PPR Vaccine Research Articles

Evaluation of different adjuvants to the inactivated PPR vaccine

Evaluation of different adjuvants to the inactivated PPR vaccine

Effects of <i>peste des petit ruminants</i> N/75/1 vaccine on nasal bacterial flora and clinical indices in Red Sokoto goats

Peste des petit ruminants virus (PPRv) and Mannheimia haemolytica have been commonly implicated in naturally occurring pneumonia in sub-Saharan Africa and account for huge economic losses as they are associated with high morbidity and mortality. The Nigerian 75/1 PPR vaccine has been proven to be efficacious in the control of PPR. However, there is a paucity of information on the ability of this live attenuated vaccine to modulate bacteria of the nasal flora to control or confer protection against secondary bacterial infection induced especially by M. haemolytica. Nasal swabs and blood samples were collected for bacterial count and serology respectively. This study describes the effect of the N/75/1 PPR vaccine on the nasal bacteria flora and clinical indices of Red Sokoto goats. Ten (10) Red Sokoto goats were divided into two groups of five animals each. In one group, 1ml of PPR vaccine (2.5 TCID50) was administered subcutaneously while the other group served as control and 1ml of normal saline was administered subcutaneously. The results showed that for the PPR vaccinated group, although there was a significant decrease (p≤0.05) in nasal bacteria counts for Mannheimia haemolytica, Pasteurella multocida and Escherichia coli compared to the control group it was not sufficient to clear out these potentially pathogenic bacteria from the nasal flora. Also, in the PPR-vaccinated group, the only clinical symptom observed was a mild transient and self-limiting hyperthermia at about 2 weeks post-vaccination which may be attributed to the initiation and enhancement of immune responses. Hence, it can be deduced that the PPR vaccine may moderately inhibit the colonization of certain pathogenic bacteria of the nasal microbial flora but however, it is incapable of conferring total immunity against the secondary bacterial infection in naturally occurring pneumonia.

In vitro and in vivo analyses of co-infections with peste des petits ruminants and capripox vaccine strains

BackgroundPeste des petits ruminants (PPR) and goat pox (GTP) are two devastating animal epidemic diseases that affect small ruminants. Vaccination is one of the most important measures to prevent and control these two severe infectious diseases.MethodsIn this study, we vaccinated sheep with PPR and POX vaccines to compare the changes in the antibody levels between animals vaccinated with PPRV and POX vaccines alone and those co-infected with both vaccines simultaneously. The cell infection model was used to explore the interference mechanism between the vaccines in vitro. The antibody levels were detected with the commercial ELISA kit. The Real-time Quantitative PCR method was employed to detect the viral load changes and cytokines expression after the infection.ResultsThe concurrent immunization of GTP and PPR vaccine enhanced the PPR vaccine's immune effect but inhibited the immune effect of the GTP vaccine. After the infection, GTP and PPR vaccine strains caused cytopathic effect; co-infection with GTP and PPR vaccine strains inhibited the replication of PPR vaccine strains; co-infection with GTP and PPR vaccine strains enhanced the replication of GTP vaccine strains. Moreover, virus mixed infection enhanced the mRNA expressions of TNF-α, IL-1β, IL-6, IL-10, IFN-α, and IFN-β by 2–170 times. GTP vaccine strains infection alone can enhanced the mRNA expression of IL-1β, TNF-α, IL-6, IL-10, while the expression of IFN-α mRNA is inhibited. PPR vaccine strains alone can enhanced the mRNA expression of IFN-α, IFN-β, TNF-α, and has little effect the mRNA expression of IL-1β, IL-6 and IL-10. The results showed that GTP and PPR vaccine used simultaneously in sheep enhanced the PPR vaccine's immune effect but inhibited the immune effect of the GTP vaccine in vivo. Furthermore, an infection of GTP and PPR vaccine strains caused significant cell lesions in vitro; co-infection with GTP + PPR vaccine strains inhibited the replication of PPR vaccine strains, while the co-infection of GTP followed by PPR infection enhanced the replication of GTP vaccine strains. Moreover, virus infection enhanced the expressions of TNF-α, IL-1β, IL-6, IL-10, IFN-α, and IFN-β.ConclusionsPeste des petits ruminants and capripox vaccine strains interfere with each other in vivo and vitro.

