Nosema bombycis

fungus

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Last updated

July 1, 2026

Quick Summary

Nosema bombycis is a parasitic fungus belonging to the phylum Microsporidia. It infects host cells, where it reproduces asexually before forming spores.12

A key species, Nosema bombycis, causes the disease p\u00e9brine in silkworms. This infection can affect all stages of the silkworm's life and all its tissues, leading to visible brown spots and the inability to spin cocoons properly. In 1865, Louis Pasteur identified the spores of Nosema as the cause of this disease and recommended sanitation and destruction of infected colonies to control it.1

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Nosema
The species N. bombycis, which causes the epidemic disease pébrine in silkworms, attacks all tissues and all developmental stages from embryo to adult. In advanced infections, small brown spots cover the body of the silkworm. Diseased larvae, which either are unable to spin cocoons or else spin…
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The species N. bombycis, which causes the epidemic disease pébrine in silkworms, attacks all tissues and all developmental stages from embryo to adult. In advanced infections, small brown spots cover the body of the silkworm. Diseased larvae, which either are unable to spin cocoons or else spin…
Read More