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HIV-1 viral load monitoring: an opportunity to reinforce treatment adherence in a resource-limited setting in Thailand
Global Health Sciences Literature Digest
Published August 4, 2009
Journal Article

Wilson D, Keiluhu AK, Kogrum S, et al. HIV-1 viral load monitoring: an opportunity to reinforce treatment adherence in a resource-limited setting in Thailand. Trans R Soc Trop Med Hyg 2009;103(6):601-6.


To develop and describe educational materials regarding viral load (VL) monitoring and antiretroviral therapy (ART)-adherence and to measure the impact of the educational materials on changes to VL


Kuchinarai, a rural district in Thailand with HIV prevalence among women attending antenatal clinics of 2.6% (compared to 1% nationwide).


HIV-infected patients (171 adults and 14 children) who were receiving medical care, including ART and VL monitoring who had their first VL test between August 2006 and December 2007 and a follow-up VL test done by June 2008


The number of undetectable VL test results following results that were previously detectable


VL monitoring and second-line ART became available in 2006. Patients were divided into three groups: those with undetectable VL, those with low detectable VL (>50 and <1000 copies/mL), and those with high VL (>1000 copies/mL). Patients with undetectable VL received VL monitoring every six months. Patients with low detectable VL were offered adherence support and VL testing three months later. Those with high VL and confirmed viral resistance were counseled and had changed to second-line therapy. If there was no resistance, therapy remained unchanged and follow-up VL testing was done in three months.

A visual educational tool that described the three VL categories was developed and modeled after a traffic signal. Each light corresponded to one of the three categories. The definition, possible outcomes, and course of action associated with each of these categories was shown next to the corresponding light. This tool was used in combination with "VL counseling" provided by peer counselors. Patients were provided with pre- and post-VL-test counseling. The purpose of the counseling was to help patients understand the meaning and importance of VL monitoring and the impact of poor adherence on VL levels.


At the time of their first VL test, median time on HAART for adults was 35 months (range 6-62 months) and for children 47 months (range 17-56 months). The initial and follow-up VL tests were undetectable for 116 adults and 13 children. High VL and resistance occurred in four adults and one 12-year-old child who were switched to second-line ART. The remaining 51 patients had at least one VL test that was not undetectable and received the counseling intervention, and in 47 (92%) of these patients, the VL became undetectable following the intervention.


VL monitoring and adherence counseling can be used to promote ART adherence.

Quality Rating

The evaluation of the counseling intervention was done using standard program data. As such, it lacked the scientific rigor associated with research. Because VL can fluctuate for a variety of reasons, the effect of the counseling intervention on VL and adherence cannot be determined. The findings described in the paper, however, suggest a positive effect of the intervention and merit rigorous evaluation in a randomized controlled trial.

In Context

Resistance to ART increases with poor treatment adherence. With the increased use of ART in resource-constrained areas, resistance has emerged.(1,2) The WHO guidelines call for VL monitoring to determine the need to change treatment(3) and also has been used to reinforce adherence.(4.5) With the use of VL as a method of monitoring adherence comes the need to educate patients about VL testing, interpretation and importance of results, and impact on changes in regimens.

Programmatic Implications

The type of educational tool and counseling described in the paper may be useful in other clinical settings in resource-constrained areas. Although changes in VL may be due to factors beyond adherence, discussing the results of VL testing offers an opportunity to address adherence and to assess the extent to which patients have been adherent, and if not, to address methods to improve adherence.


  1. Wainberg MA, Friedland G. Public health implications of antiretroviral therapy and HIV drug resistance. JAMA 1998;279:1977-83.
  2. Boden D, Hurley A, Zhang L, et al. HIV-1 drug resistance in newly infected individuals. JAMA 1999;282:1135-41.
  3. WHO. Antiretroviral therapy for HIV infection in adults and adolescents in resource-limited settings: recommendations for a public health approach. Geneva: World Health Organization;2006.
  4. Coetzee D, Boulle A, Hildebrand K, Asselman V, van Cutsem G, Goemaere E. Promoting adherence to antiretroviral therapy: the experience from a primary care setting in Khayelitsha, South Africa. AIDS 2004;18:S27-31.
  5. Calmy A, Ford N, Hirschel B, et al. HIV viral load monitoring in resource-limited regions: optional or necessary? Clin Infect Dis 2007;44:128-34.