The aim of this study was to develop quantitative real-time (q)PCR assays to detect all known haemoplasma species, and a human housekeeping gene in order to demonstrate both successful DNA extraction from clinical samples and to test for sample inhibition, and to apply these qPCRs to human blood samples and blood smears. Sensitive and specific generic haemoplasma qPCR assays were developed to amplify haemoplasma species, as well as human glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an internal amplification control. An optimized technique for extracting DNA from stained blood smears was also developed.
View Article and Find Full Text PDFMorphological, cultural, and immuno-histochemical characteristics of "Nanobacterium sanguineum" (NB) described in the literature are reviewed. NB is reported to be a motile, Gram negative organism that divides by binary fission within a calcium-coated slimy shell; this yeast-like shell replicates by budding. It measures between 20 and 200 nm with a unique structure containing 16S ribosomal RNA.
View Article and Find Full Text PDFAfrican tick bite fever, caused by Rickettsia africae, is an emerging zoonotic infection in rural sub-Saharan Africa and the French West Indies. We tested the repellent efficacy of four commercial diethyl-3-methylbenzamide (DEET) lotions against Amblyomma hebraeum Koch, the principal vector of R. africae in southern Africa, by using a human bioassay in which repellent-treated fingers were presented to questing tick nymphs hourly for 4h.
View Article and Find Full Text PDFUntil very recently, Mediterranean spotted fever caused by Rickettsia conorii was the only spotted fever group (SFG) rickettsioses recognized in southern Africa. However, increasing medical awareness of tick-borne infections, together with the introduction of improved isolation methods and the availability of molecular techniques, have led to the identification of several new SFG rickettsioses in the region. African tick bite fever, caused by Rickettsia africae, is currently the most important of these new rickettsioses, affecting large numbers of international travellers each year, but infections due to Rickettsia aeschlimannii and Rickettsia mongolotimonae have also been recently encountered.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
November 2004
The prevalence and diversity of bartonellae infecting the blood of 10 small mammal species inhabiting nine Nature Reserves of the Free State province, South Africa, was assessed using phenotypic, genotypic and phylogenetic methods. Of 86 small mammals sampled, 38 animals belonging to five different species yielded putative bartonellae. Thirty-two isolates were confirmed as bartonellae and were characterized by comparison of partial citrate synthase gene (gltA) sequences.
View Article and Find Full Text PDFWe report the first laboratory-confirmed case of Rickettsia mongolotimonae infection in Africa. The patient sought treatment for an eschar on his toe; lymphangitis, severe headaches, and fever subsequently developed. After a regimen of doxycycline, symptoms rapidly resolved.
View Article and Find Full Text PDFObjective: The purpose of this preliminary study is to evaluate the effect of various wavelengths of light on nanobacteria (NB).
Background Data: NB and mitochondria use light for biological processes. NB have been described as multifunctional primordial nanovesicles with the potential to utilize solar energy for replication.
The bont tick, Amblyomma hebraeum Koch, is the principal vector of Rickettsia africae, the agent of African tick bite fever, in southern Africa. In contrast to most other hard ticks, members of the genus Amblyomma exhibit a characteristic attack host-seeking behavior. The efficacy of topically applied 20% lotions of DEET (diethyl-3-methylbenzamide), the currently considered reference repellent substance, and KBR 3023, a recently developed piperidine compound, was evaluated against laboratory-reared A.
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