Luckily, it is rare but should be considered. Most cases of rat bite fever are caused by the bacteria Spirillum minus and Streptobacillus moniliformis, with most cases resulting from the latter bacterium. Death has been reported but antibiotics work quite well. If symptoms develop after a rat bite, seek immediate medical attention. Symptoms you need to watch out for are fever, chills, a rash, a sore throat, and arthritis-like symptoms.
Complications can include endocarditis and pericarditis.
Salmonella can be a problem in laboratory rats and, thus, a potential hazard to laboratory workers. As far as I know, no cases of rat to human transmission from laboratory rats has been reported. Rabies is fairly rare in rodents. It is extremely unlikely that a human can develop rabies as the result of a bite from a laboratory animal. Thus, the antirabies treatment is not indicated unless it is first confirmed in the offending animal.