Adenovirus

William Cheng

Argelia Torres

Michelle Wittig

Overview of Presentation

• Review– Classification, Morphology, Physical

Properties

• Presentation of Case Study– Symptoms and Syndrome– Sources and Transmission– Tests, Prevention and Treatment

Classification

Family Adenoviridae– Genus Aviadenovirus

• Infect birds only

– Genus Atadenovirus• Broad range of species

– Genus Mastadenovirus• Infect mammals only

– Genus Siadenovirus• Infect frogs and turkeys

Morphology

• Linear DS DNA Virus• No Envelope• Iscosahedral

symmetry• 252 capsomers, with

12 vertices.– 12 Filaments

protrude from penton bases

Physical Properties

• The thermal inactivation point is at 56°C

• Under in vitro conditions virions are stable when stored at -20°C

• Stable in acid environment of pH 5-6

• Virions are not sensitive to treatment with lipid solvents.

• All of the above allow for prolonged survival outside of the host body

Endocytosis• Adenovirus attachment mediated by

the fiber which binds a specific receptors

• Virus migrates to clathrin coated pits to form a receptosome and become internalized

• Virus capsid proteins broken down in the endosome (lower pH).

• Viral core and some capsid proteins associate with microtubules in the cytoplasm and allows the viral DNA to enter the nucleus through nuclear pores

• Nucleus is the site of mRNA transcription and DNA replication

Case Study

• A 7-year-old boy attending summer camp complains of sore throat, headache, cough, red eyes, and tiredness and is sent to the infirmary. His temperature is 40° C. Within hours other campers and counselors visit the infirmary with similar symptoms that last 5-7 days. All of he patients have gone swimming in the camp pond. More than 50% of the people in the camp complain of symptoms similar to the original case. The public health department identifies the agent as adenovirus serotype 3.

SymptomsFever of 104FHeadache Red eyes

Cough

Sore throat

Tiredness

Adenovirus Syndrome

• There are 49 distinct types of adenovirus. Serotype 3 and 7 are known for causing pharyngoconjunctival fever from summer camps and swimming pools. Symptoms include high fever lasting 4-5 days, pharyngitis (sore throat), conjunctivitis (pink eye - inflamed, red eyes), enlarged lymph nodes, headache, malaise and weakness.

• Since in our case study the child acquired this illness from the camp pond and has had the week long fever as well as sore throat, red eyes, head ache, and tiredness. All symptoms point to pharyngoconjunctival fever.

Likely Source of InfectionCamp Pond

The most likely source of infection was the camp pond. All of the patients had gone swimming there and they all had similar symptoms as the boy with the adenovirus type 3 infection.

Adenovirus infections such as pharyngoconjunctival fever are characterized by febrile disease (fever) and conjunctivitis (red eye) like in this case study and are normally associated with waterborne transmission. These types of adenoviruses can be found in inadequately chlorinated swimming pools and small lakes.

Likely Routes of Transmission

In general can be transmitted: In this case the three most likely routes: *direct contact *water contact *fecal-oral transmission *fomite *occasionally waterborne transmission *person-to-person

Since most likely the pond water was contaminated the route of entry into the host may have been through direct contact with the eyes (conjectiva), nasopharynx, and mouth. In addition to direct contact with contaminated pond water sharing of contaminated towels, contact with contaminated surfaces such as doorknobs and faucet handles could help further spread the virus. Coughed-out droplets from an infected person can also help spread the virus onto surfaces and to others.

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Prevention

• Normal hand washing and sanitary practices• Chlorination of the water

– Drawback with chlorinating the pond comes from the fact that soil-bottom reservoirs are usually very turbid. The chlorine will react with organic molecules to form trihalomethanes such as chloroform, which are useless for virus protection. In addition, the virus can attach itself to particles in the water and remain viable in the water for long periods of time.

