Behavioural Surveillance Surveys - The Wisdom of Whores

the spread of HIV. For this reason, surveys
of behavior among young people are of
special interest in countries with high HIV
prevalence. Even in countries where the HIV
epidemic is sustained by sexual networking
of men and women in the general population,
certain sub-populations, notably sex workers
and their regular clients, may contribute
disproportionately to the spread of the virus.
Focused surveys in these groups may
therefore be justified.
In countries or regions where HIV is
concentrated in defined sub-populations
with higher than average risk behavior, the
bulk of behavioral surveillance should consist
of BSS in these groups. They typically include
some or all of the following: men who have
sex with men, injecting drug users, and male
and female sex workers.
In a concentrated epidemic, the virus may
remain confined to circles of people with
higher-risk behavior because there are few
links between those populations and the
general population. Or links and generalized
risk behavior may exist, but HIV may not
have infected enough individuals to result
in explosive growth. In that case, it may be
just a matter of time before the epidemic
becomes generalized. Determining which of
these situations is the case and designing and
measuring the success of the appropriate
interventions are the key purposes of behavioral
data collection in a concentrated epidemic.
The extent to which HIV spreads from
these sub-populations into a wider population
depends on the sexual links between members
of these groups and members of the general
population. Some groups, notably men who
are frequent clients of sex workers (and who
are frequently associated with mobile
occupations such as transport or defense
work), can act as conduits between those with
high risk and a wider population. These
groups may therefore also be included in BSS,
and the links with different partner types
should be a special focus of attention.
It is recommended that countries with
concentrated epidemics carry out occasional
general population surveys to investigate
links between high and low risk groups.
However general population surveys are
difficult to carry out, and may not be justified
for this purpose alone. Some countries with
concentrated epidemics may therefore choose
to include groups representing people of
average risk in their BSS systems. These
groups serve principally for comparative
purposes, and can provide an early warning
if risk behavior suddenly increases. However
it should be noted where risk behavior is
already rare, very large sample sizes would be
needed to show a significant decrease in risk
over time.
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C H A PTER 3 B EHAV I OR A L S U R V EI L L A NC E S U R V EY S