Made up of one cell They have the power to divide, can multiply on their own Exists everywhere but majority are completely harmless Viruses: Too small to be seen by the naked eye They can’t multiply on their own Viruses consist of genetic materials (DNA or RNA) surrounded by a protective coat of protein making them capable of latching onto cells and getting inside them Parasites: Organisms that live inside humans or other organisms that act as hosts Are harmful to humans Dependant on their hosts for food and energy Fungi:
Can change from one form (unicellular yeasts or branching filamentous moulds) to another depending on their environment Moulds can be seen with the naked eye whereas yeasts cannot More than 50,000 species of fungi but less than 200 are associated with human disease 1. 2 Bacteria: Salmonellosis, tuberculosis, MRSA, food poisoning, dysentery, bronchitis, ear infections, strep throat/tonsillitis, pneumonia, gonorrhea, syphilis and chlamydia Viruses: Influenza, common cold, stomach flu, pneumonia, ear infections, HIV/AIDS, herpes, warts, and encephalitis Fungi: Valley fever, athlete’s foot, ringworm and yeast infection
Parasites: Worms, malaria and sleeping sickness 1. 3 Infection is an invasion by and multiplication of microorganisms in a bodily part or tissue, which may produce subsequent tissue injury. Colonisation is when a bacterial strain invades a region of your body and starts to rapidly divide (setting up a new colony) 1. 4 A localised infection affects one area of the body only. The area becomes painful, red and inflamed, with the signs and symptoms remaining local to the injury. On the other hand a systemic infection is an infection that enters the blood stream and makes the patient feel very ill.
The patient might complain of tiredness, vomiting, headache, nausea, flushing, high temperature or aching limbs. 1. 5 Poor practice that may lead to the spread of infection could be any of the following not washing your hands/poor infection control, not wearing personal protective equipment (PPE), not storing or cooking foods properly, not cleaning your surroundings, not covering your nose or mouth when sneezing or coughing. 2. 1 The conditions needed for the growth of micro-organisms are warmth, moisture and nutrients. In this environment bacteria is then able to rapidly multiply, each bacterium splits into two every 20 minutes.
2. 2 An infective agent may gain entry to the body through any of the body’s orifices for example mouth, vagina, rectum, nose and urethra. When a person is in hospital with their immune system already lower than usual this makes a patient more susceptible to infection entering the body. For example they may have a break to their skin (wound), or a catheter in situ which are just two ways in which an infective agent may enter the body. 2. 3 Common sources of infection are split into two categories exogenous and endogenous. Endogenous when the infectious agent comes from the patient’s own body.
Endogenous sources of infections become important when the person’s immunity is low such as in cases of contamination during surgery, malnutrition, impairment of blood supply and debilitating diseases such as AIDS, diabetes or any other accompanying infection. The exogenous sources of infection are brought inside the body from the person to person contact. Exogenous sources of infections can be human, animal, or environmental in origin. 2. 4 Infective agents can be transmitted to a person through five methods. Direct contact would be if you were to touch hands with another person or patient.
Indirect contact may be if you come into contact with a contaminated object. Airborne transmission means that you may inhale the pathogen that is being carried on dust particles or skin scales. A droplet contact with contaminated secretions released through sneezing or coughing and finally arthropods which are basically flies, mites and bugs etc. They transmit the pathogen by sucking, biting or via their faeces. 2. 5 Factors that make it more likely that an infection will occur include proximity to others (either infected or uninfected people), dirty and/or contaminated areas, equipment or laundry, and contact with body fluids.