Study Notes on Viruses and Bacteria

• Study notes on viruses, parasites, growth and movement of bacteria, infection and immunity.

Growth of Bacteria

• There are two stages: active and inactive.
• Active: grows rapidly, needs a dark, damp, dirty area with food, and absorbs food to grow and divide.
• Inactive: conditions unfavorable cause death or inactivity.
  • Spores can die by sterilization or sporicidal methods.
  • When conditions improve, bacteria become active again.

Movement of Bacteria

• Cocci travel through air or dust.
• Bacilli and spirilla use flagella and cilia to move through liquids.

Viruses

• Viruses are smaller than bacteria.
• Viruses cause diseases such as the common cold, measles, and hepatitis.
• Viruses require a living host.
• Some viruses can be treated or prevented with vaccinations.
• Hepatitis B virus: a bloodborne pathogen that infects the liver and can be prevented by a vaccine.
• Human immunodeficiency virus (HIV): attacks the immune system, leads to acquired immunodeficiency, and spreads through the bloodstream.
• Human papillomavirus (HPV): is invasive and hard to kill and can cause genital warts, plantar warts, cervical changes, and cervical cancer.

External Parasites

• External parasites live on or get nutrients from a living host.
• Proper disinfection procedures are necessary to prevent the spread of contagious fungi, bacteria, and mites.
• Parasitic fungi: including molds and yeast, cause non-contagious conditions like dandruff and seborrheic dermatitis.
• Parasitic mites: insects that cause contagious diseases like mites and lice.
• Lice: spread person to person through infected items like combs and brushes, often accompanied by head scratching, redness, or bite marks, and can be treated with pediculicide shampoo.

Bacteria Types

• Bacteria: a germ that can be non-pathogenic or pathogenic.
• Nonpathogenic bacteria: harmless and beneficial; 70% of bacteria are nonpathogenic, living on the skin and inside the body protecting us from harmful bacteria.
  • They don't cause disease, may have medical applications or health-enhancing properties, and facilitate the decay of refuse/vegetation while improving soil fertility.
• Pathogenic bacteria: can live everywhere and cause infection and disease.
  • They produce toxins (poisons) and spread easily through contaminated tools/implements, dirty hands, and fingernails.
• Cocci: round-shaped cells that appear in single or groups.
  • Staphylococci: found in groups and form pus often found in boils.
  • Streptococci: found in rows and form pus found in strep infections.
  • Diplococci: found in pairs that cause pneumonia.
  • Bacilli: rod-shaped and the most common can cause tuberculosis and tetanus.
  • Spirilla: squiggly with a tail, highly contagious, and cause Lyme disease, syphilis, and cholera.

Infection

• Infection: when pathogenic bacteria or viruses enter the body, multiply, and disrupt normal bodily functions.

Transmission

• Direct Transmission: pathogens transfer through touch or exchange of bodily fluids.
• Indirect Transmission: pathogens transfer through the air or contact with a contaminated object.
• Contagious Infection (Communicable Disease): when an infection is transmitted from one person to another.
• Micro-Organisms: spread frequently to a new person but do not cause infection unless in the body.
• Bloodborne Pathogens: carried through blood or bodily fluids and can spread when the skin is broken.
• Local Infection: is confined to a small area, like a pus-filled boil or a pimple.
• General Infection (Systemic): carried by the circulatory system, affecting all parts of the body.
• Asymptomatic Carrier: carries disease-producing bacteria without showing symptoms.
• Universal Precautions: using infection control procedures with all clients.

Spreading Infection in the Salon

• Common spreading methods include:
  • Sharing mugs/cups
  • Coughing/sneezing
  • Open sores
  • Unclean hands/implements
  • Unsanitary conditions
  • Using the same implements.

Immunity

• Immunity: active and passive.
• Active immunity: takes time to develop, produces antibodies after exposure, caused by disease exposure or vaccination, and is usually long-lasting.
• Passive immunity: provides immediate protection, lasts only a few weeks/months, and antibodies are given rather than produced.