Context:
Metagenome sequencing is transforming pathogen surveillance nowadays.
Key Points:
- The identification of SARS-CoV-2 as the causative agent of COVID-19 came from the application of unbiased genome sequencing technologies to infected patient samples.
- Instead of time-consuming microbiology route scientists directly subjected to genome-sequencing and bio-informatic analysis that helped the scientists quickly identify the virus. This new approach is called “metagenomics”.
- GISAID (Global Initiative On Sharing All Influenza Data) – a repository with high-throughput genome surveillance of SARS-Co-V-2 genome-sequence data.
- ‘High-throughput’ refers to sequencing techniques that can parse large quantities of DNA at the same time, including a whole genome at once.
Metagenomics is the study of the structure and function of entire nucleotide sequences isolated and analyzed from all the organisms (typically microbes) in a bulk sample.
Genome sequencing:
- It is a technique that reads and interprets genetic information found within DNA or RNA.
- In case of DNA, deciphering the order of DNA nucleotides or bases in a genome i.e. the order of Adenine (A), Cytosine (C), Guanine (G) and Thymine (T) that make up an organism’s DNA.
- Applications –
- Greater understanding of evolution of Biology
- Identification of genomic causes of rare diseases, neurodegenerative diseases, cancer etc.
- Identifying genetic mutation in virus
A genome is an organism’s complete set of DNA which includes all chromosomes which houses DNA and genes. A human genome contains about 3 million base pairs.
Diseases related with the study:
- Lassa fever –
- A viral haemorrhagic fever
- Caused by – Lassa virus
- Endemic to West African countries
- Pegivirus C – Common co-infection in patients with Lassa fever
- mpox virus
- Avian influenza or bird flu
- Other Seasonal pathogenic viruses – Zika, Dengue, lumpy skin disease, drug-resistant tuberculosis etc.
About mpox (Monkeypox):
- A zoonotic disease
- Caused by – virus
- 1st discovered in 1958.
- Occurrence area – Tropical rainforests of Central and West Africa.
- Animal-to-human transmission– Direct contact with the blood, bodily fluids, or cutaneous or mucosal lesions of infected animals.
- WHO recently recommended new name “mpox” for monkeypox disease.
- No specific treatment or vaccine available [Smallpox vaccine gives protection]
About Avian Influenza or Bird flu:
- A contagious viral disease
- Can spread from one bird to other birds and animals.
- Caused by – Influenza Type A viruses (generally affect poultry birds – chickens and turkeys)
- Classification based on origin host:
- Avian influenza (H5N1, H9N2)
- Swine influenza (H1N1 and H3N2)
- Also affects humans through direct contact.
About Lumpy Skin Disease (LSD):
- A vector-borne pox disease (Not a zoonotic disease)
- Aim – To protect cattle against LSD virus.
- Caused by – virus
- Infects cattle and water buffalo
- Vectors – Blood-feeding insects.
- Endemic in most African countries
- Had spread in Middle East, Southeast Europe and West and Central Asia.
- 1st time in India – Odisha (2019)
- Vaccine – Lumpi-ProVacInd vaccine
- A homologous, live attenuated vaccine developed by Indian Council of Agricultural Research (ICAR).
Source: The Hindu
Previous Year Questions
‘Aerial metagenomics’ best refers to which one of the following situations?
[UPSC Civil Services Exam – 2023 Prelims]
(a) Collecting DNA samples from air in a habitat at one go
(b) Understanding the genetic makeup of avian species of a habitat
(c) Using air-bome devices to collect blood samples from moving animals
(d) Sending drones to inaccessible areas to collect plant and animal samples from land surfaces and water bodies
H1N1 virus is sometimes mentioned in the news with reference to which one of the following diseases?
[UPSC Civil Services Exam – 2015 Prelims]
(a) AIDS
(b) Bird flu
(c) Dengue
(d) Swine flu
