Overview of Diseases and Pathogens

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Questions and Answers

Why is herd immunity considered important for community health?

It protects individuals who cannot be vaccinated. (correct)

It eliminates all bacterial infections.

It ensures all individuals are vaccinated.

It allows for lower vaccination rates among the general population.

What is a major consequence of overusing antibiotics?

It leads to the effective treatment of viral infections.

It causes the development of antibiotic resistance. (correct)

It prevents bacterial infections from spreading.

It creates stronger antibiotics that can treat all infections.

Which of the following statements about antibiotics is true?

Antibiotics can treat both bacterial and viral infections.

Penicillin has no impact on human health.

Antibiotics are completely safe with no side effects.

Penicillin was discovered in 1928 by Alexander Fleming. (correct)

How can individuals help reduce antibiotic resistance?

Complete the full prescription as directed. Signup and view all the answers

Which of the following statements regarding antibiotic resistance is correct?

Antibiotic resistance is a leading threat to human health. Signup and view all the answers

What is the primary method through which fungi reproduce?

By fragmentation or budding Signup and view all the answers

Which infection is NOT caused by fungi?

COVID-19 Signup and view all the answers

Why are viruses not considered living organisms?

They cannot reproduce without a host cell Signup and view all the answers

Which of the following is a common feature of all viruses?

A protective protein shell or capsid Signup and view all the answers

What is the first step in the reproductive cycle of a virus?

The virus injects its DNA into the host cell Signup and view all the answers

Which of the following diseases is a viral infection?

Rubella Signup and view all the answers

What public health strategy helps authorities assess risks during an outbreak?

Wastewater testing Signup and view all the answers

Which of the following is NOT a strategy to stop the spread of diseases?

Promotion of large social gatherings Signup and view all the answers

Which disease is classified as an acquired non-communicable disease?

Osteoporosis Signup and view all the answers

Which of the following diseases is caused by a protozoan pathogen?

Giardiasis Signup and view all the answers

What type of disease is cancer primarily classified as?

Acquired Non-communicable Disease Signup and view all the answers

Which of the following is a characteristic of congenital diseases?

Can be inherited or arise from environmental factors during pregnancy Signup and view all the answers

Which disease is transmitted through environmental factors rather than pathogens?

Schizophrenia Signup and view all the answers

What type of pathogen is responsible for causing thrush?

Fungi Signup and view all the answers

Which of the following options is NOT a type of non-infectious disease?

Cystic Fibrosis Signup and view all the answers

Which type of non-communicable disease is associated with lifestyle factors?

Cancer Signup and view all the answers

What is the primary function of the body's first line of defence?

To stop pathogens from entering the body. Signup and view all the answers

Which of the following is NOT considered a physical barrier in the first line of defence?

Saliva Signup and view all the answers

What role do Mast Cells play in the second line of defence?

They release histamine to increase blood flow. Signup and view all the answers

Which statement accurately describes the second line of defence?

It involves immediate action without prior exposure to pathogens. Signup and view all the answers

During which phase does the body experience redness, swelling, heat, and pain?

The inflammatory response Signup and view all the answers

What is the primary role of fever in the immune response?

To create a hostile environment for pathogens Signup and view all the answers

What is the purpose of chemical barriers in the first line of defence?

To create an acidic environment to kill pathogens. Signup and view all the answers

Which of the following is an example of a biological barrier?

Good bacteria in the intestines Signup and view all the answers

Which of the following immune cells is NOT classified as a phagocyte?

T helper cells Signup and view all the answers

What happens during the incubation period after infection?

The pathogen multiplies and builds up toxins. Signup and view all the answers

What is a characteristic of the non-specific immune response?

It provides a rapid response to any invading pathogen Signup and view all the answers

What distinguishes the third line of defense from the first and second lines of defense?

It involves specialized white blood cells that target specific pathogens Signup and view all the answers

What is the function of memory B cells in the immune system?

To remember specific pathogens for quicker responses Signup and view all the answers

How does the immune system differentiate between 'self' and 'non-self'?

Using the unique shapes called antigens present on pathogens Signup and view all the answers

Which statement about B cells is true?

B cells are responsible for memory storage of pathogens Signup and view all the answers

What role do phagocytes play in the immune response?

They ingest and absorb invading pathogens Signup and view all the answers

Study Notes

Diseases

Diseases can be either congenital, acquired, or non-communicable/non-infectious.
Congenital diseases are present at birth and are caused by genetic factors.
Acquired diseases are developed after birth and can be caused by environmental factors, lifestyle choices, or infections.
Non-communicable/non-infectious diseases are not caused by pathogens but can be caused by genetic factors, lifestyle choices, or environmental toxins.

