Increase in Dengue Fever: A health impact associated with climate change

Tue, Aug 09, 2010

Editor: I take this opportunity to update readers about one of the many health impacts, which is exacerbated by climate change – that of an increase in dengue occurrences.{{more}} According to the World Health Organization, dengue fever is the fastest growing vector borne disease in the world, with an estimated 2.5 billion or two-thirds of the population, including the Caribbean region, is at risk.

With a progressive increase in global temperature, it is expected that the mosquito survival time, habitats, as well as maturation and infective periods will be affected. Mosquitoes are expected to get smaller, thus requiring more blood meal, and will be able to transmit more diseases.

During the past two decades, local as well as regional health officials have been monitoring the morbidity and mortality of this disease and concluded that the number of dengue occurrences has been increasing. Based on research done by Caribbean scientists, it has been shown that severe outbreaks often occur one year following an El Nino event. There is yet another interesting anomaly. French Guiana experienced a dengue outbreak in 2009, during the traditional dry season.

Changes in rainfall patterns give rise to situations where there appear to be no major differences between the rainy and dry season. Heavy rainfall events are occurring in the dry season and the rainy season often has some periods where there is little or no rainfall event. This partially explains why countries are experiencing dengue outbreaks during the traditional dry season.

In small island states, such as St. Vincent and the Grenadines, it is extremely important that the populace increase their coping and adaptive capacities, aimed at reducing the human health impacts of climate change, more specifically an increase in dengue occurrences. It is certainly not business as usual.

As the nation experiences yet another rainy season, the issue of dengue fever must be placed on the front burner. It must be remembered that the adult mosquitoes found within our individual dwelling areas may not necessary breed inside the immediate neighborhood, but may be imported. It may just take a few hours’ plane ride for a mosquito to move from another region of the world to this state. The task ahead of us is for all stakeholders to join together towards reducing the health impact caused by climate change and variability. In this case, the control of mosquitoes can be a step in the right direction.

Let us work together with the Ministry of Health, Wellness and the Environment to ensure that the level of dengue occurrences does not constitute a public health concern.

Neri James