Growth and reproductive performances of Hilly Brown Bengal goat under semi-intensive management condition at Naikhongchari hilly areas of Bangladesh

The objective of the study was to evaluate the growth and reproductive performances of Hilly Brown Bengal (HBB) goats of different generations and conducted at Naikhongchari Regional Station Research Farm of Bangladesh Livestock Research Institute. Goats were reared in a plastic slated floor under semi-intensive system and were allowed to graze for 6-7 hours per day. Animals were given a concentrate mixture containing 17% CP, 11 MJ ME/kg DM provided twice daily in the morning and evening at the rate of 1% of their body weight. All goats were kept separately according to sex and age groups to avoid random mating. Natural mating program was performed to improve the economically important traits. Goats were de-wormed and diping on regular intervals and only PPR vaccine was given at the age of 2 months. Data on productive, reproductive and disease incidence of goat were recorded regularly and were analyzed. Results showed that Kid Birth Weight of HBB goats were significantly (P<0.01) differ among generations. Birth weight of G3 (1.21±0.013 kg) was higher than G5, G4, G2 and G1 (1.11±0.01 kg). Goat body weight of 3, 6 and 9 months age were non-significant among generations. The age and weight at first conception were significantly (p<0.05) differ among generation. Age at first conception was lower of G4 (301.57±9.06 days) and higher of G1 (259.80±18.87 days) but body weight at first conception of G1 (12.23±0.47 kg) was higher and G4 was lower (10.65±0.52 kg). Age at first kidding, gestation length and kidding interval was not significant (P>.05) effect on generations. Parity had no significant (P>.05) effect on kid birth weight but significantly (p<0.01) differ of Kid litter weight and litter size. According to birth type single kid was highest birth weight (1.21±0.08 kg) than double kid followed by triplet and quadruplet. Mortality percentage of HBB kids at the age of 0-90 days were 13.08±0.23%. It may be concluded that kid birth weight, age and weight at first conception of HBB goat were significantly (P<.05) affected on generation but age at first kidding, gestation length and kidding interval were non significantly (P<.05) affected.
 Asian Australas. J. Biosci. Biotechnol. 2020, 5 (2), 72-77

Sero-prevalence of peste des petits ruminants virus antibodies in sheep and goats from the Sudan, 2016-2017.

Recently, severe outbreaks of PPR among small ruminants were reported regularly in different parts of the country leading to significant economic losses. Between 2016 and 2017, a total of 320 sera were collected from sheep (258) and goats (62) from PPR suspected outbreaks from four different States in the Sudan. Screening of sera for the presence of PPRV antibodies by competitive ELISA revealed an overall antibodies sero-prevalence of 80.9% (259/320, 95% CI 20.5-28) among sheep and goats. On the species basis, sheep sera yielded the higher antibodies sero-prevalence of 84.5% (218/258, 95% CI 16.7-24.1) compared to a lower sero-prevalence of 66.1% (41/62, 95% CI 28.5-51.1) obtained from goats sera. Within Sudanese States where outbreaks occurred, the highest overall sero-prevalence of PPRV antibodies in sheep and goats was demonstrated in River Nile State 90.3% (159/176 sera, 95% CI 12.8-18.2) while the lowest incidence was present in Northern State 00.0% (0/2 sera, 95% CI 69.9-72.2). Of note, higher sero-prevalence values were achieved in this study than previously documented. Results of the present study indicated that PPR is currently circulating widely in the Sudan and still is a leading cause of disease outbreaks and higher fatalities in small ruminants. Therefore, the effective PPR vaccine is recommended to cover all parts of the Sudan to prevent the occurrence of disease outbreaks.

