In the global efforts to combat malaria, accurate assessment of the public health burden of the disease and its distribution is central to monitoring, control, and decision-making. In an article published this month in The Lancet found that, the 2010 Malaria World Report released by the World Health Organization (WHO) underestimated global malaria mortality by 50 percent. The study led by Dr. Christopher J L Murray from Institute for Health Metrics and Evaluation (IHME) in Seattle estimated the 2010 malaria mortality to be 1.2 million compared to 655 thousands reported by WHO. The study used subnational population data to analyze trends in malaria mortality from 1980 to 2010. The study also found that there has been a systematic underestimation of global malaria mortality. Some of the limitations cited in the paper were the lack of representativeness and misclassification of deaths in the subnational data due to the variability in intensity of malaria transmission, incompleteness, and inconsistency of surveillance data. In addition, results from time-trend and time-series data analysis, which was used in this paper, can be affected if there is migration within the population under review.
We believe at ICMHD that this raises the problem of how to quantify malaria incidence, prevalence, and mortality when there are very large numbers of people on the move who do not fall within national health registration systems. The 2011 World Development Report estimated that by the end of 2009 there were some 42.3 million people displaced globally as a result of conflict, violence, and human rights violations. Of these, 27.1 million were internally displaced persons (IDPs) while 15.2 million were refugees outside their country of nationality or country of habitual residence. The United Nations and the United Nations World Tourism Organization has projected that by 2020 there will be 50 million environmental refugees and nearly 1.6 billion international tourist arrivals.
These figures make evident the urgency in developing more consistent methods on measuring malaria distribution and identifying populations at risk. The different approaches that have been used in determining malaria incidence, prevalence, and mortality have led to highly variable results. Moreover, many malaria trends analyses rarely factor in migrating populations.
At ICMHD we think that unless the international community is willing to pay more attention to migrants and other people on the move, malaria control efforts will fail.
By Talubezie Kasongo