<< Chapter < Page Chapter >> Page >
a) Painting of Edward Jenner. B) Photo of many red lumps on the skin.
(a) A painting of Edward Jenner depicts a cow and a milkmaid in the background. (b) Lesions on a patient infected with cowpox, a zoonotic disease caused by a virus closely related to the one that causes smallpox. (credit b: modification of work by the Centers for Disease Control and Prevention)
  • What is the difference between variolation and vaccination for smallpox?
  • Explain why vaccination is less risky than variolation.

Classes of vaccines

For a vaccine to provide protection against a disease, it must expose an individual to pathogen-specific antigens that will stimulate a protective adaptive immune response. By its very nature, this entails some risk. As with any pharmaceutical drug, vaccines have the potential to cause adverse effects. However, the ideal vaccine causes no severe adverse effects and poses no risk of contracting the disease that it is intended to prevent. Various types of vaccines have been developed with these goals in mind. These different classes of vaccines are described in the next section and summarized in [link] .

Live attenuated vaccines

Live attenuated vaccines expose an individual to a weakened strain of a pathogen with the goal of establishing a subclinical infection that will activate the adaptive immune defenses. Pathogens are attenuated to decrease their virulence using methods such as genetic manipulation (to eliminate key virulence factors) or long-term culturing in an unnatural host or environment (to promote mutations and decrease virulence).

By establishing an active infection, live attenuated vaccines stimulate a more comprehensive immune response than some other types of vaccines. Live attenuated vaccines activate both cellular and humoral immunity and stimulate the development of memory for long-lasting immunity. In some cases, vaccination of one individual with a live attenuated pathogen can even lead to natural transmission of the attenuated pathogen to other individuals. This can cause the other individuals to also develop an active, subclinical infection that activates their adaptive immune defenses.

Disadvantages associated with live attenuated vaccines include the challenges associated with long-term storage and transport as well as the potential for a patient to develop signs and symptoms of disease during the active infection (particularly in immunocompromised patients). There is also a risk of the attenuated pathogen reverting back to full virulence. [link] lists examples live attenuated vaccines.

Inactivated vaccines

Inactivated vaccines contain whole pathogens that have been killed or inactivated with heat, chemicals, or radiation. For inactivated vaccines to be effective, the inactivation process must not affect the structure of key antigens on the pathogen.

Because the pathogen is killed or inactive, inactivated vaccines do not produce an active infection, and the resulting immune response is weaker and less comprehensive than that provoked by a live attenuated vaccine. Typically the response involves only humoral immunity, and the pathogen cannot be transmitted to other individuals. In addition, inactivated vaccines usually require higher doses and multiple boosters, possibly causing inflammatory reactions at the site of injection.

