What is the basic information on the parvo b-19 disease and how it relates to women who are pregnant? my sister just lost her baby due to this disease

Parvovirus : Hydrops fetalis which is abnormal fluid collection in fetus body maybe caused by Parvovirus B-19 and can lead to fetal death. Highest risk between 11-23 weeks of pregnancy . If pregnant woman exposed, should check IgG level. If + reassure patient that she is immune. If -, risk small but if infected, follow weekly Ultrasound. Some hospitals perform Cordocentesis and intrauterine transfusions