Both children had a fever and cough in late March, and one child vomited.

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About 18.6 million adults and 6.7 million children have hay fever, according to 2004 reports by the National Center for Health Statistics.

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No one has reported sick so far, but five staff whose children are running a fever have been asked to work out of their homes.

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It is understood there has been a higher rate of fever in young children following a second injection.

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Children were also treated for fever and diarrhea.

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Other studies have suggested hay fever was less common among children living on farms.

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Some strains of the bacteria can cause severe diarrhoea, abdominal cramps and fever, and can cause fatal kidney failure in children.

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About 20% of these children had temperatures under 100.4, or below the cutoff for fever, the surveys showed.

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Of children who were brought to the clinic because parents thought they had a fever, most of them had been tested with a home thermometer.

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If you have symptoms for under 48 hrs, there are antiviral medications (Tamiflu and Relenza) that may reduce the duration of symptoms including fever, as well as potential complications (pneumonia, otitis media in young children).

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Among those children who did catch the illness, those taking supplements were more resistant to the disease and suffered fewer fever episodes.

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