There was a general decline in animal rabies in Europe in 1991 following the peak levels which occurred
in 1989. This was ascribed, in France at least, to the normal decline in cases usually experienced following
peak occurrence and also to oral immunization of foxes against rabies.
European countries in which rabies occurs may be infected by fox, insectivorous bat or dog rabies. This
paper makes a general summary of the rabies situation in Europe in 1991 and presents data obtained
in 1991 from 15 European countries using oral vaccination against fox rabies.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. 
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Aubert, M.F.A.

Barrat, J.

Rabies in Southern and Eastern Africa. Workshop. (1993, Pretoria, South Africa)

The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. 
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.There was a general decline in animal rabies in Europe in 1991 following the peak levels which occurred
in 1989. This was ascribed, in France at least, to the normal decline in cases usually experienced following
peak occurrence and also to oral immunization of foxes against rabies.
European countries in which rabies occurs may be infected by fox, insectivorous bat or dog rabies. This
paper makes a general summary of the rabies situation in Europe in 1991 and presents data obtained
in 1991 from 15 European countries using oral vaccination against fox rabies.mn201

UPSpace at the University of Pretoria

Onderstepoort Journal of Veterinary Research, 60:357-364 (1993) Current status of fox rabies in EtJrope J. BARRAT and M.F.A. AUBERT CNEVA, Laboratoire 0' Etudes sur Ia Rage et Ia Pathologie des Animaux Sauvages B.P. 9, 54220, Malzeville, France ABSTRACT BARRAT, J. & AUBERT, M.F.A. 1993. Current status of fox rabies in Europe. Onderstepoort Journal of Veterinary Research, 60:357- 364 There was a general decline in animal rabies in Europe in 1991 following the peak levels which occurred in 1989. This was ascribed, in France at least, to the normal decline in cases usually experienced follow-ing peak occurrence and also to oral immunization of foxes against rabies. European countries in which rabies occurs may be infected by fox, insectivorous bat or dog rabies. This paper makes a general summary of the rabies situation in Europe in 1991 and presents data obtained in 1991 from 15 European countries using oral vaccination against fox rabies. RABIES SITUATION IN EUROPE IN 1991 TABLE 1 Animal rabies cases in Europe in 1991 a There are a number of animal reservoirs of rabies in Europe: red fox (Vulpes vulpes), polar fox (A/apex lagopus), dog and insectivorous bats (mainly Eptesi-cus serotinus). Some of the data presented here is derived from the Rabies Bulletin Europe published at the World Health Organization (WHO) Collaborating Centre in Tubingen, Germany. In 1989 there had been a general increase in fox ra-bies cases in Europe (principally in France, Belgium and Germany) which was interpreted as being the consequence of two mild winters which favoured the survival of foxes and their prey, resulting in an in-crease in the fox population and the occurrence of rabies. In 1991, 16 490 cases of rabies were reported in Eu-rope, which was 22% less than in 1990 (Table 1). However, this downward trend in cases was not evi-dent in Austria, Poland, Romania and Switzerland. Such an overall decrease in incidence is to be ex-pected after a period marked by a very high occur-rence of rabies, but the most significant decreases were recorded in the countries where oral vaccination No. of Country cases reported Austria 2 460 Belgium 29 Czechoslavakia 1 359 France 2 165 Germany 3 602 Hungary 880 Italy 4 Luxembourg 16 Netherlands (bat rabies cases) 12 Poland 2 287 Romania 54 Spain (African part) 8 Switzerland and Liechtenstein 105 Turkey (canine rabies principally) 427 USSR (canine rabies principally) 2 404 Yugoslavia (canine rabies 669 principally) a Data extracted from Rabies Bulletin Europe