The foot and mouth disease situation in Iran in

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1 Rev. sci. tech. Off. int. Epiz., 1985, 4 (2), The foot and mouth disease situation in Iran in M.R. FIROUZI-BANDPAY*, M. AMIGHI*, R. PIROIRD**, M. LOMBARD**, H. FAVRE** and M. SALEHIZADEH* Summary : During the period 1980 to 1982 only the O1 enzootic type of foot and mouth disease virus (FMDV) was frequently isolated from the suspected samples received at the Razi Institute, collected from different provinces of the country. In the first half of 1983 FMDV type A was isolated from a sample received from a cattle farm in the south western part of the country (Fars) and a few days later the Asia 1 type was isolated and identified in the western part (Lorestan), being the first reappearance of this type since In the serological survey of the different strains of FMDV isolated in Iran, it was determined that the O type isolated in 1982 was to some extent different to the O Tabriz No difference was observed between the Asia 1 types isolated in 1973 and There was however, a great difference between type A 1983 and A22, the endemic type of Iran. KEY-WORDS: Aphthovirus - Cattle diseases - Diagnosis - Epidemiological surveys - Foot and mouth disease - Iran - Serological techniques - Serotypes. INTRODUCTION AND HISTORY A brief historical background of foot and mouth disease virus (FMDV) types isolated and identified in the Razi Institute is explained as follows : The O type was isolated in 1955 and the A type in The SAT 1 type appeared in 1962 and the latest case was reported in In 1964 the A22 subtype of FMDV was isolated in Iran and, since 1964, the A22 and O1 subtypes of FMDV were frequently isolated and identified in different regions of the country. Since 1973 the A22 type has been isolated at intervals and the severity of the FMD caused by A22 has decreased annually, as seen from 21 March 1973 to 21 March 1974 when 38 samples were identified as type A whereas, since 21 March 1974, only 17 cases of type A have been isolated from a total number of about samples received at the FMD laboratory. It should be mentioned that there were no cases of A type in 1976, 1980, 1981 or The presence of Asia 1 type in Iran was not reported until late in 1957 and, subsequently, in These cases were not very severe and were successfully controlled in a very short period of time. In 1973 Asia 1 type entered Iran from the eastern * Institut Razi, Kesha 23, Hessarak-Karadj, Iran. ** Rhône-Mérieux, Laboratoire IFFA, 254, rue Marcel Mérieux, Lyon Cedex 07, France.

2 312 borders ; it was very severe and caused heavy losses. This outbreak was also controlled by mass vaccination, together with the enforcement of animal health measures, in a period of less than four months. The latest outbreak of Asia 1 type occurred in SEROLOGICAL STUDY Typification of FMD samples The FMD samples from infected animals, collected in different regions of the country, were tested by complement fixation according to Kolmer's method (100 % haemolysis). In this report, the different types of FMDV isolated during the period 21 March 1980 to 21 March 1984 are shown in the various tables. As Table III indicates, the enzootic type of Iran (O1) has been isolated from almost all provinces of the country; 352 (24.91 %) samples were identified as type O from the total number of samples tested during the period mentioned. Tables I and III show that, 3 years after the disappearance of type A, the first case was isolated from a sample collected in Fars in June 1983 and subsequently 2 suspected cases on 19 January 1984 from Western Azerbayjan. The disease was controlled by applying quick sanitary measures together with mass vaccination and rigid prevention of the movement of diseased animals to other regions. It is also demonstrated in the various tables that, in June 1983, a case of Asia 1 type was isolated and identified in a sample received from Lorestan, which was the TABLE I Isolation and identification of FMDV from samples received from 21 March 1980 to 21 March 1984 Year Type Virus O Virus O Virus O Virus Month Total Pos Neg Total Pos Neg Total Pos Neg Total O + Asia 1 + March-April _ 10 April-May May-June June-July July-Aug Aug.-Sept Sept.-Oct Oct.-Nov Nov.-Dec Dec.-Jan Jan.-Feb Feb.-March Total A Neg

