One of my favourites on this list is Nigeria’s Ato nai ise – “Five and three” (5 + 3 = 8, and “eight” sounds like “AIDS”). I like this for a completely off-topic reason: young Chinese often sign off text messages and e-mails with “88″. In Mandarin, 8 is “ba”, so 88 is “ba ba”, enough like English “bye bye” to make it a quick and cheery farewell.

Back on topic of not being able to talk directly about HIV and the things that spread it, I was at first disappointed by the mealy-mouthed HIV policy trotted out by Zimbabwean opposition party Movement for Democratic Change. If you were playing AIDS bingo, you’d have a full house in no time; it’s chock full of all the usual jargon: empowerment, expanded multi-sectoral responses, gender equity, mobilising stakeholders etc etc. Precious little about sex, nothing at all about the tut-tut issues of intergenerational or same sex relations.

Having said that, the fluffy language does hide some sensible policies: Better services for sex workers, including STI care services. Stronger action on sexual abuse, including for children. More efforts to promote condoms. Compulsory licensing. Spousal housing for public sector workers. And they are at least brave enough to put on the table the things that would be sensible to do but are still political hot potatoes:

Some policy areas have not been fully resolved, and the MDC will continue to ensure informed public debate and dialogue on issues such as partner notification, shared confidentiality, reproductive health education for adolescents, commercial sex workers and prisoners, and the promotion of gender equality in a manner that respects social norms, but that also confronts those that are leading to the spread of the disease impeding its management.

I think that last sentence means: stop men behaving like pigs without turning women into harridans, but I can’t be sure. I think we may need better euphemisms.

Let’s look at the last report UNAIDS issued, in December 2007. Confusingly, it also gave figures for 2007, but they’re not the same as the figures in the new report. The 2007 report revised previous estimates downwards quite a bit because of better data, largely from India. So it’s not fair to compare the numbers with the 2006 report. But we can compare them with the trend data given in 2006. I’ve pulled out the numbers, and here they are:

Yes, new infections have “declined” since their peak of 3.4 million in 1998. But they appear to be up on 2006. That’s probably an artefact of changing assumptions. The people living with HIV at the end of 2007 should be those who were living with HIV at the end of 2006 (33.27) plus those who got infected in 2007 (2.7 million, if you take the new figures), minus the people who died (2.0 million). By my calculations, that makes 33.97 million men and women, sons and lovers, kids and grandparents, accountants and circus performers and sex workers infected with HIV worldwide. So we’re missing nearly a million.

I understand that estimates change as better data become available, of course. I even bothered to read the UNAIDS backgrounder on methodology (pdf). But I’m still having trouble understanding how the arithmetic works on this one. I’m also wondering if it really worth the sweat of publishing estimates so often. Does the world really need a 50 page report in December 2007, and then another 357 pages seven months later, giving different figures for the same year? Is the marginal increase in accuracy worth the confusion and crushing report fatigue that I’ve heard from so many journalists?

If yes, it would be nice to have the differences explained. Perhaps more cogently than this explanation, which is given in the report: “Even though the HIV prevalence stabilized in sub-Saharan Africa, the actual number of people infected continues to grow because of ongoing new infections and increasing access to antiretroviral therapy.” Besides contradicting the headline statement that prevention is working in heavily-affected countries (i.e. Africa), this is arrant nonsense. Prevalence is the percentage of the population infected with HIV at any given time. It is the product of past rates of new infection (i.e. incidence) and death. The relationship between prevalence and “the actual number of people infected” is determined soley by the number of people in the population. If prevalence is stable but the number of people infected is growing, then it means that the population is growing, nothing else.

It’s worrysome too that Zimbabwe is singled out with Rwanda as a up-there-in-lights HIV prevention success story. The Zimbabwean government has been preoccupied with many things lately, but HIV prevention has not been top of the list. Data show that partner numbers have fallen, but anecdote suggests that it’s in large part because of the political an economic turmoil that has beset the country. Watching one’s father being beaten-up by Robert Mugabe’s goons doesn’t exactly put one in the mood for sex. It might make you want to go out and get plastered, and that might put you in the mood for sex, but with inflation at 2.2 million percent, beer drinking is no longer and option for lots of people. UNAIDS has in the past (rightly) suggested that good leadership is a crucial ingredient of successful HIV prevention. By giving the example of Zimbabwe so much prominence, are they now suggesting we should turn our attention to economic meltdown as a way of reducing multiple partnerships and thus HIV? It might work. The only year that we saw a substantial fall in the proportion of men buying sex in Indonesia was in 1998, the year the economy took a swan-dive off a dliff.

