is most common. In Tokyo, about one in 3.5 people is believed to suffer from sugi allergy.
During the sugi pollen season (February - April), weather forecasts usually provide information about the possible amount of pollen in the air. To avoid becoming allergic to pollen, or to reduce the symptoms, it is important to use masks and/or special eyeglasses to effectively block pollen from getting into your body as much as possible.
If you know you are allergic to pollen, it is advised to get prescriptions for appropriate medication before pollen levels get high. Visit a doctor two weeks before the season starts at the very latest. Ask your doctor if you need to continue taking the medication throughout the season after the symptoms ease; they may quickly come back and be worse if you stop taking the medication in the middle of the season.
Novel influenzas are strains of avian flu that were once prevalent among bird populations. However, due to subsequent contact with humans and swine, they have evolved into something that is now easily spread among people.
Because they possess marked antigenic differences from seasonal strains, and because most of the population lack any immunity to them, the potential for novel influenzas to spread rapidly among the population poses a major risk to public health.
Tips to prevent the infection and spread of novel influenza
The same prevention measures should be taken for any types of flu, whether it is a common seasonal type or a new strain. Frequent hand washing and gargling as well as proper cough manners are believed to be effective for protecting yourself as well as others around you from the spread and infection of influenza.
What are cough manners?
Wear a cold mask if you are suffering from coughing and sneezing.
Cover your mouth and nose with tissue paper or something similar when you cough or sneeze.
Turn your face away from other people when you cough or sneeze.