Old is Gold: Why microscopy is still the Golden standard for malaria diagnosis

As a contribution towards this year’s World Malaria Day, HUMAN highlights the use of microscopy – a WHO & CDC recommended Golden standard – for malaria diagnosis.

The use of microscopes for malaria diagnosis has been around for more than a century.

Beyond this microscopy is one of the most important procedures for diagnosis and control of malaria in countries and rural areas with low resource settings and lacking laboratory infrastructure. According to the latest WHO “World Malaria report”, the number of patients tested by microscopic examination increased from 188 million in 2012 to 197 million in 2013, with India accounting for over 120 million slide examinations [2, 3].

Despite the availability of a plethora of Rapid Tests and PCR techniques, why is microscopic examination of stained thick and thin blood films still considered to be the golden standard in malaria diagnosis?

Microscopy offers distinct advantages that include:

• Definitive identification of infecting species
• Identification of mixed infections based on key morphological differences within the Plasmodium species
• The most accessible method for parasite quantitation
• Useful for monitoring the drug efficacy for treatment
• Serves as a reference for assessing other diagnostic tools
• Requires little infrastructure
• Inexpensive
• Results in 20-60 min without a need to send the sample to a central laboratory
• Capillary blood from a simple finger prick is sufficient
• Slides can be stored long term for referencing

Malaria is preventable and curable if treated promptly. The key is an accurate early diagnosis.

Microscopy is accurate and provides that early diagnosis. But it is crucial to have a highly trained staff to process and analyze the slides in order to have the correct diagnosis. Therefore the WHO has established external quality control guidelines for malaria microscopy, especially benefitting regions that lack trained staff or training institutions [1].

 “Malaria Microscopy Quality Assurance Manual”

HUMAN’s Microscopy line

References

1.World Health Organization, Malaria Microscopy Quality Assurance Manual, Version 1. World Health Organization.

2.World Health Organization, WHO Global Malaria Programme: World Malaria Report: 2014. 2014, World Health Organization.

3.World Health Organization Web site, WHO Global Malaria Programme: World Malaria Report: 2013. 2013, World Health Organization.