Hi Dee & all

Apymyiasis

I did not know this myself until a couple of months ago...

The info below is clipped from a private post.
<<
A "myiasis" is the term used for parasitic larvae infesting animals or
people.  When these fly larvae affect bees, it is termed "apimyiasis".
There are a variety of flies that could infest bees:

What you describe could be from the family Sarcophagidae (flesh flies).
These are similar to blowflies but are grey with black thoracic
stripes.  These flies parasitise bees on flowers or may swoop down on
bees at the hive entrance (as you mentioned), depositing newly hatched
larvae in a bee's back every 6 to 10 seconds.  The larva enters the bee
via the spiracles, where it lives in the thorax until it is about 2 mm
in length.  The bee then dies and the larva moves to the abdomen
(possibly the swollen white abdomens you observed on your bees).  The
larva then grows to approx. 8 mm long then leaves to pupate in the
ground (often in front of the hive), emerging as an adult in 6 to 8
weeks.

The book "Honey bee pests, predators and diseases" by Roger Morse and
Kim Flottum is a fantastic resource with regard to bee disease etc.  In
case you are interested, this is the book I got all this info from :)>>


Best Regards & 73s... Dave Cushman, G8MZY
Beekeeping & Bee Breeding Website...
http://website.lineone.net/~dave.cushman