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Thirty-five field rabies virus strains were collected in recent years in different regions of the Russian Federation in order to characterize their genetic heterogeneity and to study their molecular epidemiology. In addition to the Russian viruses, seven archive samples from Estonia and Finland and two Russian vaccine strains were also included in the study. The viruses collected were subjected to two different reverse transcription-polymerase chain reaction tests, the amplicons were sequenced and the sequences were analysed phylogenetically. Among the field viruses studied, two main phylogenetic groups were found and designated as Pan-Eurasian and Caucasian according to their geographic origin. The Pan-Eurasian group, comprising some reference viruses from Europe, was further divided into four subgroups. All of the vaccine strains were clearly different from the field strains. No recombination between the field and vaccine virus strains was observed. The data obtained here show the critical role of geographical isolation and limitation for the genetic clustering and evolution of the rabies virus and also help in predicting its distribution from rabies-affected areas to rabies-free areas.

Eighty-four calves with respiratory disease from 18 herds in different parts of Finland were chosen for a study evaluating the capacity of different respiratory pathogens to cause changes in different acute phase protein concentrations, white blood cell (WBC) count and clinical signs. The selected acute phase proteins were fibrinogen, haptoglobin, serum amyloid-A, lipopolysaccharide binding protein and alpha1-acid glycoprotein. From each calf, a paired blood sample was obtained for serological studies of bovine parainfluenza virus-3, bovine respiratory syncytial virus, bovine coronavirus, bovine adenovirus-3 and bovine adenovirus-7. Tracheobronchial lavage was performed to detect bacteria and mycoplasma. Isolation of Pasteurella multocida was associated with increased concentrations of all tested acute phase proteins. For other pathogens, no significant relationships were observed. No association was present between viral or bacterial findings and WBC count.

Pathogens causing bovine respiratory tract disease in Finland were investigated. Eighteen cattle herds with bovine respiratory disease were included. Five diseased calves from each farm were chosen for closer examination and tracheobronchial lavage. Blood samples were taken from the calves at the time of the investigation and from 86 calves 3–4 weeks later. In addition, 6–10 blood samples from animals of different ages were collected from each herd, resulting in 169 samples. Serum samples were tested for antibodies to bovine parainfluenza virus-3 (PIV-3), bovine respiratory syncytial virus (BRSV), bovine coronavirus (BCV), bovine adenovirus-3 (BAV-3) and bovine adenovirus-7 (BAV-7). About one third of the samples were also tested for antibodies to bovine virus diarrhoea virus (BVDV) with negative results. Bacteria were cultured from lavage fluid and in vitro susceptibility to selected antimicrobials was tested. According to serological findings, PIV-3, BAV-7, BAV-3, BCV and BRSV are common pathogens in Finnish cattle with respiratory problems. A titre rise especially for BAV-7 and BAV-3, the dual growth ofMycoplasma disparandPasteurella multocida, were typical findings in diseased calves.Pasteurellasp. strains showed no resistance to tested antimicrobials.Mycoplasma bovisandMannheimia haemolyticawere not found.

Bulk milk samples from every herd supplying milk to dairies in Finland were examined for the presence of antibodies to BVD virus (BVDV) annually during 1993-1997. The highest prevalence, 0.99% in 1994, declined to 0.37% in 1996; however, this favourable trend appeared to discontinue in 1997, where the prevalence remained at 0.41%. In 1993, sera of all individual animals from bulk milk antibody-positive herds were examined for the presence of these antibodies. Since 1994, only sera of animals from herds with a bulk milk absorbance reading greater than 0.250 in the EIA test were examined individually. Three geographic foci of BVDV antibody-positive dairy herds were resolved in 1994, one in the north-western, another in the eastern and a diffuse third in the southern part of Finland. A distinct limiting of the spread was apparent in 1997. Beef cattle were also studied during 1993-1997; in 1993 breeding units, in 1994 mainly beef suckler herds and in 1995-1997 serum samples of beef animals at slaughter were examined for the presence of antibodies to BVDV. The prevalence of seropositive herds in 1993 and 1994 was 30.2% and 3.2%, respectively, while the prevalence among slaughter animals ranged 0.8-1.6%. Seronegative animals in herds with > 50% of seropositive animals were examined for the presence of BVD-virus. A total of 40 dairy herds and two beef herds with viraemic (persistently infected, PI) animals was encountered during 1993-1997. A comprehensive control programme and a more specific, cooperatively funded eradication programme for dairy cattle were launched in 1994. These programmes most probably contributed to the decline in prevalence during 1994-1996.

