PetriKey

Virus

HTLV-1

Oncogenic retrovirus, ATLL and HAM/TSP

aych-tee-el-vee WUN

rna-virusretrovirusoncogenict-cellbreastfeedingprovirus

High-yield clue

HTLV-1 is the retrovirus of adult T-cell leukemia/lymphoma (ATLL) and HTLV-associated myelopathy (HAM/TSP).

Overview

The human T-lymphotropic virus type 1, an enveloped RNA retrovirus that integrates as provirus into CD4 T cells and is the classic transforming retrovirus linked to a leukemia and a neurologic syndrome.

Classification

  • RNA virus
  • Enveloped retrovirus (reverse transcriptase)
  • Family Retroviridae, genus Deltaretrovirus
  • Integrates as DNA provirus

Lab & identification clues

  • Serology plus confirmatory testing vocabulary
  • 'Flower cell' lymphocyte morphology concept
  • Tax oncogene transformation concept
  • Provirus integration detection vocabulary

Associations

  • Adult T-cell leukemia/lymphoma (ATLL)
  • HTLV-associated myelopathy / tropical spastic paraparesis
  • Transmission via breastfeeding, sexual contact, and blood
  • Long clinical latency epidemiology

Commonly confused with

  • HIV
  • Epstein-Barr virus

Your notes

Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.

OpenStax: Microbiology 2e organism classification foundationssourceNCBI Bookshelf: Medical Microbiology organism chapterssourceCDC: CDC disease and public-health topic pagessource