Malpighamoeba mellificae
Scientific Beekeeping
Malpighamoeba mellificae (Mm) is an amoebic disease of the malpighian tubules of the honey bee. These tubules are the equivalent of the kidney in man.

These 5 μm × 15 μm‐sized (usual 6-7μm) amoeba often introduce diarrhoea (sometimes referred to as dysentery by beekeepers) to the colony. This leads to weakening or death of the infected bee. Transmission occurs via dormant cysts being transferred during feeding. These cysts develop in the midgut and move on to access and destroy the epithelial walls of the malpighian tubules, They then proliferate and the resultant cysts are found in the faecal deposits where they infect more bees.

Microscopic (x 400) investigation is required to differentiate beween Mm and Nosema which both present with brown / yellow diarrhoea. The grainy circular cysts are larger than the rice shaped nosema spores (Nosema apis 5–7 µm long and 3–4 µm wide). Both Mm and Nosema apis appear to be synergistic and occur most frequently in the spring.

To minimalise reinfection change the frames of the hive and practice good apiary hygiene to prevent spreading disease. Robbing and drifting also cause spread of the disease.

Very little research is conducted around Mm.