Five different rabies virus variants were identified among rabies virus-positive samples from Russia, Finland and Estonia, using a panel of five anti-nucleocapsid monoclonal antibodies. Two rabies virus isolates showed a different reaction pattern, suggesting the presence of a new antigenic variant. The results were compared with the data obtained by other research groups.

A total of 47 fish located in 10 lake and river systems in northern Finland were examined for furunculosis, enteric redmouth diseases (ERM), viral fish diseases and the parasite Gyrodactylus salaris. Furunculosis was found in 2 fish farms in different watercourses, ERM in 8 fish farms in 3 watercourses and viral diseases were not found at all. G. salaris was looked for only in salmon and rainbow trout and was found in both species in 3 farms belonging to 2 watercourses.

A modified first passage cell culture method, mouse inoculation test, and ELISA were compared for the detection of rabies in serially diluted field samples. Each original specimen contained rabies antigen, individually identified as an arctic strain by monoclonal antibodies. In 47% of the samples tested in cell cultures, the end-point titer was increased as a result of the first passage. The cell culture method gave higher titers than the mouse inoculation test or ELISA (P less than 0.05 and P less than 0.01, respectively).

We report a molecular epidemiological study of rabies in Arctic countries by comparing a panel of novel Greenland isolates to a larger cohort of viral sequences from both Arctic and Baltic regions. Rabies virus isolates originating from wildlife (Arctic/red foxes, raccoon-dogs and reindeer), from domestic animals (dogs/cats) and from two human cases were investigated. The resulting 400 bp N-gene sequences were compared with isolates representing neighbouring Arctic or Baltic countries from North America, the former Soviet Union and Europe. Phylogenetic analysis demonstrated similarities between sequences from the Arctic and Arctic-like viruses, which were distinct from rabies isolates originating in the Baltic region of Europe, the Steppes in Russia and from North America. The Arctic-like group consist of isolates from India, Pakistan, southeast Siberia and Japan. The Arctic group was differentiated into two lineages, Arctic 1 and Arctic 2, with good bootstrap support. Arctic 1 is mainly comprised of Canadian isolates with a single fox isolate from Maine in the USA. Arctic 2 was further divided into sub-lineages: 2a/2b. Arctic 2a comprises isolates from the Arctic regions of Yakutia in northeast Siberia and Alaska. Arctic 2b isolates represent a biotype, which is dispersed throughout the Arctic region. The broad distribution of rabies in the Arctic regions including Greenland, Canada and Alaska provides evidence for the movement of rabies across borders.

Enzootic bovine leukosis (EBL) was recognized among Finnish cattle in 1966. Administrative decisions specifying and refining official control measures were given in 1966, 1976, 1980, and 1993. The measures' key principle always has been 'test and slaughter'. The EBL/bovine leukosis virus (BLV) infection situation was monitored at meat inspection, and hematologically between 1970 and 1977 and serologically between 1978 and 1989. Annual surveys including all dairy herds and samples from beef animals were conducted in 1990-2001. Bulk-tank milk samples represented the dairy herds in the surveys; the beef animals were sampled individually at slaughter. The maximum positive herd-level percentage in the surveys was 0.03%. EBL/BLV infection was evenly dispersed in the southern part of the country and nonexistent in the northern part. We conclude that herd-level prevalence of EBL/BLV infection never exceeded 5%. It nevertheless took 30 years to eradicate the disease and the infection. EBL was eradicated from mainland Finland in 1996 and from the island district of Ahvenanmaa in 1999. Annual monitoring of the EBL situation continues.

Forty-seven healthy, owned dogs were vaccinated with Madivak and 85 with Rabisin. Geometric mean titres of 17.40 and 1.03 IU/ml were measured by the rapid immunofluorescent focus inhibition test 30–40 and 350–370 days, respectively, after a single injection. Four out of 130 (3.1%) and 18 out of 106 (17% ) dogs had a titre of less than 0.5 IU/ml in serum 30–40 and 350–370 days after vaccination. Twenty-one dogs (19.8%) had a titre of 0.5 IU/ml 350–370 days after vaccinaton. There was no significant difference in antibody levels between animals vaccinated with Rabisin or Madivak. Our results indicate that a booster is always necessary after a single injection to ensure that all dogs have a lasting antibody titre.

