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S Vene

Publications and source records attributed to S Vene.

At least 19 recordsLinked to original sources
PubMed2004

Concomitant or consecutive infection with Coxiella burnetii and tickborne diseases.

BACKGROUND: Q fever is a worldwide zoonosis caused by Coxiella burnetii, which can be isolated from ticks. Reports of people with both Q fever and other tickborne diseases are rare. In this study, we describe 6 patients with Q fever who were infected with 1 of the following tickborne pathogens: Rickettsia conorii (2 patients), Rickettsia slovaca (2), Rickettsia africae (1), and Francisella tularensis (1). METHODS: Diagnoses were made on the basis of results of microimmunofluorescence assays for detection of C. burnetii, R. conorii, R. slovaca, R. africae, and F. tularensis antigens. Cross-adsorption studies and Western blots were used to confirm dual infections. RESULTS: Among the 6 cases presented, 3 were probably due to a concomitant infection after a tick bite, whereas the remaining 3 were more likely consecutive infections. CONCLUSIONS: Because acute Q fever is often asymptomatic, we recommend that patients infected with the tickborne pathogens mentioned above also undergo routine testing for concurrent infections with C. burnetii.

Adult↗
PubMed2004

No serological evidence of Rickettsia helvetica infection in Scandinavian sarcoidosis patients.

Many agents have been suggested to elicit sarcoidosis, and, recently, an association was presented between this disease and the bacterium Rickettsia helvetica. The aim of this study was to investigate if serological support for such an association could be detected. Sera from 20 well-characterised sarcoidosis patients were investigated for anti-rickettsial immunoglobulin G antibodies with a micro-immunofluorescence technique. R. helvetica, R. conorii and R. typhi served as antigens. In conclusion, none of the investigated sera displayed detectable titres of anti-rickettsial immunoglobulin G antibodies. Thus, the current study does not support an association between rickettsia and sarcoidosis.

Adult↗
PubMed2003

Sequential changes in hematologic and biochemical parameters in African tick bite fever.

OBJECTIVE: To evaluate the sequential changes and to estimate the frequencies of abnormalities in some commonly measured biological variables in patients with African tick bite fever (ATBF), an emerging spotted fever group (SFG) rickettsiosis in international travelers to rural sub-Saharan Africa. METHODS: A study was done of hemoglobin, total leukocyte count, absolute lymphocyte count, blood platelet count and serum levels of C-reactive protein (S-CRP), alanine aminotransferase (S-ALAT), aspartate aminotransferase, lactic dehydrogenase, gamma-glutamyl transferase, alkaline phosphatase, bilirubin, sodium and creatinine during the first two weeks of illness and prior to the institution of antirickettsial therapy in 108 patients with travel-associated ATBF. RESULTS: There were significant falls in mean total leukocyte count, mean absolute lymphocyte count, and mean platelet count, and significant increases in mean S-CRP and S-ALAT. During the first ten days of illness, elevated S-CRP, lymphopenia and elevated S-ALAT were detected in 91.7%, 73.3% and 40.7% of patients, respectively. Most abnormalities were mild. For 55 patients who underwent both S-CRP and absolute lymphocyte count determination, at least one parameter was abnormal in 52 (94.5%) patients. CONCLUSIONS: The sequential changes in many biological parameters during the acute phase of ATBF mimic those reported in other SFG rickettsioses. Mild abnormalities are frequent, with increased S-CRP and lymphopenia being the two most consistent findings.

Adolescent↗
PubMed2002

Hantavirus infections in Latvia.

In order to investigate the presence of hantavirus infections in Latvia, 333 randomly selected human serum samples were screened using an enzyme-linked immunoassay. Fifteen samples were positive for hantavirus-specific IgG and were subsequently serotyped using a focus reduction neutralization test. Fourteen of these samples neutralized at least one of the hantaviruses included in the test, indicating a 4.2% overall seroprevalence in Latvia. Among 14 focus reduction neutralization test-positive sera, specific reactivity (at least 4-fold higher endpoint titer) of neutralizing antibodies was as follows: six sera were specific for Saaremaa hantavirus, three showed equal titers to Saaremaa and Dobrava hantaviruses, and five showed the highest endpoint titers to Puumala hantavirus. Hantavirus infections were confirmed in individuals residing in 11 of 26 investigated counties. The sex ratio was 1:2.5 (M:F), and the antibody prevalence increased with age. This is the first report on the presence of hantavirus infections in Latvia, and the results indicate that two hantaviruses pathogenic to man, Saaremaa virus and Puumala virus, are widely distributed in this country.

