1. Why is it difficult to treat viral nfxn
    • Viruses use host cell enzymes and substrates to reproduce
    • Drugs that affect these viruses will also affect the host
    • Successful drugs affect the biochemical processes unique to viral replication.
  2. Herpes Simplex Viruses (Type 1)
    • Type 1 (HSV 1)
    • Cause classic cold sore
    • Recurrent
    • Severity increases with age and immunosupression
  3. Herpes Simplex 2
    • Genital Herpes
    • Recurrent
  4. Herpes Simplex Commonalities
    • There is not really a clear divide between the two types, however. HSV1 can also cause genetal sores, and vise versa.
    • Both viruses lay dormant within a nerve route until outbreak.
    • Most infective at time period immediately before outbreak (lesion).
  5. HSV Recurrence
    • After primary infection the virus remains in the body in a dormant state in the nerve ganglia
    • patient is asymptomatic
  6. HSV Triggers
    • Reactivation of infection triggers the virus to travel the pathway of the nerve to the skin surface
    • Triggers may be:
    • Physical or psychological stress
    • Sun
    • Trauma
    • Fever
    • Menses
    • Fatigue
  7. HSV Spreading
    • How spread
    • Direct contact
    • Autoinnoculation (Spread of either type from one body part to another)

    • Outbreaks
    • Last 3-10 days
    • Active shedding
    • First 3-5 days

    • Spread by:
    • Respiratory droplets
    • Direct contact with active lesion
    • Virus containing fluid
  8. Herpevac
    • 1 in 4 women will acquire HSV
    • Current testing decreased risk of acquiring by 75%
    • Did not effect HSV1 if already infected
    • Not effective for men
    • Did not ultimately come to market.
  9. Herpes Zoster
    • AKA Shingles
    • Caused by reactivation of latent Varicella-zoster virus
    • Those previously exposed to chicken pox
    • Contagious to those never exposed to chickenpox
    • Dormant virus resides in the dorsal root ganglia of the sensory cranial and spinal nerves
    • Multiple lesions occur on the skin innervated by the infected nerve
    • Disease of immunosuppression
  10. Zostavax
    • Vaccine for chicken pox/shingles
    • For those over 60
    • Prevents shingles in over half of those over 60---reduces pain in others.

    • Contraindications
    • Allergic reactions to gelatin
    • Allergic reactions to neomycin (aminoglycocides)
    • Weakened immune system
    • HIV/AIDS
    • Steroids
    • Cancer treatment
    • Hx of leukemia, lymphoma
    • Pregnancy
    • Temp over 101
  11. Purine Nucleoside Analogs
    Acyclovir (Zovirax)
    • DNA polymerase inhibitors
    • Suppresses synthesis of viral DNA
    • First choice for infections caused by herpes simplex and varicella-zoster virus
    • Administered topically, orally and IV
  12. Acyclovir (Zovirax) Adverse Effects
    • Intravenous therapy
    • Phlebitis
    • Nephrotoxicity

    • Oral therapy
    • Gastrointestinal
    • Vertigo

    • Topical
    • Stinging sensations
  13. Acyclovir (Zovirax) Pt education
    • Acyclovir IS NOT A CURE
    • It will not prevent spread to others
    • Use of condoms (Genital Herpes)
    • No sexual contact when active lesions are present
    • Use of OTC lotions, creams may delay healing and cause spread of lesions, may lead to selfinnoculation!
  14. Cytomegalovirus (CMV)
    • CMV is related to the herpes virus and is present in almost everyone.
    • Especially seen in those who are immunosuppressed
    • AIDS (brought CMV to the forefront), Chemo, Transplants
    • Infections of the eye are very common.
  15. Cytomegalovirus
    CMV Retinitis
    • Floaters
    • Spots, bugs and spider-webs
    • Light Flashes
    • Blind Spots
    • Blurred Vision
    • Obstructed areas of vision
    • Sudden decrease in vision
  16. Image Upload 1
    Basically destroys vision
  17. Valganciclovir
    • Prodrug version of ganciclovir (acyclover). Becomes identical to acyclover after metabolism.
    • Can be given orally
    • Adverse effects: Blood dyscrasias (decreases of WBCs, RBCs, and platelets)
    • Should be taken with food
    • Has potential for mutagenesis and carcinogenesis….handle carefully
    • Take intact…no crushing or chewing, increases mutagenic and carcinogenec properties. Prep should be done under a hood, with gloves, wash hands.
    • HCW use cytotoxic chemo precautions
  18. Hepatitis
    • 6 types of Viral Hepatitis: A; B; C; D; E; G
    • Vary by:
    • Mode of transmission
    • Manner of onset
    • Incubation periods
    • Enteral Forms: A and E (Vaccine for A)
    • Parenteral (needle sticks) Forms: B,C E G (Vaccine for B)
    • E occurs in both, so its more virulent.
    • C is more contagious than HIV, so use precautions when treating pt with HepC.
  19. Accute vs. Chronic Hepatitis
    • Acute:
    • Lasts ~ 6 months
    • Liver inflammation, jaundice, Elevation of Liver enzymes
    • Usually resolves spontaneously.
    • All forms can be accute.

