The Link Between Nosema
In Honey Bees And Neonicotinoids


A number of studies have highlighted the relationship between neonicotinoid pesticides and mortality (death) in honey bees due to Nosema:

  • Cédric Alaux et al: Interactions between Nosema microspores and a neonicotinoid weaken honeybees (Apis mellifera) – Published 2009; Environmental Microbiology.
  • Cyril Vidau et al: Exposure to Sublethal Doses of Fipronil and Thiacloprid Highly Increases Mortality of Honeybees Previously Infected by Nosema ceranae - Published 2011; PLoS ONE
  • Jeffery S. Pettis et al: Pesticide exposure in honey bees results in increased levels of the gut pathogen Nosema – Published 2011; Naturwissenschaften.
  • Judy Y. Wu et al: Honey bees (Apis mellifera) reared in brood combs containing high levels of pesticide residues exhibit increased susceptibility to Nosema (Microsporidia) infection; Published January 10 2012; Journal of Invertebrate Pathology. 

The EFSA Panel on Plant Protection Products - EFSA Journal 2012; 10(5):2668 also commented:

“Indeed, it has been shown that low levels of some pesticides may have synergic actions with diseases such as Nosema. Finding diseases in test colonies, which were healthy before the experiment, and not finding such diseases in control colonies, can imply a synergic effect of pesticides and diseases”.

Manufacturers themselves provide key information in their marketing literature which may well suggest the findings of the scientific papers above are very significant.

Marketing Literature From Bayer CropScience Admits:
Neonicotinoid Imidacloprid kills a social insect by hampering its ability to deal with pathogenic fungi

The following quotes from the leaflet for Bayer CropScience's product, Premise 200SC suggest that by hampering the termite’s ability to groom itself, this ultimately kills it, because it means the insect cannot clean away harmful fungal spores it comes into contact with via the environment. 

Termites, like honey bees, are superorganisms, and live in vast colonies.

”Low doses of Premise 200SC such as the edge of the Treated Zone, disorientate the termites and cause them to cease their natural grooming behaviour.  Grooming is important for termites to protect them against pathogenic soil fungi.  When termites stop grooming, the naturally occurring fungi in the soil attack and kill the termites.  Premise 200 SC makes fungi 10,000 times more dangerous to termites.  Nature assists Premise in giving unsurpassed control.  This control is Premise 200SC plus Nature.” 

”Premise 200 SC is a systemic insecticide which acts as a contact and stomach poison.  When termites come in contact with this non-repellent product in the treated zone, the stop tunnelling, stop feeding, grooming and they become disoriented, they will be infected by soil fungi and die”. 

”The termite are susceptible to disease and fungi found in soil.  A principle part of their defence system is their grooming habits, allows the termites to get rid of the fungal spores before these spores germinate and cause disease of death.  Premise 200SC interferes with this natural process by lowering defence to nature’s own weaponry.” 


An interesting point from the Bayer CropScience literature, is that death of the termite colony is not immediate, rather, it takes about 3 months.  Their brochure “The Secret Life Of Termites” tells us that after treating an area:

"termites disappeared within a week or two from soil monitors immediately outside the structure, and after three months all termite colonies attacking these structures were eliminated. After two years of monitoring since treatment, not one of these colonies has recovered".

Further information:  How do neonicotinoids work?