title: Advances and future directions in HIV surveillance in low- and middle-income countries.
abstract: OBJECTIVE
  To present recent advances in HIV/AIDS surveillance methods in low- and middle-income countries.
  
  
  RESULTS
  From 2001 to 2008, 30 low- and middle-income countries implemented national population-based surveys with HIV testing. Antenatal clinic HIV sentinel surveillance sites in sub-Saharan Africa increased from just over 1000 in 2003-2004 to almost 2500 in 2005-2006, becoming more representative of rural areas. Between 2003 and 2007, at least 122 behavioral surveys in low- and middle-income countries used respondent-driven sampling for surveillance among high-risk populations, although many countries with concentrated epidemics continue to have major sentinel surveillance gaps. Improvements have been made in modeling estimates of number of persons HIV infected, and systems are now in place to measure HIV drug resistance. However, the reliable monitoring of trends and the measuring of HIV incidence, morbidity, and mortality is still a challenge.
  
  
  CONCLUSIONS
  In the past 5 years, there have been substantial improvements in the quantity and quality of HIV surveillance studies, especially in the countries with high prevalence. Further efforts should be made in countries that lack fully implemented surveillance systems to improve HIV incidence, morbidity, and mortality surveillance and to use data more effectively.
authors.affiliation: Centers for Disease Control and Prevention, Global AIDS Program, MS E-30, 1600 Clifton Road Atlanta, GA 30033, USA. TDiaz@cdc.gov
authors.forename: Theresa
authors.initials: T
authors.lastname: Diaz
authors.forename: Jesus M
authors.initials: JM
authors.lastname: Garcia-Calleja
authors.forename: Peter D
authors.initials: PD
authors.lastname: Ghys
authors.forename: Keith
authors.initials: K
authors.lastname: Sabin
mesh_terms: D003906:Developing Countries; D015658:HIV Infections / Q000453:epidemiology* / Q000821:virology; D006801:Humans; D008826:Microbial Sensitivity Tests; D018571:Sentinel Surveillance