2nd August 2023

Diagnostics

Not all disease presentations follow a predetermined diagnostic sieve, so additional investigations are needed. A thick and thin blood film for malarial parasites from at least two separately timed samples is required to exclude malaria.

Serology tests are available to identify the viral antigen when suspecting ‘FAR Syndrome’ viral infections – presenting with Fever, Arthralgia and Rash – such as Dengue and Zika Virus. Molecular testing, such as PCR, may be available and is ultimately more specific to rule out certain viral pathogens.

Remember that Tuberculosis (TB) is particularly unreliable to culture. If suspecting TB, a ‘GeneXpert’ test is often available and more reliable for diagnosis; this uses PCR to identify conserved regions of the mycobacterial genome alongside genes encoding resistance to anti-TB regimen drugs.