A Deadly Path: Bacterial Spread During Bubonic Plague

Abstract

Yersinia pestis causes bubonic plague, a fulminant disease where host immune responses are abrogated. Recently developed in vivo models of plague have resulted in new ideas regarding bacterial spread in the body. Deciphering bacterial spread is key to understanding Y. pestis and the immune responses it encounters during infection.

Keywords: Yersinia pestis; bubonic plague; dissemination.

Figure 1. Dissemination of Y. pestis in the Body During Bubonic Plague

(1) Inoculation of Y. pestis (brown rods) into the dermal layer of the skin triggers the recruitment of neutrophils (light green cells with blue nuclei). The dermis (pink) appears bellow the epidermis (brown cuboidal cells). (2) In the dermis, Y. pestis interacts mostly with neutrophils. These cells control Y. pestis proliferation in the dermis but are unable to eliminate infection. (3) Dissemination competent bacteria escape from the skin immediately after inoculation via lymphatic vessels (green) to reach the draining lymph node. (4) Y. pestis colonizes the lymph node at very high rates. (5) The bacteria escape the lymph node compartment into systemic circulation through efferent lymphatic vessels or via blood vessels (red). The questions at the right of the figure summarize areas of the field that need to be explored to obtain a more detailed picture of how Y. pestis disseminates in the body.