PERFOMANCE CHARACTERISTICS AND COST BENEFIT OF THE SD

BIOLINE HIV/SYPHILIS DUO TEST KIT IN ZIMBABWE

Mtapuri-Zinyowera S, Gumbo P, Munemo E, Ncube G, Machiha A, Mangwanya D, Simbi R, Maeka K, Mugabe M, Mupandasekwa S, Sakubani T.

ZIMA CONGRESS – 19-23 Aug 2015VICTORIA FALLS

MANDATES OF THE NMRLTo carryout evaluations and validations of new

diagnostic technologies – rapid tests, POC technologies or conventional machines.

Run disease surveillances – influence policy change

Do diagnostic tests that are routinely carried out in the clinical labs.

Outbreak response. TrainingsQuality assurance – QASI, DTSSupport programs.

BACKGROUNDMTCT of syphilis and HIV can result in severe adverse

pregnancy outcomes and serious illness in infants, including miscarriage, stillbirth, preterm delivery, congenital syphilis, and pediatric HIV infection.

Syphilis and HIV testing of all pregnant women is recommended to prevent MTCT of these infections.

Both the WHO and the Pan American Health Organization have set a goal of elimination of MTCT by 2015.

To accomplish this goal, countries must achieve near- universal testing and treatment of pregnant women.

SD BIOLINE HIV/SYPHILIS DUOStudy design This was a crossectional comparison of two testing strategies, i.e. use of a

combined HIV and syphilis test at a clinic comparing with laboratory enzyme immune assays as gold standards.

Study sites The study sites in the Southern region were Mbare poly clinic, Budiriro poly

clinic and Harare Hospital ANC department. In the Northern region the sites were Mpilo Central Hospital, Khami Clinic, Luveve clinic, Thorngrove Hospital, Mzilikazi clinic, Dulumadzimu clinic and Beitbridge Hospital.

Testing laboratory was the National Microbiology Reference Laboratory.  Inclusion and exclusion criteria The inclusion criteria was ANC pregnant women who would have consented to

be in the study. The exclusion criteria was pregnant women that were critically ill, patients unable or unwilling to provide informed consent or unsuitable

specimens with volumes inadequate for testing.

Objectives1. To assess the operational characteristics of

rapid test, including the ease of use, technical complexity and inter-reader variability.

2. To determine the laboratory-based performance of dual HIV/syphilis rapid diagnostic test (RDT) compared to reference assays.

3. To analyze the cost benefit of the use of a single combined HIV and syphilis test kit compared to using separate HIV and syphilis test kits.

METHODOLOGY – OPERATIONAL CHARACTERITICS241 Pregnant mothers were recruited after

informed consent.Normal rapid HIV testing was done using the

country’s algorithm and results given back.Another was then done using the SD Duo.

METHODOLOGY-LAB BASED PERFOMANCESpecimens were collected from 321 mothers attending 3

clinics in Harare after informed consent – Mbare polyclinic, Budiriro polyclinic and Harare Hospital ANC.

Normal rapid tests were carried out using the normal algorithm then SD Bioline Duo.

Specimens were then tested in the laboratory using EIA assays with the gold standards for HIV being Anilabs (Labsystems Diagnostics Oy, Finland), Vironostika HIV ag/ab (Biomerieux, France) confirming with HIV Blot 2.2 westernblot kit (MP Diagnostics, Singapore).

The reference tests for syphilis were the RPR kit (Lab 21 Health Care Ltd, UK) TPHA kit (AMS, UK).

RESULTS :- INTER-READER VARIABILITY SD color scale

1% ~ 11% : Weak positive 14% ~ 26% : Medium positiveMore than 29%: Strong positive

A total of 241 patients were tested for both HIV and Syphilis in the Matebeland region whereby 63(26%) were HIV positive and 30(12.4%) were RPR positive. In terms of inter reader variability the reader results fell within the same category of positivity according to the SD Bioline grading kit and there was no reader variability as no results among all readers overlapped to the next category of the grades.

HIV RESULTS HIV ELISA(GOLD STANDARD)

SD BIOLINE HIV/SyphilisDuo (HIV testing)

POSITIVE NEGATIVE TOTAL

POSITIVE 37 0 37

NEGATIVE 0 284 284

TOTAL 37 284 321

SYPHILIS RESULTS SYPHILIS (GOLD STANDARD)

SD BIOLINE HIV/SyphilisDuo (HIV testing)

POSITIVE NEGATIVE TOTAL

POSITIVE 3 0 3

NEGATIVE 0 290 290

TOTAL 3 291 294

COST BENEFITIn 2014 the PMTCT programme tested

390,311 pregnant women for HIV and 392 093 were also tested for syphilis calculations for cost benefit were then done.

Cost /test :- HIV test is US$1.00 syphilis test is US$0.75 SD Bioline Duo is $1.50.

COST BENEFIT

Cost benefit of the Duo test is reduced by 14% Saved US$77 327.75. Distribution and storage costs of the SD Bioline Duo test kit is

reduced by half as compared to the current scenario whereby two

kits are used as compared to one kit which tests 2 diseases.

TEST/cost per test NUMBER TESTED

TOTAL COST (US$)

SD DUO

HIV/US$1.00 309311 309 311.00

SYPHILIS/US$0.75 309311 231 983.25

Grand Total 618622 541 294.25 463 966.50

USER FEEDBACK QUESTIONNAIRE18 nurses involved in study – 10 responded.8 (80%) indicated that test was easy to carry out with

2 (20%) said that they had difficult with the colour scale grading system.

70% indicated that it was time saving though challenges would be there if the patient needed only one test.

100% all agreed :-The instructions on the kit were clear. The job aid was essential It was better to use the Duo kit as compared to the

separate kits.

CONCLUSIONThe use of a combined HIV and syphilis point

of care (POC) test allows reduced testing and time in running different assays and the test is also cost effective.

THANK-YOU