3 TABLE II Epizootiology of FMD during the period of 21 March 1980 to 21 March 1984 Year Type Total O % % % A 22 Asia 1 Neg. O A 22 Asia 1 Neg Total TABLE III Isolation and identification of FMDV types from different provinces of Iran from 21 March 1980 to 21 March 1984 Province Total O Asia 1 Neg. 1. Central Fars Gergan Khorassan Western Azerbayjan Mazandaran Isfahan Semnan Lorestan Guilan Ham Khuzestan Eastern Azerbayjan Zanjan Kerman Bakhtaran Hamadan Sistan and Bluchestan Kordestan Yazd Chahar Mahal Bakhtiari Beechehr 3 3 Total first case to reappear since The disease spread to some extent to the other provinces and, with the exception of a few cases in sheep, the disease was mainly observed in cattle and it is thought that sheep were probably the carrier of this type. It should be mentioned that the recent outbreak of Asia 1 type was less severe than that of The reasons might be given as follows: 1. According to the results of the serological study achieved for subtype identifi-

4 - 314 cation, which are given hereafter, the Asia 1 type isolated in 1983 was closely related to that isolated in Most of the industrial cattle farms were resistant against the disease, due to the regular vaccination that has been carried out during the last 10 years. 3. Upon identification of the first foci, extreme effort was made to revaccinate all the susceptible animals with trivalent vaccine (A 2 2, O and Asia 1). 4. In some of the dairy cattle farms, the infection was mostly observed among the young calves and it was realised that they did not receive a sufficient dose of the vaccine or the booster was not administered. IDENTIFICATION OF SUBTYPES A serological study was carried out to compare the A type and Asia 1 type isolated in 1983 with A 2 2, the endemic type of Iran, and Asia 1 type isolated in Some of the O strains of FMDV isolated during recent years in Iran and various countries of the Middle and Near East were also analysed to determine their serological properties by the complement fixation test (50 % haemolysis) in cooperation with our colleagues from the Rhône-Mérieux Institute of France. The results concerning the r 1 values obtained, are demonstrated in Tables IV and V. = Activity of serum against heterologous strain Activity of serum against homologous strain TABLE IV Comparison of r correlations between different FMD virus isolates of Asia 1 and A 2 2 types from Iran Virus Asia 1 Asia 1 Serum Asia Virus A 22 A 2 2 Iran Serum Azerb A : Azerb Tables IV and V indicate that : 1. The Asia 1 type isolated in 1973 and 1983 are closely related (r 1 = 0.71). 2. The A 2 2 type 1983 is widely different from A 2 2 Azerb (r 1 = 0.2). 3. Eastern O strains are different to European O strains (0.3 < r 1 < 0.57), and are thus very homogeneous. 4. Eastern O strains remain relatively near to Turkish vaccine strain (O Manisa) and Egyptian strain (O Sharquia) as the ratio is between 0.66 and Iranian strain (O Tafreche) seems to be, to some extent, different from the O Tabriz (r 1 = 0.56).

5 315 TABLE V Comparison of r correlations between different field and reference FMD virus isolates in Iran Virus 0 O O O O 0 O Sanabel Kafr Azerbayjan Khorassan Israel Diarb Tafreche Sera Arabia Egypt Iran Iran Egypt Iran O1 Lausanne O1 BFS 18/ Manisa* Sharquia* Machoury* 1968 NT Tabriz* 1977 NT NT NT NT Israel * O Manisa Turkey 1969, O Sharquia Egypt 1972, O Machoury Iran 1968, O Tabriz Iran All these sera are representative of vaccine strains used in the past or at present. CONCLUSION The epidemiological survey of FMD in Iran during the four years indicates a low variation in O type which has been enzootic in the country for a long time. The A type, also enzootic in Iran, appears to derive from the A22 strain first recognised in In spite of low serological values against this historical strain, the recent strains belong to the A22 subtype as indicated by the epidemiological data and by the effective protection of vaccine prepared with the A virus in the Razi Institute (3). The Asia 1 type which reappeared in 1983, after ten years of absence, is serologically very near the historical strain of These data are checked by the effective protection conferred by the vaccine in the field. * * * LA SITUATION DE LA FIÈVRE APHTEUSE EN IRAN DE 1980 A M.R. Firouzi-Bandpay, M. Amighi, R. Piroird, M. Lombard, H. Favre et M. Salehizadeh. Résumé : Durant la période de 1980 à 1982, seul le type enzootique O1 du virus de la fièvre aphteuse a été fréquemment isolé des échantillons de virus aphteux suspects, reçus à l'institut Razi et collectés dans différentes provinces du pays. Durant le premier semestre 1983 le virus de la fièvre aphteuse de type A a été isolé d'un échantillon provenant d'une ferme d'élevage dans la partie sud-ouest du pays (Fars) et, quelques jours plus tard, le type Asia 1 a été isolé et identifié dans la partie ouest (Lorestan), ce qui était la première réapparition de ce type depuis Dans l'étude sérologique des différentes souches de virus aphteux isolées en Iran, il a été déterminé que le type O isolé en 1982 était, dans une certaine mesure, différent de la souche vaccinale O Tabriz Aucune différence n'a été observée entre la souche Asia 1 isolée en 1983 et celle de 1973

