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1.
Four groups of 9 cattle each were vaccinated with 10, 50, 250, or 1,250 micrograms of foot-and-mouth disease (FMD) virus A12 VP1 fusion protein that was produced in Escherichia coli and emulsified in an oil adjuvant. The groups given the 10 and 50 micrograms of antigen were revaccinated at 15 weeks and were challenge exposed at 30 weeks; 5 of 9 and 7 of 9 cattle, respectively, were protected from FMD virus infection. The remaining 2 groups, vaccinated with 250 or 1,250 micrograms of antigen, were revaccinated at 32 weeks and were challenge exposed at 45 weeks; 8 of 9 and 9 of 9 cattle, respectively, were protected. The results indicated that the biosynthetic polypeptide FMD vaccine was effective using vaccination intervals frequently followed with conventional whole-virus vaccines.  相似文献   

2.
Protection of the Swiss national cattle herd against foot-and mouth disease is attempted by annual vaccination with inactivated trivalent (O, A, C) vaccines. With the serotype A5 as an example, this paper demonstrates the procedure of potency testing. Serological data obtained with two vaccines in primovaccinated feeder bulls showed that neutralizing antibodies developed within 7 to 14 days post vaccination. There was no statistically significant difference in the anti-serotype antibody titers induced by each of the vaccines; differences were seen between anti-O serotype and anti-A serotype antibody titers, regardless of which vaccine was used. Epidemiological analyses with about 3000 cattle demonstrated that single-vaccinated, and to a lesser degree twice-vaccinated, animals often had short lived immunity; that is, the antibody titers waned within a few months. In contrast, the majority of thrice and multiple vaccinated animals maintained relatively high antibody titers throughout the twelve month period of observation.  相似文献   

3.
Following an outbreak of FMD caused by an A5 strain in the spring of 1984, ten cattle were vaccinated with samples of the five commercial vaccines used for the vaccination campaign in that year, i.e. two animals per vaccine. Six weeks later the cattle were challenged by contact with animals inoculated with the virus strain isolated from the field outbreak. Seven of the ten cattle became severely ill, exhibiting the typical symptoms of FMD, one animal did not show any clinical symptoms, the remaining two weak ones that might have escaped recognition by the cattlemen. Virus could be recovered from the vaccinated animals from days 2 to 10 following contact with the non-vaccinated infected cattle. It was concluded that a single vaccination does not protect cattle against the isolate.  相似文献   

4.
Six of the seven known serotypes of foot-and-mouth disease (FMD) virus occur in Africa. This paper describes the results of a population-based cross-sectional study of the seroprevalence of FMD and the persistence of the virus in cattle herds and associated sheep flocks in the Adamawa province of Cameroon. Antibody titres measured by the virus neutralising test indicated that serotypes O, A and SAT2 viruses had been circulating in the province. The estimates of apparent seroprevalence in cattle herds, based on five juvenile animals (eight to 24 months old) per herd, were 74.8 per cent for serotype SAT2, 30.8 per cent for serotype A and 11.2 per cent for serotype O, indicating recent exposure; the estimates based on animals more than 24 months of age were 91.1 per cent for SAT2, 83.6 per cent for A and 34.2 per cent for serotype O. Epithelial and oropharyngeal samples were collected from cattle and small ruminants, cultured and typed by ELISA; serotypes A and SAT2 were isolated from both types of sample. The herd-level estimate of apparent prevalence of probang-positive herds was 19.5 per cent and the animal-level estimate of apparent prevalence was 3.4 per cent. The geographical distribution of the seropositive herds based on juveniles suggested that recent SAT2 exposure was widespread and particularly high in the more northern and western parts of the province, whereas recent exposure to serotype A was patchy and more concentrated in the south and east. This distribution corresponded very closely with the distribution of herds from which virus was recovered by probang, indicating recent exposure or infection. No serotype O viruses were recovered from cattle, and the distribution of seropositive herds suggested very localised recent exposure. The apparent prevalence of probang-positive animals declined with the age of the animal and the period since the last recorded outbreak in the herd.  相似文献   

