Abstract Ref Number = APCP34
Tormenting Toxoplasma, Running Rubella, and Cynical Cytomegalovirus: Congenital Infections in Asia-Pacific
Professor of Pediatrics, Nagasaki University Graduate School of Biomedical Sciencies
Three taxonomically variable pathogens, Toxoplasma gondii (an obligate intracellular protozoan), rubella virus (a single-stranded RNA virus) and cytomegalovirus (a double-stranded DNA virus) cause intrauterine infections with similar clinical characteristics. However, they have quite different epidemiological features, depending on lifestyle habits, vaccine promotion and other preventive measures.
T. gondii is transmitted through contact with oocyst-contaminated soil or eating cyst-containing raw or undercooked meats. Seroprevalence of T. gondii varies across Asian countries: high in Indonesia and Malaysia and low in East Asia. Considerable difference in seroprevalence is also observed within Japan, possibly reflecting regional difference in eating habits. Although congenital toxoplasmosis torments us with lifelong sequelae, we can prevent it through awareness-raising activities and administration of spiramycin to infected pregnant women. We established a patients association for congenital toxoplasmosis and congenital cytomegalovirus infection for advocacy, peer supports, and awareness-raising activities.
Rubella virus runs over many countries where rubella-containing vaccine has not been included into national immunization program. Vietnam used to be among those countries. We demonstrated that approximately 30% of pregnant women were susceptible to rubella, and estimated the incidence of congenital rubella syndrome (CRS) per 100,000 live births as approximately 200. By investigating Vietnamese children with CRS, we made two important findings in CRS-associated patent ductus arteriosus (PDA). First, pulmonary hypertension secondary to PDA is a life-threatening risk factor. Second, CRS-associated PDA has morphologically distinct from other PDA, leading to difficulty in catheter-based treatment.
Cytomegalovirus (CMV) is very common and usually harmless while most people get infected with it during childhood. Cynically, however, CMV may cause serious fetal damage if pregnant women get infected with it. In Japan, one in every 300 babies was born with congenital CMV infection. Approximately 20% of them are symptomatic at birth and 10% will develop some sequelae later in their lives; therefore, approximately 0.1% of all live births, corresponding to 1,000 babies annually, are victims of congenital CMV disease. Prompt diagnosis is important, because early therapeutic intervention with antiviral agents will improve their auditory and developmental prognosis. A national research team has been working on development of diagnostic tools, awareness-raising activities, and establishment of therapeutic guideline.