This kind of nit-picking is of course churlish. I sympathise with the writers of reports like this, caught as they are between the need to show that things are going well (so you should keep investing in HIV) and that the situation is dire (so you should keep investing in HIV). In truth, the key issue is not whether there are 2.5 or 2.7 million new infections. It is that somewhere between two and three million people are still getting infected every year with a completely preventable disease that we are spending over 10 billion dollars a year on. That’s a scandal that no amount of report-writing has been able to change.

I dressed for the occasion.
Put my cute fanny in lace nickers,
Gave my breasts some serious gravity (EJ Win always
says wear new, matching underwear on important days,
that’s why she got me stuff from Bravissimo)
But my name was not there: Not on the voters roll,
where it had been 5 years ago. Vanished. Disappeared.
My name was not there.

He points out several situations where HIV prevalence could be expected to rise, for “good” reasons. Obviously, the longer people survive with HIV, the more people there will be living with HIV at any one time. So yes, increased access to life-prolonging medicine can be expected to result in a rise in HIV prevalence. Does that mean lower prevalence is a “bad” thing? Not necessarily.

The cries of victory from Zimbabwe are based on prevalence rates among pregnant women aged 15-24. HIV prevalence among women in this age group has fallen by more than a quarter in urban areas from 2000 to 2006. Rates seem to have drifted downwards in rural areas too, but not significantly. Could this be, as Tim posits, because more people are dying more quickly? It is possible, of course, but by restricting the analysis to women under 25 the chances of that are limited. Even in rural areas with exceptionally limited health services, people with HIV live a median of between nine and ten years. You’d have to have a truly massive deterioration in general health to see much of an impact of reduced survival in people under 25.

Tim speculates that lower prevalence may be the result of outmigration. But this only works if there is a selective outmigration of HIV-infected people (and in this case a selective outmigration of HIV-infected women aged 15-24, which seems unlikely).

Could prevalence be falling because there are fewer new infections? In other words because HIV negative people are actually less likely than before to be having unprotected sex with someone who is already infected, and who is highly infectious? Possibly. People could be having no sex at all, or no unprotected sex at all, but that wouldn’t account for any changes we see among pregnant women, because they have by definition had unprotected sex.

Could young women be less likely to be having sex with someone infected? Yes, for example if young girls drop their sugar daddys in favour of sex with boys their own age or younger, since those boys are far less likely to be infected than the older men who can provide nice meals, visits to nightclub and units for the cellphone, as well as HIV infection. Could new infections be falling because young women are less likely to be having sex with someone infectious? Yes, if access to antiretorvirals is expanding and adherence is good, because good treatment regimes lower viral load, and that lowers infectivity in the positive partner.

If new infections are falling because uninfected people are less likely to be having sex with infectious people, it still begs the question: is that the result of prevention programmes, or of other factors such as a “personal witness” effect, as Tim suggests? I think the question is a somewhat spurious — it’s just not possible to disentangle the effects. But lets look for a moment at “personal witness”.

Do people change their sexual behaviour if they see a lot of people around them dying of AIDS, which they know is the result of a sexually transmitted virus? It is very plausible. It seems to have happened among gay men in rich countries, and among men and women in Uganda. Do people change their sexual behaviour if they see a lot of people around them dying, but believe the deaths are the result of poverty, witchcraft, post-colonial malevolence or any of the other things that have been hinted at as causes of AIDS, things that allow people not to think about sex? That seems less plausible. I don’t know what proportion of AIDS-related deaths in Zimbabwe have been recognised as being the result of people’s sexual choices and behaviours, but if the proportion is small (as it is in neighbouring South Africa, for example), the witness effect is unlikely to be large.

My own suspicion is that lower prevalence in Zimbabwe is indeed the result of the country’s economic implosion. Not because of outmigration or reduced survival, but because men can no longer afford to support several women, and older men can no longer afford to buy the things that younger women want in exchange for sexual favours. I’m not the only one who thinks this. Craig Timberg wrote a nice story about it in the Washington Post some months ago.