Aug. 27 (Bloomberg) -- Children were 14 times more likely to be sickened by swine flu than adults 60 and older, the age group that is typically the most at risk for influenza, according to a U.S. study of the disease. Children ages 5 to 14 became ill with swine flu, also known as H1N1, at a rate of 147 per 100,000 people, according to the study of 1,557 confirmed illnesses, including seven deaths, in Chicago from April to July, months when the flu virus usually doesnt spread. The findings were reported today by the U.S. Centers for Disease Control and Prevention in Atlanta.
U.S. health officials are planning a vaccination campaign that will focus on those who are disproportionately affected by H1N1, which include children, pregnant women and adults with underlying health conditions. A separate CDC study released today from New Zealand showed swine flu targeted younger people and dominated other virus strains after circulating for just one month during the winter, when influenza is more active.
Like other Southern Hemisphere countries with temperate climates, New Zealand entered its winter season with co- circulation of both seasonal and 2009 pandemic influenza strains, said the authors of todays report, published in the CDCs Morbidity and Mortality Weekly Report. The number of viruses identified as 2009 pandemic influenza rapidly overtook the number identified as seasonal influenza.
In New Zealand, the number of patients with flu symptoms who sought medical attention was 1,518 doctor visits for every 100,000 people from May 3 to Aug. 2, according to the report by the CDC.
New Zealand Cases
The highest concentration of cases occurred in South Auckland, where people went to the doctor with flu symptoms at a rate of 1,308 per 100,000 in a single week, from July 6 to July 12. A weekly rate of 100 to 149 at that time is considered moderate while rates of more than 400 indicate an epidemic, according to the report.
Data for the study was provided by New Zealands Ministry of Health, as well as doctors and nurses involved in the countries flu surveillance system.