Every year more than 1 billion people are affected and 1 million die from small insect bites
By Mark Rostron · April 25, 2014
More than half the world's population is at risk from diseases such as malaria, dengue, leishmaniasis, Lyme disease, schistosomiasis, and yellow fever, carried by mosquitoes, flies, ticks, water snails and other vectors as has been determined by a World Health Organization (WHO) report on vector-borne diseases released on the 2nd of April 2014.¹
But what exactly are vector-borne diseases and how do they originate? In layman's terms 'vectors' are organisms that transmit pathogens and parasites from one infected person (or animal) to another, causing serious diseases in human populations.
Vector-borne diseases are commonly found in tropical and sub-tropical regions and places where access to safe drinking-water and sanitation systems is problematic. Vector-borne diseases account for 17% of the estimated global burden of all infectious diseases. The most deadly vector-borne disease, malaria, caused an estimated 627,000 deaths in 2012. However, WHO reports that the world's fastest growing vector-borne disease is dengue, with a 30-fold increase in disease incidence over the last 50 years.²
It's so serious that not only has WHO released a global campaign to educate people about the threat of vector-borne disease under the title, "Small bite, Big threat", but they also made it the focus of World Health Day which took place recently on the 7th of April 2014.
Who is at risk?
Vector-borne diseases affect the poorest populations, particularly where there is a lack of access to adequate housing, safe drinking water and sanitation. Malnourished people and those with weakened immunity are especially susceptible.
WHO reported in a news release on the 2nd of April 2014 that schistosomiasis, transmitted by water snails, is the most widespread of all vector-borne diseases, affecting almost 240 million people worldwide. Children living and playing near infested water are particularly vulnerable to this disease which causes anaemia and a reduced ability to learn.³
None of us are immune
Environmental changes, a massive increase in international travel and trade, changes in agricultural practices and rapid unplanned urbanisation are causing an increase in the number and spread of many vectors worldwide and making new groups of people, notably tourists and business travellers, vulnerable.⁴
According to a recent report featured in the April issue of International Travel & Health Insurance Journal, the drought from which Singapore, Malaysia and areas of Thailand and Indonesia have been suffering since January of this year will drive up the incidence of dengue fever in those regions. The dryness speeds up the lifecycle of the mosquito that carries dengue, as well as enhancing the replication of the pathogen. According to health experts in the report, cases of dengue have quadrupled of late in Malaysia, reaching approximately 14,000, while the number of cases in Singapore between January and March this year has exceeded 2,600.⁵
What is being done to help contain and end the spread of vector-borne diseases?
Besides all of the localised programs that WHO is running in countries around the world that are most affected by vector-borne diseases, the World Health Day was used as a medium to highlight the serious and increasing threat of vector-borne diseases to locals and expatriates working abroad with the slogan, "Small bite, big threat".
On World Health Day 2014, WHO called for a renewed focus on vector control and better provision of safe water, sanitation and hygiene – key strategies outlined in their 2011 Roadmap for the control, elimination and eradication of neglected tropical diseases, which sets targets for the period 2012-2020.
"Vector control remains the most important tool in preventing outbreaks of vector-borne diseases," says Dr Lorenzo Savioli, Director of WHO's Department of Control of Neglected Tropical Diseases. "Increased funds and political commitment are needed to sustain existing vector-control tools, as well as medicines and diagnostic tools – and to conduct urgently needed research."
"A global health agenda that gives higher priority to vector control could save many lives and avert much suffering. Simple, cost-effective interventions like insecticide-treated bed nets and indoor spraying have already saved millions of lives," says Dr Margaret Chan, WHO Director-General.
"No one in the 21st century should die from the bite of a mosquito, a sandfly, a blackfly or a tick."
What can you do?
To protect yourself against vector-borne diseases it is advised that you sleep with insecticide-treated bed nets over you, carry out indoor residual spraying with special insecticides, wear long sleeved shirts and long pants and use insect repellents such as coils, vaporising mats and aerosols. In addition you may want to talk to your general practitioner before travelling to high risk areas about medication that can help protect you against vector-borne diseases. If you are planning on staying and working in high risk areas for longer periods, you may want to look into an international health insurance plan that will provide cover for treatment should you require it.
1WHO Campaigns, World Health Day2014: Preventing vector-borne diseases
2WHO Campaigns, About vector-borne diseases
3WHO Media Centre, World Health Day 2014: Preventing vector-borne diseases
4Centers for Disease Control and Prevention, World Health Day-Vector-Borne Diseases
5International Travel & Health Insurance Journal, April 2014, Issue 159