WASHINGTON:One of the most systematic looks yet at the H1N1 flu pandemic confirms that it is at worst only a little more serious than an average flu season and could well be a good deal milder, researchers said on Monday.

They analyzed data from Milwaukee and New York, two US cities that have kept detailed tabs on outbreaks of H1N1, to calculate a likely mortality rate of 0.048 percent.

"That is, about 1 in 2,000 people who had symptoms of pandemic H1N1 infection died," Dr Marc Lipsitch of Harvard University and colleagues wrote.

Probably 1.44 percent of patients with H1N1 who were sick enough to have symptoms were hospitalized, and 0.24 percent required intensive care, they added.

The findings, published in PLoS Medicine, a Public Library of Science journal, should be reassuring to public health officials and policymakers who worry that a flu pandemic could kill millions and worsen the global recession.

No guarantees

They do not, however, guarantee that H1N1 will not worsen, or that some other, stronger, strain of flu will not emerge.

"We have estimated ... that approximately 1.44 percent of symptomatic pandemic H1N1 patients during the spring in the United States were hospitalized; 0.239 percent required intensive care or mechanical ventilation; and 0.048 percent died," Lipsitch and colleagues wrote.

Health experts agree it is impossible to count precisely how many people have been sickened by H1N1, which was declared a pandemic in June.

Few people are tested, tests are inaccurate and many people only have mild illness. So careful projections give a more accurate picture of a pandemic than actual counts of confirmed illnesses and deaths.

Lipsitch specializes in these sorts of calculations and a global estimate he did in September gave similar projections.

How many cases?

One open question is how many people have actually been infected. The US Centers for Disease Control and Prevention estimated in November that number was 22 million Americans.

Lipsitch's team calculated a potential range of 7,800 to 29,000 deaths.

This compares to seasonal flu, which kills 36,000 people a year and puts 200,000 into the hospital.

"To date, symptomatic attack rates seem to be far lower than 25 percent in both the completed Southern Hemisphere winter epidemic and the autumn epidemic in progress in the United States," the researchers added in their report

In other H1N1 developments:

Israel treats Gazans

Israel says it's treating five suspected swine flu cases from Gaza in hopes of containing an outbreak of the virus in the blockaded Palestinian territory.

The move is a rare loosening of the tight blockade Israel imposed on Gaza after Hamas militants seized the coastal area in June 2007.

Germany sells vaccine

Germany plans to sell more than two million H1N1 vaccinations abroad due to weak domestic demand, the country's health ministry said yesterday.

Only about five percent of the public has been vaccinated, according to Health Minister Philip Roesler. He said he was checking with other countries to see if they needed any of the medicines and that Ukraine had already signalled interest.

The 2.2 million vaccinations are due to be delivered in late December. German states ordered 50 million vaccinations that are due for delivery in several phases until the spring of 2010.

Only about 15 percent of medical professionals in Germany have been vaccinated. Regional states in Germany started the vaccination programme on Oct. 26.

Swine flu deaths so far stand at 86 in Germany.

Vaccine offered to DPRK

The Republic of Korea's president offered yesterday to send swine flu medication to Pyongyang amid reports that the virus killed dozens of people and is spreading fast in the Democratic People's Republic of Korea (DPRK).

The Seoul-based aid group Good Friends said in newsletters on Monday that swine flu broke out in the DPRK last month, and that it had already claimed the lives of about 40 people in the border city of Sinuiju, near China, and seven in the capital, Pyongyang.

The North's state media outlets have remained silent on the reported outbreak.

Yesterday, ROK President Lee Myung-bak instructed the Cabinet to verify the reports and study ways to send swine flu medication to the DPRK without any conditions.