b NS = Not significant Trend (%) since 1990 NSb -75 NS -27 - 35 - 19 + 100 - 75 - 46 + 12 + 10 NS + 105 -27 + 35 - 20 357 Current status of fox rabies in Europe FIG. 1 Rabies distribution in Europe in 1991. Each point corresponds to a case of rabies in a terrestrial mammal. Bat rabies cases are indicated by squares. This map was edited from the quarterly maps published by WHO collaborating centre in Tl.ibingen (FRG) TABLE 2 Trend in rabies incidence between 1990 and 1991 in French departements vaccinated at least once during or before autumn 1990 Species 1990a 1991a Trend(%) Red foxes 515 123 - 80 Total wildlife cases 524 129 -80 Dogs 5 2 -Cats 9 3 -Cattle 17 5 - 70 Sheep and goats 40 4 - 90 Total domestic animal cases 73 15 -79 Total 597 144 -80 a These data were collected in the departements of Ain, Cher, Eure, Nievre, Rhone, Saone et Loire, Seine et Marne, Yvel ines and Val d'Oise (total area 4 7 123 km2) 358 campaigns had been undertaken. Switzerland was the exception to this trend. There, fox populations had increased following earlier oral immunization campaigns only to be followed by the re-introduc-tion of rabies from a neighbouring country. Fifteen cases of bat rabies were recorded in Europe in 1991: 12 in the Netherlands and three in Germany. Most of these occurred in areas where no fox rabies is present. As was the case for rabies in terrestrial animals, fewer cases in bats were reported in 1991 than 1990 (22 cases) or 1987 (142 cases). The dis-tribution of rabies cases in animals in Europe is shown in Fig. 1. No human rabies was reported in 1991. Influence of oral vaccination campaigns on fox rabies Data from France show that country-wide oral vacci-nation campaigns induced a decrease in fox rabies TABLE 3 Trend in rabies incidence between 1990 and 1991 in French departements never vaccinated prior to the autumn of 1990 Species 1990a 1991a Trend(%) Red foxes 313 333 +6 Total wildlife cases 325 356 + 10 Dogs 11 12 +9 Cats 21 23 + 10 Cattle 11 19 + 73 Sheep and goats 27 67 + 148 Total domestic animal cases 77 130 + 69 Total 402 486 + 21 a These data were collected in departements of Haute Marne, Bas Rhin, Haute Saone and Vosges (total area = 22 200 km2) as well as in other species. Table 2 summarizes the difference in incidence between 1990 and 1991 in departements (an administrative division of nearly 5 000 km2) in which bait vaccine was distributed throughout the departement at least once during or before autumn 1990, while Table 3 shows the trend in departements never vaccinated before autumn 1990. The general trend between 1990 and 1991 was an increase of 21 % in unvaccinated departements while an 80% decrease was experienced in vaccinated ones. It is furthermore probable that the better sur-veillance of fox rabies during oral immunization cam-paigns resulted in a higher proportion of rabies ca-ses in these animals being reported in vaccinated departements than in unvaccinated departements. In unvaccinated departements, the increase in rabies incidence was more marked in domestic than in wild animals. These departments have been infected with rabies for a long time and for this reason rabies in wildlife does not draw much attention and the pre-sence of rabies is therefore better indicated by the pres~nce of the disease in domestic animals. Another way of estimating the efficiency of oral vac-cine of foxes is to measure the number of rabies ca-ses/km2 of vaccinated area following oral immuniza-tion. Fig. 2 shows cumulative data collected between 1989 and October 1991 . Before oral vaccination of foxes, rabies case density was 16/1 000 km2. The occurrence of rabies was then measured during the 6 month periods including and following oral vac-cination campaigns (i.e. from November to the next April and from May to October) . Where no rabies case were identified in an area following a vaccination campaign, this zone was not included in the calculations, so it may be assumed that the decrease in rabies cases was more marked following