•

Updated Mar 20, 2026

•

1 page

Understanding Communicable Diseases

@uwu_fpjs

Communicable diseases are illnesses that can spread from person to... Show more

# Communicable diseases

A communicable disease is a disease that can be passed on person to person using
different methods. E.g. common col

Communicable Diseases and Their Causes

Ever wondered how you catch a cold? Communicable diseases pass from person to person through various routes. These illnesses can be caused by different types of pathogens that attack our bodies in unique ways.

Viruses are tiny invaders about 100,000 times smaller than bacteria. Unlike bacteria, all viruses are harmful. They invade your cells, multiply inside them, and eventually cause the cells to burst and die. This releases more viruses that attack other cells, continuing the destructive cycle. You often catch viral infections through the air when someone coughs, sneezes, or even talks.

Bacteria come in both helpful and harmful varieties. Good bacteria help maintain your health, treat sewage, and produce medicines and food. They're also vital decomposers in the environment. Harmful bacteria are pathogens that produce toxins as they divide through binary fission, damaging your cells directly. Bacterial infections like gonorrhoea spread through direct contact between people.

Health Alert: Gonorrhoea is a bacterial infection of the sexual organs. You can reduce your risk by avoiding contact with infected sex organs and using protection. If infected, antibiotics can treat the disease.

Diseases spread through three main routes: direct contact (through infected plants, sexual contact, cuts, or animal vectors), water (contaminated food or water entering through the digestive system), and air (breathing in pathogens expelled when people cough, sneeze, or talk).

We thought you’d never ask...

What is the Knowunity AI companion?

Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.

Where can I download the Knowunity app?

You can download the app from Google Play Store and Apple App Store.

Is Knowunity really free of charge?

That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.

Similar content

Facials 2

104

Criminology mind maps for biological, individualistic and learning theories of crime

971

Knowledge organizer of element 1 content

492

Success Factors in Hospitality

Explore the critical factors influencing the success of hospitality and catering providers. This summary covers key concepts such as market saturation, financial management, branding, and customer service, essential for understanding the dynamics of the industry. Ideal for WJEC Level 1/2 Hospitality & Catering students preparing for exams and coursework.

Food & Nutrition

Nutritional Science Essentials

Explore the key concepts of macronutrients and micronutrients, including proteins, fats, carbohydrates, and their roles in a healthy diet. This summary covers sources, functions, and the effects of deficiencies and excesses, along with cooking processes and chemical properties relevant to food technology. Ideal for AQA Food Science students.

Food & Nutrition

Hospitality & Catering Overview

Explore the essential components of the hospitality and catering industry, including job roles, service styles, and operational strategies. This summary covers key concepts such as employee rights, market competition, and financial management, providing a comprehensive understanding for students in hospitality studies.

Food & Nutrition

Hospitality & Catering A02 Insights

Explore essential concepts and operational strategies in the Hospitality and Catering industry with this comprehensive revision resource for WJEC Level 1/2. Covering customer service, kitchen operations, and compliance with health and safety regulations, this guide is designed to enhance your understanding and prepare you for exams. Ideal for students seeking to excel in their studies.

Food & Nutrition

Essential Nutrients Overview

Explore the vital roles of macro and micro nutrients in maintaining health. This summary covers carbohydrates, proteins, fats, vitamins, and minerals, detailing their functions, food sources, and the importance of a balanced diet for optimal well-being.

Food & Nutrition

Hospitality & Catering Essentials

Explore key concepts in hospitality and catering, including commercial vs. non-commercial services, food safety, employee roles, and media impact. This summary covers essential topics for food technology students, focusing on business fundamentals, culinary technology, and health regulations. Ideal for exam preparation and understanding the hospitality industry.

Food & Nutrition

Essential Food Safety Temperatures

Discover critical food safety temperatures to prevent bacterial growth and ensure safe food handling. This summary covers the danger zone (15-63°C), optimal cooking temperatures for various meats, and safe refrigeration practices. Ideal for food technology students and professionals.

Food & Nutrition

Food Safety & Allergies Overview

Explore essential concepts in food safety, allergens, and food-related illnesses with this comprehensive revision booklet for WJEC Level 1/2 Hospitality & Catering. Key topics include microbial growth, food intolerances, pathogens, and legal responsibilities in food handling. Perfect for exam preparation and understanding food hygiene standards.

