Malaria elimination strategies should adapt to changing patterns of infection

April 14, 2013, Lancet

According to Sir Richard Feachem, Director of the Global Health Group at the University of California, San Francisco, USA, and senior author of the study, "The malaria control strategies implemented over the last decade have been highly successful in reducing malaria worldwide. However, these strategies must evolve to respond effectively to the changing patterns of infection in low transmission areas. More sophisticated and targeted approaches to identifying those people who are infected, and responding promptly and effectively, must be put in place. The good news is that these new approaches are being pioneered with great success in countries such as China, Sri Lanka, and Swaziland."*

The authors present country examples showing that when malaria is reduced to low levels, it becomes increasingly concentrated in particular places or communities (hotspots) and in particular groups of people (hot-pops). In Sri Lanka, overall malaria incidence decreased by 99.9% between 1999 and 2011, but the proportion of infections in adult men increased from 54% to 93% over the same period.

Migrant workers appear to be at heightened risk, likely due to their participation in outdoor activities such as forestry, plantation work, and farming. Many low-transmission countries now find that the majority of their malaria cases are "imported", coming from international travellers, migrant workers, and other mobile populations who bring malaria from other high-transmission countries.

This new situation is compounded by the fact that many of these groups most exposed to in low transmission settings are beyond the reach of current health services. "Hard-to-reach populations, including ethnic or political minority groups, are typically impoverished and mobile, often driven to more remote areas by marginalisation, safety concerns, and economic opportunities," say the authors. "They might avoid accessing the health systems because of fear of unwanted attention from government authorities, thus making monitoring and treatment of their malaria difficult."

One solution to this problem is to rethink the typical methods used to control infection, tailoring and targeting them to the groups most likely to contract malaria. Traditionally, malaria control has focused on home-based interventions such as bednets and indoor insecticides that protect women and children. However, the authors suggest that different, occupation-based control methods—such as insecticide treated clothing, or hammocks—could be used to protect these populations.

It is not just the demographics of malaria infection that are changing. Traditionally, the Plasmodium falciparum parasite has been considered responsible for the majority of the global malaria burden, and has therefore been the focus of control efforts. However, successful control of P falciparum in many countries has resulted in an increasing proportion of infections from another malarial parasite, Plasmodium vivax. While P vivax is less likely to lead to death than P falciparum, it is also harder to detect and treat, and therefore more difficult to control and eliminate. For example, in the Solomon Islands, malaria control efforts in the elimination provinces of Isabel and Temotu achieved a greater than 90% reduction in total malaria cases between 2001 and 2011, and the proportion of P vivax infections more than doubled over the same period.

According to Chris Cotter, lead author on the study, "Difficulties in detecting malaria infections in low transmission settings, particularly in these hot-pops who are infectious but might not have symptoms, is a major challenge faced by malaria programmes. Population movement across political boundaries and the resulting importation of malaria makes this challenge even greater. Without effective strategies to identify and target these individuals, malaria elimination may prove difficult in certain areas."*

Allocation of funding for malaria control in future years will play a critical role in addressing these challenges. According to the authors, "Despite the growing importance of imported malaria, the largest international funder for malaria control—the Global Fund to Fight AIDS, Tuberculosis and Malaria— allocates only a small proportion of its malaria funding to multicountry proposals…As countries reduce their burdens, strategies that address the changing epidemiology…need to be developed, validated, and adopted."

Explore further: Eliminating malaria has longlasting benefits for many countries

More information: … (13)60310-4/abstract

Related Stories

Eliminating malaria has longlasting benefits for many countries

February 21, 2013
Many nations battling malaria face an economic dilemma: spend money indefinitely to control malaria transmission or commit additional resources to eliminate transmission completely.

Malaria nearly eliminated in Sri Lanka despite decades of conflict

August 30, 2012
(Medical Xpress)—Despite nearly three decades of conflict, Sri Lanka has succeeded in reducing malaria cases by 99.9 percent since 1999 and is on track to eliminate the disease entirely by 2014.

Creating a new weapon in the fight against malaria

May 8, 2012
Over 200 million people contract malaria each year, and according to the World Health Organization, an estimated 655,000 people died from malaria in 2010.

Australia gives $104 million to fighting malaria

November 2, 2012
(AP)—Australia will spend more than 100 million Australian dollars ($104 million) over the next four years to help reduce deaths from malaria in the Asia-Pacific region.

UN appeals for $3.2 billion to meet malaria goal

April 24, 2012
(AP) -- The global campaign to fight malaria is appealing for $3.2 billion to try to reach the U.N. goal of "near-zero" deaths from the mosquito-borne disease by 2015.

Recommended for you

Flu may be spread just by breathing, new study shows; coughing and sneezing not required

January 18, 2018
It is easier to spread the influenza virus (flu) than previously thought, according to a new University of Maryland-led study released today. People commonly believe that they can catch the flu by exposure to droplets from ...

New approach could help curtail hospitalizations due to influenza infection

January 18, 2018
More than 700,000 Americans were hospitalized due to illnesses associated with the seasonal flu during the 2014-15 flu season, according to federal estimates. A radical new approach to vaccine development at UCLA may help ...

Certain flu virus mutations may compensate for fitness costs of other mutations

January 18, 2018
Seasonal flu viruses continually undergo mutations that help them evade the human immune system, but some of these mutations can reduce a virus's potency. According to new research published in PLOS Pathogens, certain mutations ...

Zika virus damages placenta, which may explain malformed babies

January 18, 2018
Though the Zika virus is widely known for a recent outbreak that caused children to be born with microencephaly, or having a small head, and other malformations, scientists have struggled to explain how the virus affects ...

Study reveals how MRSA infection compromises lymphatic function

January 17, 2018
Infections of the skin or other soft tissues with the hard-to-treat MRSA (methicillin-resistant Staphylococcus aureus) bacteria appear to permanently compromise the lymphatic system, which is crucial to immune system function. ...

Fresh approach to tuberculosis vaccine offers better protection

January 17, 2018
A unique platform that resulted in a promising HIV vaccine has also led to a new, highly effective vaccine against tuberculosis that is moving toward testing in humans.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.