Context:
The Gujarat Biotechnology Research Centre (GBRC) in Gandhinagar has achieved a significant milestone by successfully publishing the first fully mapped genome of the Chandipura Vesiculovirus (CHPV). This virus is known for causing encephalitis, a condition characterized by brain swelling. The mapping comes in the wake of a substantial outbreak that affected numerous individuals in Gujarat during July and August, highlighting the critical importance of this research in understanding and combating the virus effectively.
Relevance:
GS II: Health
Dimensions of the Article:
- Genome Mapping
- Specific Findings from GBRC’s Genome Mapping of CHPV
- Chandipura Virus
Genome Mapping
- Definition and Process: Genome mapping involves identifying gene locations and key sequences within a genome, providing insights into the origins, mutations, and potential dangers of viruses.
- Types of Genome Maps:
- Genetic Maps: Display gene positions based on recombination frequencies.
- Physical Maps: Indicate exact gene positions using DNA base pairs.
Importance of Genome Mapping
- Medical Advancements: Facilitates the early detection of genetic diseases, aids in creating personalized medical treatments, and enhances genetic counseling effectiveness.
- Agricultural Benefits: Helps in breeding programs by identifying traits that enhance yield, disease resistance, and quality in crops and livestock.
- Virus Research: Essential for developing vaccines by analyzing the genomic structures of pathogens, such as those causing COVID-19 and Chandipura virus (CHPV).
- Evolutionary Biology: Provides insights into the evolutionary relationships among species by analyzing genetic sequences.
Challenges in Genome Mapping
- Complexity in Larger Genomes: Genomes of plants and animals can be complex and repetitive, complicating precise mapping efforts.
- Privacy and Ethical Concerns: Issues arise over the use and access to genetic information.
- Resource Intensity: Requires significant financial and technological investment, with ongoing challenges in interpreting the relevance of various genes and sequences.
Specific Findings from GBRC’s Genome Mapping of CHPV
- Genetic Stability: The CHPV strain from a recent outbreak in Gujarat shows minimal genetic variation from the 2012 strain, except for a single mutation in the glycoprotein-B gene, crucial for the virus’s interaction with human cell receptors.
- Impact Despite Low Viral Load: Despite low viral load indicated by high Cycle Threshold values in RT-PCR tests, the virus caused severe symptoms.
- Indigenous Strain Confirmation: Sequencing confirms that the current strain is similar to those identified in previous outbreaks within India (2003-04, 2007), distinct from strains outside India, indicating no external introduction.
Chandipura Virus
- Nature of the Virus: Chandipura virus is an infectious agent known to cause Acute Encephalitis Syndrome (AES), which can lead to severe brain swelling and is potentially lethal.
- Symptoms and Impact: It manifests as fever, headache, and encephalitis, leading to severe neurological symptoms like convulsions, coma, and often death within days after the onset.
Transmission Vectors
- Virus Classification: The Chandipura virus is part of the Rhabdoviridae family, akin to the rabies virus.
- Vectors: The virus is transmitted to humans through bites from Phlebotomine sandflies and Phlebotomus papatasi, with Aedes aegypti mosquitoes also serving as carriers.
- Infection Mechanism: It resides in the salivary glands of these vectors and infects vertebrates via bites.
Progression and Clinical Presentation
- Infection Spread: Post-bite, the virus rapidly invades the central nervous system, causing encephalitis characterized by brain inflammation.
- Symptomatology: Initial symptoms include flu-like effects, progressing to more severe conditions such as altered mental status, seizures, respiratory issues, and bleeding tendencies.
- Disease Course: The progression is swift, typically resulting in fatality within 24-48 hours post-hospitalization.
Demographics and Epidemiology
- High-Risk Group: Mainly affects children under the age of 15.
- Seasonality: Peaks during monsoon seasons when sandfly populations increase, leading to more frequent outbreaks.
Historical Data and Epidemiological Patterns
- Discovery: Identified in 1965 during investigations for dengue and chikungunya in Maharashtra, India.
- Notable Outbreaks: Significant outbreaks were recorded in 2003-2004 in Maharashtra, northern Gujarat, and Andhra Pradesh, with over 300 child fatalities.
- Case Fatality Rates: Notably high fatality rates, with 78% during the Gujarat outbreak in 2004 and 55% in Andhra Pradesh in 2003.
- Endemic Areas: The virus remains endemic in central India, predominantly affecting rural, tribal, and peripheral regions where vector populations are dense.
-Source: Indian Express
