E Smitsaart

Instituto Nacional de Tecnología Agropecuaria, Buenos Aires, Buenos Aires F.D., Argentina

Are you E Smitsaart?

Claim your profile

Publications (19)44.38 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Foot-and-Mouth Disease Virus serotype O has been circulating regularly throughout most provinces of Ecuador, one of the two South American countries that still remain endemic, although satisfactory vaccination coverage was reported. This study concentrates in the characterization of isolates collected during 2008-2011, focusing particularly on the antigenic and immunogenic relationships of the field viruses with the O1/Campos vaccine strain in use in the region and with an experimental vaccine formulated with a representative strain of the 2010 epidemic. The results established that antigenically divergent variants poorly protected by the vaccine in use emerged and co-circulated in a limited period of time. A monovalent vaccine formulated with the representative 2010 strain elicited high antibody titers and protected against challenge with homologous virus. In addition, cross-reactive antibodies to predominant viruses in the region were established. In overall this study indicates the ability of the virus to diversify under field conditions in which a vaccine strain with poor match is applied, and the potential of the selected 2010 field virus as a vaccine candidate for incorporation into strategic antigen banks and/or for addition to current formulations for systematic vaccination, in order to prevent the emergence of even more divergent isolates in the future.
    Vaccine 03/2014; · 3.77 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Foot and mouth disease is an acute disease of cattle with a broad distribution around the world. Due to the fast spread of FMDV infections, control measures must be applied immediately after an outbreak, such as the use of vaccines that induce fast protection. Previously, it was shown that mice vaccinated with FMD inactivated virus (iFMDV) formulated with Montanide™ ESSAI IMS D 12802 VG PR adjuvant (802-iFMDV) were protected when they were challenged 4 and 7 days post-vaccination (dpv) with homologous virus. In this work, we describe the successful use of this formulation in cattle. In addition, adjuvant Montanide™ IMS 1313 VG NPR was also tested. 802-iFMDV vaccine was able to confer 100% protection against viral challenge at 4 and 7 dpv, while eliciting low antibody levels, at 7 dpv. 1313-iFMDV vaccine induced protection in 60% of cattle. At 4 dpv, 1313-iFMDV vaccinated animals presented increased levels of IFNγ but not of macrophages. At 4 and 7 dpv, macrophages, IFNγ, IgA and IgG1 antibodies against FMDV in nasal mucosa, and opsonophagocytosis were increased in animals vaccinated with 802-iFMDV indicating that these phenomena could be involved in protection.It is the first time that total protection against FMDV at early stages post-vaccination is reported using a single dose of the formulation iFMDV plus Montanide™ ESSAI D IMS 12802 VG PR adjuvant.
    Vaccine 01/2014; · 3.77 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Introduction Foot-and-mouth disease virus (FMDV) is a highly variable RNA virus existing in seven different serotypes. The antigenic variability within one serotype can limit the cross-reactivity and therefore the probable cross-protection of vaccine strains within this serotype. Serological assays are routinely used during the process of selecting the most appropriate vaccine strain for protection against given field isolates. This study presents the results of a small scale vaccine matching ring test for an FMD A 24 Cruzeiro vaccine using a liquid phase blocking ELISA (LPBE). The goal was to improve the comparability of r 1 values from different laboratories. Methods Vaccine matching is performed by determining the log 10 antibody titer (t i) of a bovine post vaccinal serum (BVS) to the homologous virus strain (t i ho) and by comparing this to a t i against a heterologous strain (t i he). An r 1 value is calculated as the antilog of {t i he -t i ho } what results in a ratio between 0 and 1. Values above 0.4 are considered cross-reactive and possibly cross-protective, values between 0.2 and 0.4 are weak cross-reactive and values below 0.2 are non-cross-reactive. The selected FMD viruses were the homologous A 24 strain and 3 heterologous strains (A1: A/Argentina/01, A2:A81/Arg/87, A3:A/Arg/00). In vivo data indicates that the A 24 vaccine does not cross-protect against the heterologous strains. Three BVS pools were created: Pool A and B consisted of 5 BVS with high and medium log 10 antibody titers (t i) to A 24 (3.1 and 2.5, respectively). Pool C was a mixture of pool A and B and had an intermediate t i of 2.8. The pools were divided over 9 samples (3 samples per pool).