    • Chronic:
    • Only B, C ,D and G can cause chronic hepatitis (not A and E).
    • 90% caused by B and C
    • 1.5% of Americans have chronic infection with HBV or HCV
    • 5 times more than the number infected with HIV
  20. Interferon Alpha
    • Interferon Family (used to treat) can be Alpha, Beta, Gamma
    • Actions
    • Antiviral
    • Immunomodulatory
    • Antineoplastic
    • Administration
    • Parenterally, IM or SQ
    • Therapeutic effects
    • HBV
    • Improved liver histology in 40%
    • HCV
    • After 12 months-40-50% have normalized liver function

    • Adverse effects
    • Flu-like syndrome
    • Depression
  21. Ribavirin
    • Available in 2 formulations
    • Inhaled (For Respiratory Syncytal Virus –RSV )
    • Oral ( For Chronic Hepatitis )

    Action is really unknown although several actions are thought to be actively anti-viral

    Contraindicated for use in pregnancy nor should pregnant nurses administer the drug (Aerosol)

    Current treatment for chronic hepatitis C

    • Action
    • Ribavirin-nucleoside analog; Mechanism unknown

    Kit—contains two drugs, Ribavirin - PO, Interferon Alfa - SQ

    Adverse effects

    • Flu-like symptoms
    • Depression
    • Hemolytic anemia
    • Birth defects
  23. Peginterferon Alfa-2b
    • Treatment of HCV
    • Approved for stand-alone therapy… initial research seems to identify improved effectiveness with ribavirin
    • Long-acting form of interferon alpha 2b
    • Half life of 40 hours vs 2-3 hrs
    • Can be given 1x week vs 3 times a week
    • Identical side and toxic effects
  24. Drugs for Flu
    • Influenza Vaccine
    • Annual. Changes every year in accordance with what is predicted to come to the US from Asia the year before. Not always accurate.
    • Inactivated virus. Cannot get flu from vaccine, but may have rxn due to egg content in vaccine serum.
    • 70-90% effective
    • Protection lasts 6 months
    • Elderly population works only 30-40%, and will last only ~ 4 months
    • Given IM
    • Always ask "Are you allergic to eggs? Have you ever had a rxn to flu vaccine?"
    • Use to give a live virus called Guillin Berette. Could cause paralysis. Will have some pts who will not take flu vaccine now because they're still afraid of it.
  25. Flu Mist
    • Live, attenuated (virulent components removed) Influenza Vaccine (LAIV)
    • Temperature sensitive (Cold Adapted). Must be kept cold, almost frozen.
    • Trivalent; composed of and specific to three viruses.
    • Intranasal, rub nares together, do not blow nose afterwards.
    • Approved last year
    • Not for everyone
  26. You should NOT use Flu Mist if you:
    • are under 5 years of age
    • are aged 50 years or over
    • have asthma or other reactive airway diseases
    • have chronic underlying medical conditions that may predispose you to severe flu infections
    • have problems with immune suppression, including those with immune deficiency diseases, such as AIDS or cancer, and people who are being treated with drugs that cause immunosuppression
    • are allergic to eggs or to a previous dose of the vaccine
    • children or adolescent receiving aspirin or other salicylates ----->(Reyes Syndrome).
    • History of Guillain-Barre’ syndrome
    • Pregnant woman
  27. Flu Mist Special Considerations
    • Children age 5-8 who have not received injection need 2 doses at least 6 wks apart
    • Must be stored at 15 degrees C
    • Thaw in hand and administer immediately OR
    • Thaw in refrigorator
    • Should only be thawed for 24 hours
    • Administer 1/2 of single use sprayer in one nostril and remainder in other
    • In upright position
    • Don’t repeat if sneezes
    • Mild illness is OK, if fever >101 degrees, do not give.
    • Cost ~$46 per dose
    • Other immunizations??
    • Inactivated viruses OK
    • Live viruses 4 weeks apart from flu inhaler.
  28. Amantadine and Ramantadine (1st gen flu meds)
    • First Generation Drugs
    • Used for prophylaxis and treatment of Influenza A
    • Should not take the place of vaccination
    • Adverse effects:
    • Nervousness
    • Lightheadedness
    • difficulty in concentration
    • Sleep disturbances
    • DO NOT use in pregnant and lactating women
  29. Oseltamivir and Zanamivir (2nd gen flu meds)
    • 2nd Generation
    • Neuraminidase Inhibitors
    • Suppress both Influenza A and B
    • Not approved for prophylaxis ~ seems to have some efficacy
    • Only for use in those >18
    • Symptoms for no more than 2 days
    • Oseltamivir ~ oral
    • Zanamivir ~ Inhaled powder
  30. Human Papaloma Virus (HPV) Vaccine
    • Gardasil Vaccine:Targets 4 viruses that cause up to 70% of all cervical cancers and 90% of genital warts
    • Cervarix: Targets 2 viruses known to cause cervical cancer.
    • CDC recommends vaccination for all girls 11 -12 years, and all boys age 9-26 (gardacil)
    • 13-26 years of age if not already vaccinated (only ages tested)
    • Series of 3 injections over 6 months
    • No serious side effects (yeah right) but will see fainting, seizures
  31. SARS: Severe Acute Respiratory Syndrome
    • Coronvirus ~SARS-CoV
    • Closely related to common cold
    • Results in atypical pneumonia
    • Time from exposure to onset of symptoms, 2 - 11 days
    • Fever ~ 100.4 or higher
    • Myalgia
    • HA
    • Malaise
    • Chills
    • Dry, nonproductive cough
    • Difficulty breathing
  32. West Nile Virus
    • Detection of IgM antibody to WNV in serum or CSF
    • Collected within 8 days of disease onset
    • Recent vaccination or infection with other associated viruses may cause a false positive
    • Plague Reduction Neutralization Test (PRNT)
  33. West Nile Virus (WNV)
    • First documented in 1937
    • Arbovirus
    • Similar to yellow fever, dengue and St. Louis encephalitis
    • Risk factors:
    • Advanced age
    • Immunosuppression

    • Mild infection
    • Sudden fever with
    • malaise
    • anorexia
    • HA
    • N/V
    • Symptoms last 3-6 days
    • Severe infection
    • 1 in 150 Cases
    • aseptic meningitis
    • Encephalitis
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