AUGUSTA – Maine’s agricultural commissioner remained hospitalized Thursday with a blood infection in Havana, Cuba, where he was listed in critical condition at the CIMEQ, or Center of Medical and Surgical Investigations.

Gov. John E. Baldacci spoke briefly with Commissioner Robert Spear, who reportedly said doctors had advised him his condition was too fragile to risk a planned medical evacuation from the Cuban clinic Thursday to the Jackson Memorial Hospital in Miami.

The 62-year-old Nobleboro dairy farmer collapsed in his hotel Tuesday night, according to Baldacci spokesman Lynn Kippax, who said Spear was in Cuba as a follow-up to last year’s successful state trade mission.

The visit resulted in a pledge from Cuba to purchase up to $10 million in Maine farm products, ranging from produce to livestock.

According to Kippax, Spear left Maine for Montreal on Saturday evening, where he was scheduled to catch an early-morning flight to Havana.

Kippax said Spear had apparently had some surgery to remove warts from his hand last week and that it became clear during the course of the weekend trip that his hand was not healing as well as it should have.

Spear felt increasingly ill on Sunday and Monday after arriving in Havana and was discovered on the floor of his room Tuesday evening by another member of the trade mission, according to Kippax.

The governor’s spokesman said Spear’s condition was not believed to be linked with any activity in Cuba. He described the condition as “life-threatening,” adding Spear required dialysis to address kidney function problems.

Spear was originally hospitalized at the Cira Garcia clinic in Havana before officials in Augusta and Washington, D.C., were able to arrange his transfer to the larger and more modern CIMEQ facility.

“They weren’t going to allow him to be moved at first because of the condition he was in, but I think that in everyone’s interest they wanted to get it done,” Baldacci said. “We want to do everything we can. This is serious.”

Although efforts were under way throughout the day Thursday to transport Spear to Miami where he would be met by family members, Kippax said the commissioner felt he would not be well enough to make the trip until sometime today.

“He’ll be [airlifted] out Friday and will get to Miami Friday,” Kippax said. “He has a blood infection, and one of the doctors in Cuba said his condition was ‘fit to travel, but critical.’ Commissioner Spear is conscious and alert. He talked with me and he talked with the governor.”

Ned Porter, deputy commissioner at the state Agriculture Department, assumed management of the office in Spear’s absence and will oversee operations on a day-to-day basis until his return.

A former Republican House member, Spear was named to his current post by former Gov. Angus S. King in 1999.

He was reappointed to the job under Baldacci in 2003 and was expected to remain in the position for at least two years.