    EPIZONE 6th ANNUAL MEETING, Brigthon UK; 06/2012
  • [Show abstract] [Hide abstract]
    ABSTRACT: Introduction Foot-and-mouth disease virus (FMDV) is a highly variable RNA virus existing in seven different serotypes. The antigenic variability within one serotype can limit the cross-reactivity and therefore the probable cross-protection of vaccine strains within this serotype. Serological assays are routinely used during the process of selecting the most appropriate vaccine strain for protection against given field isolates. This study presents the results of a small scale vaccine matching ring test for an FMD A 24 Cruzeiro vaccine using a liquid phase blocking ELISA (LPBE). The goal was to improve the comparability of r 1 values from different laboratories. Methods Vaccine matching is performed by determining the log 10 antibody titer (t i) of a bovine post vaccinal serum (BVS) to the homologous virus strain (t i ho) and by comparing this to a t i against a heterologous strain (t i he). An r 1 value is calculated as the antilog of {t i he -t i ho } what results in a ratio between 0 and 1. Values above 0.4 are considered cross-reactive and possibly cross-protective, values between 0.2 and 0.4 are weak cross-reactive and values below 0.2 are non-cross-reactive. The selected FMD viruses were the homologous A 24 strain and 3 heterologous strains (A1: A/Argentina/01, A2:A81/Arg/87, A3:A/Arg/00). In vivo data indicates that the A 24 vaccine does not cross-protect against the heterologous strains. Three BVS pools were created: Pool A and B consisted of 5 BVS with high and medium log 10 antibody titers (t i) to A 24 (3.1 and 2.5, respectively). Pool C was a mixture of pool A and B and had an intermediate t i of 2.8. The pools were divided over 9 samples (3 samples per pool).
  • [Show abstract] [Hide abstract]
    ABSTRACT: The World Organisation for Animal Health (OIE) Terrestrial Manual and the European Pharmacopoeia (EP) still prescribe live challenge experiments for foot-and-mouth disease virus (FMDV) immunogenicity and vaccine potency tests. However, the EP allows for other validated tests for the latter, and specifically in vitro tests if a "satisfactory pass level" has been determined; serological replacements are also currently in use in South America. Much research has therefore focused on validating both ex vivo and in vitro tests to replace live challenge. However, insufficient attention has been given to the sensitivity and specificity of the "gold standard"in vivo test being replaced, despite this information being critical to determining what should be required of its replacement. This paper aims to redress this imbalance by examining the current live challenge tests and their associated statistics and determining the confidence that we can have in them, thereby setting a standard for candidate replacements. It determines that the statistics associated with the current EP PD(50) test are inappropriate given our domain knowledge, but that the OIE test statistics are satisfactory. However, it has also identified a new set of live animal challenge test regimes that provide similar sensitivity and specificity to all of the currently used OIE tests using fewer animals (16 including controls), and can also provide further savings in live animal experiments in exchange for small reductions in sensitivity and specificity.
    Vaccine 06/2011; 29(33):5467-73. · 3.77 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The necessity of avoiding the use of animals in vaccine potency testing has been widely recognized. The repeatability and reproducibility of the Expected Percentage of Protection (EPP) as a serological potency surrogate for A24 Cruzeiro foot-and-mouth disease virus (FMDV) strain was assessed, and compared with the results obtained with challenge in the Protection against Podal Generalization (PPG) test. To determine the EPPs, the serum titers obtained by liquid phase blocking competitive ELISA (lpELISA) and virus neutralization (VNT) in 10 potency trials using the same A24 Cruzeiro vaccine, were interpolated into previously validated logit transformation curves that correlate PPG with serology. Indirect serological assessment of vaccine matching between the serotype A FMDV strains A24 Cruzeiro and A/Argentina/01 was also carried out by lpELISA and VNT. The results obtained in this study strongly support the replacement of challenge tests for vaccine potency by indirect serological assays, at least for A24 Cruzeiro FMDV strain. While determination of EPPs by lpELISA titers showed an excellent repeatability, reproducibility and concordance with PPG for vaccine potency, assessments of cross-protection by VNT titers were more consistent with the PPG outcome.
    Vaccine 08/2010; 28(38):6235-41. · 3.77 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The selection of matching strains for use in outbreaks of foot-and-mouth disease (FMD) virus can be assessed in vivo or by serological r-value determination. Sera from animals involved in vaccine potency and cross-protection trials performed using the "Protection against Podal Generalization" (PPG) test for two serotype A strains were collected and analyzed by the virus neutralization test (VNT) and liquid-phase ELISA (lpELISA) in three laboratories. The average VNT r-values for medium and high serum titer classes from the A(24) Cruzeiro vaccinated animals were in line with the A/Arg/01 heterologous PPG outcome for all testing laboratories, suggesting that the vaccine strain A(24) Cruzeiro is unlikely to protect against the field isolate A/Arg/01. The corresponding lpELISA r-values were slightly higher and indicate a closer relationship between both strains. Pooling of serum samples significantly reduced the inter-animal and inter-trial variation. The results suggest that a suitable reference serum for vaccine matching r-value experiments might be a pool or a medium to high VNT or lpELISA titer serum. Furthermore, the VNT seems to produce the most reproducible inter-laboratory results. More work is, however, needed in order to substantiate these claims.