Food & Nutrition

Essential Vitamins & Minerals

Explore the critical roles of essential vitamins and minerals in human nutrition. This comprehensive overview covers functions, sources, and deficiencies of key nutrients, including calcium, iron, magnesium, and vitamins A, C, D, and B-complex. Ideal for Food Technology students seeking to understand dietary requirements and their impact on health.

Food & Nutrition

Most popular content

An Inspector Calls: Character Insights

Explore in-depth analysis and key quotes for characters in J.B. Priestley's 'An Inspector Calls'. This resource covers Gerald Croft, Inspector Goole, Sheila Birling, Mrs. Birling, Eric Birling, and Eva Smith, focusing on themes of class, gender roles, and social responsibility. Ideal for students aiming for Grade 8 and above.

English Literature

Sociology of Education Overview

Explore comprehensive A-Level Sociology notes on the education system, covering key theories, policies, and sociological perspectives. This resource includes insights on marketisation, gender roles, cultural deprivation, and educational inequalities, providing a thorough understanding of how education shapes social stratification and individual achievement. Ideal for exam preparation and in-depth study.

Sociology

Comprehensive Crime & Deviance Overview

Explore an extensive revision of crime and deviance topics, including theories, types of crime, and the impact of media. This resource covers key concepts such as Marxism, functionalism, gender and crime, and the influence of globalization on criminal behavior. Ideal for students seeking a thorough understanding of criminology and its various theories. Type: Full Topic Revision.

Sociology

Sociology of Families: Comprehensive Revision

Dive into an extensive overview of family dynamics, perspectives, and patterns in sociology. This resource covers key concepts such as family diversity, gender roles, marriage, and the impact of social policies on family structures. Perfect for A-Level Sociology students preparing for Paper 2.

Sociology

WJEC Unit 4 Criminology

Criminology unit 4 detailed revision note

Criminology

aqa higher tier combined science - biology b1 : cell biology, paper 1

b1: cell biology - paper 1

Biology

Criminology: Crime & Punishment Overview

Comprehensive mindmaps covering key concepts in the Crime and Punishment topic for WJEC Criminology Unit 4. This resource includes detailed insights into the Criminal Justice System, crime prevention strategies, sentencing models, and the roles of various agencies. Ideal for A-Level revision, ensuring you grasp essential theories and legislative processes to excel in your exams.

Criminology

Macbeth: Guilt and Ambition

Explore the complex themes of guilt and ambition in Shakespeare's 'Macbeth'. This analysis covers key characters, including Macbeth and Lady Macbeth, their moral dilemmas, and the tragic consequences of their ambition. Ideal for students studying character motivations, thematic elements, and the psychological impact of power. Includes insights on the natural order, manipulation, and the descent into madness.

English Literature

AQA Biology: Key Concepts

Explore essential AQA Biology topics including Photosynthesis, Respiration, Homeostasis, Genetics, and Ecology. This comprehensive knowledge organizer covers key concepts such as energy transfer, hormonal control, and genetic variation, providing a solid foundation for your studies. Ideal for exam preparation and understanding biological processes.

Biology

Can't find what you're looking for? Explore other subjects.

Students love us — and so will you.

4.6/5

App Store

4.7/5

Google Play

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

Best app on earth! no words because it’s too good

Thomas R

iOS user

Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.

Basil

Android user

This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.

Rohan U

Android user

I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.

Xander S

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE Knowunity AI. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now

Paul T

iOS user

Stefan S

iOS user

Samantha Klich

Android user

Anna

iOS user

Best app on earth! no words because it’s too good

Thomas R

iOS user

Basil

Android user

David K

iOS user

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

Rohan U

Android user

Xander S

iOS user

Elisha

iOS user

Paul T

iOS user

Food & Nutrition

•

445

•

Updated Mar 20, 2026

•

1 page

Understanding Communicable Diseases

@uwu_fpjs

Communicable diseases are illnesses that can spread from person to person through different methods. These diseases are caused by various pathogens, including viruses, bacteria, fungi, and protists, and understanding how they spread is crucial for preventing infections.

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

Communicable Diseases and Their Causes

Health Alert: Gonorrhoea is a bacterial infection of the sexual organs. You can reduce your risk by avoiding contact with infected sex organs and using protection. If infected, antibiotics can treat the disease.