Transwiki approved by: w:en:User:Dmcdevit

This image was copied from wikipedia:en. The original description was:

Life cycle of the various agents responsible for w:en:microsporidiosis.

Description

1. The infective form of microsporidia is the resistant spore and it can survive for a long time in the environment.
2. The spore extrudes its polar tubule and infects the host cell.
3. The spore injects the infective sporoplasm into the eukaryotic host cell through the polar tubule.
4. Inside the cell, the sporoplasm undergoes extensive multiplication either by merogony (binary fission) or schizogony (multiple fission).
5. This development can occur either in direct contact with the host cell cytoplasm (e.g., E. bieneusi) or inside a vacuole termed parasitophorous vacuole (e.g., E. intestinalis). Either free in the cytoplasm or inside a parasitophorous vacuole, microsporidia develop by sporogony to mature spores.
6. During sporogony, a thick wall is formed around the spore, which provides resistance to adverse environmental conditions. When the spores increase in number and completely fill the host cell cytoplasm, the cell membrane is disrupted and releases the spores to the surroundings.
7. These free mature spores can infect new cells thus continuing the cycle.

Obtained from the CDC Public Health Image Library.

Image credit: CDC/Alexander J. da Silva, PhD/Melanie Moser. (PHIL #3411), 2002.

This file is a work of the Centers for Disease Control and Prevention, part of the United States Department of Health and Human Services, taken or made as part of an employee's official duties. As a work of the U.S. federal government, the file is in the public domain.