Adult↗
PubMed2001

Prevalence of tick-borne encephalitis virus in Ixodes ricinus ticks in Finland.

Approximately 20 cases of tick-borne encephalitis (TBE) occur annually in Finland. The known endemic areas are situated mainly in the archipelago and coastal regions of Finland, with highest incidence in Aland islands. Ixodes ricinus panels collected in 1996-1997 from two endemic areas were screened for the presence of RNA. Two distinct RT-PCR methods were applied, and were shown to have an approximate detection limit of 10 focus forming doses (FFD)/100 microl. One out of 20 pools (a total of 139 ticks) from Helsinki Isosaari Island and one out of 48 pools (a total of 450 ticks) from Aland were positive with both methods, whereas the remaining pools were negative. The observed overall frequency (0.34%) in ticks in endemic areas of Finland, was similar to the low incidence found by virus isolation in mice in the 1960s (0.5%). Viral RNA was detectable in a diluted sample representing 0.005% of a positive pool of ten nymphs suggesting that the viral RNA load within an infected tick pool was approximately equivalent to 20,000-200,000 FFD. Sequence analysis did not show geographical clustering of the Finnish strains, suggesting an independent emergence of different TBE foci from the south. TBE virus RNA positive ticks were not found in I. ricinus panels consisting of 130 pools (726 ticks) from Helsinki city parks or 41 pools (197 ticks) from Võrmsi Island in Estonia.

Animals↗
PubMed2001

Characterization of tick-borne encephalitis virus from Latvia: evidence for co-circulation of three distinct subtypes.

Viruses of the tick-borne encephalitis (TBE) antigenic complex within the family Flaviviridae cause a variety of diseases, including uncomplicated febrile illness, meningoencephalitis, and hemorrhagic fever. Different domesticated animals or wildlife species often act as reservoir hosts and ixodid ticks serve as vectors. Although TBE is a serious problem in Latvia, the knowledge concerning TBE virus (TBEV) strains circulating in the country is most limited. Only two strains (Latvia-1-96 isolated from a TBE patient, and RK1424 originating from an Ixodes persulcatus tick), which belonged to the Siberian and the Far Eastern subtypes of TBEV, respectively, have previously been characterized. In the present study, we concentrated on the western and central regions of Latvia, with predominantly Ixodes ricinus ticks. Five virus strains were isolated from serum samples of patients with clinical symptoms of an acute TBE infection. Nucleotide sequences encoding the envelope (E) protein of TBEV, which were recovered from the five TBEV isolates, showed the highest level of identity to the corresponding sequences of the prototype strain Neudoerfl and other European strains of the Western TBEV subtype characterized previously. Accordingly, phylogenetic analysis placed the new Latvian isolates within the Western genetic lineage of TBEV. Taken together with earlier observations, the results proved that all three TBEV subtypes are co-circulating in Latvia and indicated that the genetic diversity of TBEV within certain geographical areas is much more complex than previously believed.

Encephalitis Viruses, Tick-Borne↗
PubMed2001

Tick-borne encephalitis virus in Lithuania.

Tick-borne encephalitis (TBE) is a severe problem in Lithuania, indicated by the 171 to 645 serologically confirmed cases that occurred each year between 1993 and 1999. In the present report, the first isolation and partial genetic analysis of a Lithuanian TBE virus (TBEV) strain isolated from a patient's serum sample is described. The patient was bitten by a tick while visiting the Lazdijai district (Veisiejai forest) in the southernmost part of Lithuania, a geographical area where Ixodes ricinus but not Ixodes persulcatus ticks are known to be present. The E protein-encoding viral gene sequence (nt 74-1273) recovered from the TBEV isolate showed the closest similarity to previously characterized European strains of the Western TBEV subtype, including the prototype TBEV strain Neudoerfl and those from neighbouring Latvia. Accordingly, the Lithuanian isolate was placed within the Western genetic lineage of TBEV in phylogenetic trees.

Adult↗
PubMed2000

Serological differentiation of murine typhus and epidemic typhus using cross-adsorption and Western blotting.

