The number of infants born with syphilis is declining in the United States due largely to improved screening of women in minority communities and Southern states, federal officials said on Thursday.

Women who give birth while infected with the sexually transmitted disease have a higher number of stillbirths and a greater chance of delivering babies that are deaf or prone to bone deformities, seizures and neurological disorders.

The Centers for Disease Control and Prevention, which launched a national syphilis-elimination program in 1998, said there were 451 reported cases of congenital syphilis in 2002 compared to 498 in the previous year and 578 in 2000.

The Atlanta-based agency noted that most of the infants born with the infection in 2002 had mothers who either were never treated or inadequately treated for the disease before or during their pregnancies.

“The majority of congenital syphilis cases in 2002 were preventable,” the CDC said. It said its report highlighted a need to enhance syphilis screening and awareness in high-risk communities and improve doctors’ focus on the disease.

Up to 40 percent of infants born with syphilis die. The disease is easily treated with antibiotics if caught in its early stages, but tissue damage in the final stage is irreversible.

Eradication campaigns have fueled steady declines in syphilis among women aged 15 to 44 since 1991. The rate in this group fell 35 percent between 2000 and 2002.

Efforts to combat infant syphilis, especially in minority groups, are bearing fruit. Prevalence of the disease plummeted about 51 percent among Native Americans and Alaska Natives during the 2000-2002 period.

The same rate fell 22 percent in Hispanics, 21 percent in Asians and 20 percent in blacks but was unchanged for whites. Black and Hispanic babies, however, remained far more likely to be born with syphilis than whites.

Southern states, which tend to have higher rates of many sexually transmitted diseases, led the nation with a nearly 30 percent drop in prevalence of infant syphilis during the three-year period.

Rates also fell in the Western and Midwestern parts of the country, but edged up in the Northeastern United States.