Tick-borne encephalitis: Possibly a fatal disease in its acute stage. PCR amplification of TBE RNA from postmortem brain tissue

Summary Tick-borne encephalitis has occurred regularly in Europe since it was first diagnosed in 1931 bySchneider. The mortality rate of patients with this disease is 1–2%. Death usually occurs in the acute stage of illness. A case report of a 28-year-old patient from Slovenia, who died shortly after the onset of tick-borne encephalitis, is described. The clinical course of disease, results of serological tests, neuropathological findings and polymerase chain reaction amplification of parts of viral genome from postmortem brain tissues are presented.     

Evaluation of immunofluorescence test (IFT) and immuno (western) blot (WB) test in patients with erythema migrans

The diagnosis of Lyme borreliosis is based on the recognition of typical clinical signs and is assisted by laboratory confirmation of borrelial infection. The aim of the present study was to assess the value of an immunofluorescence test (IFT) and an immuno (western) blot (WB) test for the detection of Borrelia burgdorferi sensu lato antibodies in patients with erythema migrans residing in Slovenia. We determined specific IgM and IgG antibodies in 117 patients with erythema migrans and 96 healthy persons using an IFT (in-house test) and a commercial WB test. Skin biopsies of erythema migrans lesions were cultured, and isolated strains were identified with PFGE. There were 66/117 (56.4%) culture-positive and 51/117 (43.6%) culture-negative patients. B. afzelii was found in 52/62 (84%) and B. garinii in 10/62 (16%) biopsies. IFT-IgM antibodies were established in 2/117 (1.7%) erythema migrans patients and in none of the control group, while WB-IgM antibodies were present in 56/117 (48%) patients with erythema migrans and 21/96 (22%) members of the control group (p = 0.002). IFT-IgG antibodies were demonstrated in 3/117 (2.2%) erythema migrans patients and 2/96 (4%) persons of the control group, while corresponding values for WB-IgG were 36/117 (31%) and 26/96 (27%), respectively (non-significant differences). IgM antibodies directed against p41 and OspC, and IgG antibodies directed against p41, p18 and OspC were frequently found in both erythema migrans patients and the control group. The only significant difference between erythema migrans patients and the control group in the WB test was in the reaction of IgM antibodies with OspC antigen, which was found in 54/117 (46%) erythema migrans patients and 18/96 (18.8%) healthy persons (p < 0.0001). The immune response in patients with erythema migrans was very similar to that of the control group determined with either the IFT or WB test.     

Development of erythema migrans in spite of treatment with antibiotics after a tick bite

OBJECTIVES: The recent information on the appearance of erythema migrans despite prophylaxis with 200 mg of doxycycline was the stimulus for a search among our patients for those who developed the skin lesion regardless of receiving antibiotics after a tick bite. METHODS: Data were reviewed for adult patients with erythema migrans diagnosed at our institution from 1994 to July 2001, targeting those who received antibiotics after a tick bite. RESULTS: Seven of 5056 (0.14%) patients, diagnosed with typical erythema migrans, developed the skin lesion despite receiving antibiotics after a tick bite. Antibiotics were prescribed by general physicians: in four cases as prophylaxis of Lyme borreliosis within one day after tick detachment and in three cases because of development of acute respiratory tract infection two, five, and eight days after the bite, respectively. The dosages were as follows: azithromycin in a total dose of 3 g in three patients and 1.5 g in the fourth patient, amoxicillin-clavulanic acid 625 mg t.i.d. for ten days in the fifth patient, amoxycillin 500 mg t.i.d. for seven days followed by azithromycin 250 mg o.d. for eight days in the sixth, and amoxycillin 500 mg t.i.d. for eight days in the seventh. The patients (five females and two males, aged 18-61 years) were referred to our Department on average six (1-19) days after the appearance of skin lesions. They had typical solitary (five patients) or multiple (two patients) erythema migrans with the characteristics usually seen in European patients, except for a rather long incubation period (median value 28 days, range 10-40 days). All laboratory tests, including the examination of cerebrospinal fluid in three patients with the disseminated form of the illness, were within normal range. Borrelial antibodies were demonstrated in only one patient. A skin biopsy specimen obtained from the site of the erythema migrans was culture positive for Borrelia in 2/4 patients. CONCLUSIONS: Our study did not enable us to assess the frequency of antimicrobial prophylaxis failure or the efficacy of individual antibiotics for the prevention of Lyme borreliosis. However, the seven patients presented demonstrate that antibiotic prophylaxis for Lyme borreliosis after a tick bite, at least in Europe, is not entirely effective.     