oral immunization than indicated by Fig. 2. J. BARRAT & M.F.A. AUBERT 0,020-,-------------------, 1: o,o15 ~ Gl (/) ~ 0,010 (/) Gl :c ~ 0,005 - 55 % -74 % - 89 % - 97 % - 98 % ·l ' ···\l after 1st after 2nd after 3rd after 4th after 5th Oral vaccination campaigns FIG. 2 Evolution of rabies case density in areas submitted to oral vaccination campaigns from 1989 to October 1991. Data are grouped by six month periods (November to next April and May to October) Control of foxes rabies in Europe Prior to the meeting on Rabies Control in Europe, held in Nancy (France) in 1991 , a questionnaire was sent to heads of national veterinary services of all European countries. Twenty-five countries provided answers to the questionnaire. The answers indicated that 16 made an effort to control fox numbers while 15 were using oral vaccination of foxes. Furthermore, the area covered by oral vaccination campaigns in Europe has increased steadily: 55 000 km in 1988, 178 000 in 1990 and 269 000 in 1991. Conclusions based on data derived from answers to the questionnaire are summarized below and details shown in Tables 4-14. Status of oral vaccination of foxes • Eleven of the responding countries which are using oral immunization still consider the measure experimental despite large areas being covered in some cases (Tables 5 and 7). Financial support of these operations is both governmental and reg-ional and the participation of the EEC was indica-ted by three countries (Table 5) . With the excep-tion of Czechoslovakia, state agents distribute or participate to the distribution of baits in all Euro-pean countries. • Bait vaccines are distributed by hand on the ground exclusively by four countries, three others use only aerial distribution while three countries are using both methods. Among aerial distribution techniques, helicopters are most frequently used (Table 6) . • The density of baits distributed in treated areas is between 13 and 20/km2 but is not always homoge-neous; in six countries the density of distributed baits varies with the topography (Table 6). Two 359 Current status of fox rabies in Europe TABLE 4 Control measures used against rabies in wildlife in Europe: 1991 Fox Country Offensive Vacci-measures Culling nation Germany Yes s Yes United Kingdom No No Austria Yes S, G, P T Yes Yes Belgium Yes s Yes Yes Cyprus Yes S, P No No Denmark Yes No Spain No No Finland Yes S, T Yes No France Yes S, T Yes No Greece Yes S, T Yes Netherlands Yes s Yes Yes Hungary Yes s Yes Ireland No No Italy Yes s Yes Yes Luxembourg Yes s Yes Norway No Poland No No Portugal No Romania No Sweden Yes S, T Yes No Switzerland Yes Yes No Czechoslovakia Yes s Yes Yes Turkey USSR Yes s Yes Yes Yugoslavia Yes S, T Yes Yes S = shooting; P = poisoning; T = trapping; G = gassing TABLE 5 Financial support of oral vaccination campaigns in Europe: 1991 Experimental Main Other Country oral vacci- financial sources• nation support Germany Yes R/L United Kingdom No Austria Yes R Belgium Yes C/R Cyprus No Denmark No Finland Yes c France Yes C/R EEC Netherlands Yes c EEC Hungary No Italy Yes R Luxembourg Yes c Poland No Portugal No Romania No Sweden No c Switzerland Yes C/R Czechoslovakia Yes c EEC Yugoslavia Yes UEEBb C = central origin; R = regional origin; L = local origin a The EEC reimburses up to 50 % of money spent on oral vaccination of foxes in some circumstances b Union Europ. Elev. de Betail 360 Other wild species Vacci-Bounty Species Culling nation Bounty No No No No No No No No No No Yes Racoon dogs S, T Yes No No No No No No No No No No No No No No No No No No No No campaigns are conducted each year, one in spring and the other in autumn (Table 6) . Four vaccine viruses are incorporated into baits used in Europe. Three are attenuated strains (SAD Bern, SAD B19 and SAG1) and the fourth is a vaccinia/rabies-glycoprotein recombinant (VRG strain) (Table 8). • Assessment of the efficiency of oral vaccination of foxes is conducted both by surveys of rabies cases in treated areas (11 