5.
Foot and mouth disease (FMD) is the most contagious disease of mammals and a major threat to animal husbandry sector. In India, vaccination with the inactivated trivalent (O, A and Asia1) vaccine is one proven way for protecting the livestock from FMD. However, many outbreaks have been reported in different parts of the country. Therefore, present study was aimed at elucidating the effects of genetic and non-genetic factors on FMD viral vaccine-elicited immune response in Hardhenu cattle. The effect of season of vaccination was not consistent. The effect of status of animal was significant for all the pre and post AB titres except for pre AB titre of serotype O and post AB titre of Asia1.The estimates of heritability for response to vaccination were low to high ranging from 0.11 to 0.45. The highest heritability estimate was obtained for serotype O and the lowest for Asia1. The heritability estimates for pre and post AB titres ranged from 0.15 to 0.33. All the pre and post AB titres and responses to vaccination had genetic correlations ranged from high negative to high positive among them. Results of this study highlight the variation in vaccine response which needs to be further exploited on large-scale animal data for better immunization and protection against highly contagious viral vesicular disease of cloven-hoofed animals.  相似文献   

6.
In 1999, 10 sporadic outbreaks of cattle foot-and-mouth disease (FMD) occurred in Taiwan. By the time, infection was limited to the Chinese yellow cattle (a native species of beef cattle in Mainland China), which did not develop vesicular lesions under field conditions. Five viruses isolates obtained from individual farms were confirmed to be the serotype O FMD virus (O/Taiwan/1999). During January-February 2000, however, this virus has spread to dairy cattle and goat herds, causing severe mortality in goat kids and vesicular lesions in dairy cattle. Partial nucleotide sequence of the capsid coding gene 1D (VP1) was determined for the virus isolates obtained in this study. Phylogenetic analysis of the VP1 sequences indicated that the O/Taiwan/1999 viruses shared 95-97% similarities to the virus strains isolated from the Middle East and India. The species susceptibility of the O/Taiwan/1999 virus was experimentally studied in several species of susceptible animals, showing that the virus did cause generalized lesions in dairy cattle and pigs, however, it would not cause vesicular lesions on the Chinese yellow cattle and the adult goats. These studies suggested that the O/Taiwan/1999 virus was a novel FMD virus of Taiwan and it presented various levels of susceptibility in cattle species.  相似文献   

7.
Small ruminants play an important role in the epidemiology of Foot-and-Mouth Disease (FMD). Small ruminants are vaccinated with one-half or one-third of cattle dose of oil-based or aqueous vaccines respectively. The extinction antigen payload in vaccine for protection in small ruminants is poorly studied. FMD seronegative Nellore sheep (n=30) and Osmanabadi goats (n=30) were vaccinated with different payloads of O(1) Manisa vaccine (0.45-5 μg). Vaccinated and sero-negative unvaccinated sheep (n=6) and goats (n=6) were challenged intradermally into the coronary band with O(1) Manisa virus. The sheep and goats were monitored for signs of FMD and samples were collected for measuring viraemia and virus associated with nasal swabs and probang samples. Clotted blood was collected for serology. Vaccines containing antigen payload up to 0.94 μg protected sheep and goats against challenge. Sheep and goats vaccinated with 0.45 μg antigen payload were poorly protected against challenge. An antigen payload of 0.94 μg was sufficient to offer complete protection and also absence of carrier status. Sheep and goats with no vaccination or with poor sero conversion to vaccination showed sub-clinical infection and became carriers. The results of the study suggest that vaccination offers protection from clinical disease even at a low payload of 0.94 μg and hence one-half of cattle dose of the oil-based vaccine formulations is sufficient to induce protective immune response in sheep and goats. Since no live virus could be isolated after 5 days post challenge from the nasal swab or probang samples even though viral RNA was detected, the risk of these animals transmitting disease was probably very low.  相似文献   