Questions & Answers

what is parasite
Abdirizack Reply
designing of aseptic area
Aashish Reply
I don't know
Abdirizack
what is rickettsia
DENNIS Reply
what is microbiology
Erasto
Is the science that works with microorganisms.
Rose
richettsa is small microorganisms that cause disease in human like typhus; they are like viruses that can grow only inside living cells, they're transmitted by mites, ticks or lices.
Rose
what is plasmid?
mavis
plasmid is extra chromosomal body present in bacteria...which have additional genetic functions example... antibiotic resistance genes....etc etc
Chaitanya
state the theory of spontaneous generation of micro oranisms and germ theory of disease
UKAMAKA Reply
what are the advantages of high note numerical aperture
Genius Reply
list if non flagellated pritozoa
Mepung Reply
Can someone that's understanding of the Kreb Cycle please explain & breakdown it down to me in the simplest way without giving me the dictionary version or Google version. Basically in there own words of knowledge....!
Kisha
ok
lucas
please can someone help explain positive and negative feedback in simple term
Gum
negative feedback is the arresting of reaction or reverse of the reaction according to the response and postive feed back is the direct response without reversing or arresting a reaction.
Greet
OK
umar
pls can someone explained Kinney stone in memorising in shot time
umar
what tyoebif microorganism will be killed by antibiotic trwatmeant
Mary Reply
I don't really don't understand aerobic respiration anaerobic respiration and fermentation. Can someone explain & breakdown this in the simplest way please.
Kisha
Anaerobic Respiration in which foodstuffs are partially oxidized, with the release of chemical energy, in a process not involving atmospheric oxygen, such as alcoholic fermentation, in which one of the end products is ethanol.
Muhammad
aerobic respiration A type of respiration in which foodstuffs are completely oxidized to carbon dioxide and water, with the release of chemical energy, in a process requiring atmospheric oxygen.
Muhammad
please can someone explain what pseudomonas species and biofilm is?
uju
Fermentation is the growth of cells or microorganisms in bioreactors (fermenters) to synthesize special products. Fermentation in biochemistry refers to the biodegradation of carbon compounds by cells or organisms under anaerobic (lack of oxygen) conditions.
Muhammad
Please under which conditions does pathogens become established in the human tissues and can cause diseases
Atambilla
please the life cycle of plasmodium parasite
mavis
who is John Needham
Mary Reply
John Needham is one of the researcher in microbiology. He also experimented when scientists did not believe animals could arise spontaneously ,but did believe microbes could.
Gum
okay is he late
Mary
by the way what are the list of courses offered by a newly admitted student for microbiology
Mary
Needham's experiments with beef gravy and infusions of plants material reinforced this idea.
Gum
what drugs are given to a person with Otis nerve problem(ear problem)
Gum Reply
good morning to you all.
Muhammad Reply
Dr.A.K.S.P.G. college Akbarpur Ambedkar Nagar
Rajan
Shailesh Vishwakarma BSc 1st year
Rajan
differentiate between eukaryotes en prikaryotes
AKANKWATSA Reply
eukaryotes are organisms with complex cellular structure(presence of nucleus and mitochondrial) like plants and animals whilst prokaryotes are organisms with simple cellular structure (absence of nucleus, mitochondrial) like arthropods.
Seidu
hlo
Shagufta
hii
dr
hello sir
pankaj
I am Pankaj from bihar
pankaj
I am study in NDRI karnal in btech in dairy
pankaj
I am Pankaj from bihar
pankaj
thanks am studying biomedical sciences in zambia.chikankata
Sharon
Am a studying Disease Control in Ghana(kintampo)
Seidu
I'm studying Environmental health in Zimbabwe 🇿🇼
trust
am Joyce mwale studying nursing in Lusaka Zambia
Joyce
hi pankaj
Shailesh
hi frds iam from India
Nevil
IAM studying degree (micro biology)
Nevil
Hi I am microbiologist
Muhammad
Hi friends I'm from Nigeria studying Microbiology
uju
i am biotechnologist from pakistan
Saddam
hi feds iam from india
Shibanjan
hi
Krishna
india
Krishna
hy frnds am from Uganda
AKANKWATSA
am studying nursing/midwifery n kampala
AKANKWATSA
I'm Gum Joseph Kakuu from Ghana,I'm studying RGN in nursing Jirapa.
Gum
I'm Hellen from Kenya studying applied biology
Hellen
I live in india
Krishna
am studying biotechnology
Krishna
am maryjoy uwaoma from Nigeria,I am studying microbiology in NSUKKA NIGERIA
Mary
Nice meeting You people hear
Seidu
thanks you.
Gum
can someone in there own words in the simplest way breakdown what aerobic respiration anaerobic respiration and fermentation means please and not from the dictionary version...!
Kisha
what are the cultivation and identification of microorganisms
Algel Reply
ransport media.basic culture media.enriched media..differential media .indetification media
AKANKWATSA
algel th above are some v th basic medias for bacterial growth
AKANKWATSA
factors that can Prone the host to get disease
Linda Reply
what are the factors that prones host to get disease
Linda
HELLO
Hashim
Not sure about it, can you tell us Linda?
KINGSFORD
please I want to know the factors that prones host to get disease
Linda
please Linda we have internal and external factors. internal factors are within our body cavities.eg mother having TB giving it to her child,and the others. external factors are within our surrounding environment which include our daily activities(bathing, buying food and the others)
Gum
I don't understand aerobic respiration anaerobic respiration and fermentation. Can someone that do give me a short & simple breakdown.
Kisha
pliz kisha ..aerobic respiration is th typ v repiration whre organisms use oxgyen for survival while anaerobic respiration is whre organisms survive without oxgyen at all.these use carbondioxide
AKANKWATSA
Guys pls answer me this question fast... What are the purpose of infection prevention in 50 words..
RAPHERA Reply
The purpose of infection and prevention is a scientific approach and practical solution designed to prevent harm cause by infection to Pt and health worker
what is the sequence of kingdom concept?
isha Reply
what is immunity
Algel
what are the classification and identification of microorganisms
Algel
whats anatomy
abdiqani
and physiology
abdiqani
anatomy is the study of the human structure
physiolog is the study of the human body function
Anatomy and physiology is the study of the human body parts and their functions.
Kwame
who's the father of Microbiology
The definition you gave is not for the two
Samuel
leeuwenhoek is the real father of microbiology
abdiqani
anatomy is the study of the structure and relationship between body part while Physiolog is the study of the function of body part
thats real definition
abdiqani
I am sure about Louis pasteur been the real father of microbiology
Mary
microbiology father is marcelo
DENNIS
sorry the father is Anthony Van Leeuwenhoek
DENNIS
The father is Marcello Malpighi
DENNIS
Anatomy and physiology is the study of the body structures and how they relate to each other
Unbeatable
Practice MCQ 2

Get the best Microbiology course in your pocket!





Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Microbiology' conversation and receive update notifications?

Ask