(noun. /VEER-you-lense/)
by Nicole Gadda
What does it mean?
Virulence is the severity of the damage a microorganism (like bacteria, viruses, and fungi) can cause to a host. Some viruses, like Ebola, are highly virulent and can cause life-threatening disease. Other viruses, like the common cold, are less virulent and may result in only a few days of congestion and a sore throat. But the term ‘virulence’ doesn’t always apply to viruses. We know bacteria can make us sick, as well. For example, Staphylococcus aureus is one of the millions of bacteria that compose our skin microbiome. In healthy individuals, S. aureus typically doesn’t cause infections. However, different strains of S. aureus, like methicillin-resistant S. aureus (MRSA), are more virulent due to having high antibiotic resistance. MRSA infections can affect the skin, blood, and bones, causing sepsis and other life-threatening conditions.
How do I use it in a sentence?
Scientists have been studying the differences in virulence of the SARS-CoV-2 variants. Studies have shown the Beta variant is one of the most virulent variants of SARS-CoV-2, increasing the number of hospitalizations and deaths. In comparison, the Omicron variant is less virulent and causes less severe infection.
Etymology
Virulence comes from the Latin word virulentus, meaning “full of poison.”
Related terms
Pathogen
Infection
Virulence factors
Fields of study in which this word is commonly used
Microbiology
Infectious disease
Public health
