Title [TRANS] Respiratory Viruses.pdf ✅

Adenoviru s -complex DNA virus -70-80nm -genus Mastadenovirus -51 serotypes -icosahedral shell of 20 equilateral triangular faces and 12 vertices -capsid w/ hexon subunits w/ group specific and type - specific antigenic determinants same thing with its fiber (which has a knob) -6 subgenera (A-F) base on homology of DNA genomes -adenovirus genome is linear double -stranded DNA -replicative cycle result in either lytic infection or latent infection (lymphoid cells) -some induce oncogenic transformation in rodents only -affect mostly infants and children -throughout year but common in fall to spring -account for 10% of respi illnesses in civilian adults -nearly 100% of adults have serum antibody to multiple serotypes (thus common in childhood) -Types 1,2,3,5 are most frequent in children -types 4 and 7, also 3, 14, 21: associated with outbreaks of ARDS in military recruits in winter and spring TRANSMISSION -inhalation of aerosolized virus, by inoculation of virus into conjunctival sac -fecal-oral route -type-specific antibody generally develops after infection and associated with protection against same serotype infection --------- In children -variety of clinical syndromes; mostly is acute URT infection w/ prominent rhinitis -occasionally, LRT dse -types 3 and 7 cause pharyngoconjunctival fever in acute febrile illness in children on summer camps (bilateral conjunctivitis w/ bulbar and palpebral conjunctivae have granular appearance); low -grade fever for 3 -5 days, sore throat, cervical adenopathy – 1 -2 wks illness and resolves spontaneously -also associated is febrile pharyngitis w/o conjunctivitis -isolated from whooping w/ or w/o brodetela pertussis In adults -mostly ARDS by types 4 and 7 in military recruits – prominent sore throat and gradual onset of fever (reaching 39 C) on 2nd or 3rd day; cough, coryza, and regional LAD -PE: pharyngeal edema, injection, and tonsillar enlargement w/ little or no exudate -if pneumonia: patchy infiltrate in x -ray -associated w/ non -respi tract dse: diarrhea, hemorrhagic cystitis by types 11 and 21; epidemic keratoconjunctivitis by types 8,19, and 37 -its nucleic acids detected in myocardial cells from px w/ idiopathic myocardiopathies -suspected in epidemiologic setting of ARDS -mostly can’t differentiate with others and mycoplasma pneumonia -definitive dx: tissue culture w/ evidence of cytopathic changes and by immunofluoresnce or other immunologic techniques -rapid viral dx: ELISA of nasopharyngeal aspirates, conjunctival or respi secretions, urine or stool -PCR: highly sensible and specific -types 40 and 41: associated with diarrheal dses in children requiring isolation via tissue culture -Serum antibody rises can be demonstrated by complementfixation or neutralization tests, ELISA, radioimmunoassay, or (for adenoviruses that hemagglutinate red cells) hemagglutination inhibition tests -only: symptom - based tx and supportive therapy -antiviral therapy is not established -Ribavirin and cidofovir have activity in vitro against it; use in disseminated infections but not definitely -types 4 and 7: live vaccines used in control among military recruits ( live, unattenuated virus administered in enteric -coated capsules. ) - Infection of the gastrointestinal tract with types 4 and 7 does not cause disease but stimulates local and systemic antibodies that are protective against subsequent acute respiratory disease caused by those serotypes -program to redevelop type 4 and 7 vaccines is underway -also studied as live -virus vectors for delivery of vaccine antigens for gene therapy