Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 Jan;94(1):26-34.
doi: 10.4269/ajtmh.15-0472. Epub 2015 Aug 31.

National Surveillance of Spotted Fever Group Rickettsioses in the United States, 2008-2012

Naomi A Drexler  1 , F Scott Dahlgren  2 , Kristen Nichols Heitman  2 , Robert F Massung  2 , Christopher D Paddock  2 , Casey Barton Behravesh  2
Affiliations

National Surveillance of Spotted Fever Group Rickettsioses in the United States, 2008-2012

Naomi A Drexler et al. Am J Trop Med Hyg. 2016 Jan.

Abstract

Spotted fever group (SFG) rickettsioses are notifiable conditions in the United States caused by the highly pathogenic Rickettsia rickettsii and less pathogenic rickettsial species such as Rickettsia parkeri and Rickettsia sp. 364D. Surveillance data from 2008 to 2012 for SFG rickettsioses are summarized. Incidence increased from 1.7 cases per million person-years (PY) in 2000 to 14.3 cases per million PY in 2012. During 2008-2012, cases of SFG rickettsiosis were more frequently reported among males, persons of white race, and non-Hispanic ethnicity. Overall, case fatality rate (CFR) was low (0.4%), however, risk of death was significantly higher for American Indian/Alaska Natives (relative risk [RR] = 5.4) and Asian/Pacific Islanders (RR = 5.7) compared with persons of white race. Children aged < 10 years continue to experience the highest CFR (1.6%). Higher incidence of SFG rickettsioses and decreased CFR likely result from increased reporting of tick-borne disease including those caused by less pathogenic species. Recently, fewer cases have been confirmed using species-specific laboratory methods (such as cell culture and DNA detection using polymerase chain reaction [PCR] assays), causing a clouded epidemiological picture. Use of PCR and improved documentation of clinical signs, such as eschars, will better differentiate risk factors, incidence, and clinical outcomes of specific rickettsioses in the future.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Probable and confirmed cases of spotted fever group (SFG) rickettsiosis 2008–2012, United States (Nationally Notifiable Diseases Surveillance System [NNDSS]).
Figure 2.
Figure 2.
Incidence of spotted fever group (SFG) rickettsiosis by county, United States 2008–2012 (Nationally Notifiable Diseases Surveillance System [NNDSS]).
Figure 3.
Figure 3.
Month of onset of spotted fever group (SFG) rickettsiosis cases in the United States and by region, 2008–2012 (case report forms [CRFs]).
Figure 4.
Figure 4.
Incidence per million person-years (PY) and case fatality rate (CFR) of spotted fever group (SFG) rickettsiosis by 10-year age group, United States 2008–2012 (incidence from Nationally Notifiable Diseases Surveillance System [NNDSS], CFR from case report forms [CRFs]).
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Parola P, Paddock CD, Raoult D. Tick-borne rickettsioses around the world: emerging diseases challenging old concepts. Clin Microbiol Rev. 2005;18:719–756. - PMC - PubMed
    1. Openshaw JJ, Swerdlow DL, Krebs JW, Holman RC, Mandel E, Harvey A, Haberling D, Massung RF, McQuiston JH. Rocky Mountain spotted fever in the United States, 2000–2007: interpreting contemporary increases in incidence. Am J Trop Med Hyg. 2010;83:174–182. - PMC - PubMed
    1. Smadel JE. Status of the rickettsioses in the United States. Ann Intern Med. 1959;51:421–435. - PubMed
    1. Childs JE, Paddock CD. Passive surveillance as an instrument to identify risk factors for fatal Rocky Mountain spotted fever: is there more to learn? Am J Trop Med Hyg. 2002;66:450–457. - PubMed
    1. Holman RC, Paddock CD, Curns AT, Krebs JW, McQuiston JH, Childs JE. Analysis of risk factors for fatal Rocky Mountain spotted fever: evidence for superiority of tetracyclines for therapy. J Infect Dis. 2001;184:1437–1444. - PubMed

Publication types

LinkOut - more resources