[Efficacy of a rapid test to diagnose Plasmodium vivax in symptomatic patients of Chiapas, Mexico].
OBJECTIVE
To evaluate, under laboratory conditions, the sensitivity and specificity of a rapid diagnostic test (OptiMAL), based on immunoreactive strips, to detect Plasmodium vivax infection in febrile patients in Southern Chiapas, Mexico.


METHODS
The presence of parasites in blood samples of 893 patients was investigated by Giemsa-stained thick blood smear microscopic examination (gold standard). A blood drop from the same sample was smeared on immunoreactive strips to investigate the presence of the parasite pLDH. Discordant results were resolved by PCR amplification of the parasite's 18S SSU rRNA, to discard infection.


RESULTS
OptiMAL had an overall sensitivity of 93.3% and its specificity was 99.5%. Its positive and negative predictive values were 96.5% and 98.9%, respectively. Signal intensity in OptiMAL strips correlated well with the parasitemia density in the blood samples (r = 0.601, p = 0.0001).


CONCLUSIONS
This rapid test had acceptable sensitivity and specificity to detect P. vivax under laboratory conditions and could be useful for malaria diagnosis in field operations in Mexico.
González-Cerón
Lilia
L
Centro de Investigación de Paludismo, Instituto Nacional de Salud Pública, Tapachula, Chiapas, México. Igonzal@insp.mx
Rodríguez
Mario H
MH
Betanzos
Angel F
AF
Abadía
Acatl
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D016780:Malaria, Vivax / Q000175:diagnosis* / Q000469:parasitology; D008297:Male; D008800:Mexico; D008875:Middle Aged; D018512:Parasitemia / Q000175:diagnosis; D010966:Plasmodium vivax / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D016053:RNA, Protozoan / Q000032:analysis; D011934:Reagent Strips; D012680:Sensitivity and Specificity; D013997:Time Factors
D016053:RNA, Protozoan; D011934:Reagent Strips