Comparative potentiality study of three different vero cell culture systems for production of PPR Vaccine

Comparative potentiality study of three different vero cell culture systems for production of PPR Vaccine

Preparation of Hyperimmune Serum against Peste Des Petits Ruminants to Be Used in Emergency Cases

Hyperimmune serum against peste des petites ruminants virus was successfully prepared in horses where it was found to have specific peste des petites ruminants virus (PPRV) neutralizing antibodies titer of 1024/ml as determined by serum neutralization test (SNT). Quality control testing of such serum revealed that it was free from bacterial, fungal and mycoplasma contaminants as tested on specific media and safe when inoculated in sheep. Passive induced immunity in sheep was persisted with a protective level up to 5 weeks post inoculation as determined by SNT and ELISA. On the other side, inoculation of PPR vaccine with antisera in sheep showed similar findings with slight rise in antibody titer. Depending on the obtained results, it could be concluded that horse anti-PPR serum is of a significant importance and can help to protect and control PPR infections especially in case of outbreaks that need rapid management.

Expression and characterization of immunodominant region of fusion protein of peste des petits ruminants virus in E. coli

The present study envisages expression of immunodominant ectodomain of peste des petits ruminants virus (PPRV) fusion (F) protein in Escherichia coli BL21 (DE3) and its characterization to assess its immunoreactivity. The ectodomain gene sequences corresponding to 222 amino acids, was amplified from PPR vaccine virus, cloned into pET33b vector and expressed in E. coli at an optimal temperature of 37°C with 1mM IPTG for 5h. The expressed and Ni-NTA purified PPRV F protein (31kDa) was characterized by SDS-PAGE and Western blot using anti-his-tagged-conjugate, anti-serum raised against recombinant PPRV F protein, hyper immune serum against whole PPRV and convalescent sera from sheep and goats. The expressed protein was assessed for its immunoreactivity by ELISA and immunoblotting. The antibody response mounted against the recombinant PPRV F protein in immunized rabbits was detected by recombinant PPRV F antigen based indirect ELISA, and whole virus antigen based indirect ELISA, which indicating the native confirmation of the expressed protein in E. coli. Indirect ELISA was optimized using known true positive and negative sera with respect to PPRV antibodies in order to assess the reactivity of the PPRV F protein in detecting PPRV F antibodies in small ruminants. The E. coli expressed recombinant ectodomain of PPRV F protein exhibits immunoreactivity and was able to specifically detect PPRV antibodies in response to both vaccination and disease in natural host.

Changes in Humoral Immunity Due to Different Doses of Levamisole in Ppr Vaccinated Goats

Healthy, PPRV sero-negative Black Bengal goats (12) were divided into three groups and levamisole was injected in two groups @ 2.5 and @ 5.0 mg/kg body weight with three doses at 24 h intervals. After seven days all the animals were vaccinated with PPR vaccine. On i-ELISA, the magnitude of antibody titre in serum samples was more in levamisole and PPR vaccine treated groups than only PPR vaccine treated group. It was concluded that levamisole may be injected @ 2.5 to 5.0 mg/kg body weight to get stronger immunity against PPR in infection-prone region.

VeroNectin-4 is a highly sensitive cell line that can be used for the isolation and titration of Peste des Petits Ruminants virus