Differentiation of murine typhus due to Rickettsia typhi and epidemic typhus due to Rickettsia prowazekii is critical epidemiologically but difficult serologically. Using serological, epidemiological, and clinical criteria, we selected sera from 264 patients with epidemic typhus and from 44 patients with murine typhus among the 29,188 tested sera in our bank. These sera cross-reacted extensively in indirect fluorescent antibody assays (IFAs) against R. typhi and R. prowazekii, as 42% of the sera from patients with epidemic typhus and 34% of the sera from patients with murine typhus exhibited immunoglobulin M (IgM) and/or IgG titers against the homologous antigen (R. prowazekii and R. typhi, respectively) that were more than one dilution higher than those against the heterologous antigen. Serum cross-adsorption studies and Western blotting were performed on sera from 12 selected patients, 5 with murine typhus, 5 with epidemic typhus, and 2 suffering from typhus of undetermined etiology. Differences in IFA titers against R. typhi and R. prowazekii allowed the identification of the etiological agent in 8 of 12 patients. Western blot studies enabled the identification of the etiological agent in six patients. When the results of IFA and Western blot studies were considered in combination, identification of the etiological agent was possible for 10 of 12 patients. Serum cross-adsorption studies enabled the differentiation of the etiological agent in all patients. Our study indicates that when used together, Western blotting and IFA are useful serological tools to differentiate between R. prowazekii and R. typhi exposures. While a cross-adsorption study is the definitive technique to differentiate between infections with these agents, it was necessary in only 2 of 12 cases (16.7%), and the high costs of such a study limit its use.

Animals↗
PubMed2000

Characterization of tick-borne encephalitis virus from Latvia.

Viruses of the tick-borne encephalitis (TBE) antigenic complex, within the family Flaviviridae, cause a variety of diseases including uncomplicated febrile illness, encephalitis, meningo-encephalitis, hemorrhagic fever and chronic disease in humans, domesticated animals or wildlife species. TBE is a serious problem in Latvia with up to a 1,000 patients confirmed serologically annually 1994-1995. No previous data had been reported on the causative agent of TBE in Latvia. In the present study, a virus was isolated from serum of a patient with clinical symptoms of an acute TBE infection. Nucleotide sequence information obtained by direct reverse transcription-polymerase chain reaction (RT-PCR) and the serological characteristics of the isolated virus strain, designated TBE-Latvia-1-96, indicated a closer relationship to the Vasilchenko strain, isolated in Novosibirsk (Siberia, Russia), as compared to the western European or far eastern subtypes of TBE viruses. In a mouse neurovirulence assay, a significant difference in survival rates (days) was shown between Latvia-1-96 and the western European TBE virus subtype.

Animals↗
PubMed1999

[Three Swedish cases of African tick-bite fever. Can our native Rickettsia species cause disease in humans?].

The article consists in a report of three cases of African tick-bite fever in Swedish tourists returning from brief visits to South Africa. The clinical course included eschar, regional lymphadenopathy, fever and, in two cases, maculopapular rash. Two cases were characterised by significant increases in anti-Rickettsia conorii IgG and IgM antibody titres. However, the aetiological agent was assumed to be Rickettsia africae, based on reports by others and the widespread serological cross-reactivity among spotted fever Rickettsia spp. The third case was diagnosed on clinical grounds. During the past ten years, 50 per cent (41/80) of cases diagnosed serologically as rickettsial (R. conorii antigen) spotted fever at the Swedish Institute for Infectious Disease Control were associated with travel to South Africa. Parallels are drawn to the recent finding of R. helvetica in Swedish ticks (Ixodes ricinus), and the possibility of its pathogenicity to humans is discussed, though no such clinical cases have been reported to date.

Adult↗
PubMed1999

[Increased travelling--increased risk of imported viruses. A review of the diagnostic capacity of the Swedish Institute for Infectious Disease Control].

The increase in global travel, especially by air, has facilitated the spread of infectious agents from one part of the world to another. Returning travellers are often vectors for viral disease import to Sweden. While dengue fever has been quite frequently diagnosed during the past five years, especially in travellers returning from Thailand, only isolated cases of sandfly fever, Japanese encephalitis and Ross River fever have been seen. Dobrava virus was recently shown to have caused a severe form of haemorrhagic fever with renal syndrome in several European countries, and thus constitutes a risk for travellers to areas where it is endemic.

Communicable Disease Control↗
PubMed1999

African tick-bite fever imported into Norway: presentation of 8 cases.

We report on 8 Norwegian travellers to Southern Africa with African tick-bite fever (ATBF), a recently described spotted fever group rickettsiosis. All patients had acute flu-like symptoms and developed I or multiple inoculation eschars. The patients were treated with either doxycycline or ciprofloxacin, and all recovered. The diagnosis of ATBF was confirmed by the detection of specific IgM antibodies to Rickettsia africae by microimmunofluoroscence in convalescent-phase serum samples.

