What We Do

IDPB’s work has always been a critical component for the detection, research and surveillance of emerging and re-emerging pathogens.

This work is particularly important to three main areas in the study of disease:

  • Diagnosis
  • Outbreak investigations and surveillance
  • Understanding pathogenesis (cause and process)

Pathologists and associated scientific teams work to fully understand a disease so that public health professionals can control it, treat it and prevent it.


Reaching a definitive diagnosis for a disease or condition is essential for developing control and prevention measures, as well as understanding the disease process and proper treatment.

Diagnostic techniques in CDC’s Infectious Diseases Pathology Branch (IDPB) include:

  • Gross examination
  • Microscopic evaluation
  • Immunohistochemistry (IHC)
  • Molecular evaluation – PCR and In situ hybridization (ISH)
  • Microbiological methods
  • Ultrastructural study

Learn more about IDPB’s diagnostic techniques.

Outbreak Investigations and Surveillance

Infectious disease pathologists play an important role during disease outbreak investigations and in ongoing surveillance projects.

During an outbreak, making a diagnosis is a crucial part of the laboratory work done to establish the cause of a disease. If the test results are negative or inconclusive (or if tests fail), the diagnosis may rest solely on pathology results. This is often the case with emerging pathogens, which can be difficult to identify.

Results from IDPB can guide the direction of an outbreak investigation entirely.

Pathology is also important to disease surveillance efforts. Surveillance systems monitor the occurrence of disease, and an effective system can control and prevent an outbreak by picking up on early cases.

Pathology methods can be used to speed up monitoring and make the process simpler and more efficient.


Another of pathology’s important contributions to the study of disease is determining pathogenesis, or the process and progression of a disease within its host.

IDPB employs modern molecular technology that can collect information at a cellular level. By doing so, pathologists can help to determine exactly how a disease develops and progresses.

IDPB's Contributions

IDPB has contributed to the identification, diagnosis and pathogenesis knowledge of many emerging infectious diseases and other diseases of public health importance.