6 (souche vaccinale). Il y a une grande différence dans le type A entre le virus de 1983 et le A22 de 1964, sous-type jusque là endémique en Iran. MOTS-CLÉS : Aphthovirus - Diagnostic - Enquêtes épidémiologiques - Fièvre aphteuse - Iran - Maladies des bovins - Sérotypes - Techniques sérologiques. * * * SITUACIÓN DE LA FIEBRE AFTOSA EN IRÁN DE 1980 A M.R. Firouzi-Bandpay, M. Amighi, R. Piroird, M. Lombard, H. Favre y M. Salehizadeh. Resumen : Durante el período de 1980 a 1982, únicamente se aisló frecuentemente el tipo enzoótico O1 del virus de la fiebre aftosa en las muestras de virus sospechosos, recibidos en el Instituto Razi y recogidos en distintas provincias del país. Durante el primer semestre de 1983, se aisló el virus de la fiebre aftosa de tipo A en une muestra procedente de una granja en la parte suroccidental del país (Fars) y algunos días más tarde, se aisló e identificó el tipo Asia 1 en la parte occidental (Lorestan), lo que constituía la primera reaparición de este tipo desde En el estudio serológico de las distintas cepas del virus aftoso aisladas en Irán, se determinó que el tipo O aislado en 1982 era, en cierto modo, distinto de la cepa vacunal O Tabriz No se observó ninguna diferencia entre la cepa Asia 1 aislada en 1983, y la de 1973 (cepa vacunal). Existe gran diferencia en el tipo A entre los virus de 1983 y el A22 de 1964, subtipo hasta entonces endémico en Irán. PALABRAS CLAVE : Aftovirus - Diagnóstico - Encuestas epidemiológicas - Enfermedades de los bovinos - Fiebre aftosa - Irán - Serotipos - Técnicas serológicas. * * * REFERENCES 1. AMIGHI M. & MASTAN M.B. (1970). Importance et intérêt de l'étude des facteurs jouant un rôle dans l'épizootie de la fièvre aphteuse au Moyen-Orient. Commission européenne de lutte contre la fièvre aphteuse, Ankara (Turquie). Compte rendu de la réunion tenue du 8 au 26 septembre AMIGHI M., MASTAN M.B., FIROUZI-BANDPAY M.R., LOMBARD M., PERRENOT F. & FAVRE H. (1978). Résultats actuels d'une étude sérologique de quelques virus de type O apparus au Moyen-Orient et en Europe. Bull. Off. int. Epiz., 89 (11-12), ARROWSMITH A.E.M. (1975). Variation among strains of type A FMDV in the Eastern Mediterranean region J. Hyg. Camb., 75, FIROUZI-BANDPAY M.R. (1976). The situation of foot and mouth disease in Iran in R.C.D. Seminar on Animal Health, December 1976, Tehran.

7 FIROUZI-BANDPAY M.R., AMIGHI M., MASTAN M.B. & MALEKNEJAD P. (1974). The outbreak of foot and mouth disease (Asia 1 type) in 1973 in Iran. Bull. Off. int. Epiz., 81 (7-8), KOLMER J.A. (1928). Serum diagnosis by complement fixation test. Lea and Febiger Publishers, Philadelphia, MASTAN M.B. et al. (1975). Etude de différentes souches de virus Asia 1 réalisée à l'institut Razi, d'une part des souches isolées en 1964 et 1973 en Iran, d'autre part d'une souche isolée en 1974 en Iraq. Bull. Off. int. Epiz., 83 (1-2), OSLER A.G., STRAUSS J.H. & MAYER M.M. (1952). Off. J. Am. Vener. Dis. Ass., 36 (1),