Peste des Petits Ruminants virus (PPRV) is a member of the Morbillivirus subgroup of the family Paramyxoviridae, and is one of the most contagious diseases of small ruminants throughout Africa and the rest of the world. Different cell lines have previously been used to isolate PPRV but with limited success. Thus, to improve the isolation of Morbilliviruses, human, canine, and goat homologues of the lymphocyte receptor signaling lymphocyte activation molecule (SLAM) have been introduced into cells that can support virus replication. However, the amino acid sequence of SLAM varies between species, and often requires adaptation of a particular virus to different versions of the receptor. The protein sequence of Nectin-4 is highly conserved between different mammals, which eliminate the need for receptor adaptation by the virus. Cell lines expressing Nectin-4 have previously been used to propagate measles and canine distemper viruses. In this study, we compared infections in Vero cells expressing canine SLAM (VeroDogSLAM) to those in Vero cells expressing Nectin-4 (VeroNectin-4), following inoculations with wild-type strains of PPRV. Virus isolation using VeroNectin-4 cells was successful with 23% of swabbed samples obtained from live infected animals, and was 89% effective using post-mortem tissues of infected sheep. By contrast, only 4.5% efficiency was observed from swab samples and 67% efficiency was obtained in virus isolation from post-mortem tissues using VeroDogSLAM cells. The average incubation period for virus recovery from post-mortem tissues was 3.4 days using VeroNectin-4 cells, compared with 5.5 days when using VeroDogSLAM cells. The virus titers of PPRV obtained from VeroNectin-4 cells were also higher than those derived from VeroDogSLAM cells. A comparison of the growth kinetics for PPRV in the two cell lines confirmed the superiority of VeroNectin-4 cells for PPR diagnostic purposes and vaccine virus titration.

Immunomodulatory effect of levamisole on PPR vaccine in goats and change in haematological profile

Levamisole is an anthelmintic and synthetic immunomodulator. Effect of levamisole on PPR vaccine in goat model was evaluated in this study. Healthy, sero negative for PPR infection 12 Black Bengal goats were divided into three groups. Levamisole was injected @ 2.5 mg/kg b.wt. and @ 5.0 mg/kg b.wt. in two groups respectively. After seven days all animals were vaccinated with PPR cell culture vaccine. Blood samples were collected from animals at 0 day, 7th day, 14th day, 21st day and 30th day. Serum was separated and used in indirect ELISA for qualitative and quantitative assay of antibody titer. EDTA mixed blood sample was used for determination of immunity induced blood cells number. Antibody titer and immunity induced blood cells number were more in the Levamisole and vaccine treated groups than only vaccine treated group. So, levamisole acted as an immunomodulator when it was used prior PPR vaccine in goats.

Haematological changes associated with intranasal and parenteral routes of vaccination against Peste des petits ruminants in West African dwarf goats

The haematological indices of West African dwarf goats vaccinated against Peste des petits ruminants virus via the parenteral and the mucosal (intranasal) routes were studied and compared with an unvaccinated control. The post vaccination packed cell volume (PCV) and haemoglobin (Hb) concentrations of the vaccinated groups did not show any statistically significant difference (p > 0.05) from the unvaccinated control. However, a statistically significant difference was observed in the total white blood cell (WBC) counts between the vaccinated groups and the unvaccinated control, as well as between those vaccinated via the mucosal route and those vaccinated via the parenteral routes, though all within the normal reference values for West African dwarf goats. Differential WBC counts showed the significant difference to be due to increase in lymphocyte population, suggesting that PPR vaccine administered via the different routes was able to stimulate a cellular immune response which is mostly lymphoproliferative. Thus, it can be suggested that intranasal vaccination against Peste des petits ruminants as well as vaccination via the conventional route is safe.

Protective immune response of live attenuated thermo-adapted peste des petits ruminants vaccine in goats.

