Takashi OGAWA, Masashi ISHIKAWA*, and Tadahiro INOUE*
Abstract
Trends of epidemics of bovine infectious diseases in Japan were investigated using the incidence rates recordes during the period 1987-1993. For example, infectious bovine rhinotracheitis among the virus diseases predominated in spite of extensive control of vaccination. Outbreaks of corona or bovine RS virus infection were wide spread in beef cattle colonies. In the case of bacterial diseases, Johne's disease has recently prevailed nationwide despite the extensive measures of control implements. Salmonellosis has also spread to adult and growing cattle. These diseases are associated with intensive livestock production and still remain major problems (especially bronchopneumonia, diarrhea and gastroenteritis) for livestock in Japan. On the other hand, the incidence of theileriosis among the parasitic diseases has decreased due to the implementation of effective tick-eradication programs.
Introduction
Many infectious diseases were either effectively controlled or eradicated from the latter part of the 19th century and the middle of the 20th century in developed countries using new techniques developed during the microbial revolution and older methods, including quarantine, importation restrictions, slaughter and hygiene 6). Massive epidemics of bovine infectious diseases still pose problems in South Asia, Africa and South America. For example, foot and mouth disease (FMD) or rinderpest has remained a major disease in the countries of the above regions. In contrast, after the eradication of both diseases in Japan, disease free conditions were maintained due to effective control of animal quarantine systems and the fact that Japan is an island. However, some infectious diseases, for example brucellosis and tuberculosis, have persisted at low levels, despite the application of various measures to control. Infectious bovine rhinotracheitis (IBR) and Johne's disease have allowed an increase in morbidity and economic loss. These diseases which are associated with intensive livestock production may currently be essentially the major diseases posing problems in Japan. Therefore, it is important to improve the database on animal disease outbreaks at the national level to identify problems. The purpose of this paper is to summarize the incidence rates of bovine infectious diseases and to describe the trends of epidemics of important diseases.
Materials and methods
1) Epidemiological data of bovine infectious diseases
Morbidity data of designated and notified bovine infectious diseases based on the Domestic Animal Infectious Disease Control Law (No.166 of 1951) in Japan were summarized from the official reports on outbreaks published in the statistics on animal hygiene from 1987 to 1993. The other morbidity data except for the above diseases were collected from monthly reports of animal health information in the animal health weekly 1) ; the diagnoses were all carried by the diagnosis laboratory of animal hygiene service center (AHSC) in each Prefecture of Japan.
2) Animal disease names
The names of bovine infectious disease were arranged based on the nomenclature of animal diseases in Japan (draft) edited by Hatakeyama and Ogawa (1992) according to the International Classification of Diseases (ICD) published by the World Health Organization (WHO) and Food and Agriculture Organization (FAO).
3) Epidemiological index
Incidence of bovine infectious diseases was expressed as the number of new cases that occurred in the dairy and beef cattle populations at risk each year from 1987 to 1993 in Japan by using the above data of morbidity. The incidence rate per one million head of dairy and beef cattle populations at risk was calculated as follows:
Incidence (number of new cases)
Incidence rate = --------------------------------- x 1,000,000
Cattle population at risk
The data of the cattle population used in the above denominator were obtained from annual statistics of livestock , dated 1 February in each year from 1987 to 1993 that was provided by the statistics and Information Department, Ministry of Agriculture, Forestry and Fisheries of Japan
.
Table 1. Trends of Epidemics of Bovine Infectious Disease in Japan dudring 1987-1993 (per one million of cattle population)
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Year
Pathogen Disease name 1987 1988 1989 1990 1991 1992 1993
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DNA virus Bovine papular stomatitis - - 3.8 - - 1.0 -
Pseudo cowpox 5.1 1.9 - - - - -
Malignant catarrhal fever - 0.6 0.9 0.6 0.2 0.2 -
Aujeszky's disease - - - - 0.4 - -
Infectious bovine rhinotracheitis-b) 133.8 126.0 79.7 39.3 75.7 143.6 53.1
Bovine adenovirus infection 1.5 21.4 0.9 1.3 0.4 1.0 0.2
Bovine papillomatosis - 0.6 - - - - -
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RNA virus Ibaraki disease-a) 57.3 0.2 - - - - -
Reovirus infection 4.7 - - - - - -
Bovine rotavirus infection 19.2 23.1 14.3 45.6 86.2 33.9 15.3
Chuzan disease 0.2 - - - - - -
Bovine viral diarrhea mucosal disease 25.4 15.2 4.1 9.0 11.5 3.6 2.2
Bovine coronavirus infection 79.7 293.1 198.0 206.1 199.7 49.6 67.5
Parainfluenza 16.5 - 19.4 12.8 0.8 - 10.4
Bovine RS virus infection 31.7 48.2 26.3 85.5 36.1 51.2 40.6
Bovine ephemeral fever-a) - 79.7 71.4 - 1.2 - -
Akabane disease 2.3 10.5 1.9 2.1 4.3 1.0 1.2
Ainovirus infection - - - 0.2 0.6 - -
Bovine leucosis 14.7 13.5 13.0 15.5 9.2 42.2 43.6
Bovine rhinovirus infection 0.4 0.2 4.3 - - - -
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Rickettsia Anaplasmosis-a) - - 1.5 0.4 0.4 - -
Eperythrozoonosis 0.2 - - - - - -
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Mycoplasma Mycoplasma infection 6.8 6.2 10.7 1.3 5.3 17.5 -
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Spirochaeta Leptospirosis - 1.5 - - - - -
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Spirillum Genital campylobacteriosis 0.2 - - 0.4 - - -
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Gram-negative Bovine infectious keratoconjunctivitis 33.2 21.9 39.1 20.6 3.9 75.9 44.
