Diagnosis Bill Brieger | 30 Apr 2016 03:24 pm
We cannot end malaria for good without addressing flaviviruses
“End malaria for good”, the theme for the 2016 World Malaria Day, presents us with a double challenge. We want to end malaria finally, or eliminate it between 2030 and 2040, but also, ending it will be good for saving lives and improving economies of endemic countries. The challenge arises when we consider whether we will have adequate resources to accomplish the task. As colleagues from the University of California in San Francisco observed, “Sustaining domestic and international funding as malaria burden decreases is a serious concern for most of the eliminating countries.”
One way to guarantee resources is through conserving what we have and only treating people for malaria when they actually have the disease and not some other febrile illness. The advent of malaria rapid diagnostic tests (mRDTs) that can be used at the primary care level, including within the community should have improved our ability to differentiate malaria from other causes of fever. Unfortunately mRDTs do not always guide correct case management. When a febrile patient tests negative, we may not have the ability to do further differential diagnosis. Some causes of fever do not have a direct cure. Therefore if malaria drugs are available through programs like the Global Fund, we are tempted to use them since many front line clinicians feel that, “We must do something for the patient.”
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Flaviviruses pose one challenge. Such choices not only waste scarce resources but may be harmful. A prime example is the recent outbreak of Yellow Fever in Angola. According to the World Health Organization, “The first, ‘acute’, phase usually causes fever, muscle pain with prominent backache, headache, shivers, loss of appetite, and nausea or vomiting,” making it easily confused with malaria. Treating most of these patients with malaria drugs may not cause harm, but 15% go on to develop severe disease including hemorrhaging and death. Proper use of mRDTs, follow-up observation of RDT-negative patients and provision of supportive care that treats dehydration, respiratory failure, and fever, can save lives.
Rapid diagnostic test kits are widely used in India for the diagnosis of dengue infection, but do not feature in African clinics. Without Dengue RDTs, clinicians in Africa may assume that Dengue is a severe form of malaria and treat as malaria even without parasitological laboratory evidence. With suspected Dengue patients increased intake of oral fluids is recommended by WHO along with paracetamol (not aspirin) for fever and pains.
So far the global Zika Virus outbreak has spared Africa of its worst neurological and brain damaging effects. For the current epidemic the U.S. Centers for Disease Control and Prevention inform that, “The most common symptoms of Zika also resemble malaria and are fever, rash, joint pain, or conjunctivitis (red eyes). Other common symptoms include muscle pain and headache.” for which CDC recommends palliative case management.
Like other flaviviruses Chikungunya “causes fever and severe joint pain. Other symptoms include muscle pain, headache, nausea, fatigue and rash,” according to WHO. WHO explains that, “Most patients recover fully, but in some cases joint pain may persist for several months, or even years.
It will be good to end malaria for good, but we must also have the means to detect and manage the other dangerous, life threatening febrile diseases that will be left behind. In the meantime we need to conduct proper differential diagnosis starting with mRDTs so that expensive malaria medicines will be used judiciously and correctly and other febrile illnesses will receive appropriate life-saving care.