Virulent isolate of peste des petits ruminants virus (PPRV) of Indian origin (PPRV Jhansi 2003) initially adapted in Vero cells was further propagated in thermo-adapted (Ta) Vero cells grown at 40°C for attaining thermo-adaption and attenuation of virus for development of Ta vaccine against PPR in goats and sheep. The virus was attenuated up to 50 passages in Ta Vero cells, at which, the virus was found sterile, innocuous in mice and guinea pigs and safe in seronegative goats and sheep. The developed vaccine was tested for its immunogenicity in goats and sheep by subcutaneous inoculation of 100 TCID50 (0.1field dose), 10(3) TCID50 (one field dose) and 10(5) TCID50 (100 field doses) of the attenuated virus along with controls as per OIE described protocols for PPR vaccine testing and were assessed for PPRV-specific antibodies 7-28days post vaccination (dpv) by PPR competitive ELISA and serum neutralization tests. The PPRV antibodies were detected in all immunized goats and sheep and goats were protective when challenged with virulent PPRV at 28th dpv along with controls for potency testing of the vaccine. The attenuated vaccine did not induce any adverse reaction at high dose (10(5) TCID50) in goats and sheep and provided complete protection even at low dose (10(2) TCID50) in goats when challenged with virulent virus. There was no shedding and horizontal transmission of the attenuated virus to in-contact controls. The results indicate that the developed PPR Ta attenuated virus is innocuous, safe, immunogenic and potent or efficacious vaccine candidate alternative to the existing vaccines for the protection of goats and sheep against PPR in the tropical countries like India.

Study on passive immunity: Time of vaccination in kids born to goats vaccinated against Peste des petits ruminants

In this study, the decay of maternal peste des petits ruminants virus (PPRV) antibodies in kids born to goats vaccinated with Asian lineage IV PPR vaccine and the efficacy of passive immunity against PPRV was assessed to determine the appropriate period for vaccination in kids. Serum samples collected from kids born to vaccinated, unvaccinated and infected goats at different time intervals were tested by PPR competitive ELISA and serum neutralization test (SNT). Maternal antibodies in kids were detectable up to 6 months with a decline trend from the third month onwards and receded below the protective level by the fourth month. The kid with an SN titre of 1:8 at the time of immunization showed significant PPRV specific antibody response (percentage inhibition of 76; SN titers >1:16), when tested on 21 day post-vaccination and was completely protected from infection upon virulent PPRV challenge. Similarly, the kid with 1:8 SN titers was completely protected from PPR infection on active challenge. Therefore, PPR vaccination is recommended in kids, aged 4 months and born to immunized or exposed goats. This could be a suitable period to avoid window of susceptibility in kids to PPRV and the effort to eliminate PPR infection from susceptible populations.

Effects of PPR Vaccine on Goat Haematology in Tangail District of Bangladesh

Effects of PPR Vaccine on Goat Haematology in Tangail District of Bangladesh

A rapid and sensitive one step-SYBR green based semi quantitative real time RT-PCR for the detection of peste des petits ruminants virus in the clinical samples

A sensitive and rapid single step real time (rt) RT-PCR was standardized using one-step Brilliant SYBR Green kit® for detection and semi-quantitation of peste des petitis ruminants virus (PPRV) using the virus RNA and matrix (M) protein gene-specific primers and compared with established conventional RT-PCR and TaqMan RT-PCR. The assay amplifies a 124 bp fragment of the PPRV M gene with T(m) of 78.28 to 78.50. The assay was linear within a range of 50 ng to 0.5 fg total virus RNA with a detection limit (sensitivity) of 0.5 fg. Based on the serial dilution of the live-attenuated PPR vaccine virus, the detection limit was ~0.0001 cell culture infectious dose 50% units (TCID(50)). Additionally, swab materials spiked with known titre of vaccine virus were equally well detected in the assay. The standardized rt RT-PCR was easily employed for the detection of PPRV nucleic acid directly in the field and experimental clinical samples. The assay detected the PPRV nucleic acid as early as 3 day post infection (dpi) and up to 20 dpi in swab materials from the experimental samples. The assay was rapid and more sensitive than TaqMan and conventional RT-PCR in the detection of PPRV nucleic acid from the PPR suspected clinical samples of sheep and goats. Therefore, the established, simplified SYBR green rt RT-PCR is an alternative test to the already existing various diagnostic assays and could be useful for rapid clinical diagnosis with advantage in reducing risk of contamination.

