Temperature and the Field Stability of a Dengue Rapid Diagnostic Test in the Tropics

Abstract

The global incidence of dengue has increased significantly in recent decades, resulting in a large public health burden in tropical and subtropical countries. Dengue rapid diagnostic tests (RDTs) can provide accurate, rapid accessible diagnosis for patient management and may be easily used by health workers in rural areas. However, in dengue-endemic areas, ambient temperatures are often higher than manufacturer's recommendation. We therefore evaluated the effect of high temperature over time on the performance of one commonly used dengue RDT, the Standard Diagnostics Bioline Dengue Duo. RDTs were kept in five different conditions (at 4°C, 35°C, 45°C, 60°C, and at fluctuant ambient temperatures in a free-standing hut) for between 2 days and 2 years in the Lao People's Democratic Republic (PDR). RDTs were tested with four control sera (negative, dengue nonstructural protein 1 [NS1], anti-dengue immunoglobulin [Ig] M, and anti-dengue IgG positive). The RDTs had 100% consistency over the 2-year study, despite high temperatures, including in the hut in which temperatures exceeded the manufacturer's recommendations for 29% of time points. These data suggest that the diagnostic accuracy of the SD Bioline Dengue Duo RDT remains stable even after long-term storage at high temperatures. Therefore, use at such ambient temperatures in tropical areas should not jeopardize the dengue diagnostic outcome.

Assessment of diagnostic and analytic performance of the SD Bioline Dengue Duo test for dengue virus (DENV) infections in an endemic area (Savannakhet province, Lao People's Democratic Republic)

“…In resource-poor settings, lateral flow based point-of-care tests (as the SD Bioline Dengue Duo test) may be the only option to investigate those parameters because they do not require expensive technical equipment and are not affected by adverse storage temperature conditions [7]. Here, we assess the analytical and diagnostic sensitivity of this rapid test using sera from patients with a PCR-confirmed DENV infection from an endemic region in Southeast Asia (Savannakhet province, Lao PDR) [8,9].…”

Using Rapid Diagnostic Tests as a Source of Viral RNA for Dengue Serotyping by RT-PCR - A Novel Epidemiological Tool

“…Here we found similar results with good overall agreement between neat serum and FP extraction either loaded with serum or whole blood from patients at Mahosot Hospital. On evaluation under field conditions, 362 patient samples collected on filter paper from Salavan, stored for 1 month at room temperature (18 to 46°C) [ 15 ], also showed good overall agreement of 90.3% between filter paper extraction and neat serum extraction. The extraction technique used has the advantage of being a simple commercial kit, without phenol.…”

“…Dengue RDTs are becoming important diagnosis tools in dengue epidemic management and is the only diagnostic test, when any are available, in provincial hospitals and health centers in Laos. It is expected that their use will be extended into more remote areas [ 15 ]. Therefore, positive dengue RDTs could be, in Laos and elsewhere in rural Asia, appropriate devices for sample storage and easy transportation to higher-level facilities for dengue serotype RT-PCR determination.…”

“…The Standard Diagnostics (SD) Bioline Dengue Duo RDT (SD dengue RDT; Standard Diagnostics, Kyonggi-do, Korea) permits the concomitant detection of dengue NS1 antigen and anti-dengue IgM and IgG antibodies with overall sensitivity and specificity greater than 80% [ 13 , 14 ]. This dengue RDT remained stable at elevated temperature over 2 years storage in Laos [ 15 ]. Dengue RDTs are now used in provincial hospitals and in a few health centers in southern Laos, and are likely to be extended in rural areas.…”

Diagnostic et traitement des viroses émergentes : comment aller de l’avant ?

“…Ces tests ont généralement une bonne spécificité et une sensibilité limitée, mais le nombre de pathogènes pouvant être testés demeure faible pour un coût plus élevé que celui d'un test moléculaire. Ces tests sont généralement stables à température ambiante[13] et peuvent donc trouver leur place sur le terrain en situation épidémique (orientation diagnostique réalisable à partir d'un simple prélèvement capillaire), mais également en appui à la surveillance épidémiologique puisque leur spécificité permet de les intégrer aux dispositifs d'alerte.Le diagnostic indirect (sérologique) des maladies virales émergentes ou ré-émergentes est particulièrement négligé. Sa place dans le diagnostic médical est certes plus modeste que celle du diagnostic direct, mais ces techniques ne doivent toutefois pas être sous-estimées pour plusieurs raisons.…”