Biology subjects

Borah, P.

Publications and source records attributed to Borah, P..

3 recordsLinked to original sources

bioRxiv2020

Protective efficacy of calcium phosphate nanoparticle adsorbed bivalent subunit vaccine of Pasteurella multocida against homologous challenge in mice

Swine pasteurellosis, caused by Pasteurella multocida capsular types A and D, causes heavy economic loss to the pig farmers. The vaccine presently used is abacterin of Pasteurella multocida capsular type B that is proven to be effective against bovine pasteurellosis. However, its efficacy against swine pasteurellosis is questionable. The present study was carried out to evaluate the efficacy of calcium phosphate nanoparticle adjuvanted bivalent subunit vaccine prepared from Pasteurella multocida capsular types A and D along with a monovalent subunit vaccine prepared from Pasteurella multocida capsular type B in mice. The Alum precipitated bacterin vaccine was used as the control. The bivalent subunit vaccine comprising the immune components of both the capsular types showed significantly higher IgG response than either of the other two vaccines. Both the calcium phosphate nanoparticle adjuvanted vaccines could elicit 100% protection in mice against homologous challenges but the aluminum hydroxide adjuvanted bacterin vaccine could not elicit significant protection. Based on this preliminary work, it was concluded that the bivalent subunit vaccine would be a better option for immunization of swine against swine pasteurellosis. IMPORTANCE OF THE WORKThe swine pasteurellosis is an important economic disease affecting the pig population in the North-eastern part of India that contributes the major pig population. The disease is caused by Serotype A and D of Pasteurella multocida. At present the inactivated vaccine is used that is actually developed against P52 strain of serotype B:2 of Pasteurella multocida, which is mainly involved in haemorrhagic septicaemia (or bovine pasteurellosis) that affects the cattle, buffaloe, sheep and goat. As a result, the present vaccine does not give sufficient protection in pigs but gives significant protection in cattle, buffaloe, sheep and goat. Hence, there is a need of development of vaccine that can address specifically swine pasteurellosis by targeting serotype A and D of Pasteurella multocida.

microbiology↗

bioRxiv2020

Phenotypic and molecular characterization of extended spectrum β-lactamase producing Escherichia coli and Klebsiella pneumoniae isolates from various samples of animal origin from Assam, India

Extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae has become a major threat globally. Here we have characterized ESBL producing E. coli and K. pneumoniae from various sources, studied antibiogram and resistance gene profiles. Out of 385 samples, 31 (8.05%) were positive for ESBL producing E. coli. Such isolates could be recovered from 10.05, 8.33, 15.63, 6.67 and 4.35 per cent of cattle milk, curd, chicken, pork and cattle faeces samples, respectively. A total of 59 (15.32%) samples were positive for ESBL producing K. pneumoniae, which were isolated from 14.35, 6.25, 21.43 and 34.78 per cent cattle milk, chicken, beef and cattle faeces, respectively. All the 90 isolates were confirmed as ESBL producers by CDT and ESBL-E strip tests. Antibiogram revealed that 74.19% and 69.49% of the ESBL producing E. coli and K. pneumoniae isolates, respectively showed resistance to ceftizoxime, 25.81% and 23.73% to both co-trimoxazole and tetracycline, 19.35% and 25.42% to ciprofloxacin, 9.68% and 16.95% to chloramphenicol, 3.23% and 5.08% to pipercillin-tazobactam, and 3.23% and 3.39% to gentamicin. Resistance gene profiling showed blaCTX-M gene as most predominant (100%). The blaTEM gene was found in 54.84% and 55.93%, blaSHV gene in 90.32% and 77.97%, Sul 1 gene in 90.32% and 86.44% of ESBL producing E. coli and K. pneumoniae isolates, respectively. The Int1 gene was detected in 70.97% and 62.71% isolates, while qnrB gene was found in 3.23% and 10.17% of E. coli and K. pneumoniae isolates, respectively.

molecular biology↗

bioRxiv2019

Molecular epidemiology of Japanese Encephalitis Virus in pig population of Odisha, Assam and Manipur states of India

Japanese encephalitis virus (JEV) comes under the family Flaviviridae and genus flavivirus. It predominantly infects the children under the age of 10 years and the case fatality rate can stretch out as high as 30%. Pigs act as reservoir and amplifying intermediate host for JEV. Recent report suggested longer persistence of JEV in tonsil than in circulation of experimentally infected pigs. The current investigation was conducted to understand the prevalence and molecular epidemiology of JEV infection in pigs in three different geographical sites in India (Odisha, Assam and Manipur). Serum samples were tested by ELISA and RT-PCR for detection of JEV, while only RT-PCR was done in case of tonsils tissues collected from pigs slaughtered in abattoir. Prevalence of JEV was highest in Manipur (25.45% in serum and 10.08% in tonsil) but lower in Assam (3.75% in serum and 0% in tonsils) and Odisha (1.49% in serum and 3.7% in tonsils). The percentage of sero-positivity was found to be 3.75% of IgM and 9.9% of IgG in Assam and Odisha respectively. Genotype III (GIII) of JEV was the dominant genotype and sporadic mutations of S83G, H76P, E78Q, C55S, and S64W along with two consistent mutations V46S and V51I were observed in all the GIII strains. Analysis of the E gene sequence revealed a single mutation, S118N in the GI strain. Older pigs (above 7 months) were found to be infected relatively more (8.6%) than younger pigs (age group 3-7 months). In conclusion, the high JE virus infection rate of pig in the current locations suggests the need for continuous surveillance of this virus in pigs which will ultimately help to adopt an effective control strategy to prevent the spread of JE infection to human.\n\nAuthor summaryJapanese encephalitis is one of the contributing factors in acute encephalitis syndrome cases reported across India as well as Asia. Primarily young naive human population are affected with JEV. The death rate can be as high as 30% and in about 30%-50% surviving population paralysis, brain damage or other serious permanent sequelae may be observed. The viral load gets amplified in pigs and thus plays a crucial role in transmitting the infection in human communities living in close proximity to pig dwelling. The current study was conducted to demonstrate prevalence of JEV in pig population of three geographical regions of India viz. the States of Odisha, Assam and Manipur that have reported JE outbreaks in human population. The current study demonstrates that the rate of infection is 3.28% among pigs in Manipur followed by Assam and Odisha. GIII was found to be the most predominant JEV genotype, while only one GI genotype strain was detected from Odisha region. These findings suggested the need of continuous surveillance of this virus in pigs and proper implementation of human and animal vaccination programme to control the infection.

microbiology↗