Combining isothermal recombinase polymerase amplification with lateral flow assay for diagnosis of P. cynomolgi malaria infection

• Published in: PLoS neglected tropical diseases 2023-07, Vol.17 (7), p.e0011470-e0011470
• Main Authors: Rattaprasert, Pongruj, Chavananikul, Chutima, Fungfuang, Wirasak, Chavalitshewinkoon-Petmitr, Porntip, Limudomporn, Paviga
• Format: Article
• Language: English
• Subjects: Acids; Amplification; Analysis; Animals; Anopheles; Anthropogenic factors; Aquatic insects; Asymptomatic; Biology and Life Sciences; Cloning; Deforestation; Dengue fever; Diagnosis; Disease control; Disease transmission; DNA polymerase; Environmental changes; Genetic aspects; Genetic testing; Health aspects; Human diseases; Humans; Infection; Infections; Laboratory animals; Land use; Macaca; Malaria; Malaria - diagnosis; Malaria - parasitology; Medicine and Health Sciences; Mosquito Vectors; Mosquitoes; National parks; Nucleic Acid Amplification Techniques - methods; Nucleotide sequence; Parasites; Plasmodium cynomolgi; Polymerase Chain Reaction; Prevention; R&D; Recombinants; Recombinase; Recombinases; Research & development; Research and Analysis Methods; Sensitivity; Sensitivity and Specificity; Southeast Asia; Specificity; Strip; Thailand; Tropical diseases; Urban development; Urban sprawl; Vector-borne diseases; Wildlife; Wildlife habitats
• ISSN: 1935-2735; 1935-2727; 1935-2735
• DOI: 10.1371/journal.pntd.0011470

Plasmodium cynomolgi is a nonhuman primate parasite that causes malaria in humans and is transmitted by the Anopheles mosquito. Macaques, the natural hosts of P. cynomolgi, are widely distributed in Asia, especially in Southeast Asia. Anthropogenic land-use changes and wildlife habitat reduction due to local environmental changes, deforestation, urban expansion, and construction increased the frequency of human-macaque-vector interactions and facilitated the emergence of zoonotic malaria, causing an exponential increase in the infection rates in this area. Although microscopic tools are the gold standard for malaria diagnosis, they have very low sensitivity. Therefore, disease control and prevention require rapid, sensitive and accurate diagnostic tests. This study aims to develop a diagnostic method using a recombinase polymerase amplification (RPA) combined with a lateral flow (LF) strip method to specifically diagnose P. cynomolgi. Laboratory validation determined the method's sensitivity and specificity compared to the nested PCR method. The lower limit of detection was 22.14 copies/μl of recombinant plasmid per reaction. The combination method represented 81.82% sensitivity and 94.74% specificity compared to the nested PCR. The diagnostic testing developed in this study combines a recombinase polymerase amplification (RPA) and a lateral flow (LF) strip, offering rapid high sensitivity and specificity. Further development of this technique could make it a promising method for detecting P. cynomolgi.