On estimating the number of people with known HIV positive status.

OBJECTIVE: In 2014, the Joint United Nations Program on HIV and AIDS (UNAIDS) and partners set the '90-90-90 targets'. Many countries are facing the challenge of estimating the first 90. Our objective was to propose an alternative modelling procedure, and to discuss its usefulness for taking into account duplication. RESULTS: For deduplication, we identified two important ingredients: the probability for an HIV+ person of being re-tested during the period and average number of HIV+ tests. Other adjusted factors included: the false positive probability; the death and emigration probabilities. The uncertainty of the adjusted estimate was assessed using the plausibility bounds and sensitivity analysis. The proposed method was applied to Cameroon for the period 1987-2016. Of the 560,000 people living with HIV estimated from UNAIDS in 2016; 504,000 out to know their status. The model estimates that 380,464 [379,257, 381,674] know their status (75.5%); thus 179,536 who do not know their status should be sought through the intensification of testing. These results were subsequently used for constructing the full 2016 Cameroon HIV cascade for identifying programmatic gap, prioritizing the resources, and guiding the strategies of the 2018-2022 National Strategy Plan and funding request.

Point-of-care CD4 technology invalid result rates in public health care settings across five countries.

BACKGROUND: Since 2010, point-of-care (POC) CD4 testing platforms have been introduced in both urban and rural settings to expand access to testing by bringing diagnostic services closer to patients. We conducted an analysis of routinely collected CD4 testing data to determine the invalid result rates associated with POC CD4 testing. METHODS: We analyzed 981,152 CD4 testing records collected from Alere Pima Analyzers between January 2011 and December 2016 across five countries in sub-Saharan Africa. Routinely collected data and programmatic records were used to determine the rate of invalid test results per month, by facility type, and by operator based on cumulative usage during the study period. In addition, frequency of invalid test types and utilization of control beads were assessed. RESULTS: Across the five countries, 75,530 invalid messages were returned, resulting in an overall invalid result rate of 7.7%. The invalid result rate by country ranged from 6.6% to 11.2%. Invalid result rates were consistent across facility types. Invalid result rates were inversely correlated with operator usage: low volume operators (<50 tests over study period) experienced an invalid result rate of 10.2%, while high volume operators (>500 tests over study period) experienced an invalid result rate of 5.5%. Two invalid result types (exposure position control and reagent control) accounted for nearly 50% of invalid results. Routine data showed that control beads were run on 88.3% of days that the device was used. CONCLUSIONS: Our analysis found that the rate of invalid results was consistent across all types of health facilities, indicating that decentralization of POC CD4 testing to lower level health facilities did not exhibit high invalid result rates or increase cartridge wastage. Additionally, invalid result rates were inversely correlated to operator usage, with high-volume operators experiencing lower invalid result rates than low-volume operators. POC CD4 testing can, therefore, be performed in decentralized national testing programs; however, adequate training, quality assurance, routine monitoring, and ongoing mentorship should also be implemented for success.