Why Does It Take More Than a Week Before a Mosquito

question 34

Multiple Choice

Why does it take more than a week before a mosquito that has just become infected with yellow fever virus can transmit the disease?

• A) The virus must replicate in the gut of the mosquito before it can reach high enough numbers for transmission to a new human.
• B) Mosquitoes only feed once a week, which limits their ability to transmit the disease rapidly.
• C) Mosquitoes that acquire yellow fever virus become ill for a week thereafter. They have to recover before they can feed again and transmit the virus to the next host.
• D) The virus multiplies in the gut of the mosquito, but then needs to migrate to the mouth of the insect in order to infect a new human being after a new bite. This migration takes time.
• E) The mosquito actually transmits the virus almost immediately. It takes a week for the virus to multiply in the gut of the host before it causes any ill effects in that host.

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Definitions:

Collective Agreements

Contracts between employers and trade unions outlining terms of employment, working conditions, and employee rights.

Working Conditions

Facts about the situation in which the worker acts; includes physical environment, hours, hazards, travel requirements, and so on, associated with a job.

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An extensive range of employee benefits, including health insurance, retirement plans, and other perks, provided by an employer.

Unionized Employees

Workers who are members of a union, which is an organization that represents their interests in negotiations with employers.