| Clinical
Features |
In neonates: sepsis, pneumonia
and meningitis. Infection in the first week of life is called
"early-onset disease." In adults: sepsis and soft
tissue infections. Pregnancy-related infections: sepsis, amnionitis,
urinary tract infection, and stillbirth. |
| Etiologic
Agent |
Streptococcus agalactiae
or group B streptococcus (GBS). |
| Incidence |
Approximately 19,000 cases occur
annually in the United States; approximately 7,500 occurred
in newborns before recent prevention. The rate of early-onset
infection has decreased from 1.7 cases per 1,000 live births
(1993) to 0.4 cases per 1,000 live births (2002). |
| Sequelae |
Neurologic sequelae include sight
or hearing loss and mental retardation. Death occurs in 5%
of infants and 16% of adults. |
| Costs |
Direct medical costs of neonatal
disease before prevention were $294 million annually. |
| Transmission |
Asymptomatic carriage in gastrointestinal
and genital tracts is common. Intrapartum transmission via
ascending spread from vaginal and/or gastrointestinal GBS
colonization occurs. Mode of transmission of disease in nonpregnant
adults and older infants (>1 week) is unknown. |
| Risk
Groups |
Adults with chronic illnesses (e.g.,
diabetes mellitus and liver failure), pregnant women, the
fetus, and the newborn are at risk. For neonatal disease,
risk is higher among infants born to women with GBS colonization,
prolonged rupture of membranes or preterm delivery. Rates
are substantially higher among blacks and the elderly. |
| Surveillance |
Active surveillance for invasive
GBS disease is ongoing in a multistate population of approximately
30 million, including over 425,000 live births annually. The
disease is not reportable in most states. |
| Trends |
This pathogen emerged in the 1970s
as the most common cause of sepsis in newborns. Adult disease
was recognized more recently. Newborn disease has declined
by 70% since increased use of intrapartum prophylaxis has
occurred. |
| Challenges |
To integrate GBS prevention into
routine obstetric care, by promoting use of CDC guidelines
for GBS prevention, and to evaluate control strategies including
use of intrapartum antibiotics for high-risk women. To assess
whether a portion of preterm or low birthweight deliveries
is due to GBS and is preventable. To characterize risk factors
for newborn disease that develops after the first week of
life. |
| Opportunities |
Interface with community groups
on education and prevention issues, evaluate impact of new
(2002) prevention guidelines on disease occurrence, apply
conjugate vaccine technology to GBS capsular polysaccharide.
Assist other countries that are developing prevention strategies. |
|
December 2003
|
