Greetings from Antelope Valley!

That's where the Varicella Active Surveillance Project has done another nice piece of epidemiology on chicken pox in the post-Varivax era.

The authors showed that whereas there are 85% fewer reported cases of chicken pox since institution of the vaccine, the peak incidence and severity of illness has shifted to older ages. The authors conclude that vaccine-induced immunity appears to wane over time.

They recommend adding a booster. The ACIP made a similar recommendation last June as well.

No surprise there.

No one asked Flea for his opinion when the Varicella vaccine guidelines were being promulgated, but he wouldn't have recommended making this one mandatory. Not because the vaccine sucks (we didn't know that until recently), but because VZV is a relatively benign self-limited disease of childhood.