GCSE Biology Revision "Communicable and Non-Communicable Disease"

Introduction to Diseases

• Key Concepts:

  • Diseases can be categorized into communicable and non-communicable.

  • Communicable diseases can be spread from person to person, while non-communicable diseases cannot.

Communicable Diseases

• Definition: Diseases that can be spread from person to person.

• Example: Measles

  • Caused by pathogens (bacteria or viruses).

• Impact: Major causes of ill health; contributes to physical and mental health issues.

Non-communicable Diseases

• Definition: Diseases that cannot be passed from person to person.

• Example: Coronary heart disease

  • Often chronic and linked to lifestyle factors.

• Impact: Also major contributors to health issues, typically stemming from internal body processes rather than external pathogens.

Causes of Ill Health

• Definition of Health: State of physical and mental well-being.

• Multiple factors lead to ill health, including:

  • Communicable Diseases: Measles, tuberculosis (TB), etc.

  • Non-communicable Diseases: Coronary heart disease, arthritis, etc.

  • Lifestyle Factors: Poor diet, high stress levels, exposure to harmful chemicals.

Interaction Between Different Types of Diseases

• Example 1: Tuberculosis and HIV

  • TB is communicable; fatal in severe cases.

  • Those with defective immune systems (like HIV patients) are more susceptible to TB.

  • In most people, the immune system can fight off TB; however, some people have a defective immune system, for example, people with HIV.

    People with a defective immune system are much more likely to suffer from infectious diseases.

    So, you can see that one disease, in this case, HIV, increases the risk of contracting a different disease, in this case, TB.

• Example 2: Human Papilloma Virus (HPV)

  • HPV is common; can lead to cervical cancer in some.

  • HPV is extremely common, and in most people, it's essentially harmless. However, in some people, HPV can cause cervical cancer. Most cervical cancers are caused by the HPV infecting the cells of the cervix.

    So, infection with one disease, in this case, HPV, causes another disease, in this case, cervical cancer.

Disease Triggering and Mental Health

• Allergies and Asthma

  • Certain physical diseases can lead to allergies; immune response can create long-term issues like asthma or dermatitis.

  • sometimes a disease can be triggered by the immune system, and a good example of this is allergies, such as certain cases of asthma or dermatitis.

    In these cases, the body is infected with a pathogen which the immune system fights off, but then the person is left with an allergy.

• Physical Illness Triggering Mental Health Issues

  • Example: Arthritis causes chronic pain and mobility issues, which can lead to depression due to isolation and inability to engage in normal activities.