Volume 80, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Entomopathogenic fungi, such as and , are being researched as alternatives to chemical adulticides to control mosquito vectors of malaria and dengue. Two cited concerns of fungal control include conidial viability and risks fungal entomopathogens pose to human health. We measured spore viability of 10 fungal isolates over 26 weeks and found a range of persistence. Three isolates maintained ≥ 50% viability 14 weeks after application. No isolate persisted longer than 1 week. To help assess risk of conidia as potential human allergens, we measured airborne conidia in enclosed environments after simulated biopesticide treatment of . Conidia were detectable immediately after treatment, with concentrations of ~7000/m, decreasing over 48 hours to 500 conidia/m. At most, conidia comprised 2% of total visible particulate matter, falling to 0.1% by 2 days. The implications for viability of biological control of adult mosquitoes are discussed.


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  • Received : 11 Nov 2008
  • Accepted : 12 Feb 2009

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