Viral load

from Wikipedia, the free encyclopedia

The viral load ( English viral load ) is the amount of a blood serum , blood plasma , sputum or a throat swab found virus ; she is z. B. given as the concentration of genomes (for DNA viruses) or genome equivalents (for RNA viruses) per milliliter. For many clinically important viruses there are international standard preparations for calibrating the quantitative test procedures. The concentration is given as a uniform, but randomly determined IU ( International Unit ) or IE (International Unit) per milliliter for the respective virus . International units for a specific virus can be converted into genomes or genome equivalents with a fixed factor.

The term viral load originally comes from HIV therapy, in which for the first time the determination of the concentration was decisive for the further course of therapy and initially just the "burden" of cellular immunity with infectious viruses was meant. Over time, the term was partially transferred to the hepatitis B virus and hepatitis C virus . By determining the viral load, patients with insufficient compliance can sometimes be identified. Meanwhile, the term viral load is incorrectly used for any blood concentration of viral pathogens; the term viral concentration is more correct .

The viral load is determined by quantitative methods of detection of the viral nucleic acid , e.g. B. by so-called real-time PCR , in the case of RNA viruses with a preceding reverse transcription . Determining and checking the virus concentration and its course over time (virus kinetics) are an important part of the choice and monitoring of therapy for chronic viral infections and for patients with a weakened immune system due to illness, organ transplantation or genetic reasons .

Individual evidence

  1. ↑ B. Gärtner, JK Preiksaitis: EBV viral load detection in clinical virology. In: Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology. Volume 48, Number 2, June 2010, pp. 82-90, ISSN  1873-5967 . doi : 10.1016 / j.jcv.2010.03.016 . PMID 20395167 .
  2. ^ Roberta M. Madej et al .: International Standards and Reference Materials for Quantitative Molecular Infectious Disease Testing. J. Mol. Diagn. (2010) 12 (2): pp. 133-143 PMID 20075208
  3. ^ GL Wong, VW Wong: Risk prediction of hepatitis B virus-related hepatocellular carcinoma in the era of antiviral therapy. In: World journal of gastroenterology: WJG. Volume 19, Number 39, October 2013, pp. 6515-6522, ISSN  1007-9327 . doi : 10.3748 / wjg.v19.i39.6515 . PMID 24151375 . PMC 3801362 (free full text).
  4. ↑ K. Bonner, A. Mezochow, T. Roberts, N. Ford, J. Cohn: Viral load monitoring as a tool to reinforce adherence: a systematic review. In: Journal of acquired immune deficiency syndromes (1999). Volume 64, Number 1, September 2013, pp. 74-78, ISSN  1944-7884 . doi : 10.1097 / QAI.0b013e31829f05ac . PMID 23774877 .
  5. ↑ H. Amdiouni, L. Maunula, K. Hajjami, A. Faouzi, A. Soukri, J. Nourlil: Recovery comparison of two virus concentration methods from wastewater using cell culture and real-time PCR. In: Current microbiology. Volume 65, Number 4, October 2012, pp. 432-437, ISSN  1432-0991 . doi : 10.1007 / s00284-012-0174-8 . PMID 22767318 .