Chapter 21,part B Microbial Diseases of the Skin and Eyes
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings B.E Pruitt & Jane J. Stein Chapter 21, part B Microbial Diseases of the Skin and Eyes
Poxviruses ·Smallpox(Variola ·Smallpox virus (Orthopox virus) 。Variola major has 20%mortality 。Variola minor has <1%mortality ·Monkeypox 。Prevention by smallpox vaccination Figure 21.9
• Smallpox (Variola) • Smallpox virus (Orthopox virus) • Variola major has 20% mortality • Variola minor has <1% mortality • Monkeypox • Prevention by smallpox vaccination Poxviruses Figure 21.9
Herpesviruses (a)Initial infection:chickenpox(varicella) Nerve cell in dorsal Latent root ganglion viral DNA Spinal cord Varicella-zoster virus (Human herpes virus 3) Viruses move up peripheral nerve 。Transmitted by the respiratory route Causes pus-filled vesicles Virus may remain latent in dorsal root ganglia Figure 21.10a
• Varicella-zoster virus (Human herpes virus 3) • Transmitted by the respiratory route • Causes pus-filled vesicles • Virus may remain latent in dorsal root ganglia Herpesviruses Figure 21.10a
Shingles (b)Recurrence of infection:shingles(herpes zoster Activation of viral DNA in nerve cell Viruses Spinal cord Viruses move down Reactivation of latent peripheral nerve HHV-3 releases viruses that move along peripheral nerves to skin. Figure 21.10b
• Reactivation of latent HHV-3 releases viruses that move along peripheral nerves to skin. Shingles Figure 21.10b
Herpes simplex 1 and Herpes simplex 2 Human herpes virus 1 and HHV-2 。 Cold sores or fever blisters (vesicles on lips) Herpes gladiatorum (vesicles on skin) Herpes whitlow(vesicles on fingers) Herpes encephalitis (HHV-2 has up to a 70%fatality rate) HHV-1 can remain latent in trigeminal nerve ganglia HHV-2 can remain latent in sacral nerve ganglia Acyclovir may lessen symptoms
• Human herpes virus 1 and HHV-2 • Cold sores or fever blisters (vesicles on lips) • Herpes gladiatorum (vesicles on skin) • Herpes whitlow (vesicles on fingers) • Herpes encephalitis (HHV-2 has up to a 70% fatality rate) • HHV-1 can remain latent in trigeminal nerve ganglia • HHV-2 can remain latent in sacral nerve ganglia • Acyclovir may lessen symptoms Herpes simplex 1 and Herpes simplex 2
Measles (Rubeola) 。Measles virus Transmitted by respiratory route Macular rash and Koplik's spots Prevented by vaccination Encephalitis in 1 in 1000 cases 。Subacute sclerosing panencephalitis in 1 in 1,000,000 cases Figure 21.14
• Measles virus • Transmitted by respiratory route • Macular rash and Koplik's spots • Prevented by vaccination • Encephalitis in 1 in 1000 cases • Subacute sclerosing panencephalitis in 1 in 1,000,000 cases Measles (Rubeola) Figure 21.14
Measles (Rubeola) 500000 Vaccine licensed Measles 450000 1000 400000 90 350000 300000 250000 200000 200 100 150000 0 1994 1996 1998 2000 2002 Year 100000 50000 0 960 1965 1970 1975 1980 1985 1990 1995 2000 Year Figure 21.13
Measles (Rubeola) Figure 21.13
Rubella (German Measles 。Rubella virus 。Macular rash and fever 。Congenital rubella syndrome causes severe fetal damage 。Prevented by vaccination Figure 21.15
• Rubella virus • Macular rash and fever • Congenital rubella syndrome causes severe fetal damage • Prevented by vaccination Rubella (German Measles) Figure 21.15
A 1905 list of skin rashes included #1-measles,#2- scarlet fever,#3-rubella,#4-Filatow-Dukes (mild scarlet fever）,and#5- 。Fifth Disease Human parvovirus B19 produces milk flu-like symptoms and facial rash 。Roseola Human herpesvirus 6 causes a high fever and rash, lasting for 1-2 days
• A 1905 list of skin rashes included #1-measles, #2- scarlet fever, #3-rubella, #4-Filatow-Dukes (mild scarlet fever), and #5- • Fifth Disease • Human parvovirus B19 produces milk flu-like symptoms and facial rash • Roseola • Human herpesvirus 6 causes a high fever and rash, lasting for 1-2 days
Cutaneous Mycoses Dermatomycoses:tineas or ringworm 。Metabolize keratin 。Trichophyton infects hair,skin,nails ·Epidermophyton infects skin and nails 。Microsporum infects hair and skin 。Treatment 。Oral griseofulvin 。Topical miconazole
• Dermatomycoses: tineas or ringworm • Metabolize keratin • Trichophyton infects hair, skin, nails • Epidermophyton infects skin and nails • Microsporum infects hair and skin • Treatment • Oral griseofulvin • Topical miconazole Cutaneous Mycoses