8.
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9.
The study was conducted in three regional states of Ethiopia: Amhara, Oromia, and Addis Ababa from August 2008 to April 2009 with the objectives of identifying the genetic diversity of serotypes and topotypes in Ethiopia, and determining the attack rate and associations of potential risk factors with foot-and-mouth disease (FMD) seropositivity. A total of 496 cattle were clinically and serologically examined for presence of specific lesions and nonstructural protein for FMD, respectively. Of which, 140 (28.2%) manifested clinical signs and lesions suggestive of FMD, and 219 (44.2%) were seropositive. From a total of 7,781 animals observed and recorded on a designed format in six districts, 1,409 (19.6%) were infected, and 15 (0.12%) died during outbreaks of FMD. Epidemiological investigations revealed that the morbidity rate of the disease was 21.1% in Akaki-kality sub-city, but the mortality rate was <2% in all districts. Furthermore, the mortality and case fatality rates were relatively higher, 1.6% and 8.9% in calves than the other age groups, respectively. From a total of 33 bovine epithelial tissue-cultured samples, 19 (57.6%) showed CPE for FMD virus, in which 16 samples had serotype O and EA-3 topotype, while three samples had found serotype A, Africa topotype, and G-VII strain. Various strains of FMD viruses were isolated in Ethiopia in this study, and therefore, further detailed studies on the evaluation of available vaccines and the development of a vaccine which contains cocktails of antigens of FMD virus strains in the country should be encouraged.  相似文献   

10.
This study was conducted to determine if humoral antibody response of foot-and-mouth disease (FMD) vaccine improved in 8-week-old growing pigs born to well-vaccinated sows pre-treated with 60 mg of poly-γ-glutamic acid (γ-PGA) three days before vaccination. Antibody against FMD virus serotype O was measured 0, 2, 4 and 6 weeks post-vaccination, using a PrioCHECK FMDV type O ELISA kit. The results showed that positive antibody reactions against FMDV serotype O antigen among a component of the vaccine significantly increased in response to pre-injection with γ-PGA.  相似文献   

11.
Outbreaks of foot-and-mouth disease (FMD) from January 1982 through December 2003 were used to examine variations in serotype- and species-specific risk for three control programmes in Colombia:(1982–1983) vaccination, using an aluminium hydroxide, saponin adjuvant, required but not enforced; (1984–1996) vaccination, using an oil double-emulsion adjuvant, required but not enforced; and (1997–2003) enforced vaccination, using an oil double-emulsion adjuvant, restricted animal movement enforced, and slaughter of infected animals. Hypotheses were tested for trend, cyclicity and seasonality in FMD occurrence, and for species- and serotype-specific differences in morbidity and case-fatality. The spatial density of outbreaks was estimated by kernel smoothing. The frequency of outbreaks decreased most between 1984 and 1996 (p < 0.01) for serotype A and between 1997 and 2003 (p < 0.01) for serotype O. Outbreaks occurred in cycles of 3–4 years for both serotypes (p < 0.05). Morbidity was not significantly different in pigs from that in cattle for serotype A-associated outbreaks (p = 0.314), but was higher in pigs than in cattle (p = 0.019) for serotype O-associated outbreaks. For both serotypes, case-fatality was higher for pigs than for cattle (p < 0.009). Temporal variation in FMD incidence provided insight into the expected evolution of FMD control for countries with similar conditions and where FMD is endemic.  相似文献   

12.
The epidemiological analysis of the cattle population during the eradication plan of foot and mouth disease (FMD) in Argentina clearly indicated a higher incidence of the disease in animals within their first year of age. It is important to improve the efficacy of the vaccination in those animals. In a previous report, we have shown the effect of an immunomodulator, Avridine (Avr), in the enhancement of the immune response elicited by FMD virus (FMDV) vaccines in experimental hosts [Berinstein, A., Pérez Filgueira, M., Schudel, A., Zamorano, P., Borca, M., Sadir, A.M., 1993. Avridine and LPS from Brucella ovis: effect on the memory induced by foot-and-mouth disease virus vaccination in mice. Vaccine 11, 1295-1301]. In this report, we analyze the effect of Avr in the improvement of the anti-FMDV immune response elicited in young animals immunized with a tetravalent vaccine. The anti-FMDV antibody response was evaluated using a liquid-phase blocking sandwich ELISA (LPBE) [Smitsaart, E.N., Zanelli, M., Rivera, I., Fondevila, N., Compaired, D., Maradei, E., Bianchi, T., O'Donnell, V., Schudel, A.A., 1998. Assessment using ELISA of the herd immunity levels induced in cattle by foot and mouth disease oil vaccines. Prev. Vet. Med 33, 283-296] while the cellular response was detected using an antigen specific lymphoproliferative test [Zamorano, P., Wigdorovitz, A., Chaher, M., Fernández, F., Sadir, A., Borca, M., 1994. Localization of B and T cell epitopes on a synthetic peptide containing the major immunogenic site of FMDV O1 Campos. Virology 201, 383-387]. The results show that, while no differences were detected in the cellular response, the anti-FMDV antibody reaction was significantly (<0.05) higher in animals immunized with the immunogen containing Avr. At 90 days post vaccination, 89-100% of the animals immunized with Avr presented predicted protection (PP) higher than 82% while just 50-61% of the animals immunized with vaccine without immunomodulator presented that characteristic. Also, it is shown that the increase in the anti-FMDV antibody titre in animals immunized with the vaccine containing Avr was mediated by an increase in the levels of both IgG1 and IgG2 which presented a significative correlation with LPELISA antibodies titres. It is concluded that the addition of Avr in the FMDV vaccines improve the immune status of the calves, the cattle population that suffers the highest epidemiological risk.  相似文献   