Twenty-one heads of cattle were vaccinated with Madibovin, 31 with Rabdomun and 127 with Rabisin on 4 different farms. Rabies neutralizing antibody titre (or = 0.5 IU/ml) was detected in 80% of 163 animals tested about 1 month and in 42% of 133 animals tested about 1 year after primary vaccination. On 3 of the farms 86 animals received booster vaccination about 1 year after primary vaccination. All these animals had antibody titre (or = 0.5 IU/ml) about 1 month after booster and antibody levels were higher than after the primary vaccination. Rabies antibody titres (or = 0.5 IU/ml) were detected in 96% of 50 animals tested 1 year after the booster. No significant differences (p0.05) in antibody levels were detected between animals vaccinated with Madibovin or Rabisin (farm C) respectively with Rabisin or Rabdomun (farm D) at any collection time. Responses to rabies vaccines varied considerably between the farms. After primary vaccination of the animals on 2 farms with the same batch of Rabisin, the antibody levels clearly differed (p0.0001) between the farms. Our results indicate that booster is always necessary after primary vaccination to ensure that all animals are protected.

When rabies reappeared in Finland in April 1988, the country had been rabies free since 1959. Soon a picture of sylvatic rabies become evident, its main vector and victim being the raccoon dog (Nyctereutes procyonoides). Between 8 April 1988 and 16 February 1989, 66 virologically verified cases were recorded (48 raccoon dogs, 12 red foxes, 2 badgers, 2 cats, 1 dog and 1 dairy bull) in an area estimated at 1700 km2 in south-eastern Finland. The greatest distance between recorded cases was 67 km. A positive reaction with monoclonal antibody p-41 indicated that the virus was an arctic-type strain. A field trial on oral immunization of small predators was initiated in September 1988 using Tübingen fox baits according to the Bavarian model of bait distribution. Each bait contained 5*10(7) TCID50/ml modified live rabies virus (SAD-B19). The 6 months' surveillance indicate a seroconversion rate of 72% (N = 126) in the raccoon dog population, 67% (N = 56) in the red foxes and 13% (N = 16) in the badgers, when titers greater than or equal to 1.0 IU/ml are considered seropositive. In the whole follow-up period, no statistically significant difference could be detected between the raccoon dogs and red foxes in the rate of seroconversion or in the uptake of tetracycline from the baits. Notably high antibody levels were recorded in both raccoon dogs and red foxes within 4-5 months after vaccination. Of the seropositive animals, the proportion of animals with titers 3.0 IU/ml or greater was higher in raccoon dogs (73%) than in red foxes (51%) (x2 = 5.29, p less than 0.05). The trial shows that raccoon dogs can be immunized against rabies in the field with vaccine baits originally developed for controlling sylvatic rabies in foxes.

Serum samples from cattle and reindeer in Lapland were examined for neutralizing antibodies to the IBR/IPV virus. All the bovine sera tested were negative. The reindeer sera were tested using 2 different virus neutralization methods differing in the serum-virus incubation time prior to inoculation into tissue culture tubes. 12.6 % of the samples tested with a preincubation of 1 h at 37°C were positive, whereas 23 % of those tested with a preincubation time of 24 h at 37°C were positive. The fairly high prevalence of antibodies to IBR/IPV in the reindeer population in Finland indicates the occurrence of the IBR/IPV virus or a closely related cross-reacting herpesvirus.

Using the immunodiffusion method, antibodies against human wart-virus were detected in dog, pig and cattle sera but not in horse and reindeer sera. Antibodies were found in 25 per cent (28/114) of the dog sera, the prevalence of antibodies being fairly similar to that in children of the same age. By electron microscopy the antibodies in dog sera were shown to attach to and precipitate the human wart-virus particles, and in immunodiffusion the precipitation lines of human and dog sera were shown to be identical. Of the cattle sera studied, 10 per cent (10/97) and of the pig sera 13 per cent (5/40) gave a faint precipitation line, having identity with that given by the human sera, against human wart-virus. Conversely 18 per cent (9/50) of adult human sera contained precipitating antibodies against a bovine papilloma antigen, probably bovine papilloma virus.

The clinical findings are described in the first reported European case of fatal encephalitis of bat origin caused by a rabies-related virus. A bat zoologist developed the symptoms of rabies 51 days after his last exposure to a bat bite. The clinical disease of 23 days duration was a combination of the paralytic and 'furious' forms of rabies. Serial BAEP and EEG recordings, CT and MR scans of the brain, as well as CSF findings, demonstrated severe ascending destruction of the brain. An unusual progression from isolated brainstem death to cortical brain death occurred. Neuropathologically, the brain showed severe lytic changes. The presence of rabies-related virus antigens in brain smears was shown using a panel of fluorescent antibodies. The virus was inoculated into and isolated from suckling mice. The virus had a close resemblance to European bat rabies isolates, which belong to the group of rabies-related viruses. Of particular concern is whether the virus can spread from bats to terrestrial animals and whether the European type of bat rabies constitutes a danger to man.