countries) and by ex-amination of specially sampled foxes in these areas (0,01 to 0,75 animals/km2) in ten countries (Table 9). Bait intake is measured by the deposition in bone and teeth of tetracyclin used as a biomarker in the baits. The detection of the marker is perform-ed by uv fluorescence of tooth sections (three countries), sections of lower jaw (eight countries) or femur (two countries) (Table 11). • Seroconversion is measured in ten countries by serum/virus neutralization tests on the sera of sampled animals, while an ELISA technique is used by one country (Table 9). • The possibility of the vaccine virus inducing rabies in foxes or other wildlife is tested by the use of monoclonal antibodies able to distinguish the vac-cine from street strains (Table 9). J. BARRAT & M.F.A. AUBERT TABLE 6 Distribution of bait vaccines in Europe: 1991 Distribution Country Distributing No. of Season Untreated areas teams baits/km2 On foot By air Germany F P, H 0 15-20 Spring/autumn Austria F V, 0 16 Spring/autumn Cities, water, mountains Belgium - P, H V, 0 15 Spring/autumn Finland F p V, 0 15 on foot, Spring/autumn Only border regions vaccinated 20 by air France - H 0 13 Spring/autumn Residential areas Netherlands F V, 0 16 Spring/autumn Cities Italy F + V, 0 5-20 Spring/autumn Luxembourg - H 0 20 Spring/autumn Switzerland F V, 0 15 Spring/autumn Alt.> 2000m Czechoslovakia F H v 15 Yugoslavia F V, 0 16 Spring/autumn F = foot; P = aeroplane; H = helicopter; V = volunteers; 0 = official agents; + = unknown TABLE 7 Areas over which bait vaccines against rabies in foxes were distributed in Europe: 1988-1990 TABLE 8 Vaccine strains incorporated into oral baits for immuni-zation of foxes in Europe Treated area (km2) Usage (% per annum) Country 1988 1989 1990 Country SAD SAD B19 SAG1 VRG Bern Germany 18 000 94 000 93 000 Germany 100 Austria 9 800 16 000 25 000 Austria. 100 0 0 0 Belgium 9 500 10 000 10 000 Belgium (1991) 100 Finland 2 825 9 700 2 000 Finland 100 France 4 626 28 305 106 518 France (1990) 42 19 39 0,9 Netherlands 260 260 260 Italy (1987) 5 392 2 370 Luxembourg 2 587 2 587 2 587 Switzerland 7 252 7 822 10 334 Czechoslovakia 3 307 14 520 Netherlands 100 0 0 0 Italy 100 Luxembourg 100 0 0 0 Switzerland (1990) 100 Switzerland (1991) 100 Czechoslovakia 100 Yugoslavia 580 3 500 4 500 Yugoslavia 100 TABLE 9 Details of methods employed by European countries in the monitoring of oral vaccination campaigns Differentiation No. of foxes No. of Tetracycline detection Sero- Other between rabies virus Country collected/km2 laboratories logical serology and vaccine strains involved technique In teeth In bones Tested Technique Germany 0,025 Lower jaw FFI3 Yes Mabs Austria 1 Lower jaw FFI No Belgium 0,040 1 Lower jaw FFI Vaccinia Nob Finland 0,008 1 Yes Lower jaw FFI Yes Mabs France 0,011 1 Yes Lower jaw FFI Yes Mabs Netherlands 0,750 1 Femur FFI No Italy 0,100 3 Lower jaw FFI Yes Mabs Luxembourg 0,100 1 Yes FFI No Switzerland 0,100 1 No Femur ELISA Yes Mabs Czechoslovakia 0,900 1 No Lower jaw FFI Yes Mabs Yugoslavia 2,000 1 Lower jaw FFI No a FFI = flourescent focus inhibition test b The use of VRG vaccine eliminates this risk 361 Current status of fox rabies in Europe TABLE 1 0 Studies conducted in parallel with oral vaccination control On other species Country On foxes Yes/No Tetracycline Other subjects Germany Population dynamics No Austria No No Belgium Population dynamics & echinococcosis Yes Yes Finland No Yes Biology of raccoon dog, game density France Population dynamics Yes Yes Netherlands No Yes Yes Luxembourg Echinococcosis & trichinellosis No Switzerland Population dynamics Yes Yes Population dynamics Czechoslovakia Bait intake at day 4, 8 and 14 Yes Yes Yugoslavia No Yes Yes Wild boar TABLE 11 Results obtained during oral vaccination campaigns in various European countries Cam- Bait intake (%)a Seroconversion Country Vaccinated paign (%)b species no. Min. Ave. Max. Min. Germany Fox 60 80 90 50 Austria Fox 1 55 60 47 Fox 2 70 80 59 Fox 3 70 80 59 