Infectious Disease Compendium

Human Bites


"I done got bit."

Epidemiologic Risks

Human bites more often than not occur when one damn fool drunk male thinks he is Clint Eastwood and punches another damn fool drunk male in the mouth. Then the damn fool drunk male passes out in a corner for 12 hours and wakes up with an infected hand.


Streptococci (esp milleri) + anaerobes + HACEK (Haemophilus species, Aggregatibacter species, Cardiobacterium species, Eikenella species, and Kingella species). Gram negative aerobic rods should not occur unless the dentition is really rasty: rotting black nubs of teeth.

Empiric Therapy

Ampicillin/clavulanate for prophylaxis of uninfected bites. If allergic, who knows. I tend to suggest cephalexin PLUS metronidazole or a quinolone (other than ciprofloxacin) PLUS metronidazole. In place of metronidazole, doxycycline could be used.

If admitted for debridement and needs IV, I tend to suggest a third generation cephalosporins PLUS metronidazole. Alternatives include a carbapenam OR penicillin/beta-lactamase inhibitors OR a quinolone PLUS metronidazole.


Have a very low threshold for sending the patient to a hand surgeon. Infection in the tendon sheaths or the small joints of the fingers can rapidly lead to lots of destruction, disability and lawsuits.

Do not forget vaccines (tetanus).


Dog and cat injures tend to seek care sooner, which is probably why the bites are not as severe at presentation. A dogs mouth is not cleaner than a humans, it does, after all, lick its butt.

Zombie bites? Nothing to do. You will become one yourself, feasting on brains, until a gunshot to the head.

Unless you follow the results of When zombies attack!: Mathematical modelling of an outbreak of zombie infection.