Double infection with tick borne encephalitis virus and Borrelia burgdorferi sensu lato

The limited information on co-infection with Borrelia burgdorferi sensu lato and tick-borne encephalitis (TBE) virus was a stimulus for presentation of two patients with well-defined double infection of the central nervous system. TBE virus and B. burgdorferi sensu lato infections are searched for in all patients with lymphocytic meningitis and/or meningoencephalitis admitted to our department. During the last ten years we identified two patients who had ELISA IgM and IgG antibodies to TBE virus in serum and a positive PCR result for TBE virus in cerebrospinal fluid as well as B. burgdorferi sensu lato isolated from cerebrospinal fluid. Intrathecal production of borrelial antibodies was not proven in either of the two patients. These findings show that in patients with acute lymphocytic meningitis originating in regions endemic for Lyme borreliosis and TBE, the possibility of concomitant infection should be considered.     

Epidemiology of myotonic dystrophy type 1 (Steinert disease) in Belgrade (Serbia)

The aim of this study was to estimate the incidence and prevalence of myotonic dystrophy type 1 (DM1) in Belgrade during the period 1983–2002.

The patients who had DM1 were ascertained through hospital records from all neurological departments in Belgrade during 1983–2002. The molecular genetic analysis was performed in all patents included in the study.

We identified 101 DM1 patients (52 males and 49 females). The average annual incidence rate of DM1 in Belgrade for the period observed was 2.0/1,000,000 (95% confidence interval (CI), 0.3–8.3), 2.1/1,000,000 (95% CI, 0.3–8.3) for males and 2.0/1,000,000 (95% CI, 0.3–8.3) for females. The highest age-specific DM1 incidence was registered in the age group 20–49: 3.4/1,000,000 (95% CI, 0.5–7.6), 4.0/1,000,000 (95% CI, 1.1–10.2) in males and 2.5/1,000,000 (95% CI, 0.5–7.6) in females. In the population of Belgrade, a cumulative probability of acquiring DM1 was 1 per 8621 for men and 1 per 9259 for women (1 per 8940 of the population for both sexes). The prevalence of DM1 in Belgrade on 31 December 2002 was 5.3/100,000 (95% CI, 4.2–6.6).     

Efficacy of an inactivated FeLV vaccine compared to a recombinant FeLV vaccine in minimum age cats following virulent FeLV challenge

The aim of the study was to determine the efficacy of an inactivated feline leukemia virus (FeLV) vaccine (Versifel^® FeLV, Zoetis.) compared to a recombinant FeLV vaccine (Purevax^® FeLV, Merial Animal Health) in young cats, exposed under laboratory conditions to a highly virulent challenge model. The study was designed to be consistent with the general immunogenicity requirements of the European Pharmacopoeia 6.0 Monograph 01/2008:1321—Feline Leukaemia Vaccine (Inactivated) with the exception that commercial-strength vaccines were assessed. Fifty seronegative cats (8–9 weeks old) were vaccinated subcutaneously on two occasions, three weeks apart, with either placebo (treatment group T01), Versifel FeLV Vaccine (treatment group T02), or Purevax FeLV Vaccine (treatment group T03) according to the manufacturer's directions. Cats were challenged three weeks after the second vaccination with a virulent FeLV isolate (61E strain). Persistent FeLV antigenemia was determined from 3 to 15 weeks postchallenge. Bone marrow samples were tested for the presence of FeLV proviral DNA to determine FeLV latent infection. At week 15 after challenge with the virulent FeLV 61E strain, the Versifel FeLV Vaccine conferred 89.5% protection against FeLV persistent antigenemia and 94.7% protection against FeLV proviral DNA integration in bone marrow cells. In comparison, the Purevax FeLV Vaccine conferred 20% protection against FeLV persistent antigenemia and 35% protection against FeLV proviral DNA integration in bone marrow cells following challenge. The data from this study show that the Versifel FeLV Vaccine was efficacious in preventing both FeLV persistent p27 antigenemia and FeLV proviral DNA integration in bone marrow cells of cats challenged with this particular challenge model under laboratory conditions and provided better protection than Purevax FeLV in this experimental challenge model with highly virulent FeLV.