What I love best about this is discussion of Chart Junk that it prompted at Presentation Zen. Read. Go ahead, read. Then tell me if you think the discussion is po-faced or tongue in cheek? And how come nobody picked up on Environmental Graffiti’s true wickedness, the Misleading Headline. As a resident of Ireland who has also spent time in Shanghai, I can tell you that having sex costs exactly the same in both places. Having safe sex, though; aah, that’s a different matter….

Thanks to Peter at Apt for the tip.

Britain and Canada haven’t had such bans (in fact, the US is one of only 13 countries that erects barriers to the HIV-infected — the ban puts it in the good company of such beacons of openness as Libya, Iraq and Saudi Arabia). Have they been flooded with imported HIV?

Some in the loopier fringes of the bloggosphere, would answer with a resounding yes. In sheer numbers, the answer is certainly no. Canada welcomed over 2,400 immigrants that it knew had HIV between 2002 and 2006, according to an immigration official quoted in the Calgary Sun. That’s peanuts when set against the 1.2 million people who flooded into the country in that time. But in fact, it’s not an insignificant proportion of the estimated 58,000 Canadians with HIV (pdf). Overall, Canada estimates that around 12% of people with HIV are from countries, mostly in East and Southern Africa, where HIV is endemic. And they represent 45% of all heterosexually acquired infections in Canada. In the UK, it’s a lot higher. Over four in five heterosexual infections diagnosed in Britain are in people born in sub-Saharan Africa, and we see a similar pattern in Ireland.

We can’t say exactly where people picked up their infection. But if they grew up in Swaziland (where 43% of adults are infected with HIV) but were diagnosed in the UK (where infection rates are less than a hundredth of that), we can take a pretty good guess. In most countries that don’t bar HIV positives, there seems to be a distinction between imported HIV and new infections at home; those are still mostly in gay men and drug users in Britain, Canada and Ireland. The experience of these other countries would suggest that the US is not going to be mowed down by a wave of secondary HIV spreading out from a pebble of infection brought in by immigrants. So change the law, already!

But a lot of the new HIV in Ireland appears to be imported. The HPSC knows the nationality of 120 of the new cases: 42% of them are in people from sub-Saharan Africa. Only 15% of the heterosexually transmitted HIV was in people born in Ireland, compared with well over 50% of newly identified infections in gay men and drug injectors.

Imported HIV is behind the rise in heterosexual infections reported in the UK, too. Headline writers who don’t look carefully at the data tend to seize on the fact that heterosexual HIV is rising in Britain, but in fact 81 percent heterosexual cases diagnosed in Britain are actually air-freighted in, mostly from Africa, while among gay guys, nearly two thirds is acquired at home. This is another indication that we need to look at our information carefully when planning what to do: Ireland, and Britain too, clearly need to keep their prevention programmes focused on the gay men and drug injectors who are at highest risk of getting infected at home.