VIRUSES-TYPES

  • Virus are microorganisms that infect plants, animals, humans, and bacteria. They have genetic material, either DNA or RNA, enclosed in a protective shell called capsid. A few of them having an envelope that prevents self-replication without hosts, so they are just like parasites visibly smaller than cells by 100 to 1000 times. 
  • Spikes exist on some viruses and examples are SARS-CoV-2 (Corona virus) and HIV.
  • Types of viruses include influenza viruses, human herpesviruses, coronavirus, human papillomaviruses, enteroviruses, flaviviruses, and orthopoxviruses. 
  • The other unique ones are retroviruses and oncoviruses.
  •  Influenza viruses cause flu. 
  • Human herpesviruses cause diseases such as herpes, chickenpox, shingles, Epstein-Barr virus, cytomegalovirus.
  • Coronaviruses are a subfamily of viruses causing COVID-19, which includes the SARS-CoV-2 virus. 
  • Human papillomavirus, HPV, causes warts and some cancer. 
  • The enteroviruses attack the intestinal tract.
  • Flaviviruses cause the Zika, West Nile, Dengue fever, and yellow fever.
  •  Orthopoxviruses are responsible for blistering rashes, while hepatitis viruses attack the organ liver. 
  • Retroviruses make use of special proteins to make DNA, for example, HIV and human T-lymphotropic virus 1 (HTLV-1)
  •  Oncoviruses can cause cancer. HPV, Epstein-Barr, HIV, Hepatitis B and C, and HHV-8 have been specifically related to some cancers. 
  • The replication of satellite viruses takes place necessarily because of the helper viruses. They are mostly found in plants.
  •  One under study is the bacteriophage, (bacteria that infect viruses) therapy that could be a possible line of treatment against bacterial diseases that do not respond to antibiotics. 

SARS-CoV-2 (Courtesy: Google)

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