    Vaccine 12/2008; 27(5):741-7. · 3.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The level of protection conferred by foot-and-mouth disease (FMD) vaccines in primovaccinated animals primarily depends on the potency of the vaccine and the relatedness of the vaccine strain and circulating field isolate. The "Gold Standard" FMD vaccine potency test is the in vivo test performed in the target species. The objective of the study was to determine the precision of the in vivo "Protection against Podal Generalisation" (PPG) FMD vaccine potency test in cattle using homologous (vaccine quality control) and heterologous (vaccine matching) viral challenge. The overall level of protection induced by the A(24) Cruzeiro/Brazil/55 vaccine used in six homologous PPG tests was 88.5%. Vaccine accordance (VACC) and vaccine concordance (VCON) were estimated to be 75.9% and 73.7%, respectively. In four heterologous challenge PPG tests, the overall level of cross-protection induced by the A(24) Cruzeiro/Brazil/55 vaccine against A Argentina/2001 challenge was 26.6%, with VACC and VCON values of 65.7% and 59.2%, respectively. Results indicate that the homologous PPG test is more reliable than the European Pharmacopoeia potency test, but that a larger number of animals should be used in order to increase the test's statistical power. In this regard, indirect alternative tests for vaccine potency and vaccine matching merit consideration.
    Vaccine 07/2008; 26(27-28):3432-7. · 3.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: FIELD ASSESSMENT OF THE ENZYME LINKED IMMUNOSORBENT ASSAY FOR FOOT-AND-MOUTH DISEASE VIRUS DIAGNOSIS AND TYPING. The objective of the present study was to evaluate the enzyme linked immunosorbent assay (ELISA) in comparison with the complement fixation test (CFT) for the diagnosis and typing of foot-and-mouth disease (FMD) virus (FMDV). Diagnostic material was epithelium from either suspected cases of FMD or from animals experimentally infected with FMDV. Epithelial suspensions and supernatant fluids from cell culture passage were assayed by CFT and ELISA. The superiority of the ELISA over the CFT was demonstrated: 1) the detection rate was 23% higher than that of CFT on original (epithelial) suspensions (OS) submissions of all sample (positive and negative) and 30% higher on supernatant fluids from cell culture passage, 2) the detection rate of ELISA on OS of confirmed positive samples was 28% higher than that of CFT, 3) no significant differences were observed in the detection and typing rates between the PANAFTOSA and FAO/IAEA ELISA kits (P
    01/2007;
  • [Show abstract] [Hide abstract]
    ABSTRACT: The use of foot-and-mouth disease (FMD) vaccines that do not induce antibodies against non-structural proteins (NSP) is extremely relevant for the demonstration of regions "free of FMDV infection" and control strategies. In this study cattle were primed and boosted with five doses of oil vaccines containing high antigenic payloads on days 0, 90, 130, 160 and 200. The serological response against NSP was measured using four commercially available assays: two 3ABC-ELISAs; one 3B-ELISA (and complementary 3A-ELISA) and an enzyme-immunotransfer blot assay (EITB). Additionally, locally produced NSP antibodies detection reagents and VIAA antibodies were evaluated. A high level of specific immune response against vaccine strains was shown. After four doses of vaccine, non-reactive animals were detected by any of the NSP assays. After the fifth immunization, 2 of 17 animals were reactive in one ELISA kit, but these samples proved negative by confirmatory tests. Antibodies against NSP were not detected in single dose immunized cattle. The principle of the NSP-ELISA used as a screening test for large sero-surveys in South America is established and this paper emphasizes the importance of using vaccines that have demonstrated no interference with NSP antibodies detection assays.
