Managing a malaria outbreak

Sometimes when refugees are forced to flee their homes they take refuge in a low-lying area near swamps or a river, so as to have access to water. This puts them in close proximity to vectors of malaria and other diseases. When an MSF team notices a rise in the number of patients presenting with symptoms of fever and chills, the first thing they must do is to establish the diagnosis. If malaria is known to be endemic in the area, this may well be the cause. However, other diseases such as dengue fever and typhoid can present in a similar fashion. The MSF approach is to take a sample of approximately 100 consecutive patients with fever and to perform a blood film examination of them. This means making a finger prick in the patient and putting two drops of their blood on a microscope slide. The slide is then treated with a stain and examined under a microscope. If a significant proportion of the patients are found to have malaria parasites in their red blood cells then this is assumed to be the diagnosis. From then on, all patients with fever will be given presumptive treatment against malaria. The reason that we do not examine the blood of every patient under the microscope is that during an outbreak of malaria there are many cases and this would place too much of a burden on the local laboratory. It might even delay treatment. In terms of preventing deaths it more efficient and effective to make the presumptive diagnosis and give people the treatment they need.