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PubMed2006

[Study on the coinfection status of Borrelia burgdorferi sensu lato and spotted fever group Rickettsia in ticks from Hunchun, Jilin province].

OBJECTIVE: To understand the coinfection status of Borrelia burgdorferi sensu lato (B.b.s.l) and spotted fever group Rickettsia (SFGR) in Hunchun of Jilin province, China. METHODS: Polymerase chain reaction (PCR) was used to detect the 5S-23S rRNA intergenic spacer of B. b. s. l and ompA of SFGR in ticks was collected in Hunchun,Jilin province. The amplification products of positive ticks were sequenced, and phylogenetic analysis was conducted by PHYLIP software package. RESULTS: The infection rate of B. b. s. l was 36.0% in Ixodes persulcatus ticks and the SFGR was discovered in I. persulcatus ticks,with an infection rate of 2.0%. The coinfection rate of both agents was 2.0%. In 327 Dermacentor siltarum ticks, the positive rates of B. b. s. l and SFGR were 30.9% and 29.1% respectively. 55 ticks (16.8%) were coinfected with the two pathogens. The sequence analysis of B. b. s. l showed that the B. b. s. l in Jilin area, which were highly homologous, all belonged to B. garinii genotypes. The sequence analysis of SFGR positive products showed that the DNA secquence of the newly detected agent (JL-95) was close to the two previously described rickettsiae which were detected in I. ricinus from Slovakia (called IRS3 and IRS4). Phylogenetic relationships inferred from the comparison of these sequences with those of other genus Rickettsiae indicated that JL-95, IRS3 and IRS4 constituted a new rickettsial genotype and formed a separate cluster among the spotted fever group Rickettsiae. CONCLUSION: Coinfection of B. b. s. l and SFGR existed in Hunchun, Jilin province. The sequencing of specific fragment confirmed a new SFGR which was different from other rickettsiae known in China.

Animals↗
PubMed1989

Imported rickettsial African spotted fever in Japan.

A 45-year-old Japanese man developed a black eschar skin lesion and on the body, a number of erythematous seropapules 2 weeks after his return from South Africa. Within 24 h of treatment with minocycline he was afebrile and symptomatically much improved. Serological tests showed increased antibody titres to spotted fever group rickettsiae (SFGR). From the clinical and serological findings we consider this patient to be the first in Japan to have been infected with SFGR in Africa.

Antibodies, Bacterial↗
PubMed1999

The map1 gene of Cowdria ruminantium is a member of a multigene family containing both conserved and variable genes.

Heartwater is an economically important disease of ruminants caused by the tick-transmitted rickettsia Cowdria ruminantium. The disease is present in Africa and the Caribbean and there is a risk of spread to the Americas, particularly because of a clinically asymptomatic carrier state in infected livestock and imported wild animals. The causative agent is closely related taxonomically to the human and animal pathogens Ehrlichia chaffeensis and Ehrlichia canis. A dominant immune response of infected animals or people is directed against variable outer membrane proteins of these agents known, in E. chaffeensis and E. canis, to be encoded by polymorphic multigene families. We demonstrate, by sequence analysis, that map1 encoding the major outer membrane protein of C. ruminantium is also encoded by a polymorphic multigene family. Two members of the gene family are located in tandem in the genome. The upstream member, orf2, is conserved, encoding only 2 amino acid substitutions among six different rickettsial strains from diverse locations in Africa and the Caribbean. In contrast, the downstream member, map1, contains variable and conserved regions between strains. Interestingly, orf2 is more closely related in sequence to omp1b of E. chaffeensis than to map1 of C. ruminantium. The regions that differ among orf2, map1, and omp1b correspond to previously identified variable sequences in outer membrane protein genes of E. chaffeensis and E. canis. These data suggest that diversity in these outer membrane proteins may arise by recombination among gene family members and offer a potential mechanism for persistence of infection in carrier animals.

Africa↗
PubMed2004

Prevalence of antibodies to spotted fever group rickettsiae in humans and domestic animals in a Brazilian spotted fever-endemic area in the state of São Paulo, Brazil: serologic evidence for infection by Rickettsia rickettsii and another spotted fever group Rickettsia.

