Video: Microbial diseases part 2 - Viruses

Vocabulary flashcards covering key virus families, diseases, vaccines, diagnostics, and clinical features from the lecture notes.

Paramyxoviridae

Enveloped, negative-sense ssRNA, linear, non-segmented virus family that includes measles (Rubeola) and mumps; surface glycoproteins mediate attachment and entry (H and F for measles; HN and F for mumps).

Rubeola (Measles) virus

Paramyxoviridae, negative-sense ssRNA, highly contagious; causes measles with fever, cough, coryza, conjunctivitis, Koplik spots, and a cephalocaudal rash.

Mumps virus

Paramyxoviridae, negative-sense ssRNA; causes parotitis; transmitted via respiratory droplets/aerosols with public health implications.

Matonaviridae

Enveloped, positive-sense ssRNA virus family that includes Rubella; linear, non-segmented with surface glycoproteins (E).

Rubella virus

Matonaviridae, positive-sense ssRNA; causes rubella; congenital rubella syndrome; vertical transmission to fetus.

Picornaviridae

Non-enveloped, icosahedral capsid, positive-sense ssRNA; includes Coxsackievirus; typically enteric transmission.

Coxsackievirus

Picornaviridae; serotypes A and B; causes hand, foot, and mouth disease (HFMD) and herpangina; spread via fecal-oral and respiratory routes.

Molluscum contagiosum virus (MCV)

Poxviridae; enveloped dsDNA; brick-shaped virions; replicates in cytoplasm; causes painless, umbilicated skin lesions; self-limited in immunocompetent individuals.

Parvovirus B19

Parvoviridae; non-enveloped ssDNA; binds P antigen on erythroid progenitors; causes erythema infectiosum (slapped-cheek), can cause aplastic crisis and fetal infection.

Herpesviridae

Enveloped dsDNA viruses; replicate in the nucleus; exhibit latency and reactivation; lifelong infections with variable symptoms.

Herpes Simplex Virus 1 (HSV-1)

Latency in trigeminal ganglia; causes orofacial lesions (cold sores); can cause gingivostomatitis; transmitted via saliva.

Herpes Simplex Virus 2 (HSV-2)

Latency in sacral/pelvic ganglia; causes genital herpes; neonatal risk; can have asymptomatic shedding.

Varicella Zoster Virus (VZV)

Herpesviridae; enveloped dsDNA; causes varicella (chickenpox) as primary infection and zoster (shingles) upon reactivation; vesicular rash in stages.

Roseola virus (HHV-6/HHV-7)

Human herpesviruses 6 and 7; cause roseola (sixth disease); high fever followed by a pale pink exanthem; may cause febrile seizures.

Poxviridae

Large, brick-shaped enveloped dsDNA viruses; replicate in the cytoplasm and encode their own DNA-dependent RNA polymerase; includes Molluscum contagiosum.

MMR vaccine

Live, attenuated vaccine against measles, mumps, and rubella; first dose at 12–15 months, second dose at 4–6 years; MMRV includes varicella.

Koplik spots

Small bluish-white spots on buccal mucosa seen in measles before the rash appears.

Forchheimer spots

Petechiae on the soft palate seen in rubella.

Congenital Rubella Syndrome

Birth defects from maternal rubella infection: patent ductus arteriosus, heart defects, eye and hearing abnormalities.

Subacute Sclerosing Panencephalitis (SSPE)

Fatal chronic brain inflammation years after measles infection.

Syncytia

Multinucleated giant cells formed by viral-induced cell fusion (notably in measles and other paramyxoviruses).

Hemagglutinin (H/HN) and Fusion (F) proteins

Viral surface glycoproteins: H/HN mediate attachment; F mediates fusion of viral and cellular membranes; key for entry.

Acyclovir

Guanyosine analog antiviral activated by viral kinases; inhibits viral DNA polymerase; used for HSV and VZV infections (topical, oral, IV).

Valacyclovir

Prodrug of acyclovir with greater oral bioavailability; used for HSV and VZV; convenient dosing.

Shingrix

Recombinant glycoprotein E vaccine for herpes zoster (shingles); approved for adults ≥50 or immunocompromised; non-live vaccine.

Varivax

Varicella vaccine (live attenuated); two-dose series for children and adults without immunity.

Zoster (Shingles)

Reactivation of VZV in a dermatomal distribution; painful vesicular rash that may involve eye or ear; treated with antivirals.

Hand, Foot, and Mouth Disease (HFMD)

Coxsackievirus (A and B) infection; fever, mouth ulcers, and vesicular rash on hands, feet, and sometimes buttocks.

Herpangina

Coxsackievirus infection causing painful oropharyngeal ulcers and fever; common in children.

Erythema Infectiosum (Fifth Disease)

Parvovirus B19 infection with 'slapped-cheek' facial rash and reticular body rash; may cause aplastic crisis in some patients.

Slapped Cheek syndrome

Another term for erythema infectiosum (Parvovirus B19) presenting with bright red cheeks.

Nagayama spots

Erythematous papules on the mucosa of the soft palate seen in roseola (HHV-6/7) infection.

Molluscum contagiosum Henderson-Paterson bodies

Histologic inclusion bodies in Molluscum contagiosum lesions; large eosinophilic cytoplasmic inclusions in infected keratinocytes.

Vertical transmission

Transmission of infection from mother to fetus across the placenta; a concern in rubella during pregnancy.

Measles post-exposure prophylaxis (PEP)

MMR vaccine within 72 hours of exposure or immune globulin within 6 days for high-risk individuals to prevent or lessen measles.

Varicella rash description 'dew drop on a rose petal'

Varicella lesions: clear vesicles on an erythematous base in multiple stages, resembling dew drops on a rose.

Measles rash progression

Rash begins at the hairline and spreads cephalocaudally over 3–4 days (measles).

Rubella rash progression

Rash begins on the face and spreads to the trunk and extremities, typically milder and shorter than measles.