Table of Contents
What is the difference between dengue NS1 and IgM?
NS1 antigen is generally found during Day 1 and up to Day 9 after onset of fever. The detection of anti-NS1 is inhibited if anti-NS1 antibodies produced. Whereas IgM become detectable by Day 3 to Day 5 after onset of illness in primary dengue and by Day 1 to Day 2 after onset of illness in secondary infections.
What is IgM in dengue test?
Detection of Dengue NS1 antigen helps in the diagnosis of current infection within the first week of illness (during the fever phase). Detection of IgM antibody, however, indicates possible current infection or recent infection (can be positive if the infection had occurred within the past 2 to 3 months).
Does NS1 positive means dengue?
A positive NS1 test result confirms dengue virus infection without providing serotype information. A negative NS1 test result does not rule out infection. People with negative NS1 results should be tested for the presence of dengue IgM antibodies to determine possible recent dengue exposure.
Is dengue NS1 test accurate?
The accuracy of the NS1 antigen rapid test is considered high with sensitivity 55\%-82\% and specificity 97\%-100\%. Since the NS1 rapid test aims to detect dengue NS1 antigen, it should be performed within 5 days of onset of fever.
What if IgM is positive and IgG is negative in dengue?
Positive IgM and IgG tests for dengue antibodies detected in an initial blood sample mean that it is likely that the person became infected with dengue virus within recent weeks. If the IgG is positive but the IgM is low or negative, then it is likely that the person had an infection sometime in the past.
What does dengue NS1 negative mean?
What if IgM is negative and IgG is positive?
IgM positive, IgG negative: This suggests infection in the early stages of the disease.
Is it possible to have dengue with a negative IgG and NS1?
For the time being, yes. You haven’t specified NS1 result, so let’s just assume it to be negative as well. In the initial 3–4 days of dengue infection, NS1 is positive. Then it becomes non reactive and IgM is positive. IgM positivity indicates acute infection. Gradually, when infection resolves, even IgM becomes negative and IgG becomes positive.
What is a positive IgM test result for dengue?
Positive IgM: Patients with a positive IgM test result are classified as presumptive, recent dengue virus infections. Patients with negative IgM results before day 8 of illness and absent or negative NAAT or NS1 results are considered unconfirmed cases.
What does a negative NS1 test result mean?
Interpretation of results A positive NS1 test result confirms dengue virus infection without providing serotype information. A negative NS1 test result does not rule out infection. People with negative NS1 results should be tested for the presence of dengue IgM antibodies to determine possible recent dengue exposure.
What is the meaning of ndns1 antigen positive?
Ns1 antigen positive usually means u have dengue infection and it is in very early stages.. Ur igm and igg levels are negative may be because u have tested in very early stages where they have not raised to a level to be detected by blood test.