13.
Vaccination with inactivated vaccine is an important measure to prevent and control foot-and-mouth disease (FMD), however, the immune effect and antigenic purity of inactivated vaccines are two major concerns for the establishment and evaluation of FMD free zones with vaccination. In this study, four groups of FMD type O and type A bivalent inactivated vaccines from 3 FMD vaccine manufacturers (designated as A, B and C) were selected to inoculate healthy juvenile cattle of FMD free. All cattle were immunized 3 or 4 times at a 1-month interval. Serum samples were collected before and after 1 month of every vaccination to determine the level of antibody to structural protein and non-structural protein. Results：(1) The qualified rates of antibody to structural protein: in group a1 (vaccine from company A, different batches), the antibody qualified rate could reach 100% for type O and type A, respectively after each vaccination. In group a2 (vaccines from company A, same batch), the antibody qualified rates were 36.7%, 98.3% and 100% for type O, and 15%, 86.7% and 100% for type A after the first to the third vaccination, respectively. In group b (vaccine from company B, same batch), the antibody qualified rates were 18.3%, 97% and 100% for type O, and 1.7%, 45% and 53.3% for type A after the first to the third vaccination, respectively. In group c (vaccines from company C, same batch), the antibody qualified rates were 26.7%, 96.7% and 100% for type O, and 21.7%, 71.7% and 100% for type A after the first to the third vaccination, respectively. (2) Antibody positive rate to non-structural protein 3ABC (confirmed with second ELISA test): In group a1, the positive rates were 0.7%, 1.4%, 9.5% and 4.8% after the first to the fourth vaccination, respectively; In group a2 and c, no 3ABC antibody-positive animal was detected after 3 repeated vaccination; In Group b, only one animal with a positive rate of 0.6% was detected after the third vaccination. The antibody qualified rates to the structural protein of FMDV in 3 of the 4 groups were far less than 70% after the primary vaccination, however, those were increased significantly after boost and repeated vaccination. The antigen purity of vaccines in three groups (a2, b and c) can meet the requirement of OIE standard on the FMD vaccine, however, the seroconversion to 3ABC antibody was obvious in animals from group a1 after repeated vaccination, which would cause some extent of interference to differential diagnosis. Also, a combination of a primary screening test and a confirmatory ELISA test can further improve the accuracy of differential diagnosis. This study provides an important scientific basis to make a rational program for establishment and evaluation of FMD free zone with vaccination.  相似文献   

