Changes

===Laboratory Tests===

===Laboratory Tests===

Anti-''Toxoplasma gondii'' antibodies can be deteceted in the maternal circulation from thirty days post-infection. However, in an outbreak of abortions, action may nned to be taken before this point.

Anti-''Toxoplasma gondii'' IgG antibodies can be detected in the maternal circulation from thirty days post-infection and remain increased for years afterwards. This means that for clinical diagnosis, IgG titres must be measured in paired serum samples taken 3-4 weeks apart, and must show at least a four-fold increase in titre³. In an outbreak of disease, this time scale may be too great to be useful. IgM antibodies become apparent sooner after infection and persist for a much shorter time, and so increased IgM titres are consistent with recent infection.

 

IgM antibodies appear sooner after infection than IgG antibodies but generally do not persist past 3 mo after infection. Increased IgM titers (>1:256) are consistent with recent infection. In contrast, IgG antibodies appear by the fourth week after infection and may remain increased for years during subclinical infection. To be useful, IgG titers must be measured in paired sera from the acute and convalescent stages (3-4 wk apart) and must show at least a 4-fold increase in titer.

===Pathology===

===Pathology===