Demographic transitionIn demography, demographic transition is a phenomenon and theory which refers to the historical shift from high birth rates and high death rates in societies with minimal technology, education (especially of women) and economic development, to low birth rates and low death rates in societies with advanced technology, education and economic development, as well as the stages between these two scenarios.
Virus latencyVirus latency (or viral latency) is the ability of a pathogenic virus to lie dormant (latent) within a cell, denoted as the lysogenic part of the viral life cycle. A latent viral infection is a type of persistent viral infection which is distinguished from a chronic viral infection. Latency is the phase in certain viruses' life cycles in which, after initial infection, proliferation of virus particles ceases. However, the viral genome is not eradicated.
InfantAn infant or baby is the very young offspring of human beings. Infant (from the Latin word infans, meaning 'baby' or 'child') is a formal or specialised synonym for the common term baby. The terms may also be used to refer to juveniles of other organisms. A newborn is, in colloquial use, an infant who is only hours, days, or up to one month old. In medical contexts, a newborn or neonate (from Latin, neonatus, newborn) is an infant in the first 28 days after birth; the term applies to premature, full term, and postmature infants.
World populationIn demographics, the world population is the total number of humans currently living. It was estimated by the United Nations to have exceeded eight billion in mid-November 2022. It took over 200,000 years of human prehistory and history for the human population to reach one billion and only 219 years more to reach 8 billion. The human population has experienced continuous growth following the Great Famine of 1315–1317 and the end of the Black Death in 1350, when it was nearly 370,000,000.
Viral loadViral load, also known as viral burden, is a numerical expression of the quantity of virus in a given volume of fluid, including biological and environmental specimens. It is not to be confused with viral titre or viral titer, which depends on the assay. When an assay for measuring the infective virus particle is done (Plaque assay, Focus assay), viral titre often refers to the concentration of infectious viral particles, which is different from the total viral particles. Viral load is measured using body fluids Sputum and blood plasma.
SuperinfectionA superinfection is a second infection superimposed on an earlier one, especially by a different microbial agent of exogenous or endogenous origin, that is resistant to the treatment being used against the first infection. Examples of this in bacteriology are the overgrowth of endogenous Clostridium difficile that occurs following treatment with a broad-spectrum antibiotic, and pneumonia or sepsis from Pseudomonas aeruginosa in some immunocompromised patients. In virology, the definition is slightly different.
Viral phenomenonViral phenomena or viral sensation are objects or patterns that are able to replicate themselves or convert other objects into copies of themselves when these objects are exposed to them. Analogous to the way in which viruses propagate, the term viral pertains to a video, image, or written content spreading to numerous online users within a short time period. This concept has become a common way to describe how thoughts, information, and trends move into and through a human population.
Respiratory diseaseRespiratory diseases, or lung diseases, are pathological conditions affecting the organs and tissues that make gas exchange difficult in air-breathing animals. They include conditions of the respiratory tract including the trachea, bronchi, bronchioles, alveoli, pleurae, pleural cavity, the nerves and muscles of respiration. Respiratory diseases range from mild and self-limiting, such as the common cold, influenza, and pharyngitis to life-threatening diseases such as bacterial pneumonia, pulmonary embolism, tuberculosis, acute asthma, lung cancer, and severe acute respiratory syndromes, such as COVID-19.
EvolvabilityEvolvability is defined as the capacity of a system for adaptive evolution. Evolvability is the ability of a population of organisms to not merely generate genetic diversity, but to generate adaptive genetic diversity, and thereby evolve through natural selection. In order for a biological organism to evolve by natural selection, there must be a certain minimum probability that new, heritable variants are beneficial. Random mutations, unless they occur in DNA sequences with no function, are expected to be mostly detrimental.
Viral marketingViral marketing is a business strategy that uses existing social networks to promote a product mainly on various social media platforms. Its name refers to how consumers spread information about a product with other people, much in the same way that a virus spreads from one person to another. It can be delivered by word of mouth, or enhanced by the network effects of the Internet and mobile networks. The concept is often misused or misunderstood, as people apply it to any successful enough story without taking into account the word "viral".
