GCSE · Biology · AQA · Spec 8461

Measles

Nobody touches anybody. One person sneezes, someone nearby breathes in, and the measles virus has moved into a new body. Here's how that happens, and why it matters.

Follow one sneeze

Stage 1 of 5: A sneeze or a cough. paused

A sneeze or a cough · 1/5Drag to follow the virus

Someone with measles sneezes or coughs. Tiny droplets spray out, and the measles virus is travelling inside them.

How measles gets from one person into the next

What kind of disease is it?

Pin measles down

You've just followed the measles virus from one person to the next. Now place it among all the things that cause disease. Two questions matter: what kind of pathogen is it, and which route does it travel by?

Which of these is closest to what you think right now?

Measles is caused by bacteria. Bacteria are the germs that cause infectious diseases.You catch measles by touching someone who has it, like touching their rash.It's a virus, and you catch it by breathing in droplets from sneezes and coughs.Measles spreads by water. Droplets are water, after all.

How sure are you?

I'm sureI think soI'm guessing

Measles is caused by bacteria. Bacteria are the germs that cause infectious diseases.

This is a common misconception

Bacteria are one type of pathogen, but not the only one. Pathogens are microorganisms that cause infectious disease, and there are four types: viruses, bacteria, protists and fungi. Measles is a viral disease. It's caused by a virus, not bacteria.

You catch measles by touching someone who has it, like touching their rash.

This is a common misconception

Pathogens can spread in three ways: by direct contact, by water or by air. Touching is the direct-contact route, but it isn't the route to give for measles. The measles virus is spread when droplets from sneezes and coughs are breathed in. That's the air route.

It's a virus, and you catch it by breathing in droplets from sneezes and coughs.

This matches the evidence

Spot on. Measles is a viral disease, and the virus is spread by inhalation of droplets from sneezes and coughs. Of the three routes a pathogen can use (direct contact, water, air), that's the air route.

Measles spreads by water. Droplets are water, after all.

This is a common misconception

Nice thinking about the droplets, but 'spread by water' is a different route. The measles droplets come out in sneezes and coughs and travel through the air until someone breathes them in. So measles uses the air route, not the water route.

Pathogens are microorganisms that cause infectious disease. They can be viruses, bacteria, protists or fungi. They may infect plants or animals, and they spread by direct contact, by water or by air. Measles: a virus, travelling by air.

Predict, then check

The virus has just been breathed in. Commit to an answer before you look.

Once the measles virus is inside someone's body, where does it live and reproduce?

Just a rash?

Reason it through

Why are most young children vaccinated against measles?

Link 1 of 3

First link · your turn

Fever and a red rash sound like a few days off school. Is that all measles is?

Locked — reveal the link above first

Your turn to write it

Tell the whole measles story

Explain how measles is spread from one person to another, and why most young children are vaccinated against it. [5 marks]

Your answer

0 words · your answer stays on this page and is not sent anywhere.

The mark scheme

Measles is caused by a virus. (1 mark)
The virus is carried in droplets from sneezes and coughs. (1 mark)
Another person breathes in (inhales) the droplets. (1 mark)
Measles is a serious illness. (1 mark)
It can be fatal if complications arise. (1 mark)

Model answer

Measles is caused by a virus. When someone with measles sneezes or coughs, droplets carrying the virus spray out into the air. Another person breathes in (inhales) those droplets, and the virus gets into their body. Most young children are vaccinated because measles is a serious illness that can be fatal if complications arise.

A full answer names the pathogen, says what carries it (droplets from sneezes and coughs), says how it gets in (it's inhaled) and gives the reason for vaccination (serious, and can be fatal if complications arise).

WHAT YOU'VE LEARNED

A quick recap of today's lesson.

One sneeze, one breath in, and a virus has a new home.

What you need to know

Pathogens are microorganisms that cause infectious disease. They may be viruses, bacteria, protists or fungi.
Pathogens may infect plants or animals. They can be spread by direct contact, by water or by air.
Bacteria and viruses may reproduce rapidly inside the body.
Viruses live and reproduce inside cells, causing cell damage.
Measles is a viral disease. Its symptoms are a fever and a red skin rash.
The measles virus is spread by inhalation of droplets from sneezes and coughs.
Measles is a serious illness that can be fatal if complications arise. For this reason most young children are vaccinated against measles.

The big picture

Measles is a disease caused by a virus. It spreads through the air: droplets from an infected person's sneezes and coughs are breathed in by someone else. Inside the body, viruses live and reproduce inside cells, damaging them. The symptoms of measles are a fever and a red skin rash. Measles is a serious illness that can be fatal if complications arise, which is why most young children are vaccinated against it.

Key points

1Measles is a virus on a journey: out in a sneeze or cough, through the air, in with the next person's breath.

2No touching is needed. Breathing in the droplets is enough, so measles is an air-route disease.

3The damage happens inside cells, because that's where viruses live and reproduce.

4Fever and a red rash are the symptoms, not the whole story: measles can be fatal if complications arise.

5To explain how measles spreads, say what carries it (droplets from sneezes and coughs) and how it gets in (inhaled).

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Worked example

Problem

Jo is asked to explain how measles is spread from one person to another. Jo writes: 'Measles spreads through the air.' How can Jo turn that into a full answer?

⚠ Watch out

Calling measles 'just a rash'. The fever and red skin rash are only the symptoms. Measles is a serious illness that can be fatal if complications arise.

🧠

Memory hook

Measles is a hitch-hiker. It rides out on a sneeze or a cough, hops in with the next person's breath, and sets up home inside their cells. Out, in, inside: then a fever and a red rash.

✓

Check yourself

Cover the page. Tell the journey of measles in four steps, from one person's sneeze to the next person's symptoms. Then give, in one sentence, the reason most young children are vaccinated against it.

Flashcards

(12)

What is a pathogen?

A microorganism that causes infectious disease.

The four types of pathogen

Viruses, bacteria, protists and fungi.

What can pathogens infect?

Plants or animals.

The three ways pathogens can be spread

By direct contact, by water or by air.

What type of pathogen causes measles?

A virus. Measles is a viral disease.

How is the measles virus spread?

By inhalation of droplets from sneezes and coughs.

What does 'inhalation' mean?

Breathing in.

Where do viruses live and reproduce?

Inside cells.

What happens to the cells a virus reproduces in?

They are damaged: viruses cause cell damage.

Which two types of pathogen may reproduce rapidly inside the body?

Bacteria and viruses.

The two symptoms of measles

A fever and a red skin rash.

Why are most young children vaccinated against measles?

Measles is a serious illness that can be fatal if complications arise.

Tap any card to flip it, or use Study as deck to go through them one at a time. In the full lesson these run as a spaced-repetition deck — you rate each card Hard, Good or Easy and the tricky ones keep coming back until they stick.

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Follow one sneeze

Pin measles down

Tell the whole measles story

More AQA GCSE Biology topics