A Virginia boy born almost a year ago is the first case of congenital Chagas disease reported in the U.S., according to the CDC.

The boy was delivered by cesarean section at 29 weeks gestation in August 2010 after he was found to have fetal hydrops, the accumulation of fluid in at least two fetal compartments, the agency reported in the July 6 issue of Morbidity and Mortality Weekly Report.

In the second week after birth, his mother – a 31-year-old immigrant from Bolivia – told physicians she had been previously diagnosed with Chagas and testing of the infant revealed evidence of Trypanosoma cruzi, the parasite that causes the disease, which is transmitted to humans by blood-sucking insects.

These insects are often called "kissing bugs" because they tend to bite people on the lips.

The boy is "the first documented congenital transmission of T cruzi in the United States," the CDC reported, adding, "additional, but unrecognized, cases likely exist."

The CDC said the boy's case is a reminder of the need for greater awareness of the disorder among healthcare providers.

The boy was born with ascitic fluid in the peritoneal cavity, pleural effusion, and pericardial effusion, the agency noted, and his physicians carried out a range of tests to discover the cause.

Blood tests for Toxoplasma gondii, rubella virus, and cytomegalovirus were negative, as were genetic tests for cytomegalovirus and enterovirus, a malaria smear, and a hepatitis panel.

Antibodies to herpes simplex virus were present, but cultures and genetic testing for viral nucleic acid were negative.

The boy was treated empirically with acyclovir (Zovirax) and given five days of ampicillin (Principen) and gentamicin (Garamycin) for presumed sepsis.

But testing for the parasite did not take place until the mother told doctors she had been diagnosed with the disease during a previous pregnancy in Bolivia and had not been treated.

T cruzi trypomastigotes -- the extracellular form of the parasite -- were found in a blood smear, serologic tests for antibodies against the parasite were positive, and polymerase chain reaction testing for T cruzi was strongly positive, the CDC reported.

After a 60-day course of benznidazole, the boy's symptoms cleared up and at 10 months repeat testing for the parasite was negative. Benznidazole and nifurtimox, the anti-parasitic drugs used to treat Chagas disease, are not approved in the U.S., but are available through the CDC for use under investigational protocols.

Testing of the mother showed she had Chagas disease, although she had no signs or symptoms and her electrocardiogram was normal.

The incidence of such cases is not well understood, the CDC noted, although an estimate based on home-country prevalence and birth rates among immigrants from areas where Chagas is endemic suggests between 65 and 315 congenital transmissions a year in the U.S.

The agency noted that U.S. obstetrician-gynecologists have "limited knowledge" of the disease, adding increased awareness is needed, especially among those who treat pregnant women from Mexico and South and Central America who might be at risk.

One difficulty, the CDC added, is that congenital T cruzi infection "has no specific clinical signs" and infected newborns may have no symptoms or only very subtle ones.

But "even severe disease might not be recognized because of the lack of defining clinical features and because the diagnosis is not considered," the agency said.

On the other hand, treatment in the first few weeks of life has a cure rate of more than 90%, the CDC reported.

Chagas was at the center of a controversy last month when a tropical medicine specialist called the disease the "new HIV/AIDS of the Americas."

Peter Hotez, MD, dean of Baylor College of Medicine's National School of Tropical Medicine in Houston, wrote in an editorial that there were notable similarities between people living with Chagas and those living with HIV/AIDS.

"Based on the chronic morbidities and high mortalities, the prolonged and expensive treatment courses, the lack of therapeutic options, and barriers to access to essential medicines, a patient living with Chagas disease faces formidable challenges that resemble those faced by someone living with HIV/AIDS," he stated (PLoS One online, May 29, 2012).

But the president of the Chagas Disease Foundation called the comparison "unfortunate," adding that unlike HIV/AIDS, Chagas disease can be effectively treated in a short period of time.