Guidelines on surveillance among populations most at risk for HIV

Sentinel sitesSentinel surveillanceSeroprevalencesurveysSerosurveillanceSexually transmittedinfection (STI)Simple randomsamplingSurveillanceSystematic samplingUnlinked anonymoustestingValiditySites at which sentinel surveillance activities take place, including clinics attended by individuals who maynot be representative of the general population but represent groups initially infected or at higher risk forinfection than the general populationA surveillance system that samples populations from facilities or communities for a short period of time ona regular basisSurveys that estimate the HIV prevalence by testing blood for HIV antibodyCollecting blood samples for surveillance. Latent, subclinical infections and carrier states can be detected,in addition to clinical cases. This is especially important in the case of HIV and other sexually transmittedinfections, which often have a long latent period before symptoms become apparent.Diseases that are spread by the transfer of organisms from person to person during sexual contactA sampling method that requires the use of a random number table or other method (for instance,computer-based) to generate random numbers that identify the persons to be included in the sampleThe systematic collection, analysis, interpretation and dissemination of health data on an ongoing basis, togain knowledge of the pattern of disease occurrence and potential in a community, in order to control andprevent disease in the communityA sampling method that consists of randomly selecting the initial patient who meets the inclusioncriteria and then selecting every “nth” (for example, third or fifth) eligible patient thereafter until thepredetermined sample size is reached or the survey period is overIn unlinked anonymous testing, a sample of blood originally collected for other purposes is tested for HIVafter all information that could identify the source of the blood is eliminated from the sample.The degree to which a measurement actually measures or detects what it is supposed to measure38