Flu and cold season offers excellent examples of physiologic reflexes to ward off illness. one problem is that an effective mechanical defense for one person can complete a link in the chain of infection for someone else. to which link is the above referring?

Method of Transmission

Explanation:

Method of Transmission involves the transfer of a transmissible disease pathogen from  an infected host person or group to a specific person or group,  irrespective of whether the other person was earlier infected.

Types of Method of Transmission include:

Direct Physical Contact - Contacting an infected person .Indirect Physical Contact - being in contact with an infected surface or object .Droplet Contact - coughing or wheezing on a person Airborne Transmission - when bacteria can stay in the atmosphere for long .Fecal-Oral Transmission - Due to absence of sanitation and hygiene,  generally from unwashed hands,  contaminated food or water sources.

Major sources of stress, such as a death or divorce, problems in family relationships, job loss, school, and substance abuse, can trigger or aggravate some mental disorders in some people. but not everyone who goes through those things develops a mental illness

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