Identification of Rickettsiae from Ticks Collected in the Central African Republic Using the Polymerase Chain Reaction

Dupont, Hervé; Cornet, Jean-Paul; Raoult, Didier

doi:10.4269/ajtmh.1994.50.373

Cited by 71 publications

(41 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…(22). Previous reports of R. rhipicephali in Europe and Africa were based on PCR-restriction fragment length polymorphism profiles compatible with R. rhipicephali after digestion of ompA PCR products obtained from ticks (2,11,16). Thus, further studies based on isolation in cell culture and/or DNA sequencing of PCR products need to be conducted to confirm the presence of R. rhipicephali outside the New World.…”

Section: Discussionmentioning

confidence: 99%

Isolation of Rickettsia rhipicephali and Rickettsia bellii from Haemaphysalis juxtakochi Ticks in the State of São Paulo, Brazil

Labruna

Pacheco

Richtzenhain

et al. 2007

Appl Environ Microbiol

View full text Add to dashboard Cite

In the present study, attempts to isolate Rickettsia in cell culture were performed individually in seven specimens of Haemaphysalis juxtakochi ticks collected in the state of São Paulo (southeastern Brazil). Rickettsia was successfully isolated by the shell vial technique and established in Vero cell culture from six ticks (six isolates). DNA extracted from infected cells of these isolates was tested by PCR and DNA sequencing, using genus-specific Rickettsia primers targeting the genes gltA, htrA, ompA, and ompB. After the generated sequences were compared with available sequences in GenBank, five out of the six isolates were identified as Rickettsia bellii (isolates HJ#1, HJ#2, HJ#3, HJ#4, and HJ#7). The sixth isolate (HJ#5) was closest to Rickettsia sp. strain R300, previously detected in H. juxtakochi in northern Brazil, and to Rickettsia rhipicephali, isolated from ticks in the United States. Following recent gene sequence-based criteria proposed for the identification of Rickettsia isolates, both isolate HJ#5 and strain R300 were identified as South American strains of R. rhipicephali, which was confirmed in this continent for the first time. Isolation of R. bellii from H. juxtakochi ticks, added to eight other tick species that have been reported to be infected with this bacterium in Brazil, indicates that R. bellii is indeed the most frequent Rickettsia species infecting ticks in Brazil. Currently, the role of both R. rhipicephali and R. bellii as human pathogens is regarded as unknown.

show abstract

Section: Discussionmentioning

confidence: 99%

Isolation of Rickettsia rhipicephali and Rickettsia bellii from Haemaphysalis juxtakochi Ticks in the State of São Paulo, Brazil

Labruna

Pacheco

Richtzenhain

et al. 2007

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…When other tick species were found to be infected with rickettsia-like organisms (RLO), they were considered to be "secondary" vectors of R. conorii (21). More recently, however, it has been shown that other SFG rickettsiae occur throughout Africa and that several tick species carry rickettsiae different from R. conorii (7,41).The presence of RLO in Hyalomma ticks of Morocco and Sudan was first reported in the 1950s (21). RLO have been detected by PCR and direct immunofluorescence in H. impeltatum, H. dromedari, and H. anatolicum in Egypt; however, they have not been identified (30).…”

mentioning

confidence: 99%

mentioning

confidence: 99%

Rickettsia aeschlimannii sp. nov., a New Spotted Fever Group Rickettsia Associated with Hyalomma marginatum Ticks