Antibodies, Bacterial↗
PubMed1998

[Spotted fever imported into Norway in 1997].

Tick-borne rickettsioses are important zoonoses in many tropical and subtropical areas. There has recently been an increase in the number of reported cases among tourists returning to Scandinavia. In this article we present all five serologically confirmed cases of tick-borne rickettsioses imported into Norway in 1997. The patients were Norwegian tourists who had visited South Africa (three cases), Zimbabwe, and Italy. Four cases had typical eschar and three had maculopapular exanthema. The patients were treated with either doxycycline or ciprofloxacin. No complications were reported. The diagnosis of tick-borne rickettsiosis was confirmed by the detection of specific IgM antibodies to Rickettsia conorii using micro-immunofluorescence in serum samples.

Adult↗
PubMed1998

A rapid fluorescent focus inhibition test for detection of neutralizing antibodies to tick-borne encephalitis virus.

Tick borne encephalitis (TBE), is endemic in several countries in central and northern Europe, in the Baltic states and in Russia. Vaccination has been shown to lower efficiently the number of cases of this potentially very serious disease. However, the possibility to assess the neutralizing antibody response after clinical disease or vaccination has been hampered by the lack of easy and specific tests. We developed a rapid fluorescent focus inhibition test (RFFIT) and compared it with a standard plaque reduction neutralization test (PRNT) and an hemagglutination inhibition test (HI) for antibody detection in late convalescent sera from 18 patients with a previous clinical and serological diagnosis of TBE. Neutralizing titres obtained with RFFIT were almost identical to those obtained with PRNT, and correlated also well with the HI results. The RFFIT for detection of neutralizing antibodies to TBE-virus has an advantage over the standard PRNT in its easy and rapid performance (results are obtained in 1 vs 7 days), and over the HI in its specificity, since cross-reactions with other flaviviruses are minimized.

Animals↗
PubMed1997

[Dengue fever imported to Norway. Serologically confirmed cases 1991-96].

With up to 100 million cases annually, dengue fever is today's most important arboviral disease. Dengue fever is endemic in many parts of South-East Asia, the Indian subcontinent, Oceania and the Americas. The disease mainly affects the local population, but occasionally also visitors from non-endemic areas. In this article we present epidemiological and clinical data on all 26 cases with serological confirmed dengue fever diagnosed in Norway in 1991-1996. 21 patients (81%) were infected in Asia. Typical exanthema, leucopenia, and thrombocytopenia were seen in 71%, 79% and 84% of the cases, respectively. A 37-year-old Indian-born woman developed dengue haemorrhagic fever grade 1 after a visit to New Delhi, while the remaining 25 patients had classical dengue fever. Postinfectious complications were common, and four weeks after the acute illness, hair loss, mental depression and asthenia were reported by 45%, 50% and 100% of the cases, respectively.

Adult↗
PubMed1997

[Q-fever imported into Norway].

Q fever is an important zoonosis that occurs throughout the world. In contrast to most other European countries, there has been no evidence of endemic Q fever in Norway up to now. The disease is caused by Coxiella burnetii, a rickettsia-like bacterium. Humans are infected mainly by inhalation of contaminated aerosols from cattle, sheep and goats. Clinical manifestations are protean, ranging from asymptomatic infection to life-threatening endocarditis. In this article we present the first four cases of serological proven acute Q fever imported into Norway. The patients were Norwegian tourists who had visited Bhutan, the Canary Islands, and Morocco. Two patients had fever with maculopapular exanthema, one had pneumonia, and one had biopsy-proven granulomatous hepatitis. Three were treated with tetracyclines. All four patients recovered well.

Aged↗
PubMed1997

[Endemic typhus imported to Norway].

Murine typhus, caused by Rickettsia typhi, is an important zoonosis in all parts of the world. The disease is transmitted from rodents to humans by fleas. In this article we describe the first three cases of serologically proven murine typhus imported into Norway during the 1990s. The patients were Norwegian tourists who had visited respectively Guinea-Bissau, Crete and Thailand. They all became acutely ill with fever, chills and severe headache 1-10 days after return to Norway. None of them had a rash. Two patients were admitted to hospital, and one was treated with ciprofloxacin for suspected typhoid fever. All the patients recovered without sequelae. The diagnosis of murine typhus was based on detection of IgM-anti-bodies against R typhi in serum samples during reconvalescence.

Adult↗