Immuno Notes

2 Pages

Microbiology and Immunology
Course Code
Microbiology and Immunology 2500A/B
Kelly Summers

This preview shows 80% of the first page. Sign up to view the full 2 pages of the document.
Introduction – Jan. 7 - Infectious disease is the major cause of human mortality throughout history. Major increases in life expectancy from the early 1900s onward were mainly due to control of infectious diseases. Life expectancy is highest in North America, Europe, and Australia. Of the top 10 causes of death in high- income countries, only one is from infectious disease (lower respiratory infections). In low-income countries, lower respiratory infections, diarrhoeal diseases, HIV/AIDS, malaria, TB, and neonatal infections are all infectious diseases found in the top 10 causes of death. - Do infectious agents evolve to become more virulent?: There are multiple possible outcomes when a population is infected by a new infectious agent – 1. The host’s immune system overwhelms the agent. 2. The agent overwhelms and kills the host without being transmitted. 3. The agent replicates within the host and is transmitted to a new host. The host may die or recover. New infections may produce a high death rate, but over the course of time, the host and agent adapt to one another and the disease normally becomes less virulent. - Epidemiology of infectious disease: Endemic – When an infectious disease is continuously present. There is a continuous supply of new hosts. In smaller populations a disease cannot find sufficient new hosts. Epidemic – When new cases of a disease substantially exceed what is expected. Populations lack sufficient immunity to an infectious agent. Pandemic – An epidemic on an inter- country or inter-continental scale. HIV is an epidemic because it is still increasing. - Human-microbe relationships: Parasitic – Relationship between two species in which one benefits (parasite) from the other (host). It usually involves some detriment to the host. Commensal – Relationship between two species in which one is benefited and the other is not affected, neither negatively nor positively. Mutualistic – Relationship between two species where both benefit. - The microbiota: Modern medicine has studied microbes as perpetrators of disease. However, the vast the majority of microorganisms are not pathogenic. In humans, there are - resident microorganisms and they are termed the microbiota. They are mostly concentrated in the gastrointestinal tract. There are more than 1000 different species and most have not been cultivated. We have more bacteria in our bodies than human cells. - The human microbiota: Internal organs are usually sterile. Surface tissues (external) have extensive populations of microbes. The collective genome of the human microbiota (the microbiome) contains more than 100 times as many genes as our own genome. Som
More Less
Unlock Document

Only 80% of the first page are available for preview. Some parts have been intentionally blurred.

Unlock Document
You're Reading a Preview

Unlock to view full version

Unlock Document

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.