Béati

Meskini

Thiers

et al. 1997

International Journal of Systematic Bacteriology

153

View full text Add to dashboard Cite

We formally propose the name Rickettsia aeschlimannii sp. nov. for a new spotted fever group (SFG) rickettsia, strain MCMT, isolated from Hyalumma marginatum marginatum ticks collected in Morocco. This organism shows a typical rickettsial morphology when analyzed by electron microscopy. After characterization by serotyping, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Western immunoblotting, PCR-restriction fragment length polymorphism (RFLP), pulsed-field gel electrophoresis, and 16s rDNA sequencing, this organism was found to be different from all of the recognized SFG rickettsiae. Identical PCR-FWLP profiles have, however, been found in H. marginatum marginatum from Portugal and H. marginatum rujipes from Zimbabwe, which suggests that the distribution of this rickettsia reaches from the Mediterranean to southern Africa.Although the first descriptions of Mediterranean spotted fever and its ecology were made in northern Africa (13) and one of the reference strains of Rickettsia conorii is called the Moroccan strain, there have been few recent reports about the ecology and epidemiology of rickettsioses in this area (31). In early studies, all three African spotted fever group (SFG) rickettsioses, Mediterranean spotted fever, South African tick bite fever, and Kenyan tick typhus (25), were attributed to infection with R. conorii. The recognized vectors were dog ticks: Rhipicephalus sanguineus in the Mediterranean area (11) and Rhipicephalus simus or Haemaphysalis leachi in the eastern and southern regions of Africa (22,27). When other tick species were found to be infected with rickettsia-like organisms (RLO), they were considered to be "secondary" vectors of R. conorii (21). More recently, however, it has been shown that other SFG rickettsiae occur throughout Africa and that several tick species carry rickettsiae different from R. conorii (7,41).The presence of RLO in Hyalomma ticks of Morocco and Sudan was first reported in the 1950s (21). RLO have been detected by PCR and direct immunofluorescence in H. impeltatum, H. dromedari, and H. anatolicum in Egypt; however, they have not been identified (30). During a large-scale field survey in Zimbabwe, hemolymph tests showed that 11% of Hyalomma marginatum rufipes ticks were infected with RLO (7). Although isolation attempts were unsuccessful, PCR-restriction fragment length polymorphism (RFLP) analysis showed that these ticks contained SFG rickettsiae genotypically similar to a strain (PoTiR8) isolated from H. marginatum marginaturn ticks from Portugal (2). Strain PoTiR8 has, however, not been further characterized.In Morocco, H. marginatum marginaturn is one of the most widely distributed tick species, possibly representing up to 42% of the tick burden of cattle (3, 32). Although in its juvenile stages it usually bites birds, under particular circumstances it may also infest humans (23). We present here the first description of an SFG rickettsial strain (MC16T) isolated from Moroccan H. marginaturn marginaturn. This isolate was compared to the recogn...

show abstract

“…In Cameroon, A. variegatum (Figure 1b) www.intechopen.com has been identified as the potential vector with about 75% of ticks (male and female) collected from cattle found to be infected with R. africae (Ndip et al, 2004b). Reports from other studies have indicated that R. africae infection in Amblyomma ticks frequently has a high prevalence (up to 100%) reported in ticks collected in some disease-endemic countries (Dupont et al, 1994;Parola et al, 2001). Like any other tick borne disease, the ecological characteristics of the vector influence the epidemiology of the disease.…”

Section: Tick Vectors and Reservoirsmentioning

confidence: 98%

“…Another species, R. aeschlimannii, which was first isolated in H. marginatum ticks in Morocco (Beati et al, 1997) and later detected in H. marginatum rufipes in Mali and Niger, have been known to cause infections in tourists returning from Morocco and South Africa (Parola et al, 2001). R. massiliae, first isolated from R. sanguineus ticks in Marseille, France (Parola et al, 2005) was detected in R. muhsame, R. lunalatus and R. sulcatus from Central African Republic (Dupont et al, 1994) and in R. muhsame ticks collected from cattle in Mali 2001) and Ivory Coast (Berrelha et al, 2009). Rickettsia felis is a recently identified pathogen which was first detected in Ctenocephalides felis fleas (Bouyer et al, 2001).…”

Section: The Genus Rickettsiamentioning

confidence: 99%

Human Ehrlichioses and Rickettsioses in Cameroon

Ndip¹,

Ndip²,

Walker³

et al. 2012

Current Topics in Tropical Medicine

View full text Add to dashboard Cite

Identification of Rickettsiae from Ticks Collected in the Central African Republic Using the Polymerase Chain Reaction

Cited by 71 publications

References 23 publications

Isolation of Rickettsia rhipicephali and Rickettsia bellii from Haemaphysalis juxtakochi Ticks in the State of São Paulo, Brazil

Isolation of Rickettsia rhipicephali and Rickettsia bellii from Haemaphysalis juxtakochi Ticks in the State of São Paulo, Brazil

Rickettsia aeschlimannii sp. nov., a New Spotted Fever Group Rickettsia Associated with Hyalomma marginatum Ticks

Human Ehrlichioses and Rickettsioses in Cameroon

Contact Info

Product

Resources

About