• Monitoring the microbiological quality of the water

Samples

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Throat swab sample

Pond water sample Eye secretion sample

Sputum sample

Lab Tests

Direct antigen detection by immunofluorescence

Polymerase Chain Reaction

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Lab Tests

Hemagglutination-inhibition assay

Positive

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Treatment

• Most infections are mild and require only treatment of observed symptoms.

• There is no virus-specific therapy, serious adenovirus illness can be managed only by treating complications of the infection.

• Deaths are rare but have been reported.

References• Boone, S. A., & Gerba, C. P. (2007, March). Significance of fomites in the spread of respiratory and enteric viral disease. Applied and

environmental microbiology, 73(6), 1687-1696. Retrieved November 25, 2007, from http://www.pubmedcentral.nih.gov/picrender.fcgi?tool=pmcentrez&artid=1828811&blobtype=pdf.

• CDC (1992, May 15). Outbreak of Pharyngoconjunctival Fever at a Summer Camp—North Carolina, 1991. MMWR: Weekly, 41(19), 342-344. Retrieved November 24, 2007, from http:// www.cdc.gov/mmwr/preview/mmwrhtml/00016704.htm

• CDC (2005, January 21). Adenoviruses. Retrieved November 24, 2007, from http://www .cdc.gov/ncidod/dvrd/revb/respiratory/eadfeat.htm.

• Dr. Hull’s Encyclopedia Index. Pharyngoconjunctival fever. Retrieved November 26, 2007 from http://www.drhull.com/EncyMaster/P/pharyngoconjunctival_fever.html

• Giladi, N., & Herman, J. (1984). Pharyngoconjunctival fever. Archives of Disease in Childhood, 59(12), 1182-1183. Retrieved November 24, 2007, from http://adc.bmj.com/cgi/ content/abstract/59/12/1182 (q5. adenovirus 3 isolated from pharynx).

• Haggerty, M. (2007). Adenovirus infections: diagnosis. Retrieved November 25, 2007, from http://www.answers.com/topic/adenovirus-infections-diagnosis.

• Health Encyclopedia. Adenovirus infections. Retrieved November 27, 2007 from http://www.faqs.org/health/topics/12/Adenovirus-infections.html.

• International Committee on Taxonomy of Viruses. Adenoviridae. Retrieved November 26, 2007 from http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/01000000.htm.

• Klein, J. (2006, September). Adenovirus. Retrieved November 24, 2007, from http://www. kidshealth.org/parent/infections/lung/adenovirus.html

• National Center for Infectious Diseases. Adenoviruses. Retrieved November 25, 2007 from http://www.cdc.gov/ncidod/dvrd/revb/nrevss/eadfeat.htm.

• NSW Health. Fact Sheet: Epidemic Keratonconjuctivitis. Retrieved November 26, 2007 from http://www.health.nsw.gov.au/public-health/phb/HTML2006/novdec06html/article7p181.html.

• Rays Virology Page of University of Mississippi Medical Center. Adenovirus and human misery. Retrieved November 24, 2007 from http://micronet.im.ac.cn/vdu.old/adeno.htm.

• Thomas Jefferson University. Epidemiology of Adenovirus Infections. Retrieved November 26, 2007 from http://www.fda.gov/OHRMS/DOCKETS/AC/01/slides/3868s1_05_flomenberg/index.htm.

• UK clinical virology network (n.d.). How to perform virology tests. Retrieved November 25, 2007, from http://www.clinical-virology.org/pages/cvn/sp_gp/cvn_gp_how.html

• Zhang, Q., Su, X., Gong, S., Zeng, Q., Zhu, B.,Wu, Z., Peng, T., Zhang, C., & Zhou, R. (2006). Comparative genomic analysis of two strains of human adenovirus type 3 isolated from children with acute respiratory infection in southern china. Journal of General Virology, 87, 1531–1541. Retrieved November 24, 2007, from http://vir.sgmjournals.org/cgi/content/abstract/ 87/6/1531.

Thank You