Evaluating Three Rapid Tests for Dengue in Febrile Patients in a Dengue-Endemic Area

Rapid diagnostic tests have been used mainly when it is not possible to carry out the recommended laboratory tests due to challenges derived from the infrastructure of the state surveillance system and, in the specific case of dengue, due to catastrophic climatic events that prevent the transport of samples. However, the performance of rapid diagnostic tests must be evaluated in the particular context of the population in which they are applied. We aimed to assess three rapid diagnostic tests used in Mexico for dengue diagnosis and epidemiologic surveillance.

We used three rapid diagnostic tests that were compared to the RT-PCR/IgM capture ELISA construct as the gold standard. Additionally, the NS1-only results of the three rapid tests were compared to the RT-PCR test as the standard. A total of 125 plasma samples were randomly selected from febrile patients with suspected dengue who requested care between 2 and 6 days after the onset of fever.

The best-performing test showed a sensitivity of 57.3% and a specificity of 100%. Regarding NS1 detection compared to RT-PCR, the best-performing test has a sensitivity of 84.4% and a specificity of 88.75%.

Although these tests can serve as an alternative to RT-PCR in emergencies, they should always be accompanied by a study that considers the history of predominant infection in the population and the circulation of serotypes.