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Objective: Japanese encephalitis (JE) is a debilitating disease caused by infection with the JE virus (JEV; family: Flaviviridae), which leaves neurological sequelae in survivors but more often leads to mortality. Neurodegeneration caused by inflammation is the primary pathology behind the clinical manifestation of encephalitis caused by JEV. Bacillus Calmette-Guérin (BCG) has been used in immunoprophylaxis for tuberculosis and in the adjuvant therapy of many malignancies, and has exhibited neuroprotective activities in experimental models of Parkinson and Alzheimer disease. This study aimed at assessing the neuroprotective role of BCG in a murine model of JE. Methods: Suckling mice were inoculated with 10⁶ CFU of BCG and at 18 days postinoculation were challenged with 100 LD₅₀ of JEV. PBS-inoculated mice were used as controls. Mice were sacrificed on days 2, 4, 6, and 8. Brain tissue was homogenized for RNA extraction. One-step real-time RT-PCR was performed to assess the relative gene expressions of TNF-α, IL-6, and iNOS. Results: The BCG-inoculated (BCG+JEV) group exhibited a significant delay in the presentation of neuropathological symptoms, longer survival, and a downregulation in the expression of TNF-α, IL-6, and iNOS on days 2, 4, and 6 post-JEV challenge compared to the JEV group. Conclusion: These findings indicate that the administration of BCG offers neuroprotection in the murine model of JE. BCG should therefore be further investigated as an adjuvant in the management of JE. BCG is an accepted vaccine for tuberculosis in many countries that are endemic for JEV. This approach may have a significant impact on the public health burden in these countries.

Objective:The soxhlet and cold extracts of Datura metel Linn. were evaluated for in vitro antirabies activity.Materials and Methods:Soxhlet and cold extraction method were used to extract Datura (fruit and seed) extracts. In vitro cytotoxicity assay was performed by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide assay. Based on the CC50 range, the in vitro antirabies activity of the extracts was screened by rapid fluorescent focus inhibition test and molecular method.Results:The Datura (fruit and seed) extracts were not cytotoxic below 5 mg/ml (CC50). Titer of 10−4 rabies virus challenge virus standard (RV CVS) (1 50% tissue culture infective dose [1 TCID50]) was obtained by RFFT method and the challenge dose of 10 TCID50 was used for antirabies assay. Datura fruit and seed (soxhlet and cold) extracts showed 50% inhibition of RV CVS at 2.5 mg/ml and 1.25 mg/ml (inhibitory concentration 50% [IC50]), respectively. The tested extracts showed selectivity index (CC50/IC50) ranging from 2 to 4. The viral RNA was extracted and real-time reverse transcription-polymerase chain reaction was performed which also revealed a 2-fold reduction of viral load at 1.25 mg/ml of the Datura seed (soxhlet methanolic and cold aqueous) extracts.Conclusion:To the best of our knowledge, this is the first study of in vitro antiviral activity of D. metel Linn. against rabies virus. Datura seed extracts have a potential in vitro antirabies activity and, in future, can be further screened for in vivo activity against rabies virus in murine model.SUMMARY In the present study, Datura metel. Linn showed and in-vitro anti rabies activity in Vero cell line which was determined by RFFIT method and PCR method

A total of 100 blood and 18 urine samples of rodents and suspected dogs were collected from Mumbai, India during 2006-2008. In order to determine the role of animals in transmission of the disease to humans, all the samples were screened retrospectively by real-time polymerase chain reaction for leptospiral DNA and antibodies were detected using microscopic agglutination test. Leptopsiral DNA was detected from two blood and five urine samples from rodents. Of a total of 71 rodent and dog samples investigated for anti-Leptospira antibodies, 14 (19.7%) were positive. Pyrogenes was the predominant serovar found in 100.0% (7/7) and 85.7% (6/7) from suspected canine cases and rodents, respectively; followed by Icterohemorrhagiae, which was found in one rodent sample 14.28% (1/7). The study proves that there is high prevalence of leptospirosis in rodents and dogs in this region, which proves possible role of these animals in transmission of leptospires to humans. Hence it is imperative to necessary control measures to prevent human leptospirosis.

Rabies is an acute viral infection that causes encephalomyelitis in almost all warm blooded animals and is invariably fatal once the clinical signs appear. The present study was carried out to assess the effect of recombinant human interferon alpha (rhIFN a-2A) treatment on the survival of rabies infected mice and its correlation with cytokines expression. The gene expression of TNF-a and IL-6 was measured by SYBR Green Real Time PCR for two groups-''Pre-exposure'' (mice were inoculated with rhIFN a-2A prior to rabies infection) and ''Post-exposure'' (mice were inoculated with rhIFN a-2A post rabies virus infection). Delayed mortality was observed in interferon treated infected groups. In addition, statistically significant decrease (P \ 0.0001) in the expression of TNF-a and IL-6 was observed, both in the pre-exposure and post-exposure groups. These findings indicate that modulation of cytokine secretion using exogenous biologicals such as rhIFN may offer novel therapeutic approaches to treat diseases such as rabies.