25 April 2011
This World Malaria Day our Chief Scientific Adviser, Prof Chris Whitty, shares the progress he has seen in tackling malaria – and why we need to get better at spotting the disease if we are to beat it.
I first saw wards full of malaria patients in a hospital in urban Vietnam as a medical student in the early 1990s – now it is virtually never seen there. Development, and good malaria control, have pushed malaria right back to the fringes of the country.
We know we can prevent and treat malaria, but there is still a lot of work to do. I am painfully aware as we mark this year’s World Malaria Day that I and my colleagues in Africa and Asia will continue to have to treat malaria for many more years, depressingly frequently for patients who arrive so sick they will die. Many thousands of children and pregnant women will never get to healthcare and will die untreated.
The positive news is that almost all of these deaths can be prevented – and in many places this is happening. So what can we do? A lot of the attention, rightly, goes on preventing malaria with insecticide treated bednets and spraying.
As a doctor, however, my first experience of malaria was in patients who by definition had not been protected. Many thousands of children with malaria are dying because they do not get the effective drugs which can treat the disease.
What took me a longer to realise – but has now been shown by studies by doctors across Africa and Asia – is that every day thousands of children and adults who have a serious illness such as pneumonia or meningitis are wrongly diagnosed as having malaria and are therefore given the wrong treatment. Some of these will die of a bacterial disease where widely available antibiotics would have saved them.
For example, in one area in Tanzania where I was working over 90% of children with a fever given antimalarials did not have malaria - but they did have an infection. Making it possible for healthcare workers in Africa and Asia to diagnose malaria properly is a double win. It means that children who are suffering from malaria get an antimalarial drug, and those who have other diseases can be treated for other serious illnesses.
The World Health Organization last year changed its policy to make it clear that it is not enough to treat every child with a fever for malaria – they need a proper diagnosis. This will save lives, and save unnecessary use of anatimalarial drugs as well.
Until recently, diagnosis of malaria relied on examining blood for malaria under a microscope. This remains a good technique but it is difficult to use where there is no electricity, or no skilled staff or equipment. In the last few years a number of rapid diagnostic tests (RDTs) for malaria which are accurate and stable have been developed.
Most of these RDTs look a bit like a pregnancy test – one blue line means the test has worked, two blue lines that the patient has malaria. They are therefore possible for people to use with relatively limited training. In most countries where DFID works only a minority of people with fever get to the kind of clinic or hospital where proper diagnosis using a microscope is possible.
The RDTs can be used anywhere, although just providing new tests is not enough – people also need training. DFID is working to support the Global Fund and others in their efforts to deploy RDTs properly. It is not just in diagnosis that the malaria that there have recently been advances. A major study in the last few months showed deaths in children with severe malaria could be reduced by over 20% by switching to a newer antimalarial drug. As a result, the World Health Organization’s policy has changed just in the last week.
Deaths from malaria have dropped steadily in almost every country I have worked in across Africa and Asia. The situation is so much better than it was even a few years back – but unfortunately there are still countries where the burden of malaria is as high as it always has been, and even in the countries where things are improving thousands of deaths continue to occur every year.
The drugs are better and now we have diagnostic tests that mean that if we use them properly the right people should get them. This is a problem we know we can do something about, and we now have clear evidence that if we do, deaths from both malaria and other diseases will decrease.