Fighting malaria with improved rapid diagnostic tests
Early and accurate diagnosis, coupled with
effective treatment is critical to the care and
control of malaria. Recently developed rapid
diagnostic tests represent an important advance,
but must perform reliably to have an impact.
Dr. Mark Perkins, Chief Scientific Officer at
FIND, agreed to discuss FIND’s role in the
fight against malaria.
A rapid diagnostic test showing positive result for malaria in a
blood sample
What were the main
reasons for adding malaria
to FIND’s portfolio?
FIND seeks to work in areas where diagnostics
can have a big impact on the lives of people in
developing countries, and where making
progress is technically feasible. Malaria is not
only a huge global cause of morbidity and mortality,
resulting in more than 300 million acute
illnesses and at least one million deaths annually,
it is also almost synonymous in the minds
of many with its most common presenting
symptom, fever. Of course, there are many
causes of fever, and as many as two-thirds of
people with fever treated for malaria have
something else wrong with them. Accurate and
early diagnosis is critical to malaria control, and
to targeting often expensive therapy to the right
patients. This is especially relevant with the
powerful new artemisinin combination therapy
(ACT). Without confirmation of cause, overdiagnosis
and mistreatment are common, which
wastes resources, fuels drug-resistance, and
results in much morbidity from undertreatment
of the true cause of illness in many.
FIND has a unique opportunity, in partnership
with the World Health Organization
(WHO)1, and others already active in this
area, to provide mechanisms to increase the
reliability of malaria rapid diagnostic tests
(RDTs), to empower local users to ensure the
quality of the products they are using, and
improve malaria care and control.
How is malaria usually
diagnosed and how would
you describe current testing
methods?
Malaria has been classically diagnosed with
microscopy. Unfortunately, this technology is
relatively complex and cumbersome to implement,
and gives quite variable performance
even with highly experienced microscopists.
Over the past 15 years, RDTs have been developed
that can accurately detect antigens
from the malaria parasites in a fingerprick
blood sample. These tests are much simpler to
use than microscopy and are potentially a
hugely important advance supporting disease
control. Unfortunately, a number of factors,
including poor test stability at high temperatures,
sometimes inadequate manufacturing
control from the large number of companies
making them, geographic variability in target
antigens, and improper storage or use of the
tests, conspire to diminish the reliability of the
tests in practice. This in turn decreases the
confidence of both patient and care-giver in
the test results, so that they may be disregarded
entirely and treatment decisions be made on
clinical grounds only.
Is December 2006 the
official date that malaria
was incorporated into
FIND’s activities?
The announcement was made that FIND
received approval for the project from the
Bill and Melinda Gates Foundation on
December 14. Full activity plans and detailed
project descriptions were completed shortly
thereafter. Additional funds were received
towards the end of 2006 from the Dutch
Ministry of Foreign Affairs to strengthen and
extend the scope of the project.
What projects are being
developed and/or planned?
Can you briefly describe
some primary goals?
The overall goal of the project is to improve
the performance and reliability of tests being
used in the field. This will be achieved in a
number of ways. First, by developing reference
materials that will allow countries procuring
tests, and health care workers using them, to
determine the quality of purchased tests.
Second, by evaluating the performance and
stability of all commercialized tests to help
guide procurement by the public sector. Third,
by developing new reagents that address
geographic variability in malaria antigens and
that show the thermostability needed in tropical
climates. Lastly, we will chart a technical
and business plan towards the development
and distribution of superior assays.
There are currently several projects in the
malaria portfolio at FIND. These are
- a bank of reference materials and laboratory evaluation of existing RDTs;
- clinical evaluation of high-performance RDTs;
- development of a reference molecular test for field use (LAMP for malaria);
- positive control wells;
- novel and thermostable RDT; and
- a business and technical plan for improved RDTs.
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