Last week, an adorable two year-old little girl presented to a local emergency room with a 103 fever. Like most febrile toddlers, she was fussy and mopey. She had no cough, no runny nose, no diarrhea, no rash. Her white count was a bit elevated. No antibiotic was given since Roseola or comparable viral infection was by far the most likely culprit.

She was seen in our office for a recheck the following day. Things were pretty much unchanged. Two days later, we received a call from the hospital that her blood culture was growing a bug. We weren't too alarmed, as most of the time these days, positive blood cultures are due to contamination of the needle with staph from the skin as the sample is taken. We checked with her parents. She was still feverish.

She returned for yet another visit the following day. Still no sign of the Roseola rash. While in the office, we received another call from the hospital that the bug had been identified. Not staph, but rather pneumococcus! It has been years (actually two decades) since we had seen a case.

Pneumococcus is currently the leading cause of bacterial meningitis and pneumonia in children. It also causes ear, sinus, and other less serious infections. Thankfully, the bug had not gone on to cause one of these complications in our little patient. She received an antibiotic injection, and the fever was gone by the following day.

The risk of serious pneumococcus infection can be reduced considerably by immunization with Prevnar-13. This enhanced vaccine, which came on the market two years ago, offers protection against the most common and invasive strains. The vaccine is more painful than most, if not all, the other shots given to small children. The risk of fever of >102F from the vaccine is about 5%.

There's an old saw passed around on hospital rounds: "When you hear hoofbeats, think of horses -- not zebras". When a small child presents with prolonged or high fever, doctors (and parents) should think about viral infections first and foremost. But realize that a few of those fevers will turn out to be a urinary tract infection. And one might just be a pneumococcus zebra.