In serum samples obtained from all the healthy humans, horses, dogs, and donkeys present on three farms in the Pedreira Municipality, an endemic area for Brazilian spotted fever, an indirect immunofluorescence assay (IFA) detected antibodies against Rickettsia rickettsii in 17 (77.3%) horses, 5 (31.3%) dogs (titers ranging from 64 to 4,048), and none of 4 donkeys or 50 humans. Five canine and eight equine sera with high antibody titers to R. rickettsii were also tested by IFA against R. bellii, R. akari, and R. africae antigens. Sera from two horses and two dogs that showed similar high antibody titers against two rickettsial antigens were evaluated after cross-absorption. Sera from seven horses and two dogs contained antibodies specific for R. rickettsii, and one dog serum had antibodies against a Rickettsia species very closely related to R. africae. The latter may have been caused by infection with the recently identified COOPERI strain.

Animals↗
PubMed2006

Prospective evaluation of rickettsioses in the Trakya (European) region of Turkey and atypic presentations of Rickettsia conorii.

In 2004 between the months of May-November, 11 patients with spotted fever group (SFG) rickettsioses were admitted to the Trakya University Hospital in Edirne, Turkey. SFG rickettsioses were diagnosed clinically. Before treatment, punch biopsy from skin lesions, especially from the eschar, was performed. Serum specimens were tested by IFA using a panel of nine rickettsial antigens, including SFG rickettsiae and R. typhi. Western blotting and standard PCR were also performed. The average age of the 11 patients (4 male and 7 female) was 51 years. All the patients had high fever; 10 (91%) had maculopapular rash; 8 (73%) had rash in the palms or on the soles. Five patients had a unique eschar; two had double eschars (64%). Two patients presented with multiple organ failure and one of them died. All the patients had significant antibody titers against SFG rickettsiae. PCR experiments of skin biopsies were positive in six (60%) of 10 skin biopsy samples and DNA sequencing of the positive PCR products gave 100% homology with Rickettsia conorii Malish 7 for opmA and gltA. Trakya Region in an endemic area for rickettsioses. In this series, three patients presented with life-threatening diseases and one of them died. This patient was the first fatal case (2.8%). Atypic and serous life-threatening presentations of rickettsioses must be kept in mind for the differential diagnosis of febrile disease in Turkey.

Boutonneuse Fever↗
PubMed1996

Genetic variation in Australian spotted fever group rickettsiae.

Rickettsiae were isolated by cell culture of buffy coat blood from six patients with spotted fever from southeastern Australia and Flinders Island in Bass Strait. The isolates were genetically compared with two previous Rickettsia australis patient isolates. The genus-specific 17-kDA genes from the isolates were compared after DNA amplification and restriction fragment analysis of the amplified DNA. This comparison revealed that mainland rickettsial isolates from southeastern Australia were identical to two previous isolates of R. australis from northeastern Australia. Rickettsial isolates from Flinders Island were distinct from the mainland isolates. The 16S rRNA gene sequences from the isolates were determined and compared. The Flinders Island rickettsial agent was most closely related (0.3% structural divergence) to Rickettsia rickettsii, Rickettsia conorii, and Rickettsia slovaca. The Flinders Island rickettsial agent was 1.3 and 2.1% structurally divergent from R. australis and Rickettsia akari, respectively. The 16S rRNA gene sequence from the Flinders Island agent shows that this rickettsia is more closely related to the rickettsial spotted fever group than is R. australis. We conclude that there are two populations of spotted fever group rickettsiae in Australia and propose that the genetically distinct causative organism of Flinders Island spotted fever be designated Rickettsia honei. The extent of distribution and animal host reservoirs remain to be elucidated.

Adult↗
PubMed2003

Outbreak of scrub typhus in southern India during the cooler months.

