Characteristics of Disease Agents

What does the term 'infectivity' refer to in the context of agents of disease?

Ability to gain access and adapt to the human host

How is 'virulence' defined when discussing agents of disease?

Severity of the reaction produced by the agent

What is the difference between direct and indirect transmission of infectious agents?

Direct transmission involves immediate transfer to a receptive portal of entry, while indirect transmission involves a vehicle or vector.

What are the two types of indirect transmission of diseases?

Vehicle-borne and Vector-borne Signup and view all the answers

How are airborne diseases transmitted?

Through dissemination of microbial aerosols to a suitable portal of entry, typically the respiratory tract Signup and view all the answers

What are some host factors that can influence disease?

Age, Sex, Race Signup and view all the answers

Define epidemiology.

Study the occurrence and distribution of diseases as well as distribution of determinants of health state or events in specified population and the application of this study to control health problems. Signup and view all the answers

What did C.E.A. Winslow call epidemiology?

The diagnostic discipline of public health. Signup and view all the answers

What does epidemiology study in terms of diseases?

The behavior of disease in the community rather than in individual patients, including the study of reservoirs and sources of human disease. Signup and view all the answers

What does epidemiology do when they detect an epidemic?

They ask who, when, and where questions. Signup and view all the answers

What is the significance of notifiable disease surveillance?

It is surveillance made by the government to detect diseases before many people start dying. Signup and view all the answers

What is the etymology of the term 'epidemic'?

Derived from the Greek word 'upon the people', meaning leading the people. Signup and view all the answers

What is the ultimate goal of epidemiology?

To control and prevent the spread of disease Signup and view all the answers

What are the two main areas of investigation in epidemiology?

<ol> <li>Describing the distribution of health status based on various factors. 2. Analyzing patterns of disease distribution in terms of causal factors.</li> </ol> Signup and view all the answers

What are the three factors studied in the epidemiology of any disease or event?

Agent, Host, Environment Signup and view all the answers

What are some of the uses of epidemiology?

<ol> <li>Studying the history of the health population. 2. Diagnosing the health of the community. 3. Analyzing the work of health services for improvement. 4. Estimating disease risks. 5. Describing the clinical features of chronic diseases. 6. Investigating the causes of health and disease.</li> </ol> Signup and view all the answers

What is an agent in the epidemiology of disease?

Any element, substance, or force that can initiate or perpetuate a disease process. Signup and view all the answers

What types of agents can contribute to disease processes?

Living or non-living things Signup and view all the answers

What is the purpose of strict isolation?

To prevent transmission of highly contagious or virulent infections. Signup and view all the answers

When is respiratory isolation used?

To prevent transmission of infectious diseases through the air over short distances. Signup and view all the answers

What is the purpose of Enteric Precautions?

To prevent infections transmitted by direct or indirect contact with feces or purulent material. Signup and view all the answers

In which category of isolation are patients with pulmonary tuberculosis placed?

Tuberculosis isolation (AFB isolation) Signup and view all the answers

What is the purpose of Drainage/secretion Precautions?

To prevent infections transmitted by direct or indirect contact with purulent material or drainage from an infected body site. Signup and view all the answers

Why are Blood/body fluid Precautions implemented?

To prevent infections transmitted by direct or indirect contact with infected blood or body fluids. Signup and view all the answers

What is the purpose of quarantine?

To prevent disease transmission during the incubation period of infection. Signup and view all the answers

What is the difference between Absolute Quarantine and Modified Quarantine?

Absolute Quarantine limits the movement of those exposed for the longest incubation period, while Modified Quarantine selectively limits the freedom of movement of contacts. Signup and view all the answers

What are the two main phases in the pathogenesis of a disease?

Pre-pathogenesis and Pathogenesis. Signup and view all the answers

List three requirements for the successful invasion of a host by an infectious agent.

Suitable reservoirs, a susceptible host, and a satisfactory portal of entry. Signup and view all the answers

What is the period of pre-pathogenesis of a disease?

The phase before the agent affects humans. Signup and view all the answers

How many categories of quarantine are mentioned in the text?

Two categories: Absolute or Complete Quarantine, Modified Quarantine. Signup and view all the answers