Unenveloped

Unenveloped refers to a characteristic of certain viruses. Viruses are infectious agents that replicate inside the living cells of other organisms. Many viruses are composed of genetic material, such as DNA or RNA, enclosed within a protein coat called a capsid. Some viruses also have an outer lipid layer derived from the host cell membrane, known as an envelope. Viruses that lack this outer envelope are described as unenveloped, naked, or non-enveloped.

The presence or absence of an envelope has significant implications for a virus's structure, survival, and transmission. Unenveloped viruses typically have a more rigid structure due to their protein capsid being the outermost layer. This structure can make them more resistant to environmental factors such as heat, detergents, and drying, which can easily damage the lipid envelope of enveloped viruses. Consequently, unenveloped viruses can often survive for longer periods on surfaces and are frequently transmitted through fecal-oral routes, where they may encounter harsher conditions. Examples of unenveloped viruses include poliovirus, norovirus, and adenovirus. The differences in structure and survival mechanisms between enveloped and unenveloped viruses are crucial for understanding viral pathogenesis and developing effective control strategies.