COVID-19 Treatment with Remdesivir and Paxlovid

FDA Approved Medications

• Remdesivir approved for treating COVID-19 in hospitalized patients 12 years and older
• Paxlovid (nirmatrelvir and ritonavir) approved for treating mild-to-moderate COVID-19 in adults and pediatric patients 12 years and older

Human Diseases Associated with B19 Parvovirus

• Erythema Infectiosum (Fifth Disease)
• Joints in hands and knees are most frequently affected
• Symptoms include fever, malaise, myalgia, chills, and itching
• Incubation period: 1-3 weeks
• Specific IgG antibodies appear 15 days postinfection
• Treatment is symptomatic, with commercial immunoglobulin preparations containing neutralizing antibodies to human parvovirus
• Prevention and control involve good hygienic practices, such as hand washing and not sharing drinks

Herpes Labialis

• Characterized by crops of vesicles, usually at the mucocutaneous junction of the lips or nose
• Recurrences frequently reappear at the same site
• Clinical findings: keratoconjunctivitis and encephalitis
• Treatment options:
• Acyclovir: shortens duration of lesions and reduces viral shedding
• Penciclovir or docosanol: for recurrences of orolabial HSV-1
• Valacyclovir and famciclovir: for genital herpes and suppressing recurrences

Varicella-Zoster Virus (VZV)

• Clinical features of chickenpox (primary infection):
• 90% of cases occur before age 10, with a peak incidence between 2-8 years
• Virus entry through inhalation, replicates in respiratory tract, and invades lymph nodes
• Incubation period: 14-18 days

Epstein-Barr Virus (EBV)

• Structure: DNA virus, enveloped
• Etiologic agent of infectious mononucleosis and African Burkitt's Lymphomas
• Cultured in lymphoblastoid cell lines derived from B lymphocytes of humans and higher primates
• EBV can be cultured from saliva, and infection is acquired by contact
• Reservoirs include birds, pigs, and monkeys

Pathogenesis

• Virus is injected into the capillary circulation through an infected vector bite
• Virus comes into contact with susceptible target cells, such as endothelial cells, monocytes, and macrophages
• Replication in endothelial cells and reticuloendothelial cells leads to secondary viremia, infecting target organs like the brain, skin, musculature, and liver

Influenza Virus

• Viral structure: ssRNA, negative sense, 7-8 segments, 10 genes, spherical, enveloped
• Hemagglutinin and neuraminidase are surface glycoproteins
• Treatment options:
• Zanamivir/Oseltamivir
• Adamantanes

Classification

• Antigenic differences in internal structural proteins (NP and M) classify influenza viruses into types A, B, and C
• Surface glycoproteins (HA and NA) are used to subtype viruses
• HA and NA are variable and responsible for immunity to infection
• 15 subtypes of HA (H1-H15) and 9 subtypes of NA (N1-N9) have been recovered from birds, animals, and humans

Human Cancer Viruses

• At least 15% of all human tumors worldwide have a viral cause
• Two significant examples worldwide are cervical cancer and liver cancer

This quiz covers the use of Remdesivir and Paxlovid in treating COVID-19 patients. Learn about the FDA approved antiviral drugs for hospitalized patients and those with mild-to-moderate symptoms.