Mead Johnson Nutrition said two tests of samples of its Enfamil Premium Newborn formula found no sign of the bacteria, known as Cronobacter sakazakii. The samples tested were taken from the same lot as the formula given to the baby boy who died, the company said.
The Missouri case prompted retail giant Walmart to pull all cans of the same size and lot number from its shelves last week. Another newborn baby was sickened in Illinois but is recovering from the infection, according to the state health department.
"These new results reaffirm the testing conducted before the batch was made available to retailers and consumers," the company said in a written statement on the results. "Based on both sets of tests, Mead Johnson can say with confidence that Enfamil Premium Newborn formula, like every infant formula the company produces, is safe."
State authorities and the federal Food and Drug Administration and the Centers for Disease Control have been testing similar samples for the bacteria, which the CDC says sickens four to six people a year.
Mead Johnson said it conducted a second round of testing "due to continuing misinformation and confusion in the marketplace."
"The company wanted to reassure consumers -- as quickly as possible and based on rigorous scientific data -- of the safety and quality of all its products," it said.
The company said its findings match those of health agencies that have conducted their own tests. Early indications led authorities to suspect a link to powdered infant formula, but state and federal tests found no Cronobacter, the CDC's Dr. Robert Tauxe said Friday.
"We really don't have evidence that the two infections are related to each other," Tauxe told CNN. "Those two cases that occurred this past month may just be a coincidence.
The agencies are reviewing information about each newborn, including what they ate and where they were, in an effort to trace the sources of the infections.
Cronobacter can cause life-threatening infections in newborns. It's fatal in nearly 40% of cases, according to the CDC, and some of those who survive can be left with severe neurological problems.