Infectious Agent Tests: PCR

Tests for infectious agents include two main diagnostic methods — PCR (polymerase chain reaction) and serological studies (ELISA). These methods allow detection of infection pathogens and evaluation of the body’s immune response.

PCR test:
  • A molecular diagnostic method that detects DNA or RNA of the infectious agent in biological material (blood, mucus, urine, swabs, etc.).
  • High sensitivity and accuracy — detects infection at early stages, even with minimal amounts of the pathogen.
  • Used for diagnosis of viral (HIV, hepatitis, herpes, human papillomavirus), bacterial (chlamydia, mycoplasmosis, tuberculosis), and other infections.
  • Results are usually available within a few hours.
  • Preparation depends on the type of biological material: blood is taken fasting, swabs require abstaining from sexual activity and hygiene procedures according to instructions.

Serological test (ELISA):
  • Determines the presence of antibodies (immunoglobulins IgA, IgM, IgG) in the blood produced by the immune system in response to infection.
  • Allows assessment of infection stage: IgM — acute phase, IgG — chronic phase or immunity after vaccination.
  • Used to diagnose urogenital, intestinal, fungal, transmissible infections, viral hepatitis, HIV, and other diseases.
  • Allows evaluation of immune status and treatment effectiveness.

Advantages and features:
  • PCR detects the pathogen itself, which is important for early diagnosis and treatment monitoring.
  • Serological tests show the immune response and help determine the disease stage.
  • Both methods complement each other and are often used together for accurate diagnosis.
  • Test results are interpreted by a physician considering the patient’s clinical picture.

Thus, infectious agent tests by PCR and serology are key tools in modern infectious disease diagnostics, enabling timely pathogen detection and immune response monitoring.



Types of Tests