Diseases we need to know

Viral

Measels

Spread by air - sneezing or coughing

Develop red skin rash and fever (high temperature)

Can be fatal if there are complications eg. can lead to pneumonia (lung infection) or encephalitis (brain infection)

Cure: vaccination when young

HIV

Spread by sexual contact or exchanging bodily fluids like blood eg. by sharing needles

Causes flu-like symptoms for a few weeks then nothing for a few years - can be controlled with antiretroviral drugs which stop the virus from replicating

Virus attacks immune cells - at stage where system is so damaged it cannot cope with cancer or other infections is known as AIDS - late stage of HIV

Tobacco Mosaic Virus

Virus affecting plants eg. tomatoes

Causes mosaic pattern on the leaves - parts become discoloured

Plants can't carry out photosynthesis so well so have stunted growth

Fungal

Rose Black Spot

Causes purple or black sports to develop on leaves of rose plants - causes leaves to turn yellow and drop off

Less photosynthesis so stunted growth

Spreads through environment by water or wind

Gardeners treat it using fungicides and by stripping the plant of its affected leaves, which are then destroyed. and the tools used are sterilised

Protist

Malaria

Vector of the disease is mosquitos

Mosquito first bites an infected human and becomes infected

Later after the parasite has completed its 8 day cycle when the mosquito has its blood mean it transmits the disease to an uninfected human through their blood vessel

Causes episodes of fever and can be fatal

Reduce spread by stopping mosquito's from breeding

Protection using insecticides and mosquito nets

Bacterial

Salmonella

Causes food poisoning

Infected people suffer from fever, stomach cramps, vomiting and diarrhoea

Get it by eating contaminated food - eg. it was prepared in unhygienic conditions

Controlled where poultry are given a vaccination

Gonorrhoea

Sexually transmitted infection

Passed on by sexual contact eg. unprotected sex

Symptoms are pain when urinating, thick yellow or green discharge from vagina or penis

Originally treated with penicillin, but bacteria are now resistant

People should use contraception such as condoms and take antibiotics

How to reduce/prevent spread of disease

Being hygienic - wash hands and after sneezing or being with an infected person

Destroying vectors - prevents disease being spread - use insecticides or destroy their habitat so they can no longer breed

Isolating infected individuals - prevents the disease from being passed on

Vaccination - means people and animals cannot develop the infection and pass it on to someone