The baby's parents allowed their pet Monitor lizard to roam the house, and the child is thought to have been infected through contact with its stools.
A bacterium belonging to a salmonella species, which is common in reptiles but rare in humans, was responsible for the baby's illness. Her older sister was infected with another type of salmonella bacterium, which is also found in reptiles.
In a letter in tomorrow's issue of the Lancet, Dr Guy Makin and colleagues from Sheffield Children's Hospital and the Royal Hallamshire Hospital, describe how the baby was admitted to hospital with fever and sickness. Her condition deteriorated and tests confirmed meningitis. Antibiotic treatment was started and the baby was well enough to go home 18 days later.
A report in the same journal in May detailed the case of a young man infected with salmonella by his pet lizards and who lost his job in a food-processing factory.
The risk of salmonella infections from reptiles is well known in the United States, where in the 1970s a federal ban was imposed on the sale of turtles as pets.
Writing in the Lancet Dr Makin and colleagues appealed for parents to be made aware of the health risk posed to their children. "We suggest that health warnings, specifically relating to the unsuitability of these animals as pets in families with young children, become mandatory in the UK."
Dr Makin said it was well known for salmonella infection to give rise to meningitis. "I've not personally encountered a case like this before, but looking at the literature it is obviously widely recognised in the States where there is a much larger population of indigenous lizards," he said.
"There is a particular problem in relation to turtles and rattlesnakes - snakes are eaten by some ethnic groups and this is one way you can be infected. People who have young children should be aware that this is a real risk. I think it would be reasonable to say they shouldn't keep lizards as pets if they have young children."
Monitors are large lizards. Some species grow up to six-foot long, or more.