B3 - Infection And Response

An illness or disorder of the body or mind that leads to poor health

Communicable diseases

Transmissible- can be passed from one person to another

Bacteria Viruses Fungi Protoctists

Direct contact Contaminated water Coughing or Sneezing Droplets carried in the air

Good hygiene Effective sanitation Waste disposal

• keep food cold to slow bacteria and fungi reproduction • wash hands and clean surfaces to avoid contamination • cook food throughly to kill pathogens • use separate utensils for uncooked meat and cover food to prevent contamination

Direct contact : Washing with soap, especially after using the bathroom, to remove pathogens Airborne: Use tissues to catch sneezes and coughs and dispose of used tissues

• Dispose of waste food to prevent prevalence of flies which act as a vector • cover rubbish bins and remove to landfill for disposal or burning regularly

Water borne: Homes and public places should have plumbing and drains to remove faeces and waste safely; these drains can carry pathogens - raw sewage should be treated to remove solid waste and kill pathogens before being released into the environment

Vaccination Destroying vectors

NOT living - no nucleus organelles or cytoplasm

through hijacking when Inserting their genetic material into host cells and creating new protein capsules to build new viral particles - once many copies have been made, the host cells may burst open releasing the viral particles which can go an infect other cells

Seen in children

Fever Red skin rash

Virus is spread by inhalation of droplets from coughs and sneezes - makes it very infectious

No treatment so if someone becomes infected they should be isolated Vaccinations program has reduced cases of measles

Human immunodeficiency Virus

• Flu like illness • If untreated it can travel to the lymph nodes and attack cells of the immune system • can stay hidden for years until the immune system is badly damaged it can no longer deal with other infections or cancer

• Direct sexual contact • exchange of bodily fluids such as blood e.g sharing needles • from mother to child during birth or in breast milk

No cure for HIV although antiviral drugs can be used in early stages of the infection to slow the progress to aids or even stop it

Pathogen that infects plants damages chloroplasts

first virus of any kind to be isolated by scientists

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