Microspordian parasites in honey bees and in other animals by Dr Scott Campbell

I attended the Warwickshire beekeepers county lecture today it was on Nosema and given by Dr Scott Campbell from Exeter University. It was a very enjoyable and informative lecture.

Nosema is a microporidean which is a parasite and is fungi. Its a spore with a store outer coat which is strong enough for it to avoid being killed by various chemicals. The chemicals that people did use one this and other fungicides have been banned. Also oxalic acid may help to kills it.

Its a fungi found i domestic animals like rabbits, in edible Crustaceans like shrimp and lobster its found in fish and in humans. Normally its killed by the immune system however if the hosts immune system is weak, the parasite can take hold and survive.

It has no way of making its own energy so it saps the host of nutrients for it to survive and reproduce. Its a trait it has developed over time.

The spore finds its way into the bee and in normally found in the gut or ventricular it then lets out a tube from within itself and attaches itself to a host cell. The host cell becomes infected with the parasites young, the parasite then replicates with the cell and spreads. Most normal bees can just kill of the parasite however if the bees immune system has been weaken say from another parasite varrora then it can't or had more difficult fighting this new infection.

Nosema has been know about for a while. It was first discovered in 1857 in european silk worms but is probably millions of years old. In 1870 Louis Pasture wrote a book about nosema in silk worms. In 1959 it was found in humans, however in 1985 it made a huge increase in numbers in humans thanks to AIDS. Then by 2010 it was found to be in honey bees and causing serious issues to bees.

Lots of money is  being spent on research on the issues related to nosema and not just to honey bees, it causes problems with fish farmers and other livestock.

Scientist have found that when bees become infected with nosema they need to increase the amount of sucrose they intake. Microspordian have the smallest number of Genoa, it steals everything it needs from its host. Like all parasites it divides and develops to expand it numbers.Scientists have also discovered that they can affect the pheromone production, and alter flight behavior and mortality.

Bees get infected by two types of nosema
Nosema ceranae - first found in bees in china in 1996. It is found in the gut and the the salivary glands. Its 4x2 um in size
Nosema apis - This more common in bees and found in the midgut/ventricular and is larger about 6x3um in size.