Nucleic acid testing options for Enteric Fever
PCR and preferably real-time PCR are the 'gold standard' method for NAT diagnostics due to their high sensitivity and specificity. However, they depend on equipment such as thermocyclers which are not commonly available in Cameroonian diagnostic laboratories could be expensive and also slow . The discovery of isothermal methods of amplifying the nucleic acid target in the last two decades has revolutionized the NAT diagnostics by reducing the amplification time and bypassing the need for a thermocycler. Recombinase polymerase amplification (RPA) \cite{Piepenburg_2006} and LAMP \cite{Notomi2000} are the two most popular PCR alternatives that have seen a wide spread application, particularly in rapid, low-cost, point of care (POC) and near-POC diagnostics. LAMP relies on a single polymerase that amplifies DNA at 65C but has complex primer design requirements as well as using up to six primers compared to the two used for PCR. RPA depends on x enzymes including a polymerase, recombinase, single strand binding protein that amplify DNA at 37C.