By last week, 26 children under the age of five had died due to complications from Coxsackie B virus infections.

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This year's North American vaccine is made from three viruses: two types of influenza A virus (H3N2 and H1N1) and an influenza B virus.

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It is not known if the Coxsackie B virus grows in the respiratory tract or in the gut -- so no one is sure if it is passed through mucus or feces.

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Cohen took the malaria surface protein used in Ballou's vaccine and fused it to a protein from the hepatitis B virus, creating a harmless particle that looked like a virus to the immune system.

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"There is a very small chance that some patients could have been exposed to the hepatitis B virus, the hepatitis C virus, or HIV, based on practices identified at the facility, " the congressional memo states.

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There are six different sub-types of Coxsackie B, a virus named after the town in New York state in which it was discovered in 1948.

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Baraclude is approved in the United States to treat patients with chronic hepatitis B in adults who have active virus and liver damage.

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Another 60 antivirals have begun clinical trials, aimed primarily at HIV, the virus that can lead to AIDS, and hepatitis B and C.

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