14.
灭活疫苗免疫是防控口蹄疫的重要措施,但是灭活疫苗的免疫效果及其对感染与免疫鉴别诊断的干扰一直是口蹄疫免疫无疫区建设评估需要明确的重要问题。本研究中选择了3个企业（代号A、B与C）的4组口蹄疫O型与A型二价灭活疫苗,分别免疫口蹄疫抗体阴性健康未成年牛,免疫3～4次,测定免疫前后结构蛋白和非结构蛋白抗体的应答水平。结果显示：（1）结构蛋白抗体合格率：a1组（A企业多批次疫苗）4次免疫后O型和A型均为100%;a2组（A企业同批次疫苗）一~三免O型为36.7%、98.3%与100%,A型为15%、86.7%与100%;b组（B企业疫苗）一~三免O型为18.3%、97%与100%,A型为1.7%、45%与53.3%;c组（C企业疫苗）一~三免O型为26.7%、96.7%与100%,A型为21.7%、71.7%与100%。（2）非结构蛋白3ABC抗体阳性率（两种方法复核结果）：a1组一~四免分别为0.7%、1.4%、9.5%与4.8%;a2组和c组三次免疫均未检测到阳性;b组仅三免后阳性率为0.6%。3组灭活疫苗首次免疫牛的抗体合格率远不及70%,但加强免疫后抗体合格率均显著提高;非结构蛋白抗体检测结果表明有3组疫苗的抗原纯净度符合OIE的要求,但a1组灭活疫苗免疫后,仍然对感染与免疫鉴别诊断存在干扰;采用两种非结构蛋白抗体检测方法进行复核检验,可以提高感染与免疫鉴别诊断的准确性。本研究为口蹄疫免疫无疫评价方案的制定提供了科学依据。  相似文献   

15.
Young calves were vaccinated with Belgian foot-and-mouth disease (FMD) vaccine and revaccinated with either the same vaccine or with a foreign FMD vaccine.There was a significant serological response to the primary vaccine strains after the first vaccination which was greater following revaccination. At one and two months after revaccination there was no significant difference between the responses to revaccination with vaccine identical to the primary vaccine or with the foreign FMD vaccine.It was concluded that revaccination of young calves is effective even with an FMD vaccine different from the primary vaccine.  相似文献   

16.
In northern Pakistan, many farming communities rely on domestic yak (Bos grunniens) as a principle source of income. A 2006 participatory disease surveillance report from this region indicated that foot-and-mouth disease (FMD) is the most prevalent annual disease of yak. Our objectives of this study were to determine exposure levels of yak to FMD virus; implement a vaccination program based on current, regional FMD virus serotypes and subtypes; and quantify immune responses following vaccination. Blood samples were used to determine pre-vaccination exposure of animals to FMD virus by antibody presence to non-structural proteins of FMD virus using a 3-ABC trapping indirect ELISA. Vaccine used consisted of FMD serotypes ‘O’ (PanAsia-2), ‘A’ (Iran-05), and ‘Asia-1’ (Shamir), but changed later during the study to match newly circulating viruses in the country (‘O’-PanAsia-2; ‘A’-Turk-06 and Asia-1-Sindh-08). Three hundred sixty-three blood samples were tested from selected villages to determine pre-vaccination FMD virus exposure in yak with an average of 37.7%. Immune responses from initial vaccination and booster dose 30 days later showed clear protective levels (as mean percent inhibition) of antibodies against structural proteins of serotypes ‘O,’ ‘A,’ and ‘Asia-1.’ These responses remained above threshold positive level even at day 210 following initial vaccination. Results of sero-surveillance and anecdotal information of repeated FMD outbreaks demonstrate the persistence of FMD virus of yak in northern Pakistan. Laboratory results and field observations clearly indicated that yak can be protected against FMD with a good quality vaccine with FMD serotype(s) matching current, regionally circulating FMD virus.  相似文献   

17.
There has been an increasing interest in finding new formulations that qualify as vaccine adjuvants, which must be safe, stable, and have the capacity to stimulate a strong immune response. In this study, a basic formulation of a water-in-oil-in-water (W/O/W) adjuvant CV13 was developed, and ginseng stem-leaf saponins (GSLS) were added as an immune booster into oil phase. The physicochemical properties of the adjuvant were tested. Furthermore, the immune activity and the adjuvant effects, as indicated by the foot-and-mouth disease virus (FMDV) antigen were evaluated. The results showed that CV13 was similar in appearance to ISA 206 and could package FMDV antigen into a stable W/O/W emulsion. The FMD vaccine prepared with CV13 alone or CV13 containing GSLS achieved pharmaceutical characteristics comparable to a vaccine prepared with ISA 206, moreover the structural stability of the CV 13 vaccine was found to be better. Mice that were immunized with the FMD vaccine prepared with CV13 containing GSLS presented a significantly higher LPBE antibody titer and splenocyte proliferation rate than those immunized with a vaccine prepared with CV13 alone (p < 0.05). In addition, there was no significant difference between the groups that were immunized with FMD vaccine prepared with CV13 containing GSLS and ISA206 in terms of cellular and humoral immune response. In this paper, CV13 containing GSLS shows excellent immunologic adjuvant effect in mice model, and this new adjuvant may provide a potential choice for FMD vaccine production in the future.  相似文献   

