Influenza Pandemics Occur Cyclically Because

question 47

Multiple Choice

Influenza pandemics occur cyclically because

• A) less than 100% of the population is immunized.
• B) new strains emerge due to reassortment between bird, swine, and human variants.
• C) the vector is seasonal.
• D) there are environmental reservoirs that release the virus during particular seasons.

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Definitions:

Attention

The mental activity of focusing intently on a single element of the surroundings while disregarding other aspects.

Circadian Cycle

The internal biological clock that regulates approximately 24-hour cycles of biological processes in organisms.

Psychological Problems

Issues or disorders that affect a person's mental health and wellbeing, ranging from anxiety and depression to schizophrenia.

Latent Content

In psychoanalytic theory, the underlying meaning or significance hidden in dreams, distinct from the dreams' manifest content.