Orientia tsutsugamushi, the agent of scrub typhus, is a strict intracellular bacterium which is found in many parts of Asia including India. During the past few years, the number of patients with rickettsial infection and scrub typhus has increased, especially during the cooler months. We report in this study a recent outbreak of scrub typhus recorded during the cooler months (October 2001 to February 2002) in patients admitted to our hospital with acute febrile illness associated with diverse signs and symptoms. Overall, 28 patients were clinically and serologically confirmed to have scrub typhus. Fever for more than one week was the only common manifestation. Myalgias was the next most common feature (52%), and rash was observed in only 22% of the cases. Seventeen patients treated with doxycycline recovered in 1 to 3 days, as well as two patients who received chloramphenicol. In five patients who received ciprofloxacin, fever subsided only after five days. Finally three patients (10.7%) died, including one patient treated with doxycycline. These data indicate that scrub typhus is a reemerging infectious disease in India with a possibility of drug resistance. This reemergence emphasizes the need for further prospective studies to design effective control measures.

Adolescent↗
PubMed2005

[Acute encephalopathy among patients with renal dysfunction after ingestion of "sugihiratake", angel's wing mushroom--study on the incipient cases in the northern area of Niigata Prefecture].

An outbreak of acute encephalopathy among 6 patients with renal dysfunction after eating "Sugihiratake" mushroom in the northern area of Niigata Prefecture was reported. All of the patients had varying degrees of renal dysfunction, and 3 of them were on dialysis treatment. Patients initially presented with shaking limbs and difficulty in walking. Several days later, disturbances in consciousness developed, which were followed by status epileptics. Four patients were put on mechanical ventilation for seizure control. Two of the 6 cases died. CSF examination showed elevated protein without pleocytosis; bacterial, rickettsial and viral screenings was negative. Brain CT and MRI studies showed edema in the claustrum and external capsule, and in the white matter of the base of the frontal, parietal, and temporal lobes. No common drug administration was recognized. All of the patients had a history to have ingested "Sugihitarake" mushroom (angels' wing mushroom, pleurocybella porrigens) in varying quantities and frequencies prior to the onset of the illness. This mushroom may have induced toxic encephalopathy although no similar case have been reported in the past.

Acute Disease↗
PubMed1995

Q fever in the Greek Island of Crete: epidemiologic, clinical, and therapeutic data from 98 cases.

A retrospective study was undertaken in Crete, Greece, to investigate the epidemiologic, clinical, and therapeutic aspects of Q fever. Over a period of 5 years (1989-1993), 1,298 patients were examined and 98 cases were identified. Individuals who were aged 20-29 years and 30-39 years appeared to have an increased risk of infection. Contact with animals was found to be a major risk factor for acquisition of Q fever. The predominant clinical manifestations of the infection were fever (91.7% of patients) and respiratory disease (88.5%), whereas hepatitis was the dominant feature in only a minority (7.1%) of patients. Chest radiographs frequently revealed pulmonary interstitial changes (36.4% of patients) and alveolar changes (34.4%). Abnormal echocardiographic findings were also observed. There was no difference in the duration of fever whether the patient received therapy with tetracycline or erythromycin, a finding that may be explained by the delay in initiating tetracycline therapy.

Adult↗
PubMed1993

High-level expression of a 56-kilodalton protein gene (bor56) of Rickettsia tsutsugamushi Boryong and its application to enzyme-linked immunosorbent assays.

The 56-kDa protein of Rickettsia tsutsugamushi, which is located on the rickettsial surface, has been shown to be an immunodominant antigen. The gene that encodes the 56-kDa protein of R. tsutsugamushi Boryong (bor56) was cloned. Sequencing revealed an open reading frame of 1,602 bp encoding 534 amino acids with a molecular weight of 56,803. The 56-kDa protein of R. tsutsugamushi Boryong (Bor56) was expressed as a fusion protein with the maltose-binding protein of Escherichia coli by deleting 252 bp from the 5' end of the open reading frame and subcloning it into the StuI site of pIH821. The recombinant fusion protein was purified by amylose column chromatography for application in an enzyme-linked immunosorbent assay to evaluate the ability of the method to detect the antibody to R. tsutsugamushi in human patient sera. By using sera from 100 patients with scrub typhus and 70 patients with other febrile diseases, a high diagnostic sensitivity (95%) and a high diagnostic specificity (100%) were demonstrated, suggesting the suitability of the recombinant antigen for use as an immunodiagnostic tool.

