Weed, Mosquito, Virus: The Ecological Triad Shaping Disease Transmission in Kenya

 

Background: Invasive alien plant species offer enormous ecological and public health risks worldwide, with Kenya experiencing some of the most severe consequences. Non-native flora outcompete indigenous species, reducing local biodiversity, agricultural production, and grazing areas, affecting food security and rural livelihoods. Parthenium hysterophorus (Asteraceae), a highly invasive weed, poses considerable concern due to its capacity to alter ecological systems. Climate change exacerbates these difficulties by altering rainfall patterns and temperatures, enabling invasive species to spread and thrive. As a result, these modifications frequently increase mosquito-breeding areas, which exacerbates the transmission of malaria, dengue, and other arbovirus diseases. Female mosquitoes, the primary vectors of these pathogens, require either blood meals or plant-derived sugars, despite the widespread acknowledgment that arboviral illnesses are highly recognized as serious public health concerns, little is known about how invasive plant species affect mosquito populations or arboviral transmission. This study examines the influence of P. hysterophorus on mosquito vector abundance, diversity, and arbovirus dynamics in the Kenyan Rift Valley area.

Methods: Mosquitoes were collected from six villages with varying levels of P. hysterophorus infestation—three heavily invaded and three free from P. hysterophorus. Using a combination of trapping techniques, approximately 50,000 mosquitoes representing 48 species were captured and identified. This comprehensive survey evaluated mosquito abundance and diversity, providing critical insights into the ecological impacts of invasive alien species on arboviral vector populations.

Conclusions: The findings will elucidate the complex interplay between invasive alien plants, land-use changes, and mosquito vector dynamics, shedding light on the mechanisms driving arbovirus transmission. This study will inform precise vector control strategies and deepen our understanding of the ecological impacts of invasive species on public health, including their role in the spread of diseases. This study will not only guide more targeted vector control strategies but also enhance our understanding of the broader ecological and public health impacts of invasive species in Kenya, particularly in disease spread.