Chapter 16: Infectious Diseases Affecting the Skin- Part 1 Flashcards
Stratum corneum
25 cells thick, dead cells that have migrated from the deeper layers
Entire epidermis replaced every..
25-45 days
Keratin
Give cells the ability to withstand damage, abrasion and water penetration
Stratum basale
Several layers below the stratum corneum, attached to the dermis, source of cells that make up epidermis
Other protective characteristics of the skin and its defenses
Sebaceous (oil) glands
Antimicrobial peptides
Sweat
Lysozyme
How does sweat protect?
pH and flushing
How does sebum protect?
Microbes get stuck in it
Lysozyme
Specific to mucus membrane and eyes, attacks bacterial cell wall
What layer of the epidermis is the thickest?
Stratum corneum
Normal biota of the skin must be capable of…
Living in dry, salty conditions
Are a majority of the normal biota culturable?
No
Human microbiome project has shown that which genera are found on the skin?
Staphylococcus Propionbacterium Corynebacterium Malassezia Pseudomonas Janthinobacterium
Maculopapular rash diseases
Flat to slightly raised colored bumps
Maculopapular rash diseases types
Measles Rubella Fifth disease Roseola Scarlet fever
Fifth disease is caused by..
B19 parovirus
Roseola is caused by..
Human herpes virus
What does roseola do?
Changes color of skin
Scarlet fever is caused by..
Streptococcus pyogenes
Impetigo
Superficial bacterial infection, usually in children, near nose / mouth
Cellulitis
Bacterial infection that involves dermis and subcutaneous level
Rocky Mountain Spotted Fever
Caused by Rheketzia, spread by tick bite
Vessicular or pustular rash diseases
Chickenpox, smallpox, HSV
Conjunctivitis
Pink eye
Keratitis
Severe eye infection that can lead to destruction of cornea
Has there been a reduction in measles cases within the 20th century?
Yes because of vaccination programs
Symptoms of measles
- Begins with fever, runny nose, cough, red weepy eyes
- Fine rash appears within a few days
Where does the fine rash of measles begin?
Appears first on forehead, then spreads to rest of body
When do symptoms of measles generally disappear?
Within 1 week
Many cases of measles are complicated with…
Secondary infections
What are the most common secondary conditions of measles?
Pneumonia and earaches
Less common complications of measles
Encephalitis and subacute sclerosis panencehalitis (SSPE)
Measles is most contagious in what stage?
Red weepy eye stage
Febrile
Fever
Measles still kills about _____ people every year
700,000
Measles causative agent
Rubeola virus
Characteristics of rubeola virus
Pleomorphic, medium sized, enveloped
The envelope of the rubeola virus contains..
Two different types of spike proteins
What are the two spike proteins of the rubeola virus for?
One for viral attachment to host
One for fusion with host membrane
Rubeola virus genome
Single-stranded RNA
What family does the rubeola virus belong to?
Paramixoviridae
Host (s) of measles
Humans are only natural host
Measles virus (rubeola) is spread by..
Respiratory droplets
Before routine immunization, what percent of the population was infected?
Over 99%
Is measles still endemic in the US?
No
What illnesses are next to be eradicated?
Measles
Polio
Prevention of measles
Directed toward vaccination (usually given in conjunction with mumps, rubella, varicella vaccine, MMRV)
Is there an antiviral treatment for rubeola infection?
No
