After a Parvo or Distemper infection, IgM antibodies appear before IgG antibodies and the ImmunoComb CDV/CPV IgM kit detects antibodies once they start to appear. This is from day 7 to 20 after exposure; ImmunoComb VacciCheck® CDV/CPV/ICH IgG test detects antibodies from day 14 after exposure and onwards.
In addition, significant IgM levels of antibody appear only after the initial exposure to disease, whether it is from infection or vaccination.
When should I Choose the IgM test?
- IgM tests are useful when clinical symptoms exist, at the suspected early stage of a disease and when a disease is suspected to occur for the first time in life. If you need to confirm earlier exposure to disease by an immunological test, then this is the preferred test.
When should I choose the IgG test?
- When an individual presents with clinical signs of disease, with known previous exposure to disease or vaccination and you want to confirm the disease via antibody tests.
Therefore only IgG would be able to determine antibody levels as IgM would not be present in clinically significant amounts.
This is especially true at more advanced stages of disease because antigen or IgM testing will not identify these diseases.
- When you want to determine pre-vaccination immunity status. This may in the case of a dog with no previous vaccination history or has been vaccinated in the past and may now have an insufficient antibody level. In addition for puppies the IgG test can determine exactly when the maternal antibody levels have decreased to a sufficient level so that maternal antibodies will not interfere with initial vaccination.
- When you want to validate immunity status after vaccination.
This procedure is useful to determine efficiency of vaccination and to help to identify cases of failure to mount immune response due to immunodeficiency conditions. For puppies it's obviously important to check at the end of boosters (two weeks after last shot was given) if immunity level has developed as expected.
There is no right or wrong test, it more depends upon what type of circumstance the dog is under and what you are actually trying to achieve as a result of the test.
“The dot ELISA method (ImmunoComb Parvo and Distemper IgM kit) for detecting IgM antibodies to CDV proved useful for screening under disaster conditions. Rapidly available results enable on-site decision making when necessary, and unlike IgG tests in which paired samples are recommended, IgM results for CDV are based on a single test. Tests were cost effective, easy to perform and read, and did not require any sophisticated equipment.”