OBJECTIVES/SCOPE
The development of an immunochromatographic test for quick detection of malaria preventive medicines (doxycycline, proguanil and mefloquine) in urine is described. The test integration and observed results in ExxonMobil (EM) workplace malaria program are also presented for potential adoption by organizations seeking to improve adherence to malaria prevention in workers operating in endemic locations.
METHODS PROCEDURES, PROCESS
In 2007, EM established a unique partnership with the French Army Biomedical Institute and two biomedical engineering manufacturers to develop a rapid detection test (RDT). Using specific drug antibodies, they created the tests detecting doxycycline, proguanil and mefloquine in urine. After the initial proof of concept in the laboratory setting, the RDTs were tested in malaria endemic locations using urine samples from workers on malaria preventive medicines and laboratory methods were used to confirm the results. Following such validation process and commercial production, the tests were integrated into ExxonMobil’s malaria program with implementation completed in all eligible sites located in endemic areas by 2013.
RESULTS, OBSERVATIONS, CONCLUSIONS
The first tests successfully developed were for proguanil and mefloquine, followed two years later by doxycycline. The RDT validity was tested against the standard laboratory techniques which use High-Performance Liquid Chromatography (HPLC).
Using urine samples collected in Chad and Equatorial Guinea, 100% of the tests detecting the drugs were confirmed by the laboratory method. Reading and reporting issues were identified for the validation of proguanil and mefloquine and subsequently addressed by an improved test user guide.
For doxycycline EM phase, two different RDTs were compared on 99 urine samples and verified with HPLC: 86.9% tested positive by both RDT’s and 91.9% by HPLC. This could be attributed to the detection level set for the RDT. Only 8 samples were truly negative. A further comparison of the strips showed that one had well-marked responses and more stable immunoglobulins for the test component.
As a result of the test development and implementation, 65% of the 32,496 malaria drug prevention compliance tests performed between 2013 and 2016 were conducted by RDTs. They helped further reduce noncompliance rates, keep the number of cases as low as 15 per year and save approximately 1.6 million dollars during that period. Additional benefits are related to having immediate results and opportunity for timely counseling on malaria prevention.
The use of this newly developed rapid test detecting malaria prevention medicines in urine is an additional incentive for malaria chemoprophylaxis compliance. It is affordable, practical and commercially available to help reduce malaria risk and consequences to companies and their non-immune workers going to malaria-endemic locations.
