World Malaria Day 2017 by Florence Chinyere IMO

The World Malaria Day is one of the eight official public health campaigns currently marked by the World Health Organization (WHO) along with World Health Day, World Blood Donor Day, World Tuberculosis Day, World Immunization Week, World No Tobacco Day, World Hepatitis Day and World Aids Day.

One may wonder why the World Malaria Day is celebrated and remembered considering the effect of Malaria in sub-Sahara Africa where over three million people are still at risk of malaria as reported by World Health Organization (WHO). This day is an occasion to highlight the need for continued investment and sustained political commitment for malaria prevention and control.

It is estimated that by 2020, there will be about 40% reduction in malaria cases and deaths. To speed progress towards these global targets, WHO invites malaria affected countries and their development partners to boost investments in malaria prevention and also appealing to member countries for greater funding for the development, evaluation and further development of new tools as massive investments in malaria prevention will propel countries along the path to elimination as well as improving maternal child birth.

In 1897, Dr Ronald Ross discovered the link between mosquitos and malaria transmission. The intent was to raise the awareness about malaria and how it can be prevented.

Mosquito control strategies have made a huge impact on lessening the burden of malaria in endemic countries. Over 150 million long lasting insecticidal bed nets and in door spraying have been distributed in most affected regions especially in sub-Sahara Africa coupled with improved testing and treatments , such as anti-malaria drugs Artemisinin  as well as encouraging indoor spraying as control measures for combating anopheles mosquitos .

 

Mosquito is a major public health issue not only in the developing countries but also in the west, were they have been incidents of outbreak of Zika virus which mosquitos are the sole vectors.  According to the WHO, after the discovery and effective use of residual insecticides in the 1940s, large-scale and systematic control programmes succeeded in bringing most of the important mosquito-borne diseases under control in many parts of the world. As a matter of facts  Aedes Aegyptus was virtually eliminated from the Americas. By the late 1960s, most mosquito-borne diseases were no longer considered to be major public health problems outside Africa.

As so often happens in public health, when a health threat subsides, the control programme dies. Resources dwindled, control programmes collapsed, infrastructures dismantled, and fewer specialists were trained and deployed. The mosquitoes – and the diseases they transmit –roared back with a vengeance. They returned to an environment with few defences left intact.  Previously successful control programmes were replaced by the reactive space spraying of insecticides during emergencies, a measure with high visibility and political appeal but low impact unless integrated with other control strategies.

Over time increase in population, construction activities and low political will have continued to weaken the capacity to effectively control mosquito breeding. Another issue was the increasing resistance of mosquitos to insecticides.  All these have brought back cases like dengue outbreak which almost eradicated in many parts of the world.

Experts are of the opinion that if countries cannot defend themselves against disruptive and recurring outbreaks of a well-known disease like dengue, what hope is there that mosquito control will help stop Zika?

Mosquito control is complex, costly, and blunted by the spread of insecticide resistance. Few developing countries outside sub-Saharan Africa have dedicated well-funded programmes for mosquito control. Moreover, some control measures are not readily accepted by the public.

What is therefore needed is an integrated approach that tackles all life stages of the mosquito and to fully engage communities and neighbourhoods. Although fogging to kill adult mosquitoes provides the most visible evidence that a government is taking action, WHO stresses that the elimination of mosquito breeding sites is the most effective intervention for protecting populations. Fogging, which is recommended for emergency situations only, is most effective when conducted in the hours around dawn and dusk, when mosquito activity is most intense. Measures for personal protection against mosquito bites, including repellents that are safe for use during pregnancy, are also covered.

Taking into consideration the seriousness of the dengue and now the Zika crises and the need for a broader range of control techniques, a WHO Vector Control Advisory Group has evaluated some newer tools, including a genetically modified prototype mosquito submitted for WHO review. For genetically modified mosquitoes, the WHO Advisory Group has recommended further field trials and risk assessment to evaluate the impact of this new tool on disease transmission. Trials previously conducted in the Cayman Islands showed significant reductions in the Ae. Aegyptus population.  The use of mass release of male insects that have been sterilized by low doses of radiation have proven effective as well. When sterile males mate, the female’s eggs are not viable, and the insect population dies out. The sterile insect technique has been successfully used, on a large scale, by the International Atomic Energy Agency and FAO to control agriculturally important insect pests. Some countries affected by Zika are using biological methods as part of an integrated approach to mosquito control. El Salvador, for example, with strong support from fishing communities, is introducing larvae-devouring fish into water storage containers.

Mosquitos aren’t just an outdoor nuisance, they’re a legitimate cause for health concerns. In 2012 there were recorded cases of West Nile virus in the United States, and according to the Centres for Disease Control and Prevention. CDC.

WHO encourages affected countries and their partners to boost the use of current mosquito control interventions as the most immediate line of defence, and to judiciously test the new approaches that could be applied in future?

A variety of mosquito-repelling tools and measures are available. These include:

  • Planting mosquito repellent plants.
  • Elimination of standing water.
  • Use of bed-net impregnated with insecticides