Swine flu cases decline in US; false H1N1 emails noted

Washington - The number of swine flu cases in the United States has declined slightly for the fifth straight week, but the proportion of deaths from the virus remains "above the epidemic threshold," health officials said Friday. The Centers for Disease Control (CDC) also warned of false emails that offer flu vaccinations but in fact infect computers with malware if readers click on them.

Hospitalization rates continued to be highest in children up to four years old in the week that ended Saturday, the CDC said in its weekly briefing that covered the week ending November 28.

Another 17 flu-related pediatric deaths, in children up to 18 years old, were recorded by the CDC, bringing to 251 the total of confirmed US children's deaths since the epidemic began in April.

The CDC did not say how many adults had died, but noted that the national rate of new infections among all age groups was still above normal seasonal flu levels.

In its warning about the emails, the CDC said the messages urged readers to register on the CDC website, which they claimed was necessary to receive a vaccine.

No such registration is necessary to receive vaccines, which are being distributed mostly by local health departments around the country.

Some health departments, however, have priority groups for shots that include pregnant women, children and adults up to age 24, people who work with children and people with underlying disease such as asthma or diabetes.

Only 25 US states were reporting widespread influenza activity in the last week of November, down from 32 the previous week, the CDC said.