ATP-Binding Cassette Transporters↗
PubMed1975

Study of rickettsioses in Slovakia. I. Coxiella burneti and Rickettsiae of the spotted fever (SF) group in ticks and serological surveys in animals and humans in certain selected localities in the Lucenec and V. Krtís districts.

A study of the natural focus character of Q fever and the rickettsiosis caused by organisms of the SF group carried out in 1971-1973 in 7 selected villages in the Lucenec district and in a few control villages in the V. Krtis district, produced the following results: Among a total number of 2,200 ticks belonging to the species Dermacentor marginatus, Ixodes ricinus and Haemaphysalis punctata and tested for the presence of rickettsial organisms by the haemocyte test, C. burneti was detected in 8 from the chosen localities--in 2 females and 1 male of D. marginatus in Luborec, in 1 2. ricinus female in Maskova and in 1 female and 3 males of I. ricinus in Pincina--and in 5 from the control localities--in 1 D. marginatus female in Prebelce and in 3 females and 1 male of D. marginatus in V. Lom.

Animals↗
PubMed2005

Immune-mediated haemolytic anaemia and thrombocytopenia associated with Anaplasma phagocytophilum in a dog.

A 10-year-old, crossbreed dog was presented with a history of severe lethargy, pyrexia and inappetence of several days' duration. Clinical examination revealed pallor of the mucous membranes, petechiae, generalised lymphadenopathy and effusions in multiple joints. Laboratory evaluation showed severe anaemia and thrombocytopenia, with positive in-saline agglutination and the presence of antiplatelet antibodies. The DNA of Anaplasma phagocytophilum, an endemic granulocytic rickettsial parasite, was detected by PCR. A poor response to doxycycline and immunosuppressive therapy with corticosteroids was seen. Euthanasia was performed after the development of disseminated intravascular coagulation. Postmortem examination demonstrated changes consistent with the development of disseminated intravascular coagulation and infection with granulocytic ehrlichiosis. This case documents the presence of canine granulocytic ehrlichiosis caused by A phagocytophilum in the U.K., and highlights the range of clinical signs and clinicopathological abnormalities that may be observed in infected dogs.

Anaplasma phagocytophilum↗
PubMed2001

[Hepatic granulomas of infectious origins].

Hepatic granulomas of infectious origin are due to several causes. Bacterial and rickettsial infections are the most frequent (mainly tuberculosis, infections due to atypical mycobacteria, Q fever). However parasitic and fungal infections may also be involved. Histological characteristics of the granuloma are sometimes suggestive of the cause, but the aetiological diagnosis often results from a careful confrontation of clinical, biological, and histological data. One should always have in mind the possibility of tuberculosis, where an effective treatment must be given as early as possible. The cause of granulomas remains unknown in approximately half the cases after careful investigations.

Bacterial Infections↗
PubMed1994

Clinical ehrlichiosis in a cat.

Clinical ehrlichiosis was diagnosed in a cat from Colorado on the basis of cytologic, serologic, and clinical findings. Clusters of gram-negative organisms that were morphologically similar to morulae of Ehrlichia spp were found only in mononuclear cells. The cat had clinical signs that were referable to infection by a rickettsial organism, and antibodies against E canis (titer, 1:80) and E risticii (titer, 1:40) were detected in serum. Exclusion of other obvious causes inducing similar clinical signs, and positive clinical response to doxycycline, an antibiotic with known antirickettsial actions, aided in diagnosis. The cat was clinically normal within days following initiation of treatment, and was clinically normal, as well as seronegative for antibodies against E canis and E risticii, 1,365 days after discharge.

Animals↗
PubMed1995

Effectiveness of a dot-blot immunoassay of anti-Rickettsia tsutsugamushi antibodies for serologic analysis of scrub typhus.

