Gap?

I bought Max Brook's survival guide a long time ago, but I recently picked it up again and read through it while on vacation. And I know he mentions this, but I just wanted to know what you guys think.
At the begining of the reocorded attacks there is a HUGE gap between recorded possible attacks. If you havent read it a cave was discovered in Africa from the year 60,000 B.C. inside there was a pile of skulls (that had been crushed in), a large pile of ash, and on the wall a cave painting of a human figure, hands raised, with an evil stare, and has a human body in his mouth. This may not be a credible outbreak, but if it is why is there such a big gap between that outbreak and the next one, which occured in 3000 B.C.?

Was the first one not really an outbreak? Was there some way to neutralize the virus for 57,000 years before it was unleashed again? Could this be done again? Or is there just no proof of any more outbreaks that might of occured in this time period?

Just had me wondering, what do you think?