18.
Foot-and-mouth disease (FMD) is an economically important disease of cloven-hoofed animals that is primarily controlled by vaccination of susceptible animals and movement restrictions for animals and animal-derived products in South Africa. Vaccination using aluminium hydroxide gel-saponin (AS) adjuvanted vaccines containing the South African Territories (SAT) serotypes has been shown to be effective both in ensuring that disease does not spread from the endemic to the free zone and in controlling outbreaks in the free zone. Various vaccine formulations containing antigens derived from the SAT serotypes were tested in cattle that were challenged 1 year later. Both the AS and ISA 206B vaccines adjuvanted with saponin protected cattle against virulent virus challenge. The oil-based ISA 206B-adjuvanted vaccine with and without stimulators was evaluated in a field trial and both elicited antibody responses that lasted for 1 year. Furthermore, the ISA 206 adjuvanted FMD vaccine protected groups of cattle against homologous virus challenge at very low payloads, while pigs vaccinated with an emergency ISA 206B-based FMD vaccine containing the SAT 1 vaccine strains were protected against the heterologous SAT 1 outbreak strain.  相似文献   

19.
The aim of this study was to evaluate the value of commercially available kits for the detection of foot-and-mouth disease (FMD) virus infection in vaccinated cattle. The cattle were vaccinated with a commercial aqueous FMD vaccine type A24 and subsequently challenged 28 days post vaccination with homologous FMD virus. Seven of eight animals were protected from clinical disease and all became carriers. They were bled sequentially for up to 130 days post infection and samples of sera were tested with three ELISA kits: CHEKIT FMD-3ABC, Ceditest FMDV-NS and SVANOIR FMDV 3ABC-Ab ELISA. The Ceditest kit appears to be relatively higher sensitive than the others. When examined with this ELISA, all cattle developed of FMDV nonstructural proteins (NSPs) antibodies and remained positive throughout the period of the experiment. The response of antibodies against 3ABC antigen delayed in two cattle challenged with FMDV A24 virus. One of the cattle reacted negatively in Svanoir ELISA kit and sera from two animals were found negative in CHEKIT ELISA. It can be concluded that all tested kits can be a promising tool for FMD control and eradication campaigns in situation where emergency vaccination was applied.  相似文献   

20.
In this study, we investigated whether Cedivac-FMD, an emergency vaccine against foot-and-mouth disease (FMD), is suitable for use conjointly with a screening program intended to confirm freedom from disease in vaccinated herds based on evidence of virus replication in vaccinates. Different sets of sera were tested using the Ceditest FMDV-NS ELISA for the detection of antibodies against non-structural proteins (NSPs) of FMD virus. During a vaccine safety study, serum samples were collected from 10 calves, 10 lambs and 10 piglets following administration of a double dose and a repeat dose of high payload trivalent Cedivac-FMD vaccine. All serum samples collected both 2 weeks following the administration of a double dose as well as those collected 2 weeks after the single dose booster (given 2 weeks after the double dose) were negative in the Ceditest FMDV-NS ELISA. In a series of vaccine potency experiments, serum samples were collected from 70 vaccinated cattle prior to and following exposure to infectious, homologous FMD virus. When testing cattle sera collected 4 weeks after vaccination with a regular dose of monovalent >6 PD(50) vaccines, 1 of 70 animals tested positive in the NSP antibody ELISA. After infection with FMD virus, antibodies to NSP were detected in 59 of 70 vaccinated cattle and 27 of 28 non-vaccinated control animals within 7 days. Cedivac-FMD vaccines do not induce NSP antibodies in cattle, pigs or sheep following administration of a double dose or a repeat dose. FMD-exposed animals can be detected in a vaccinated group within 7-14 days. Because Cedivac-FMD does not induce NSP antibodies, the principle of 'marker vaccine' applies.  相似文献   

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