On the basis of substantially increased hospitalizations, the H1N1 swine flu outbreak was declared an epidemic by the National Institute of Infectious Diseases on Friday.

According to the NIID, the average number of flu patients per hospital during the week of Aug. 10 to 16 was 1.69. A number of 1.00 or above signals an epidemic.

Most of the flu patients are believed to have the H1N1 strain of type-A flu, the institute said, adding it estimates their number to be about 110,000.

Since early July, swine flu patients have increased in number by 1.7 times each week. Three recently died within the span of five days.

The NIID said the number of patients per hospital exceeded 1.00 in hospitals surveyed by 264 public health centers in 44 prefectures, excluding Hokkaido, Toyama and Kumamoto, indicating the epidemic is increasing in both area and level, it said.

With the first deaths in Japan from the H1N1 virus, there is a renewed sense of anxiety on the streets.

But according to an infectious diseases expert, what may seem a sudden lethal outbreak is only the expected return of the new flu by fall, which the nation has already prepared to deal with by stockpiling the virus-fighting drugs Tamiflu and Relenza.

“This is only the beginning of the first big wave, and it will continue to spread into September and October,” said Norio Sugaya, an infectious diseases expert and head of the pediatrics department at Keiyu Hospital in Kanagawa Prefecture.

“It came slightly earlier than expected, but it’s hardly a surprise,” he added.

From Aug. 15 to Wednesday, the H1N1 strain claimed three lives, in Okinawa, Kobe and Nagoya. All had other previously existing illnesses that are believed to have contributed to their deaths.

The institute said Okinawa averaged 29.60 patients per hospital, followed by Nara Prefecture with 2.96, Shiga Prefecture with 2.48, Fukushima Prefecture with 2.45 and Tokyo with 2.14 per hospital.

Although Okinawa’s tropical climate may help the new virus spread regardless of the season, the situation is worse in even warmer climates, Sugaya said. He pointed to Thailand, where the new H1N1 strain has claimed over 100 lives, many during the summer, and thousands more are infected.

“Since it is a new virus and no one is immune to it, even a small amount of it can make you ill,” Sugaya said. “And it will be worse in midwinter when the virus will increase in number and live longer.”

Globally, there were more than 182,000 confirmed cases of swine flu and nearly 1,800 deaths as of Aug. 13, according to the World Health Organization, which earlier declared an H1N1 pandemic. But the group says that since countries are no longer required to test and report individual cases, the true figures are probably higher.

By mid-August, the U.S. recorded over 7,500 hospitalizations and nearly 480 deaths, according to the government’s Centers for Disease Control and Prevention. In England and Scotland, where the new virus has already spread considerably, there are around 25,000 to 30,000 new cases every week, according to the Health Protection Agency, a nondepartmental public body in charge of health matters in the U.K.

In Japan, there have been 230 hospitalizations so far, according to the Ministry of Health, Labor and Welfare. Since the first swine flu-related domestic deaths, the government has begun urging citizens to take preventive measures, including wearing masks, washing hands and gargling, as it had done when the virus first arrived in May.

But Keiyu Hospital’s Sugaya said such precautions are largely ineffective.

“The virus is not so mild that you can prevent it just by doing those things,” he said. Instead, the government should be looking ahead and publishing estimates of patient numbers and death tolls for the coming months, as in other areas of the world, he said.

“(Government officials have been) slow to react. They say the people have become lax (about swine flu) in recent months, but they have, too.”

The Stockholm-based European Center for Disease Prevention and Control has made a risk assessment for Europe, where in most areas, like Japan, the first major H1N1 wave is expected soon. The center estimates 20 percent to 30 percent of the population will be infected, albeit mildly, most frequently among vulnerable groups such as children and those with underlying chronic medical conditions. They say the hospitalization rate will reach 1 percent to 2 percent by winter, and the fatality rate will be around 0.1 percent to 0.2 percent.

If these statistics are applied to Japan, which has a population of 127 million, the country will see more than 25 million confirmed cases and 1.2 million hospitalizations. There could also be as many as 127,000 deaths, which puts the current toll into perspective, Sugaya said.

But the expert said Japan is better equipped than other countries to protect its citizens because it excels in the distribution of antiviral drugs.

“Compared to other countries, Japan has considerably fewer seriously ill patients, and that is because they give out Tamiflu and Relenza,” he said.

While in other countries these drugs are not widely used, partly due to the cost, Japan has a stockpile large enough to treat 60 million people, and doctors are quick to administer them to virtually all H1N1 patients, he said.

Tamiflu and Relenza are more reliable methods of treating the new flu than a vaccine, which will not be ready by fall and in too short supply to give to all those at risk, Sugaya said.

On Thursday, the health ministry reduced its previous estimate of the number of people who can be treated with the vaccine by the end of the year from 14 million to 13 million. The treatment will start from mid- to late October, a spokeswoman for the ministry’s tuberculosis and infectious diseases division said.

Despite the late and inadequate supply of the vaccine, Sugaya remains confident that Japan will be ready to fight the infections come fall.

“As long as proper measures are taken and Tamiflu or Relenza are administered, Japan is fully equipped to deal with the wave,” he said.

Information from Kyodo added

Woman’s lungs failing

NAGANO (Kyodo) A woman infected with the H1N1 strain of influenza has fallen seriously ill and been placed on a ventilator, the Nagano Prefectural Government said Thursday, a day after the government declared a full-fledged flu epidemic.

Though the woman, who is in her 30s, has no underlying risk factors, her lungs began to fail after she was confirmed infected with the new flu virus Monday, Nagano officials said, adding that she remains conscious.

A resident of Chikuma, she developed a 39.7-degree fever and other symptoms a week ago and tested positive for influenza A on Aug. 14. She was hospitalized Monday as her condition worsened and taken to another hospital Wednesday after failing to improve, they said.

A facility for the disabled she visited confirmed an outbreak of the flu last week, according to the officials.

In Tokushima Prefecture, 39 participants from two groups at an annual Awaodori dance festival held from Aug. 12 through Sunday have tested positive for influenza A. Three of them were confirmed infected with the new flu, the prefecture said, adding that all are recuperating at home.

The epidemic, which health minister Yoichi Masuzoe declared Wednesday after a report of the third death in Japan since Saturday, also began to affect the ongoing campaigns for the Aug. 30 House of Representatives election.

The ruling Liberal Democratic Party asked all its candidates in a written message Thursday to make antiseptics available at campaign rallies, and to ensure their health and that of their campaigners.

Katsuhito Yokokume, a candidate of the Democratic Party of Japan in the Kanagawa No. 11 constituency, failed to attend a gathering Monday, citing a possible infection.