Former President George H.W. Bush in intensive care

Former U.S. President George Bush visits a tent camp for earthquake survivors on the outskirts of Islamabad on January 17, 2006 in Pakistan. Bush, 81, came as a special envoy for the United Nations to speak with survivors of the October 8 earthquake that killed more than 75,000 people and left another 3.5 million homeless. He had been scheduled to visit the earthquake zone, but helicopter flights to the area were grounded because of bad weather. (Photo by John Moore/Getty Images)

Former President George H.W. Bush, who just buried his wife first lady Barbara Bush on Saturday, is in intensive care, CNN has learned.

“President Bush was admitted to the Houston Methodist Hospital yesterday morning after contracting an infection that spread to his blood. He is responding to treatments and appears to be recovering. We will issue additional updates as events warrant,” spokesman Jim McGrath said in a statement.

Bush was admitted to the hospital on Sunday morning with an infection that led to sepsis, which can be life-threatening, according to a source close to the former President. He was in critical condition, the source said.

The source added that Bush’s blood pressure kept dropping and a couple of times there was serious concern about whether he was going to come through, but that he had been stabilized.

But with Bush’s age, his health and with this infection, this is very serious, the source explained.

The former President’s hospitalization is especially upsetting for his family because it follows so closely on the death of his wife of 73 years last Tuesday. The family had been worried about how he would deal with her death and such an emotional week, according to the source.