Warding off flu infections

As Japan heads into mid-winter weather, the number of influenza cases is rising. The National Institute of Infectious Diseases says that, this year, Japan is approaching a peak in the spread of influenza about three weeks earlier than usual. It is imperative that not only individuals but also businesses and other organizations take precautions to prevent the spread of the seasonal disease.

According to the institute, some 5,000 designated medical institutions across the country reported an estimated 1.39 million influenza cases in the week from Dec. 29 to Jan. 4, and the number jumped to 2.06 million in the week from Jan. 5 to 11. Accordingly the average number of influenza patients at each medical institution increased from 21.36 to 33.28.

When the average number tops 30 in each area, the local public health center is supposed to issue a warning of a large-scale influenza outbreak. At least one such area exists in most of Japan’s prefectures, including Hokkaido and Tokyo. A total of an estimated 4.18 million people have suffered from influenza across the nation so far this flu season.

Most of the influenza detected in the last five weeks is of the A Hong Kong type, which tends to cause serious conditions and even death. It is important not to mistake influenza for an ordinary cold. In the case of influenza, the symptoms include fever, fatigue, chills, muscle pains, diarrhea and difficulty in breathing in addition to the symptoms associated with an ordinary cold such as a sore throat, coughing and a runny nose.

Influenza viruses spread via droplets emitted by coughing and sneezing. After an incubation period of one to five days, the symptoms, especially a high fever of 38 degrees or more, occur quickly. When people develop such symptoms, they should quickly seek medical treatment at a hospital or clinic. They should refrain from relying on self-diagnosis and the use of less effective over-the-counter drugs. When people start taking prescription flu medication, they should stay home for at least five days to prevent the spread of the disease. It is important for flu patients to have sufficient sleep, nutrition and water. The use of a humidifier may keep the room humid enough to prevent the spread of flu viruses.

High-risk groups such as elderly people, infants, pregnant women and people with primary diseases such as diabetes, asthma and kidney disease are likely to develop serious conditions including pneumonia. People aged 65 and older should contact public health centers or medical institutions and receive a pneumonia vaccination.

The most effective way to ward off influenza is to get a flu shot. It is said to take about two weeks for the vaccination to develop immunity in the recipient. The best timing for getting the shot is before the start of the influenza season. Since the season has already set in, people should consult with doctors about the advisability of receiving the flu vaccination, which costs ¥3,000 to ¥5,000.

Apart from the vaccination, people should take such preventive measures as avoiding crowded places, wearing a face mask, frequently washing their hands and gargling, and keeping rooms humid. Although these measures are not panacea, it is important for people to do what they can to minimize the risk. As viruses can spread quickly in crowded office conditions, employers should let workers who have been infected by the flu to stay home for a sufficient period of time to prevent the spread of the infectious disease at the workplace.

  • Joe Kurosu, M.D.

    I have to disagree with the blanket advice that “When people develop such symptoms, they should quickly seek medical treatment…”. Most otherwise healthy adults do not require medical care for influenza. Going to the hospital when you are ill will only increase the chances of giving the virus to someone else and is a waste of one’s precious energy (not to mention healthcare Yen) that is better spent on fighting the virus at home.

    As the CDC says:

    “Most people with the flu have mild illness and do not need medical care or antiviral drugs. If you get sick with flu symptoms, in most cases, you should stay home and avoid contact with other people except to get medical care.”

    The very young and old, and those that have other chronic conditions that place them at high risk, should seek medical care in the early stages. For all others, recuperating in the comfort of your own bed is probably the best strategy.