Antibodies Reactive to Rickettsia rickettsii Among Children Living in the Southeast and South Central Regions of the United States

Abstract

To our knowledge, this is the largest serosurvey of rickettsial infection in children in the United States. Within the limitations of the immunofluorescence antibody assay, these data suggest that infections with R rickettsii or antigenically related spotted-fever group rickettsiae may be common and subclinical. The results also have implications for the interpretation of single immunofluorescence antibody assay titers in children with suspected Rocky Mountain spotted fever.

Serologic Evidence for Exposure to Rickettsia rickettsii in Eastern Arizona and Recent Emergence of Rocky Mountain Spotted Fever in This Region

“…We found evidence of exposure to R. rickettsii in both children and dogs from Community 1 and Community 2, suggesting that the pathogen was widely distributed throughout the region. Prevalence of antibodies to R. rickettsii in both humans and dogs from the region was as high as that seen in areas of the United States where RMSF is endemic (Carpenter et al 1999, Breitschwerdt et al 1987Hoskins et al 1988, Kelly et al 1982, Marshall et al 2003, Wilfert et al 1985. The pediatric serosurveys in the two communities were conducted in different years and seasons and our results may have been influenced by seasonal differences in tick activity.…”

Serologic Evidence for Exposure to Rickettsia rickettsii in Eastern Arizona and Recent Emergence of Rocky Mountain Spotted Fever in This Region

“…We found evidence of exposure to R. rickettsii in both children and dogs from Community 1 and Community 2, suggesting that the pathogen was widely distributed throughout the region. Prevalence of antibodies to R. rickettsii in both humans and dogs from the region was as high as that seen in areas of the United States where RMSF is endemic (Carpenter et al 1999, Breitschwerdt et al 1987Hoskins et al 1988, Kelly et al 1982, Marshall et al 2003, Wilfert et al 1985. The pediatric serosurveys in the two communities were conducted in different years and seasons and our results may have been influenced by seasonal differences in tick activity.…”

Zoonotic Infections Among Employees from Great Smoky Mountains and Rocky Mountain National Parks, 2008–2009

“…We found evidence of high rates of prior zoonotic infections among NPS employees, in many cases exceeding expected seroprevalence rates for the general population. The seroprevalence of California serogroup viruses (31%), B. henselae (25%), spotted fever group rickettsiae (21%), and flaviviruses (5%), were greater than what is reported in the literature (Yevich et al 1995; Reisen and Chiles 1997; Spach and Koehler 1998; Hilton et al 1999; McCall et al 2001; Marshall et al 2003; Stramer et al 2005). California serogroup bunyavirus infections detected in ROMO predominantly showed specific serological reactivity to Jamestown Canyon virus, consistent with the regional distribution of snow pool mosquito vectors, whereas those detected in GRSM were predominantly seroreactive to La Crosse virus, consistent with the distribution of Aedes triseriatus vectors (Campbell et al 1992).…”

Tick-Borne Rickettsioses around the World: Emerging Diseases Challenging Old Concepts

“…Another recent study identified IgG titers of Ն64 to R. rickettsii in the sera of 239 (12%) 1999 children 1 to 17 years of age, collected from various medical facilities in six southeastern and south-central states in the United States. These investigators suggested that at least some of the seroreactivity identified in this study could be directed against other spotted fever group rickettsiae not previously considered pathogenic and that most infections with SFG rickettsia may be relatively mild (192).…”

Serologic Evidence for Exposure to Rickettsia rickettsii in Eastern Arizona and Recent Emergence of Rocky Mountain Spotted Fever in This Region

“…We found evidence of exposure to R. rickettsii in both children and dogs from Community 1 and Community 2, suggesting that the pathogen was widely distributed throughout the region. Prevalence of antibodies to R. rickettsii in both humans and dogs from the region was as high as that seen in areas of the United States where RMSF is endemic (Carpenter et al 1999, Breitschwerdt et al 1987Hoskins et al 1988, Kelly et al 1982, Marshall et al 2003, Wilfert et al 1985. The pediatric serosurveys in the two communities were conducted in different years and seasons and our results may have been influenced by seasonal differences in tick activity.…”

