The influenza season is in full force, with an estimated 2.01 million people across the nation seeking treatment during the week ended Sunday, the health ministry warned Friday.

The estimate is 400,000 up from just a week earlier and more than double the 990,000 logged two weeks ago. The number of flu diagnoses tallied since the season began in late December is estimated at 7.48 million, the ministry said.

The average number of flu patients per hospital or clinic shot up to 39.41 last week, up from 28.66 the week before.

The hardest-hit areas include the western prefectures of Miyazaki, Fukuoka, Yamaguchi and Oita, as well as those surrounding Tokyo, such as Saitama, Chiba and Kanagawa.

A total of 7,182 schools were closed fully or partially during the week through Sunday, up from 3,765 the week before, and that number could rise in coming weeks.

The majority were elementary schools, which accounted for 4,187 of the total.

The most prevalent strain of influenza this season is the Hong Kong A-type, but cases of the B-type have recently surfaced, suggesting the nation might need to brace for its spread in the coming weeks, said Michiko Sakane, director of Sakane M Clinic in Tsukuba, Ibaraki Prefecture.

Sakane said the habit of urging people to get checked early — sometimes too early to get a positive diagnosis — has aggravated the situation.

A doctor’s diagnosis is often necessary for students who miss exams to get a second chance and for corporate applications for sick leave. Since many people often rush to get checked right after developing fevers or muscle pain, massive congestion often emerges at hospitals and clinics.

An influenza check will often be negative for the first 12 hours after infection, prompting carriers to spread the virus at school or work, thinking it was a false alarm, Sakane said.

When people do test positive, doctors are quick to prescribe antiviral drugs such as Oseltamivir (brand name Tamiflu), Zanamivir (Relenza) and Laninamivir (Inavir). While the common use of these drugs has probably helped lower the mortality rate among flu patients, it has also meant that people with milder symptoms get the drugs, exposing them to a greater risk of developing drug resistance, Sakane said.

To avoid the flu and to keep it from spreading, she said the most important thing is to rest, rather than go to the hospital.

“The biggest problem is the culture where you cannot rest when you are sick,” she said.

At home, people can keep infections among family members to a minimum by disinfecting hands thoroughly with alcohol and keeping rooms humidified.

Furthermore, Sakane urged the health ministry and the Japan Medical Association, a nationwide group of mostly independent doctors, to work together to make influenza test kits available to the public over the counter, allowing people to test themselves.

“Look at what happened to the pregnancy test kit,” Sakane said. “Before that was made available in drugstores, people had no choice but to visit an OB-GYN doctor. Now people can do the test at home. Likewise, if we can make flu test kits available, it would reduce unnecessary visits to doctors and lower the risks of infection.”

KEYWORDS flu