    Vaccine 12/2004; 23(1):69-77. · 3.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This paper describes the antigenic and molecular characterisation of foot-and-mouth disease virus (FMDV) strains isolated during the 2000-2002 epidemic in Argentina, and the strategy implemented for disease control. Two different FMDV serotypes, O and A, were involved. Of the various field isolates studied, two distinct O1 lineages (strains Corrientes/00 and Misiones/00) and two serotype A lineages (A/Argentina/00 and A/Argentina/01 prototypes) were identified. The genome sequences of these strains were compared with sequences of previous regional isolates and sequences of vaccine strains. O1 strains were found to be related to regional strains while serotype A strains were found to be more distanced from them. The updating of the antigenic composition of the vaccines used in the emergency was a key issue, since the outbreaks stopped shortly after the implementation of the vaccination programs. The O1 strains quickly disappeared from the field following strict control measures and the use of vaccines containing O1/Campos strain. However, in the case of the A serotype strains, the situation was different, since the use of a vaccine containing strain A24/Cruzeiro yielded acceptable levels of protection only after re-vaccination. Therefore, the new field strains A/Argentina/00 and A/Argentina/01 were incorporated into the vaccine, leading to an effective control of the disease. Viral circulation greatly diminished, as indicated by the significant reduction in the number of outbreaks and in the number of animals with antibodies against non-structural proteins. Satisfactory levels of protective antibodies were subsequently detected in the cattle population (above 75% protection). The absence of outbreaks after January 2002 indicated that the epidemic was controlled.
    Vaccine 11/2004; 22(31-32):4149-62. · 3.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We present a comparison of methods for evaluating the potency of foot and mouth disease vaccine in the laboratory. The anti-FMDV antibodies (Ab) in vaccinated mice were tested by liquid phase (lp) ELISA, solid phase (sp) ELISA and virus neutralization (VN), and were compared with the Ab titres detected by lpELISA, which is the official test in Argentina for testing the potency of FMD vaccines and protection against a virulent challenge in cattle. The results demonstrated that it is possible to relate the Ab levels induced in vaccinated mice with both the Ab and protective responses elicited in cattle. Furthermore, it was found that the anti-FMDV Ab titres in mice detected by lpELISA 14 days after vaccination should be an accurate parameter for predicting the results of the challenge test in cattle. Thus, this test in mice appears to be an inexpensive and rapid alternative for testing FMD vaccines in cattle.
    Veterinary Research Communications 06/2000; 24(4):261-73. · 1.08 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We report the construction of a recombinant vaccinia virus expressing the precursor for the four structural proteins of FMD virus (FMDV) (P1) strain C3Arg85 using a procedure for isolation of recombinant vaccinia viruses based solely on plaque formation. Adult mice vaccinated with this recombinant vaccinia virus elicited high titers of neutralizing antibodies against both the homologous FMDV and vaccinia virus, measured by neutralization assays. Liquid phase blocking sandwich enzyme-linked immunosorbent assays (ELISAs) using whole virus as antigen showed high total antibody titers against homologous FMDV, similar to those induced by the conventional inactivated vaccine. When ELISAs were carried out with heterologous strains A79 or O1Caseros as antigens, sera from animals vaccinated with the recombinant virus cross-reacted. Mice boosted once with the recombinant vaccinia virus were protected against challenge with infectious homologous virus. These results indicate that recombinant vaccinia viruses are efficient immunogens against FMDV when used as a live vaccine in a mouse model.
    Vaccine 05/2000; 18(21):2231-8. · 3.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    Veterinary Immunology and Immunopathology 08/1999; 69(1):11-22. · 1.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A sero-epidemiological survey was conducted in two districts in Argentina between 1993 and 1995, to provide additional information on the epidemiology of foot and mouth disease (FMD) in Argentina and to assess the level of immunity in cattle populations, and the circulation of FMD virus. As part of the final stage of this survey, a comparison was made of the results obtained by the enzyme-linked immunosorbent assay (ELISA) and agar gel immunodiffusion techniques. Levels of population immunity against the four types of virus included in the vaccine increased progressively during the period of the survey until, in 1995, at the end of the vaccination period, the percentage of animals possessing adequate levels of protection was approximately 77% in yearlings, and more than 94% in cattle over one year old. During the three-year study, there was a clear tendency for viral activity to diminish, until in 1995 when between 3% and 0.6% were positive to the agar gel immunodiffusion test for the antigen associated with viral infection. By contrast, the ELISA detected antibody in about five times as many animals. The authors show how the increase in the level of population immunity was accompanied by a fall in viral activity.