A latex agglutination (LA) test for the detection of parvoviruses of fur animals, cats, and dogs was developed, and its sensitivity and specificity were compared with those of hemagglutination (HA) and the enzyme-linked immunosorbent assay (ELISA). Tissue culture isolation was used to confirm the specificity results. Fecal samples from various sources were tested, including specimens from raccoon dogs and mink which were experimentally infected with parvoviruses by oral exposure. LA compared favorably with the other tests. The ELISA was the most sensitive. When it was considered as a reference test, the corresponding sensitivities for HA and LA were 96 and 91%, respectively. The specificities were 93% for the ELISA, 95% for the HA test, and 92% for the LA test. LA seems to be a suitable technique for screening animals in the field and in laboratories in which sophisticated techniques are not available.

The occurrence of group specific complement fixing antibodies was studied in 361 cattle sera from 36 herds in 6 areas in Finland. Sixty-two (17.2%) were positive. The antibody frequency increased significantly from the south to the north and the frequency was significantly higher in forest than in field pastures. The reasons for the differences are discussed. The tick, Ixodes ricinus, perhaps has no significant epidemiological role in chlamydial epidemiology in Finland.

In 1974, a very extensive influenza/A/equi 2 epidemic broke out in the Finnish horse population. To study the efficacy of influenza vaccinations a questionnaire was sent after the epidemic to all Finnish veterinarians. The answer material was selected to contain only stables which had had clinically typical cases. The material consisted 234 unvaccinated and 629 vaccinated horses. In the latter group 466 horses were vaccinated adequately. The results of the study showed that of the unvaccinated horses 212 (91%) and of the adequately vaccinated horses only 42 (9.4%) contracted clinically typical influenza. On the other hand, in the group of horses vaccinated irregularly or only once before the epidemic the disease prevalence was about the same as for the unvaccinated animals. Thus, the equine influenza vaccines used in Finland had a surprising good efficacy if they were used according to instructions.

An outbreaks of severe enteritis occurred among young raccoon dogs on fur farms in eastern Finland. Post mortem examinations revealed gross and microscopic lesions which were typical of parvovirus infections described in cats, mink and dogs. The intestine was dilatated, oedematous and the normal villi were significantly reduced. A parvovirus was isolated from faeces and found to resemble canine parvovirus by its ability to haemagglutinate pig erythrocytes at pH 7.2 and its antigenic properties. Experimental inoculations showed that both housed raccoon dogs and foxes are susceptible.

The occurrence of group specific complement fixing antibodies was studied in random sera of cattle and reindeer in Finnish Lapland. Sixty-eight (40.5%) of the 168 cattle sera were positive. Sixty 4hree (21.6 %) of the 291 reindeer sera were positive. The difference is statistically nearly significant in the t-test. The antibody titer ≥ 1:16 was regarded as positive. The antibody frequency of cattle sera was statistically significantly higher and the antibody frequency of reindeer sera was nearly significantly higher than in earlier studies on cattle sera in South and Central Finland. The reasons are discussed.

A serological survey on the occurrence of group-specific chlamydial antibodies in random sera of Finnish sheep, cattle and horses was performed. The whole material consisted of 1347 serum samples, including 432 ovine, 454 bovine and 461 equine sera. The sera were sent to the laboratory for various serological tests during 1968–1972. Of the ovine sera 9.5%, bovine 12.8 % and equine 7.1 % showed a titer ≥ 1:16 in the complement fixation test. No definite geographic differences could be found in the distribution of the herds which showed positive results. The ubiquity of chlamydial infections in domestic mammals and their role as a cause of clinical diseases is discussed.

Sukura, A. and E. Neuvonen: Latex test for rapid rotavirus diagnosis in calves. Acta vet. scand. 1990, 31, 1–4. - A latex agglutination test (LA) was compared with direct electron microscopy (EM) for detection of rotavirus infection in calves. A total of 375 samples from 62 calves were collected. Samples were taken when the calves were 1, 3, 5, 7, 10 and 20 days old and some scours samples were collected as well. Altogether 45/375 (12%) specimens were positive in LA and 10/375 (2.7%) were positive in EM. Samples positive in EM were also positive in LA. Out of the 62 calves studied 26/62 (42%) were positive in LA and 8/62 (13%) in EM. We found the LA very easy to perform, to be more sensitive than the EM method and probably a rather specific method for detection of rotavirus infection.