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Artificial active immunity is the foundation for vaccination . It involves the activation of adaptive immunity through the deliberate exposure of an individual to weakened or inactivated pathogens, or preparations consisting of key pathogen antigens.

Table titled mechanism of Acquisition of Immunity. Passive and Natural: Immunity acquired from antibodies passed through breast milk or placenta. Passive and Artificial: Immunity gained through antibodies harvested from another animal. Active and Natural: Immunity Gained through illness and recovery. Active and Artificial: Immunity gained through a vaccine.
The four classifications of immunity. (credit top left photo: modification of work by USDA; credit top right photo: modification of work by “Michaelberry”/Wikimedia; credit bottom left photo: modification of work by Centers for Disease Control and Prevention; credit bottom right photo: modification of work by Friskila Silitonga, Indonesia, Centers for Disease Control and Prevention)
  • What is the difference between active and passive immunity?
  • What kind of immunity is conferred by a vaccine?

Herd immunity

The four kinds of immunity just described result from an individual’s adaptive immune system. For any given disease, an individual may be considered immune or susceptible depending on his or her ability to mount an effective immune response upon exposure. Thus, any given population is likely to have some individuals who are immune and other individuals who are susceptible. If a population has very few susceptible individuals, even those susceptible individuals will be protected by a phenomenon called herd immunity . Herd immunity has nothing to do with an individual’s ability to mount an effective immune response; rather, it occurs because there are too few susceptible individuals in a population for the disease to spread effectively.

Vaccination programs create herd immunity by greatly reducing the number of susceptible individuals in a population. Even if some individuals in the population are not vaccinated, as long as a certain percentage is immune (either naturally or artificially), the few susceptible individuals are unlikely to be exposed to the pathogen. However, because new individuals are constantly entering populations (for example, through birth or relocation), vaccination programs are necessary to maintain herd immunity.

Vaccination: obligation or choice

A growing number of parents are choosing not to vaccinate their children. They are dubbed “ antivaxxers ,” and the majority of them believe that vaccines are a cause of autism (or other disease conditions), a link that has now been thoroughly disproven. Others object to vaccines on religious or moral grounds (e.g., the argument that Gardasil vaccination against HPV may promote sexual promiscuity), on personal ethical grounds (e.g., a conscientious objection to any medical intervention), or on political grounds (e.g., the notion that mandatory vaccinations are a violation of individual liberties). Elizabeth Yale. “Why Anti-Vaccination Movements Can Never Be Tamed.” Religion&Politics , July 22, 2014. http://religionandpolitics.org/2014/07/22/why-anti-vaccination-movements-can-never-be-tamed.

It is believed that this growing number of unvaccinated individuals has led to new outbreaks of whooping cough and measles . We would expect that herd immunity would protect those unvaccinated in our population, but herd immunity can only be maintained if enough individuals are being vaccinated.

Vaccination is clearly beneficial for public health. But from the individual parent’s perspective the view can be murkier. Vaccines, like all medical interventions, have associated risks, and while the risks of vaccination may be extremely low compared to the risks of infection, parents may not always understand or accept the consensus of the medical community. Do such parents have a right to withhold vaccination from their children? Should they be allowed to put their children—and society at large—at risk?

Many governments insist on childhood vaccinations as a condition for entering public school, but it has become easy in most states to opt out of the requirement or to keep children out of the public system. Since the 1970s, West Virginia and Mississippi have had in place a stringent requirement for childhood vaccination, without exceptions, and neither state has had a case of measles since the early 1990s. California lawmakers recently passed a similar law in response to a measles outbreak in 2015, making it much more difficult for parents to opt out of vaccines if their children are attending public schools. Given this track record and renewed legislative efforts, should other states adopt similarly strict requirements?

What role should health-care providers play in promoting or enforcing universal vaccination? Studies have shown that many parents’ minds can be changed in response to information delivered by health-care workers, but is it the place of health-care workers to try to persuade parents to have their children vaccinated? Some health-care providers are understandably reluctant to treat unvaccinated patients. Do they have the right to refuse service to patients who decline vaccines? Do insurance companies have the right to deny coverage to antivaxxers? These are all ethical questions that policymakers may be forced to address as more parents skirt vaccination norms.

Questions & Answers

what is elements
Erneet Reply
an Element is a substance that can not be further decomposed by ordinary chemical means.
vannessa
can i get notes of biochemistry
Sneha Reply
yep why not
Abdullah
what is microbiology?
Gayanjali Reply
what is malaria
Gayanjali
bios- life/living things micro- small things that cannot be seen with the naked eye In other words the study of living things that cannot be seen with the naked eye but with the help of a microscope
Coltuneac
logos- science
Coltuneac
it is 10 to the power minus 6 biology which studies life forms on those scales including metabolism , physiology, nutrition requirements
barun
what are prokarytes
NDIMUKIKA Reply
A prokaryotic is a unicellular organanism that lacks a membrane bound nucleus ,mitochondria or other any membrane bound organelle. .......
Maryam
in prokaryotic nucleus is not developed and cell organelles are absent
Harshad
how is one who is feeling blockage in the chest with mucus be diagnosed
Essy Reply
be talking sepitol every morning
Ikenna
is that all?
Ven.phumie
What is prions
Sangeeta Reply
is tuberculosis a viral infection?
hildar Reply
No. It is a Bacterial Infection.
Orooj
what are zn staining
Evelyn Reply
full meaning zeil neelson staining
kezia
By using zn stain we diagnose / examine acid fast bacilli .
Deepak
explain hw bacteria grows
Kanyago Reply
Hw does bacteria grow?
Kanyago
Binary fission
Sangeeta
three successive phase comes in bacteria growth i.e lag phase/adaptation phase ,log phase/exponential phase ,death phase when it is in fermentation process .
Deepak
introduction to virology
Dongyile Reply
is the study of virus
FADAYOMI
Virology
Sangeeta
study of virus which can be seen by using electron microscope i.e below 1micron in size . It requires a host cell to multiply own number to proliferate itself .
Deepak
what are some five benefits of studying microbiology
Joyce Reply
please I'm waiting for answers
Joyce
microbio is very important! 1.) microbes thought to have evolved into our cells 2.) they keep us healthy 3.) they can cause disease and illness 4.) good for bioremediation 5.) show evolution in real time(observable) 6.) make the earth a liveable place (make more o2 than plants)
just
What fields are interesting to study when you are doing your postgraduate degree
Noxolo
what is mean by killed vaccine?
Nasira Reply
Heat or formaldehyde inactivated live strain
Number
what is an antimicrobial
Denis Reply
what are eukaryotes
Oenen Reply
a eukaryote is an organism whose cells contain complex structures enclosed within membranes .
Dipali
has a nucleus. prokaryotes don't have a true nucleus.
Tanisha
they are micro-organisms with complex structure or have a nuclear membrane
Irene
It has true nucleus
Sangeeta
how many protons,electrons and neutrons are there in a matter
Y'NOTS Reply
this would depend what matter you're looking at, on top of other variables such as isotopes and isomers. can we have a better picture of what you're trying to identify
Nicolas
Practice MCQ 2

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Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
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