How long do measles serum IgM level remains positive?

Updated: Jun 06, 2019
  • Author: Selina SP Chen, MD, MPH; Chief Editor: Russell W Steele, MD  more...
  • Print

Among persons with confirmed measles infection, the seropositivity rate for first samples is about 77% when collected within 72 hours; the rate rises to 100% when collected 4-11 days after rash onset. [33] Although the measles serum IgM level remains positive 30-60 days after the illness in most individuals, the IgM titer may become undetectable in some subjects at 4 weeks after rash onset. False-positive results can occur in patients with rheumatologic diseases, parvovirus B19 infection, or infectious mononucleosis.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!