Belgium Fox 1 53,5 Fox 2 41 Fox 3 73 Adult fox 4 86 Young fox 4 25 Finland Racoon dog 1 75 Racoon dog 2 50 Fox 1 Fox 2 Fox 3 Fox 4 France Fox 1 44 Fox 2 62 Fox 3 70 Fox 4 80 Netherlands Fox 1 46 Fox 2 84 Fox 3 67 Fox 4 92 Italy Fox 1 4 43 29 4 Fox 2 5 18 8 4 Luxembourg Fox 5 63 68 75 60 Switzerland Fox 45 60 80 40 Czechoslovakia Fox 1 56 Fox 2 53 Fox 3 79,5 Yugoslavia Fox 1 35 54 75 30 a Determined by tetracycline deposition in bone or teeth (see Table 9) b Presence of antibodies at levels considered indicative of protection 362 Ave. Max. 70 80 51 67 67 72 38 63 75 40 60 65 75 40 77 44 24 15 7 72 80 50 60 50 50 42 60 Vaccinal Remarks strain 3- 5 % of TET - seroconvert, 80-85% of TET + seroconvert 3- 5 % of TET - seroconvert, 80- 85 % of TET + seroconvert 3- 5 % of TET - seroconvert, 80- 85 % of TET + seroconvert SAD B19 Distributed on foot SAD B19 Distributed by air VRG 6/7 seroconvert VRG n = 50 VRG n = 20 SAD SAD SAD B19 Values depend on age, season of sampling and of baiting J . BARRAT & M.F.A. AUBERT TABLE 12 Cost of oral vaccine campaigns, future of these operations Cost/km2 (in ECU) Future of oral Country vaccination Reason Vaccine Baiting Control Germany 15 Continue Austria 14,88 Continue Belgium 15,50 1,70 Continue Denmark Continue Finland 70 on foot, 90 by air• 50 on foot, 12 by ai~ Continue On the border France 14,24 8,49 1,76 Continue Netherlands 15,50 13,00 with control Stop No more rabies Italy Continue Luxembourg 9,5 18,3 Continue Sweden Continue Switzerland 14,5 with control 8,9 Continue Czechoslovakia 500" 20" 1508 Continue Yugoslavia 15,55 Continue • In local currency TABLE 13 Changes in fox densities following oral vaccination campaigns against rabies in foxes Increase of fox Increase is Country density Origin of data considered as Reason serious Germany Yes Field observation No A new level has to be reached Austria Yes Field observation 'Yes Rabies control in the free area Belgium Yes Field observation Yes Echinococcosis Finland No Field observation France Yes Field observation No No scientific evidence Netherlands Yes Field observation No Also observed in rabies free area Italy Yes Field observation Yes Risk of other disease (echinococcosis) Luxembourg Yes Field observation Yes Return of rabies; echinococcosis Switzerland Yes Field observation Yes Return of rabies; echinococcosis; mange Czechoslovakia No Field observation Yugoslavia Yes Field observation No The influence of oral vaccination of foxes on non TABLE 14 Exchange of data on oral vaccination target species is followed by six countries (Table 1 0). Results of oral vaccination campaigns The overall results of oral vaccination of foxes against rabies can be summarized as follows: • After three campaigns in France, 80% of foxes in the vaccination zones have consumed at least one bait and more than 70% have seroconverted. • Among the 13 European countries that have an-swered this question, 12 intend to continue oral vaccination of foxes; the 13th will discontinue the exercise because fox rabies no longer occurs in that country (Table 12). • On the basis of field observations, nine countries indicated that the eradication of rabies or a low-ering in the incidence of the disease will result in an increase in fox numbers (which is also noted in rabies free areas). Five of them consider that this Country Type of exchange Germany Official Austria Unofficial Belgium Official and unofficial Finland Unofficial France Official and unofficial Netherlands Official and unofficial Italy Official Luxembourg Official Sweden Official and unofficial Switzerland Unofficial Czechoslovakia Official Yugoslavia Official may increase the risk of echinococcosis and also pose the problem that a high density of susceptible foxes could result in explosive spread should the infection be re-introduced (Table 13). 363 

Current status of fox rabies in Europe

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Current status of fox rabies in Europe

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