    Revue scientifique et technique (International Office of Epizootics) 01/1998; 16(3):784-92. · 0.69 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The analysis of sera obtained from animals vaccinated or revaccinated with inactivated vaccines against foot and mouth disease (FMD) virus showed that these vaccines induced antibodies against the virus infection-associated (VIA) antigen, detectable by agar gel immunodiffusion (AGID). The present study evaluates the antibody response to protein 3D and the VIA antigen (VIAA) of FMD virus induced by different vaccines in a group of 51 calves. This response was detected using AGID and a liquid-phase blocking sandwich enzyme-linked immunosorbent assay (ELISA) for anti-3D antibodies (ELISA-3D). No anti-VIAA or anti-3D antibodies were detected after the initial vaccination. Following revaccination, animals giving positive results were detected by both methods. This immune response disappeared 60-120 days post-revaccination (dprv) according to the AGID method, and 90-180 dprv when ELISA-3D was used. Samples of oesophageal-pharyngeal fluid obtained from animals that remained positive for anti-VIAA antibodies at 90-120 dprv gave negative results for viral isolation, indicating that the transitional antibody response induced by the vaccine was due to the presence of non-structural antigens in the vaccine and not to viral infection. These results indicate that the ELISA-3D method could be used as a complementary method for sero-epidemiological studies as an indirect indicator of viral activity, as long as the age and vaccination status of the animals being sampled are taken into consideration.
    Revue scientifique et technique (International Office of Epizootics) 01/1998; 16(3):833-40. · 0.69 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The IgG isotype response in Balb/c mice infected with FMDV or immunized with different vaccine formulations using inactivated virus particles as antigen was analyzed at various times post-inoculation. For this purpose an ELISA based on polyclonal antibodies for detection and quantification of mouse IgG isotypes with FMD virus (FMDV) specificity was developed. Three immunomodulators, which have been shown to be very effective in inducing strong and long-lasting antibody responses (Bahnemann, Arch. Virol. 1975, 47, 47-56; Polatnik and Bachrach, Appl. Microbiol. 1964, 12, 368-376), were employed to formulate different vaccines using aqueous and oil vehicles: a water-soluble fraction of the cell wall of Mycobacterium sp., a purified extract of lipopolysacharide from Brucella ovis and a synthetic lipoamide, Avridine. Infected animals between 14 and 60 days post-inoculation (d.p.i.) showed responses dominated by IgG2b, followed by IgG1, IgG2a and IgG3, respectively. The IgG3 isotype was the first, together with IgG1, to be elicited during the first 7 days after infection, whereas no IgG3 activity was detected in vaccinated animals at any time. With formulations including immunomodulators, persisting high levels of IgG2b (similar to those of infected animals) were detected until 180 d.p.i., while with conventional vaccines IgG2b responses were detected up to 60 d.p.i. Animals vaccinated with formulations including these immunomodulators presented an augmented resistance to viral challenge at 210 d.p.i. in relation with those immunized with conventional vaccines. The possible relationship of these differences in the isotype response and protection is discussed.
    Vaccine 08/1995; 13(10):953-60. · 3.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Calves born to vaccinated cows under the regular annual vaccination programme were vaccinated at different ages using commercial quadrivalent (01, A79, A87 and C85 FMDV strains) vaccine emulsified in oil adjuvant. The antibody responses of vaccinated calves were evaluated using liquid-phase blocking sandwich ELISA. All calves 20, 30 and 40 days old having high maternal antibody titres responded well to vaccination. Moreover, 25-57% of vaccinated calves showed protective antibody titres both at 90 and 120 days post-vaccination (d.p.v.), whereas none of the non-vaccinated animals achieved these levels. Calves aged 3-4 months with non-protective levels of colostral-derived antibodies responded with high antibody titres to vaccination which persisted for at least 4 months. In both groups of calves a certain degree of suppression of postvaccinal response was observed which was related to colostral antibody titres. Our results suggest that in order to reduce the proportion of calves susceptible to infection it is advisable to immunize calves as young as 20 days old to induce acceptable antibody titres for the following 4 months. In addition, a second vaccination 60 d.p.v. ensures high antibody levels in high disease risk areas.
    Vaccine 08/1995; 13(10):909-14. · 3.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Serum neutralization (SN), indirect immunofluorescence (IFI) and enzyme-linked immunosorbent assay (ELISA) were compared for their sensitivity and specificity to detect bovine serum antibodies to Bovine Herpesvirus type 1 on 105 bovine serum samples. High correlation coefficients among all three techniques were observed, showing a higher sensitivity for the ELISA test. Due to its simplicity and its feasibility to be adopted in less equipped laboratories, the ELISA test is recommended for large scale epizotiological studies, serological diagnosis and detection of reactive animals.
    Revista Argentina de microbiología 22(4):192-8. · 0.54 Impact Factor