The German Association of Pediatricians urged parents to consult a pediatrician immediately when an infant's body temperature rises to 38 degrees Celsius, noting that the rectal measurement method is the most effective way to measure temperature. The association explained that fever in infants can indicate various illnesses, ranging from mild, such as urinary tract infections and gastrointestinal infections, to serious conditions like pneumonia and meningitis. Medical consultation is necessary if the child refuses to eat or drink, or if they experience vomiting, diarrhea, rashes, or febrile seizures.