b5 - communicable diseases Flashcards
define communicable diseases
- infectious diseases e.g tuberculosis, flu
- caused by pathogens, such as bacteria and viruses, that can be passed from one person to another
define non-communicable diseases
- e.g heart disease, arthritis
- cannot be transmitted from one person to another
how does diet affect health?
- too little or the wrong nutrients can lead to starvation, anaemia, or rickets for example
- too much food or the wrong type of food can lead to obesity, some cancers, type 2 diabetes
how does stress affect health?
too much stress linked to an increase risk of heart disease, certain cancers and mental health problems
how can life situations affect health?
- geographical location increased risk of certain diseases e.g malaria in tropical regions
- gender, fincancial status, ethnic group, number of children in a family
- free health care provided also reduces risk
- local sewage and rubbish disposals important for healthy population
give some examples of different types of diseases and health conditions interacting
1) virus’ living in cells, e.g human papilloma virus, can trigger changes leading to cancers
2) defects in immune system increase liklihood of communicable disease
3) immune reactions can trigger allergies
4) severe physical health issues can lead to mental health problems, e.g depression
5) malnutrition can lead to deficiency diseases, weakened immune system, obesity, cardiovascular disease, type 2 diabetes, or cancer
which pathogens cause the most diseases in plants?
viruses and fungi
which pathogens cause the most communicable diseases in humans?
bacteria and viruses
what happens when bacteria or viruses enter the body?
they reproduce rapidly
how does bacteria make a person feel ill?
by producing toxins (poisons), may also damage the body cells
how do viruses make you feel sick?
much smaller than bacteria, reproduce inside cells, damaging and destroying cells
how are pathogens spread through air?
- bacteria viruses and fungal spores can be spread through the air from one animal or plant to another
- humans spread pathogens when they cough or sneeze.
- the droplets of the water carrying the pathogens are inhaled by another person - droplet infection
how are pathogens spread through direct contact?
- sexually transmitted infections can be passed by sexual contact
- skin contact, or enter via cuts, scratches or needle punctures
- animals e.g mosquitos can act as vectors and carry pathogens from one individual to another
- if a portion of a diseased plant is left in a field it could infect the whole crop
how are pathogens spread through direct contact?
- drinking contaminated water can allow pathogens to enter the digestive system
- fungal spores in splashes of water can spread plant diseases
what did Ignaz Semmelweiss discover?
- realised that infection could be transferred from person to person in a hospital
- he told his staff to wash their hands between treating patients. This reduced number of deaths.