Vaccine

Vaccine – Definition, Invention, Types, Classification and Uses

A vaccine is a biological preparation that improves immunity to a disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe, its toxins, or one of its surface proteins. When a person is exposed to the agent, the body’s immune system produces antibodies against the agent. If the person is later infected by the disease, these antibodies will recognize the disease agent and attack it, limiting the infection. Vaccines can be prophylactic, therapeutic, or both.

Classification of Vaccines

There are many types of vaccines, but they can be generally classified into two types: live attenuated and inactivated. Live attenuated vaccines contain a weakened form of the microbe that is used to stimulate immunity. Inactivated vaccines contain killed forms of the microbe. There are also subunit vaccines, which contain only specific proteins or polysaccharides from the microbe. Toxoid vaccines contain toxins that have been inactivated and are used to protect against toxoid-producing bacteria.

S.NO	CONTENT
1	INTRODUCTION
2	CLASSIFICATION
3	INVENTION
4	TYPES

Invention of Vaccine

Edward Jenner is credited with being the first person to develop a vaccine. In 1796, Jenner observed that milkmaids who had contracted cowpox, a milder relative of smallpox, were immune to smallpox. Jenner hypothesized that cowpox vaccine could protect people from smallpox. He tested his theory by vaccinating an 8-year-old boy with cowpox and then exposing him to smallpox. The boy did not get sick. Jenner then developed a vaccine using cowpox virus.

Types of Vaccines

There are many different types of vaccines, but most can be divided into two categories: live attenuated vaccines and inactivated vaccines.

Live attenuated vaccines are made from viruses or bacteria that have been weakened so they can’t cause disease. These vaccines are usually given by injection, but sometimes they are given by mouth. Live attenuated vaccines are very effective, but they can sometimes cause minor side effects, such as a fever or a rash.

Inactivated vaccines are made from viruses or bacteria that have been killed with heat or chemicals. These vaccines are usually given by injection. Inactivated vaccines are very safe and rarely cause any side effects.

A. Live Attenuated Vaccines:

A vaccine is a preparation that provides immunity against a particular disease. It is made from either weakened or killed forms of the virus, bacteria, or other organism that causes the disease. Vaccines are administered through a needle injection, nasal spray, or oral drops.

There are several different types of vaccines, but the most common are live attenuated vaccines. These vaccines use a weakened or killed form of the virus, bacteria, or other organism to provoke an immune response in the body. The immune response then protects against future infection by the virus, bacteria, or other organism.

Live attenuated vaccines are usually recommended over other types of vaccines because they are more effective and have fewer side effects. However, they are also more risky because they can cause the disease they are meant to prevent. For this reason, live attenuated vaccines are not recommended for people with weakened immune systems.

B. Inactivated Vaccine:

Inactivated vaccines are made from viruses, bacteria, or other organisms that have been killed with heat, chemicals, or radiation. They usually come in the form of a shot, and are used to prevent diseases such as polio, hepatitis A, and rabies.

C. Toxoid Vaccine:

A toxoid vaccine is a vaccine that uses an inactivated or killed form of a toxin to protect against that toxin. Toxoids are made from toxins that have been modified so that they are no longer harmful. The toxin may be from a bacteria or a virus.

The toxoid vaccine is given as an injection. It is usually given as a series of three or four doses, depending on the type of vaccine.

D. Subunit Vaccine:

A Sabin-type live attenuated poliovirus vaccine is available in the United States. This vaccine is made from three types of attenuated polioviruses. It is given as a single oral dose and is highly immunogenic.

The vaccine is 95% effective in preventing paralytic poliomyelitis. It is also effective in preventing VAPP.

The vaccine is contraindicated in persons with a history of poliomyelitis, immunosuppression, or allergy to any component of the vaccine.

The vaccine is available as a trivalent or quadrivalent vaccine. The trivalent vaccine protects against PV1, PV2, and PV3. The quadrivalent vaccine also protects against PV4.

E. Conjugate Vaccine:

A vaccine composed of a killed or weakened form of a pathogen, combined with a substance that stimulates the production of immunity in the body.

F. Valence Vaccine:

F. Valence is a vaccine for the prevention of meningococcal disease caused by serogroups A, C, W, and Y. The vaccine is a quadrivalent conjugate vaccine, which contains polysaccharides from the four serogroups. The vaccine is administered as a single dose intramuscular injection.

F. Valence is indicated for use in individuals 2 years of age and older. The safety and efficacy of the vaccine have not been established in pregnant women or in individuals with a history of Guillain-Barre Syndrome.

The most common adverse reactions associated with F. Valence are injection site pain, swelling, and erythema.

G. Heterotypic Vaccine:

A vaccine consisting of two or more antigenically different components.

I. Immunogen: A molecule that can elicit an immune response.

J. Immunologic Memory: The ability of the immune system to remember a previous encounter with an antigen and mount a more rapid and effective response on subsequent exposure.

K. Immunosuppression: The impairment of the immune system.

L. adjuvant: A substance that enhances the effectiveness of a vaccine by promoting a more robust immune response.

H. mRNA Vaccine:

The mRNA vaccine is a type of vaccine that uses pieces of genetic code from a virus or disease to help the body build immunity to that virus or disease. The body recognizes the mRNA as if it was the virus or disease itself, and begins to produce antibodies to fight it.

Vaccination

A vaccine is a preparation that helps the body develop immunity to an infection. Immunization with a vaccine helps protect people from diseases caused by microorganisms, such as viruses or bacteria, by stimulating the body to produce immunity to them. Vaccination is a proven way to prevent infections and save lives.

Uses of Vaccination

There are many uses of vaccination. Some of the most important ones are listed below.

Vaccination helps prevent serious diseases.

It helps protect people who cannot be vaccinated, such as those who are too young or have a weak immune system.

It helps prevent the spread of disease.

It can help keep people healthy and may help reduce health care costs.

What is an Immunization?

Immunization is the process by which a person is made immune or resistant to an infectious disease. Immunization can occur naturally, as with some childhood diseases like chickenpox, or it can be artificially induced, as with a vaccine. Immunization is one of the most effective public health tools available for preventing disease.

Process of Immunization

Immunization is a process by which a person is exposed to a weakened or dead form of a virus, bacteria, or other organism. This exposure allows the person’s immune system to develop immunity to that organism. Immunity is a natural defense against infection or disease. Immunization can help protect people from getting sick, and can also help to protect people who are unable to be immunized, such as those who are too young or too sick. Immunization is one of the most effective ways to prevent disease.

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