outbreak: a forensic identification of the causative agent of disease

Outbreak: A Forensic Identification of the Causative Agent of Disease.

Ebola, West Nile and the Flu, Oh My!!!

Mark A. Gallo, Associate Professor of Biology, Niagara UniversityChair, K12 Education, American Society for Microbiology

mgallo@niagara.edu

Same postulates used today when discussing infectious disease-causing agents(with some changes to the rules).

An estimated one third of the world's population (or ≈500 million persons) were infected and had clinically apparent illnesses during the 1918–1919 influenza pandemic. Case-fatality rates were >2.5%, compared to <0.1% in other influenza pandemics. Total deaths were estimated at ≈50 million and were arguably as high as 100 million.

The impact of this pandemic was not limited to 1918–1919. All influenza A pandemics since that time, and indeed almost all cases of influenza A worldwide (excepting human infections from avian viruses such as H5N1 and H7N7), have been caused by descendants of the 1918 virus, including "drifted" H1N1 viruses and reassorted H2N2 and H3N2 viruses. The latter are composed of key genes from the 1918 virus,updated by subsequently incorporated avian influenza genes that code for novel surface proteins, making the 1918 virus indeed the "mother" of all pandemics.

People don’t really have much intimate contact with pigs, do they???

Yuck, surely this is some sort of fluke, or is it?

Maybe it’s just a redneck thing?

Maybe it’s just a guy thing?

Nope, I guess not

National Center for Biotechnology Informationhttp://www.ncbi.nlm.nih.gov

National Center for Biotechnology Informationhttp://www.ncbi.nlm.nih.gov

NCBI data regarding influenzahttp://www.ncbi.nlm.nih.gov/genomes/FLU/

Growth in amount of nucleic acid sequence related to flu.

Anybody want to analyze their relatedness by hand?

What does the H meanAnd why do they cluster this way?

Antigenic Shift

Antigenic Drift

A few questions to consider:

Are sub-types always more similar sequence-wise?

Are certain influenza sub-types animal-host-specific?

Does country of origin matter with respect to relatedness of viruses?

Does year of appearance matter with respect to relatedness of viruses?

Does animal host matter with respect to relatedness of viruses?

Are certain viral genes always linked?

Do certain combinations of genes make for a more deadly strain of virus?

Has drift changed the genes sufficiently that they should receive a new sub-type?

http://www.cdc.gov/flu/weekly/WeeklyFluActivityMap.htm

Test your skill at ASM’s Microbelibrary.

AuthorsSanja SafticBerna Biotech.AGBern, Switzerlandsanja.saftic@bernabiotech.com

Matthias Ambergnothing medialab LtdBern, Switzerland

Renzo Haettenschwielernothing medialab LtdBern, Switzerland

Bastiaan Van Roodennothing medialab LtdBern, Switzerlandspot@nothing.ch

http://www.microbelibrary.org/asmonly/details.asp?id=1814&Lang=

Don’t forget to cover your sneezes!

Some web sites of interest

Centers for Disease Control and Prevention main 2009 Flu sitehttp://www.cdc.gov/h1n1flu/

Interactive weekly activity map of flu virus, both in terms of numbers of infections and deaths.http://www.cdc.gov/flu/weekly/WeeklyFluActivityMap.htm

Public Health Image Library - contains photos, drawings, illustrations, and multimedia fileshttp://phil.cdc.gov/phil/home.asp

MicrobeLibrary Visual Collection - contains a number of images, animations, and videos pertaining to microbiologyhttp://www.microbelibrary.org/about/index.asp?bid=1088

Flu game - A fast action Flash animation where individuals race the clock to vaccinate the population before the flu strikes them. Offered by the American Society for Microbiology.http://www.microbelibrary.org/microbelibrary/files/ccImages/Articleimages/saftic/index.html

Microbial Discovery Activitieshttp://www.asm.org/index.php?option=com_content&task=view&id=90592&Itemid=520

*Free on-line resource.*Submitted by teachers and microbiologists.*Peer-reviewed by ASM *Field tested exercises.*Inquiry-based and multidisciplinary. *Aligned with National Science Education Standards.*When used, biological agents do not exceed CDC’s biosafety standards level 1.*All include a printable teacher and student handouts.

Th-th-th-that’s all folks.