We compared a commercially available dot-blot immunoassay system with the indirect immunofluorescence assay (IFA) in tests of known negative and known positive sera from scrub typhus cases. Using a panel of 100 sera from patients with various rickettsial and nonrickettsial infections, we observed that the IFA was 99% specific and the dipstick assay was 98% specific. In tests of 91 sera (30 negative and 61 positive for scrub typhus antibodies) from a study of febrile patients in Malaysia, using the standard of an IFA titer < 1:64 as negative, an IFA titer > 1:128 as positive, and an IFA titer = 1:64 as either positive or negative (supported by clinical records), dipsticks were 83% specific and 90% sensitive. The quantitative correlation of the dipsticks to IFA titers was confirmed by significant differences in geometric means of inverse IFA titers corresponding to the number of positive dipstick spots (no dots = 8.5, one dot = 43.3, two dots = 206.7, and three dots = 676.9). The assay would enable physicians and public health workers who deal with patients to quickly diagnose and appropriately treat most cases of the disease, especially in areas of high prevalence where the proportion of false-positive results to true-positive results would be low.

Antibodies, Bacterial↗
PubMed2004

Possible death of a buffalo calf (Syncercus caffer) due to suspected heartwater (Ehrlichia ruminantium).

Rickettsial organisms resembling Ehrlichia ruminantium (the causative organism of heartwater) were demonstrated in brain smears and formalin-fixed brain sections derived from a buffalo calf that died on a private game reserve in northern KwaZulu-Natal. The possibility that the tick-free environment of a quarantine boma may have affected the calf's immunity, is discussed. These findings suggest that monitoring heartwater in wild ruminants and making brain smears as a routine during post mortem evaluations of wild ruminants, should be encouraged.

Animals↗
PubMed1991

Ehrlichiosis.

Ehrlichiae are tick-borne rickettsial organisms that are well known as veterinary pathogens. However, since 1986, over 100 cases of human infection by Ehrlichia canis or a closely related species have been identified primarily in the southeastern and south central United States. Human ehrlichiosis is characterized by high fever, rigors, headache, myalgia, anorexia, and, sometimes, gastrointestinal complaints. Rash occurs in a minority of cases. Commonly observed laboratory abnormalities include leukopenia, thrombocytopenia, anemia, and elevated hepatic aminotransferase levels. The illness is tick-borne and tetracycline or tetracycline analogs appear to be effective in treating the illness.

Animals↗
PubMed2000

Ectoparasites and gastrointestinal helminths of southern flying squirrels in southeast Georgia.

Southern flying squirrels (Glaucomys volans) from southeastern Georgia were examined for ectoparasites and gastrointestinal helminths. Ten species of ectoparasites were recovered, including 3 species of sucking lice (Hoplopleura trispinosa, Microphthirus uncinatus, and Neohaematopinus sciuropteri), 1 species of flea (Orchopeas howardi), 2 species of ticks (Amblyomma maculatum and Ixodes scapularis), 3 species of mesostigmatid mites (Androlaelaps casalis, A. fahrenholzi, and Haemogamasus ambulans), and 1 species of chigger (Leptotrombidium peromysci). Only the sucking lice and fleas were common on this host. M. uncinatus is reported for the first time from eastern North America. The 2 most commonly collected ectoparasites, N. sciuropteri (prevalence = 63%) and O. howardi (prevalence = 47%), have previously been shown to be vectors of the rickettsial zoonotic agent that causes sporadic epidemic typhus. Also, 3 nematodes (Citellinema bifurcatum, Strongyloides robusius, and Syphacia thompsoni), 1 unidentified cestode, and 1 acanthocephalan (Moniliformis clarki) were found in flying squirrel gastrointestinal tracts. With the exception of S. thompsoni, which was common and relatively abundant in the cecum (prevalence = 94%, intensity = 51+/-12), both the prevalence and intensity of helminth parasites were low. The nematode S. thompsoni and the acanthocephalan M. clarki are new state records for tree squirrels in Georgia.

Animals↗