| Clinical
Features |
Noninvasive disease (strep throat,
cellulitis, impetigo); invasive disease (necrotizing fasciitis
[NF], streptococcal toxic shock syndrome [STSS], bacteremia,
pneumonia); nonsuppurative sequelae (rheumatic fever, post-streptococcal
glomerulonephritis). STSS is a severe illness characterized
by shock, multiorgan failure. NF presents with severe local
pain, destruction of tissue. Rheumatic fever is a leading
cause of acquired heart disease in young people worldwide. |
| Etiologic
Agent |
Streptococcus pyogenes or
group A streptococcus. |
| Incidence |
Approximately 9,000 cases of invasive
disease (3.2/100,000 population) occurred in 2002; STSS and
NF each accounted for approximately 6% of cases. Over 10 million
noninvasive GAS infections (primarily throat and skin infections)
occur annually. |
| Sequelae |
Death in 10%-13% of all invasive
cases, 45% of STSS, 25% of NF cases. Organ system failure
(STSS) and amputation (NF) also may result. |
| Transmission |
Person to person by contact with
infectious secretions. Asymptomatic pharyngeal carriage occurs
among all age groups but is most common among children. |
| Risk
Groups |
Invasive disease: elderly, immunosuppressed,
persons with chronic cardiac or respiratory disease, diabetes,
skin lesions (i.e. children with varicella [chicken pox],
intravenous drug users) African-Americans, American Indians.
Noninvasive disease: children (especially elementary school
age) at highest risk. |
| Surveillance |
National passive surveillance for
invasive infection and STSS since 1995. Active, population-based
surveillance is conducted in 10 states in the Emerging Infection
Program (total population: 31.5 million). |
| Trends |
Worldwide, rates of invasive disease,
STSS and NF increased from the mid-1980s to early 1990s. Rates
of invasive disease have been stable over the last 5 years
in the United States. Increases in the rate and severity of
disease associated with increases in prevalence of M-1 and
M-3 serotypes (emm types 1 and 3). Resistance to erythromycin
has increased worldwide. |
| Challenges |
Improve recognition and diagnosis
by clinicians; evaluate disease burden and organism characteristics
to guide vaccine development; develop control strategies to
prevent spread in families, institutions, and other high-risk
settings, including the growing population of elderly in long-term
care facilities. |
| Opportunities |
Improved surveillance permits monitoring
disease trends and risk groups. CDC development of new genotyping
system for GAS isolates (emm typing) allows better
strain identification. Investigating clusters will help identify
interventions to prevent the spread of infection. |
|
December 2003
|
