In keeping with stereotypes—pushy Americans and reserved Britons—the UK’s updated HIV treatment guidelines, published in July’s Lancet, recommend starting therapy later than the U.S. standard: Brits say begin as CD4 counts fall toward 350; the official Yank yarn is to start at 500.

“The British have always been a bit more conservative about when to start, and for good reason,” said the AIDS Treatment Data Network’s Rich Jefferys, a transplanted Londoner. “Starting treatment is a risk/benefit equation: At what point is someone at enough risk of disease progression that they’ll benefit from it?” With a normal CD4 range  between 400 and 1,200, Jefferys said, an asymptomatic HIVer with 500 CD4s who starts therapy may be overzealous.

The 350 reserved option may be the U.S. import to invest in. After July’s World AIDS Conference, even San Francisco General Hospital’s Dr. Paul Volberding, a leading early-interventionist since AZT, said: “Don’t you suspect we have, if anything, erred on the side of recommending therapy too early? Putting it off is something we need to consider.” Blimey!, Jefferys said. “It’s rather scary that he’s saying that. My hunch is it means he’s seeing some pretty nasty things in his patients.”