Pathogens

Pathogens are infectious agents that can cause disease.
There are many types of pathogens, including bacteria, viruses, fungi, protozoa, and prions.
Pathogens cause illnesses by invading the body and disrupting normal functions.

Fungi

Fungi are found in air, soil, water, and on plants.
They reproduce asexually through fragmentation, budding, or spore production.
Fungal infections commonly start in the lungs or on the skin.
Some examples of fungal infections include thrush, ringworm, and athlete's foot.

Viruses

Viruses are tiny, infectious particles that cannot reproduce on their own and require a host cell to replicate.
They "commandeer" host cells to produce more viruses, effectively reprogramming them.
Viruses are not considered living organisms because they cannot reproduce independently.
Antibiotics are ineffective against viruses.

Viral Structure and Reproduction

Viruses have a protective protein shell called a capsid.
The capsid encloses the virus's genetic material (DNA).
The capsid allows the virus to attach to and infect host cells.
Viral reproduction involves several steps: the virus injects its DNA into the host cell, the viral DNA gets replicated by the host cell's organelles, and thousands of new viruses are produced, eventually bursting the host cell and releasing them to infect other cells.

Examples of Viral Diseases

Common viral diseases include polio, rabies, hepatitis, rubella, and COVID-19.

Preventing Disease Spread

Strategies used to prevent disease spread vary depending on the pathogen and its mode of transmission.
These include vaccination programs, risk assessment strategies like contact tracing and testing, movement restrictions like lockdowns, quarantines, and isolation, measures to reduce spread like masks, social distancing, and hand washing, treatment with antibiotics (for bacterial infections only) and antivirals, and social strategies such as public awareness campaigns, funding for vaccine research, public compliance and enforcement, and international cooperation.

The Immune System

The human body has three lines of defense against disease.

First Line of Defense

The first line of defense is a passive immune system and acts as a barrier to pathogens.
This defense includes physical barriers (skin, cilia, nasal hairs), chemical barriers (saliva, tears, stomach acid), and biological barriers (good bacteria on skin and in the intestine).

Second Line of Defense

The second line of defense is activated after pathogens have entered the body.
It includes inflammation, fever, blood clotting, and phagocytosis.
Inflammation is characterized by redness, swelling, heat, and pain.
Fever increases body temperature, making it harder for pathogens to survive.
Blood clots prevent pathogens from entering the bloodstream.
Phagocytes, like macrophages, neutrophils, and monocytes, are immune cells that engulf and digest pathogens.

Third Line of Defense

The third line of defense is a specific and acquired immune response.
Lymphocytes, a type of white blood cell, are the key players in the third line of defense.
There are two main types of lymphocytes: T cells and B cells.
The third line of defense is specific because it targets specific pathogens.
The third line of defense is acquired because it develops throughout an individual's life, based on exposure to pathogens.
Immunological memory, provided by memory B cells, allows the body to remember and mount a faster and stronger response to previously encountered pathogens.
Vaccines work by harnessing the body's immunological memory to provide immunity against specific diseases.

Antigens and Antibodies

Pathogens contain foreign chemicals called antigens, which are recognized by the immune system as "non-self."
The immune system distinguishes between "self" and "non-self" using antigens.
B cells produce antibodies, which bind to specific antigens on pathogens and neutralize them.

T Cell Function

T cells are a type of lymphocyte that directly attack and destroy infected host cells.
T cells identify infected cells by recognizing foreign antigens on their surface.

Herd Immunity

Herd immunity occurs when a significant proportion of the population is immune to a disease, making it difficult for the disease to spread.
Vaccination is a key part of achieving herd immunity.

Antibiotics

Antibiotics are drugs used to treat bacterial infections.
They are not effective against viruses.
Antibiotic resistance is a major public health concern.

Antibiotic Resistance

Antibiotic overuse is a major cause of antibiotic resistance.
Overuse of antibiotics creates superbugs, bacterial strains that are resistant to certain antibiotics.
Antibiotic resistance makes bacterial infections more difficult to treat.
The World Health Organization has declared antibiotic resistance a major global health threat.

Measures to Reduce Antibiotic Resistance

Take antibiotics only for bacterial infections.
Complete the full course of antibiotics as prescribed, even if you feel better.
Avoid sharing antibiotics with others or using leftover prescriptions.

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Description

This quiz covers the fundamentals of diseases, including congenital, acquired, and non-communicable types. It also explores pathogens, their role in causing infections, and details on fungi as a specific pathogen. Test your knowledge on how these elements contribute to human health.