aerobic bacillus Brucellosis-a) - - 0.2 0.2 0.2 0.2 -
Pseudomonas infection 0.2 0.2 - - 0.2 - 0.2
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Year
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Pathogen Disease name 1987 1988 1989 1990 1991 1992 1993
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Gram-negative Colibacillosis 59.7 53.1 98.0 45.2 38.4 40.6 33.
0facultative Salmonellosis 93.7 70.3 119.8 63.9 114.1 150.2 105.5
anaerobic Pasteurellosis 131.2 118.7 78.8 89.7 89.9 153.2 127.6
bacillus Actinobacillosis 0.4 - - - - 0.2 -
Haemophilus somnus infection 58.0 28.9 15.2 13.2 16.8 10.0 11.3
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Gram-negative Fusobacterium infection 0.6 0.9 0.8 0.8 - 0.2 0.2
non-spore bacillus
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Gram-positive Staphylococcosis 1.2 - 1.5 - - 0.2 -
coccus Streptococcal infection 1.2 2.6 0.6 1.1 0.8 2.0 -
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Gram-positive Anthrax-a) 0.2 0.2 - - 0.2 - -
spore-former Enterotoxemias 19.0 4.1 8.3 13.0 27.1 11.2 8.
0anaerobic Blackleg* 9.4 2.4 1.5 4.4 4.1 2.4 1.4
bacillus Malignant edema 2.6 2.8 2.8 2.9 1.2 1.8 5.6
Clostridial infection 3.2 12.9 10.5 4.0 4.9 5.0 10.6
Tetanus-b) 6.8 7.3 7.9 8.0 6.2 7.8 7.2
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Gram-positive Listeriosis 1.1 - - 0.8 0.4 0.2 1.6
non-spore Bovine cystis and pyelonephritis 1.3 - 0.4 1.3 - - -
bacillus Actinomycosis 0.4 0.4 0.2 0.8 0.4 0.6 -
Dermatophilosis - - - - 54.2 0.8 -
Actinomyces pyogenes infection 11.9 1.5 7.7 1.5 1.4 3.6 -
Tuberculosis-a) 20.0 9.2 7.7 6.9 7.2 2.8 1.2
Johne's disease-a) 34.5 29.8 28.7 38.7 43.5 43.4 45.0
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Fungi Fungal infection 24.3 3.0 6.4 - 9.2 12.2 46.0
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Protozoa Coccidiosis 36.9 48.6 44.2 44.5 67.5 73.7 51.6
Cryptosporidiosis 1.7 - 0.2 0.4 4.5 - 0.2
Neosporosis - - - - - 0.6 -
Piroplasmosis-a),c) 18.3 14.1 16.7 18.5 18.9 11.2 0.2
Piroplasmosis-d) 111.0 75.4 70.7 132.1 40.4 17.3 9.2
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Year
Pathogen Disease name 1987 1988 1989 1990 1991 1992 1993
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Nematoda Mecistocirrus infection - 0.2 - 0.4 - - -
Bunostomum infection - - - 0.6 - - -
Strongyloides infection 30.9 10.7 24.1 38.2 37.8 1.8 9.6
Oesophagostomum infection 0.2 - - - - - -
Trichuris infection 0.2 0.9 - 0.2 0.4 - -
Dictyocauliasis 0.2 0.9 - 0.2 0.4 - -
Thelaziasis 16.8 . - - - - -
Ascariasis - 0.2 - 0.4 - 0.4 0.2
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Cestodia Cestodiasis 1.7 - 0.2 - 6.2 0.2 -
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Trematodia Fascioliasis 7.3 16.5 9.0 5.0 4.3 1.0 11.3
Paramphistomiasis 1.7 0.2 - - - 0.2 -
Eurytremiasis 0.2 - - - - . -
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Arthlopod Scabies 2.6 9.0 1.5 1.9 - 3.0 0.8
parasitism Lousiness 2.1 - 1.2 - - - -
Warble infestation-b) 3.0 1.5 8.8 3.4 - - -
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- : No outbreaks.
a) : Designated infectious diseases based on the Domestic Animal Infectious Disease Control Law (Law No.166,1951).
b) : Notified infectious diseases based on the same Law as above.
c) : Designated babesiosis and theileriosis.
d) : Excluding designated babesiosis and theileriosis above..