Former US President George HW Bush has been admitted to a Houston hospital after contracting an infection that spread to his blood, a family spokesman says.

Mr Bush, 93, was admitted to Houston Methodist Hospital on Sunday, a day after a funeral was held for his wife, Barbara Bush, spokesman Jim McGrath said on Monday.

“He is responding to treatments and appears to be recovering,” Mr McGrath said in a statement.

The health scare came a week after the death of his wife Barbara Bush, and a day after the former first lady’s funeral.

Mr Bush, the country’s oldest living ex-president, served a single term in the Oval Office from 1989 through 1993.

He is the father of former Republican President George W. Bush, who served two terms from 2001 through 2009, and former Florida Governor Jeb Bush, who unsuccessfully sought the 2016 Republican nomination for president.

Mr Bush, who has been confined to a wheelchair since developing Parkinson’s disease, has required hospital treatment several times in recent years.

Last April he spent two weeks in the hospital for treatment of pneumonia and chronic bronchitis, and was hospitalised for 16 days in January 2017 for pneumonia.

Mr Bush was also hospitalised in 2015 after falling at home in Maine and breaking a bone in his neck, and spent a week in hospital in in December 2014 with shortness of breath. He spent Christmas 2012 in intensive care for a bronchitis-related cough and other issues.

Former US first lady Barbara Bush, the only American woman to see her husband and son both sworn in as president, died last Tuesday at the age of 92.

After the funeral this week, Mr Bush joined his son for a photo with Hillary and former president Bill Clinton, former president Barack Obama and wife Michelle, and first lady Melania Trump.

Happy funeral goers Laura and George W Bush, Bill and Hillary Clinton, Barack and Michelle Obama and Melania Trump with George HW Bush (front.)

Barbara Bush’s longtime friend, Susan Baker, the wife of former Secretary of State James Baker, described her in a eulogy at her funeral on Saturday as a “tough but loving enforcer” whose 73-year marriage to her husband was a real-life fairy tale.

-with AAP