Assessment of the duration of maternal antibodies specific to the homologous <i>peste des petits</i> ruminant vaccine “Nigeria 75/1" in <i>Djallonké</i> lambs

The duration of maternal immunity was determined from 112 lambs born from vaccinated ewes with the homologous PPR vaccine “Nigeria 75/1 at day 90 and day 120 of pregnancy. Serum samples were collected from lambs starting from day 15 to day 150 after birth and analyzed using the PPR specific competitive ELISA. At day 75 and day 90 after birth, 70% and 95% of these lambs respectively became negative. So it is recommended to vaccinate lambs against PPR in the interval from 75 to 90 days after birth.

Standardization of large scale production of homologous live attenuated PPR vaccine in India

Live attenuated homologous vaccine against peste des petits ruminants of sheep and goats was produced on a large scale basis in roller culture bottles using seed virus developed at the Indian Veterinary Research Institute, Muktheswar, India. Vero cells between 130-150 passages with six percent foetal calf serum were used for the production of vaccine. The cells were infected with 0.01 multiplicity of infection and harvested when the cytopathic effect was 80%. The vaccine was freezedried in order to maintain the stability of the vaccine. Identity test and titration was performed and the vaccine titre was monitored to be minimum of 10(5)/100 doses. In-house sterility tests and quality control tests using experimental animals and small ruminants were performed. The vacuum and moisture content of the vaccine were also regulated to be within the normal limits.

Determination of Efficacy of Thermostable PPR Live Homologous Vaccine Incubated at Room Temperature for 14 Days

The study was undertaken during the period from July to November 2005, for the first time, to determine the efficacy of thermostable PPR vaccine incubated at -20°C and room temperature (RT) for 14 days which was developed by Bangladesh Livestock Research Institute (BLRI), Savar, Dhaka, in collaboration with and Livestock Research Institute (LRI), Mohakhali, Dhaka. A total of 80 healthy goats of both sexes, aged between 8 to 36 months were divided into three groups as A, B and C. Group A and B comprised of 30 goats each and received thermostable PPR vaccine kept at -20°C and at room temperature (RT) respectively for 14 days, at a dose rate of 1 ml (4 Log10 TCID50 / ml) per goat subcutaneously while group C comprising 20 goats served as non-vaccinated control. At 30 days postvaccination, 3 goats from each vaccinated and non-vaccinated group were challenged with 1 ml (5 GID50) of virulent PPR virus per goat subcutaneously in the mid cervical region. Sera samples were collected from all the groups at pre- and post-vaccination (15 and 30 days postvaccination) and were tested for anti-PPR antibody by competitive enzyme linked immunosorbent assay (C-ELISA). In case of group A, average percent inhibition (PI) values of the sera samples at prevaccination and at 15- and 30 days post vaccination were 11.0 ± 5.7, 62.8 ± 9.9 and 81.5 ±5.9 respectively and in case of group B, were 10.0 ± 4.1, 60.7 ± 9.4 and 79.3 ± 7.2 respectively, which were significantly (p < 0.01) higher than those of non-vaccinated control goats (6.3 ± 3.4, 10.2 ± 3.3 and 13.6 ± 3.7 respectively). The titres of vaccinated goats gradually increased until 30 days postvaccination. The challenge test with virulent PPR virus at 30 days post vaccination showed that the thermostable PPR vaccine with both incubation temperatures at -20°C and RT for 14 days protected all the goats (100%) of groups A and B respectively while all the non-vaccinated control goats were not protected after challenge showing clinical signs of PPR and / or mortality. From the above findings it may be concluded that the thermostable PPR vaccine can be kept at normal environmental temperature (25°-30°C) as long as 14 days without loss of its potency and may be used to prevent PPR in goats in field condition.Key Words: Thermostable PPR vaccine, efficacy, C-ELISAdoi:10.3329/bjvm.v4i1.1524 Bangl. J. Vet. Med. (2006). 4 (1): 43-46