Forests cover about 30% of the planet, but deforestation is clearing these essential habitats on a massive scale. What is deforestation? Find out the causes, effects, and solutions to deforestation.
In the last couple of decades, the lush rainforest around the remote village of Meliandou in the heart of Guinea has become patchier. Animals, like bats, saw their habitats dwindle and in a quest for survival, they sought refuge in closer proximity to human environments, making the boundaries between species thinner. A hollowed-out tree in the middle of the village became home to a colony of bats.
About 50 meters from the same tree, in the heart of Meliandou, a two-year-old boy named Emile lived with his family. In a matter of days, Emile fell ill with an unknown virus, developed a high fever, and died. Soon the same virus, that scientists now believe Emile got from the bats, took the lives of his sister, mother, and grandmother. The village, surrounded by a ring of forest, unexpectedly became the epicenter of a devastating outbreak that would leave an indelible mark.
Dr. Raman Velayudhan is a seasoned expert in the public health field and a relentless advocate for combating the global threat of mosquito-borne diseases.
Currently at the helm of the Veterinary Public Health, Vector Control, and Environment unit within the Department of Control of Neglected Tropical Diseases at the World Health Organization (WHO), Dr. Velayudhan’s impact is far-reaching.
Climate change and human activity are enabling the spread of mosquito-borne diseases, like dengue fever, to new places. Stanford infectious disease experts and disease ecologists discuss what we know and how communities can protect themselves from these changing disease threats.
One look at Aedes aegypti gives an immediate impression of its menacing nature. The telltale dark and white bands on the mosquito’s legs and other body parts bring a sense of foreboding and hardship. Sleek, silent, and stealthy, Ae. aegypti is the primary vector for several important, debilitating, and sometimes fatal human diseases including dengue, Zika virus, yellow fever, and chikungunya. The species is cause for mounting concern on many levels, as its biology, behavior, and ability to adapt have made Aedes aegypti one of the most pervasive and daunting public health challenges in the modern world.
The first mosquito ever associated with the spread of disease, Ae. aegypti is also the most studied of all mosquito species.1 From its humble beginnings in the African wild to a footprint that spans the globe, this durable and opportunistic insect has become a formidable opponent of vector control efforts worldwide.
The burden of vector-borne diseases (VBDs) is one of public health’s most pressing challenges. VBDs are caused by pathogens such as arboviruses (arthropod-borne virus), bacteria, and parasites that are transmitted to humans and animals through the bites of infected arthropods including mosquitoes, ticks, sandflies, and fleas, among others. According to the World Health Organization (WHO) , “vector-borne diseases account for more than 17% of all infectious diseases, causing more than 700,000 deaths annually worldwide”.
Beyond these broad statistics, attempts to quantify the global burden of VBDs is extremely challenging – for a number of reasons. At the highest level, even “burden” has an underlying complexity in public health terms: burden may refer to the number of cases of a given disease as well as the number of deaths.
Burden can also represent Disability-adjusted Life Years (DALYs), a measure that accounts for the long-term effects of disability among the afflicted, as well as the economic impact of disease from regions and countries all the way down to households and individuals. These economic impacts can be further scrutinized as reduced productivity among the populace, increased healthcare costs, and negative impacts on tourism; all of which can directly affect the GDP and economic growth of local and regional economies. And that’s just the beginning.
Doctor Shinji Kasai’s recent publication on the combined effects of three knockdown resistance (kdr) mutations in Aedes aegypti sparked media frenzy. He demonstrated the causal relationship between specific genes & pyrethroid sensitivity in mosquitoes.
The study improved understanding of insecticide resistance evolution & opened new strategies to control mosquito populations & reduce disease spread. Kasai’s latest paper on super-insecticide-resistant dengue mosquitoes caused a stir in the media, revealing high levels of pyrethroid resistance in field populations.
It would be extremely difficult to calculate, with any high degree of accuracy, the global economic impact of insecticide resistance. For starters, we must consider that insect management plays a pivotal role in a variety of sectors – agriculture, home and garden, forestry, structural applications, and vector control. Analysis of the totality of economic impacts arising from resistance in any one of these sectors quickly becomes a complicated interplay of variables that interact within that given system.
FKMCD hoping to turn the tide in the first major outbreak of dengue since 2010 As the world remains embattled with COVID-19 and the unprecedented …