Viral Diseases

Question 1

Measles

Answer 1

The main symptoms are a fever and a red skin rash.

The virus is spread by the inhalation of droplets and is spread by coughs and sneezes.

It can cause blindness, brain damage and can be fatal.

There is no treatment for measles, so if someone gets it, they should be isolated to stop the virus from spreading.

It is quite a rare disease now because the living conditions have improved

Question 2

HIV/aids

Answer 2

Around 35 million people globally are infected by HIV, which can eventually lead to aids.

Many people do not realise they have it because the virus only causes a mild, flu-like illness to begin with

It damages the immune system very badly so it cant defend against things like cancer

HIV is spread by sexual contact or exchange of body fluids such as blood which occurs when drug users share needles.

Question 3

Tobacco mosaic virus

Answer 3

It is spread on many different species of plants including tomatoes.

It causes a distinct mosaic pattern of discolouration on the leaf as the virus destroys the cell.

It is spread by diseased plant material coming into contact with healthy plants.

There is no treatment for this, but you can grow TMV resistant crops and keep good field hygiene and pest control to prevent the spread of it.