One photograph posted on the internet showed the 88-year-old Republican politician in bed in hospital, where he was recently treated for bronchitis.

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Not long after he arrived in Boston, he treated an Armenian woman for chronic bronchitis.

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Mr Bush was discharged from hospital on 14 January after a seven-week stay, during which he was treated for a bronchitis-related cough.

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Former US President George H W Bush has been released from hospital two months after he was admitted for a bronchitis-related cough, a family spokesman said.

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Chronic bronchitis estimates are for adults 18 and over who had been diagnosed in 2007, based on national rates (NHIS) applied to county population estimates (U.S. Census).

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His office said he was treated for a bacterial infection in addition to the bronchitis and a cough.

BBC: George H W Bush discharged from hospital

Flu is generally just means taking time off work for most people but certain at-risk groups are prone to developing potentially fatal complications, such as bronchitis and pneumonia.

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