Prospective Study on Symptomatic versus Asymptomatic Infections and Serological Response to Spotted Fever Group Rickettsiae in Two Rural Sites in the Negev (Southern Israel)a

Sarov, Batia; Galil, Aharon; Sikuler, Emanuel; Yagupsky, Pablo; Saah, A. J.; Gilad, Ayelet; Naggan, Lechaim; Sarov, Israel

doi:10.1111/j.1749-6632.1990.tb42226.x

Cited by 14 publications

(6 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Even the nymphs and larvae are infected and a bite from a tick in either of these stages could easily go unnoticed; this might explain why the rate of seroconversion was higher than the rate of reported tick bites. Seroconversion in the absence of a definite clinical syndrome has also been demonstrated in a similar prospective study from Israel (25) and among military personnel in a heavily tick-infested area of Arkansas where seroconversion to SFG rickettsiae occurred in 2.5% (30/1194), 73% of whom did not report any symptoms (26). A high seroprevalence reflects exposure that often leads to asymptomatic infection, possibly due to organisms of low virulence (27).…”

Section: Discussionmentioning

confidence: 70%

Evidence of Rickettsia spp. infection in Sweden: a clinical, ultrastructural and serological study

Nilsson

Lukinius

Påhlson

et al. 2005

APMIS

View full text Add to dashboard Cite

Sweden is an area potentially endemic for spotted fever rickettsioses. Rickettsia helvetica has been isolated from its tick vector Ixodes ricinus, and in a handful of cases linked to human disease. This study demonstrates for the first time in Sweden the transmission of rickettsial infection after a tick bite and the attack rate in an endemic area. We present three cases of documented rickettsial infection and a prospective serological study of Swedish recruits who were trained in the area where the patients lived and showed seroconversion to spotted fever rickettsiae. All patients showed a four-fold increase in antibody titer to the spotted fever rickettsia, R. helvetica, and immunohistochemical examination revealed rickettsia-like organisms in the walls of skin capillaries and veins. Electron microscopy showed organisms resembling R. helvetica and immunogold labeling with two anti-rickettsial antibodies demonstrated specific labeling of the rickettsial organisms in the skin biopsy specimens. Eight of the thirty-five recruits showed a four-fold increase in IgG titer reflecting a high rate of exposure. The results of this study demonstrate that spotted fever rickettsioses should be taken into consideration in the diagnosis of tick-transmitted infections in Sweden.

show abstract

Section: Discussionmentioning

confidence: 70%

Evidence of Rickettsia spp. infection in Sweden: a clinical, ultrastructural and serological study

Nilsson

Lukinius

Påhlson

et al. 2005

APMIS

View full text Add to dashboard Cite

show abstract

“…Previous retrospective serologic surveys detected antibodies to rickettsiae in Zimbabwe, Ivory Coast, Central African Republic, and Egypt ( 15 , 24 – 27 ). However, detecting IgM antibodies to rickettsiae by IFA, in association with febrile illness, is a better approach to identifying recent or current infections; Western immunoblot assay can be used to confirm positive IFA results.…”

Section: Discussionmentioning

confidence: 99%

“…Most previous serologic surveys have detected antibodies in healthy study participants ( 14 , 17 – 19 , 27 ); however, our study population was composed of patients with acute febrile illnesses other than malaria or typhoid fever. The specific cause of the agent that stimulated the antibodies to spotted fever group rickettsiae in these patients remains to be determined.…”

Section: Discussionmentioning

confidence: 99%

Acute Spotted Fever Rickettsiosis among Febrile Patients, Cameroon

Ndip

Bouyer

Rosa

et al. 2004

Emerg. Infect. Dis.

View full text Add to dashboard Cite

Although potential arthropod vectors are abundant in Cameroon, acute febrile illnesses are rarely evaluated for arboviral or rickettsial infections. Serum samples from 234 acutely febrile patients at clinics in Tiko and Buea, Cameroon, were examined for antibodies to Rickettsia africae and African alphaviruses and flaviviruses. These serum samples did not contain antibodies against typhoid, and blood malarial parasites were not detected. Serum samples of 32% contained immunoglobulin M antibodies reactive with R. africae by immunofluorescence assay and were reactive with outer membrane proteins A and B of R. africae by immunoblotting. These findings established a diagnosis of acute rickettsiosis, most likely African tick-bite fever. Hemagglutination inhibition testing of the serum samples also detected antibodies to Chikungunya virus (47%) and flaviviruses (47%). High prevalence of antibodies to arboviruses may represent a major, previously unrecognized public health problem in an area where endemic malaria and typhoid fever have been the principal diagnostic considerations.

show abstract

“…Fatal cases have also been reported (291). Asymptomatic infections have been described and authenticated by seroconversion (230). However, the test used was not specific enough to ensure that the Israeli isolate was definitely the agent provoking seroconversion.…”

Section: Previously Described Diseasesmentioning

confidence: 99%

Rickettsioses as paradigms of new or emerging infectious diseases

1997

View full text Add to dashboard Cite

Rickettsioses are caused by species of Rickettsia, a genus comprising organisms characterized by their strictly intracellular location and their association with arthropods. Rickettsia species are difficult to cultivate in vitro and exhibit strong serological cross-reactions with each other. These technical difficulties long prohibited a detailed study of the rickettsiae, and it is only following the recent introduction of novel laboratory methods that progress in this field has been possible. In this review, we discuss the impact that these practical innovations have had on the study of rickettsiae. Prior to 1986, only eight rickettsioses were clinically recognized; however, in the last 10 years, an additional six have been discovered. We describe the different steps that resulted in the description of each new rickettsiosis and discuss the influence of factors as diverse as physicians' curiosity and the adoption of molecular biology-based identification in helping to recognize these new infections. We also assess the pathogenic potential of rickettsial strains that to date have been associated only with arthropods, and we discuss diseases of unknown etiology that may be rickettsioses.

show abstract

Prospective Study on Symptomatic versus Asymptomatic Infections and Serological Response to Spotted Fever Group Rickettsiae in Two Rural Sites in the Negev (Southern Israel)a

Cited by 14 publications

References 3 publications

Evidence of Rickettsia spp. infection in Sweden: a clinical, ultrastructural and serological study

Evidence of Rickettsia spp. infection in Sweden: a clinical, ultrastructural and serological study

Acute Spotted Fever Rickettsiosis among Febrile Patients, Cameroon

Rickettsioses as paradigms of new or emerging infectious diseases

Contact Info

Product

Resources

About