Zoonotic Infections Among Employees from Great Smoky Mountains and Rocky Mountain National Parks, 2008–2009

“…We found evidence of high rates of prior zoonotic infections among NPS employees, in many cases exceeding expected seroprevalence rates for the general population. The seroprevalence of California serogroup viruses (31%), B. henselae (25%), spotted fever group rickettsiae (21%), and flaviviruses (5%), were greater than what is reported in the literature (Yevich et al 1995; Reisen and Chiles 1997; Spach and Koehler 1998; Hilton et al 1999; McCall et al 2001; Marshall et al 2003; Stramer et al 2005). California serogroup bunyavirus infections detected in ROMO predominantly showed specific serological reactivity to Jamestown Canyon virus, consistent with the regional distribution of snow pool mosquito vectors, whereas those detected in GRSM were predominantly seroreactive to La Crosse virus, consistent with the distribution of Aedes triseriatus vectors (Campbell et al 1992).…”

Tick-Borne Rickettsioses around the World: Emerging Diseases Challenging Old Concepts

“…Another recent study identified IgG titers of Ն64 to R. rickettsii in the sera of 239 (12%) 1999 children 1 to 17 years of age, collected from various medical facilities in six southeastern and south-central states in the United States. These investigators suggested that at least some of the seroreactivity identified in this study could be directed against other spotted fever group rickettsiae not previously considered pathogenic and that most infections with SFG rickettsia may be relatively mild (192).…”

Serologic Evidence for Exposure to Rickettsia rickettsii in Eastern Arizona and Recent Emergence of Rocky Mountain Spotted Fever in This Region

“…We found evidence of exposure to R. rickettsii in both children and dogs from Community 1 and Community 2, suggesting that the pathogen was widely distributed throughout the region. Prevalence of antibodies to R. rickettsii in both humans and dogs from the region was as high as that seen in areas of the United States where RMSF is endemic (Carpenter et al 1999, Breitschwerdt et al 1987Hoskins et al 1988, Kelly et al 1982, Marshall et al 2003, Wilfert et al 1985. The pediatric serosurveys in the two communities were conducted in different years and seasons and our results may have been influenced by seasonal differences in tick activity.…”

Zoonotic Infections Among Employees from Great Smoky Mountains and Rocky Mountain National Parks, 2008–2009

“…We found evidence of high rates of prior zoonotic infections among NPS employees, in many cases exceeding expected seroprevalence rates for the general population. The seroprevalence of California serogroup viruses (31%), B. henselae (25%), spotted fever group rickettsiae (21%), and flaviviruses (5%), were greater than what is reported in the literature (Yevich et al 1995; Reisen and Chiles 1997; Spach and Koehler 1998; Hilton et al 1999; McCall et al 2001; Marshall et al 2003; Stramer et al 2005). California serogroup bunyavirus infections detected in ROMO predominantly showed specific serological reactivity to Jamestown Canyon virus, consistent with the regional distribution of snow pool mosquito vectors, whereas those detected in GRSM were predominantly seroreactive to La Crosse virus, consistent with the distribution of Aedes triseriatus vectors (Campbell et al 1992).…”

Tick-Borne Rickettsioses around the World: Emerging Diseases Challenging Old Concepts

“…Another recent study identified IgG titers of Ն64 to R. rickettsii in the sera of 239 (12%) 1999 children 1 to 17 years of age, collected from various medical facilities in six southeastern and south-central states in the United States. These investigators suggested that at least some of the seroreactivity identified in this study could be directed against other spotted fever group rickettsiae not previously considered pathogenic and that most infections with SFG rickettsia may be relatively mild (192).…”