Transstadial transmission

Pronunciation
/trans-STAY-dee-ul trans-MISH-un/
Category
Disease Ecology

Definition

The persistence and maintenance of a , , or within an through successive developmental stages (stadia), typically from larva to nymph to or between nymphal instars, without requiring reinfection from an external source at each . The pathogen survives the physiological disruption of and remains viable in the new stage.

Etymology

From Latin trans- (across, through) + stadium (stage, phase of development) + transmission

Example

Borrelia burgdorferi, the spirochete agent of , undergoes transstadial transmission in Ixodes scapularis : larvae acquire the bacterium while feeding on infected vertebrate , retain it through the to the nymphal stage, and again through the molt to adulthood, enabling the tick to transmit the during subsequent blood meals at each active stage.

Synonyms

  • stage-to-stage transmission
  • stadial transmission

Related Terms

Usage Notes

Transstadial transmission is distinguished from (passage to offspring via ) and from simple between individuals. The term applies specifically to hemimetabolous and holometabolous insects, , mites, and other with discrete developmental stages separated by . Survival through requires that evade or tolerate immune responses triggered during molting and adapt to changing tissue environments. Not all pathogens capable of infecting a given stage can achieve transstadial transmission; this capability is a key component of competence assessments in epidemiological studies. Some literature debates whether transstadial transmission should be classified as because it involves maintenance within a single individual's developmental lineage, though it does not involve passage to progeny.