Two more cases of a new strain of swine flu were confirmed Monday by Pennsylvania officials. Both are connected to an agricultural fair in southwestern Pennsylvania and bring the total number of cases reported to date to four.
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On Friday, the Centers for Disease Control and Prevention reported two infections of the novel influenza A virus. One involved an Indiana boy and the other was a girl from Pennsylvania who had been to the Washington County Fair the week of Aug. 13-20, the same fair attended by those in the two newest cases.
All of those who have fallen ill were children. Those whose illnesses were reported Friday have fully recovered and those whose cases were reported Monday are also recovering, according to a press release from the Pennsylvania Department of Health.
The particular strain hasn't been seen before, Tom Skinner, CDC spokesman, told msnbc.com on Friday.
While the CDC typically sees a few cases a year of (an influenza A virus), usually as result of contact with swine, "what's new is that it has picked up a gene from the H1N1 pandemic strain," said Skinner.
The two children in the earliest reported cases had received flu vaccines in September 2010, which protected against H1N1, but wouldn't protect against the new strain.
In July, the boy was taken to a hospital emergency department with flulike symptoms of fever, cough and diarrhea, where a respiratory test confirmed influenza A (H3). The boy, who has multiple chronic health conditions, was briefly hospitalized. He had not been directly exposed to swine but a caretaker had been in direct contact with swine in the weeks before the boy became ill.
In August, the girl was also taken to a hospital emergency department with similar symptoms and discharged. A few days before she became sick with a fever, cough and lethargy, she reportedly visited an agricultural fair where she was exposed to swine.
The Pennsylvania departments of health and agriculture and the CDC are investigating the cases.
"There's no evidence of sustained transmission from human to human," Skinner said.
Anyone who attended the Washington County Fair and has flu-like symptoms should contact their local health care provider or call 1-877-PA-HEALTH.
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