How to make a vaccine: vaccination stategies
Natural: exposure to sub-clinical infections
Artifical: attenuated organisms, killed organisms sub cellular, toxins/toxoids, small fragments and DNA
Attenuation: the virulent parents virus becomes the LIVE attenuated vaccine.
- live is the ability to replicate in host cells
- Rabies now days are killed bacteria vaccine but when it was made in 1885 it was live.
Live attenuated vaccine
- the virus in the vaccine must be “alive”: to replicate in the vaccinee’s cells
Storage: OPV with vaccine vial monitor.
Maternal antibodies: Ab from the mom to the newborn before birth. The baby is born with
enough Ab to fight pathogens. Antibodies will stay 3-6months maximum. If your rejecting
measels vaccine, those Ab will kill vaccine and it will kill so that’s why vaccines are given after
6 months from the date of birth. This is why you wait 12 months
Risk for back mutation: keep in mind the risk. Stoped from using attenuated vaccine aganist
polio because there’s a chance that it will fight back. Smallpox vaccine is the same as before.
The attenuated virus can infect non vaccinated people
Better herd immunity (polio), its vaccinating not only you but those around you as well who
are exposed to the bacteria.
Risk to immuno-comprimised people (influenza). You don’t want old people to be exposed to
be attenuated vaccine WHY? . Use nasal sprays. They can be suspected to be influenza virus so
you avoid exposing them to attenuated virus. Pregnant women don’t get attenuated virus
because we don’t know how it will affect the baby.
18 and 12 month year old for chickenpox vaccine. When your 16, CDC vaccine with higher
The virus must be alive so it can replicate in your systems.
Live attenuated Vaccine
- MMR: measles, mumps & rubella
Affects babies during the first semester.
o Mumps: lead to complications. MMP vaccine for mumps isn’t that effective, measles
90% and rubella is high as well.
o Measeles: biggest problem. Virus that cause long term effects.
RNA viruses but genetically stable because the mutations reduce their ability to
No back mutation, safe vaccine for everybody.
Human host only. Measles killed a lot of people (look up some stats)
Influenza since 2003
For healthy and young
Using the drop to the mouth. Its to mimic the normal infection, the virus
goes to your stomach and hut moving towards the bladder.
POLIO SALK IS KILLED (recent one) Varicella Zoster (affects you in two parts of your life. Child and adulthood)
Chicken pox in kids
Get the vaccine atleast once to avoid shingles. You might even get some
boosters for chicken pox
Shingles in adults (>60years)
Killed and subcellular vaccines
- the virulent parental virus. For ex. Formalin deteregent leads to inactivated (killed) vaccine
- virions inactivated by chemical procedures. Its biological.
- infectivity and viral ability to replicate are eliminated but antigencitiy is not compromised.
- Polio (Salk)
At present: very common use because attenuated vaccine is casuing problems. 8/year is enough to
change the direction of the vaccination.
o new strain every year. You uses membranes out of the virus for the vaccine
o Virus that you get infected with contamination.
Modern rabies vaccine
o Killed vaccine
o Even post exposure in most cases.
o In rabies, viruses wants to live in the neurons and always transfer through neuronal cells.
o Out of the vaccination community
- bacterial proteins (enzymes)
- destroys host cellular structures
- A-B toxins:
A: active (virulent part) A can cause the damages
B: bindig, binding proteins that affects the cell surface.
- make vaccines that kill the binding site (B)
Modification of toxin to toxoid
- Active (A) and Binding (B) through chemical modification makes the A not active leaving the B
binding site there
- with genetic engineering, you can ONLY make the B or the binding protein and you inject that into the body
which will make Ab against the B
Toxoids: inactivated toxin
1) Diphtheria 2) Tetanus
- 35% in normal flora. In the bacteriophage, it can infect the bacteria. The bacteriophage isn’t destroy the
cell. It can intergrat ein the genome of the bacteria and stay there forever as long as the cells can replicate.
The bacteriophage can produce toxins against other others. Diphteria toxins created by the bacteriophage
causes the problem. Bacteriophage is responsible for human disease (virus bacteriophage)
- immunize every year
-hep.B makes proteins tat Ab can combine to
- when virus is infecting people it makes a lot of proteins. You can find those proteins in the blood that’s not
attached to anything. F
- Fractionation purified subunit vaccine
- the viulent parental virus cloning using yeast/bacterial cell either fractionation OR expression
purified subunit vaccine
Hep.B virus: a fragment virus
- Antigen: HBsAg
- first generation vaccine: extracted from the blood plasma of hepatitis patients.
- Today: cloned in yeast.
Hep.B can be prevented, the first vaccine against cancer
- Hep.B affects liver carcinoma, it is also a Kill vaccine
- made out of the cupsif of the vaccine, the genome is inside.
MMR and varcella should be careful because newborns are Ab from mo