Immunizations in Children
According to World Health Organization (WHO), “Immunization is the process whereby a person is made immune or resistant to an infectious disease, typically by the administration of a vaccine” (World Health Organization). This definition of WHO can be further elaborated by saying that the concept of immunization works by stimulation of the immune system. The immune system performs the function of protecting the body against disease causing agents.
In its healthy condition, the body’s immune system has the ability to recognize any invading microbe. The leucocytes identify the microbes and produce antibodies against them. These antibodies are capable of fighting against the antigens which invade the body. In the process of immunization, this same principle is used. The body is made to develop antibodies against the antigens which are introduced in the dead or weakened form in a very minute dose. On encounter, the body considers these artificially introduced agents as invaders and produce antibodies against them. The antibodies produced here actually does not have much of a role to play in preventing this particular attack, but it can prevent the body from getting affected in the subsequent attacks.
The minuteness of the introduced antigens and their low virility help in eradicating the effects of the antigens at a fast pace and hence the body becomes free of the disease. however, the antibodies hence produced are stored in the body and these cells develop a type of memory against the antigens. On subsequent invasion by the same microbes, these antibodies will be able to recognize the antigens and will thus attack them and will help in setting the body free from the disease causing antigen (MedicineNet).
History of Immunization
Contrary to the conventional beliefs, the concept of immunization did not come forth with the discovery of Edward Jenner, rather it was there even hundreds of years prior to his discovery. The concept of immunization is as old as the concept of infectious disease among the human beings. There are evidences which support the fact that the Chinese used the idea of smallpox inoculation even in the 1000 BCE. The use of smallpox inoculation was prevalent in Turkey and Africa before it moved to the American and European countries. Edward Jenner contributed in this field through the huge success of using cowpox inoculation for treating smallpox in the year 1796. His invention further underwent improvements for the next 200 years which eventually led to the eradication of smallpox completely. The next major step was taken by Louis Pasteur through his discovery of the rabies vaccine in the year 1885. Along with this, further development in the field of science and technology and bacteriology, helped in further continuation in the progress towards the betterment of immunization. Through the year 1930, more vaccines for diphtheria, cholera, plague etc. were brought about which further marked the progress.
The mid 20th century proved to be a milestone in the field of research and development about vaccines. The success in growing viruses in laboratory made a breakthrough and added up to the pace of discoveries in the sphere of immunization. These developments led to the development of polio vaccine and thus helped in eradicating the disease in a span of few years from many parts of the world. Research work continued and vaccines for diseases like mumps, rubella etc. cropped up, hence helping in reducing the burden of these diseases from various parts of the globe. DNA recombinant technology along with vaccine research has added strength to the field of immunization (The College of Physicians of Philadelphia).
Types of Immunization
There are basically two types of vaccines:
Live attenuated vaccine
Inactivated vaccine
According to a general convention, the more similar the vaccine is to a natural disease, better is the immune response.
Live attenuated vaccines are prepared by modifying the disease producing microbe within a laboratory setting. The modified organism thus has the ability to grow and provide immunity to the immunized person. Although the organism is a disease causing microbe, but modification makes it harmless and hence useful for treating diseases. Mostly, the live attenuated organisms used for making vaccines are viruses and bacteria. On the other hand, inactivated vaccines are developed from whole viruses or bacteria or some parts or fractions of these. There are sub groups of the inactivated vaccines. The vaccines obtained from fractions of the microorganisms are polysaccharide based or protein based. The vaccines having protein as bases include certain toxoids or some subvirion product. The vaccines having polysaccharides as bases are made of pure cellular wall polysaccharide obtained from bacteria. Then comes the conjugate vaccine which is composed of both polysaccharides and proteins. This association increases the strength of polysaccharides.
As discussed earlier, live attenuated vaccines are modified forms of disease producing organisms. The modification is brought about by repeated culturing of the microbe in the laboratory. For better understanding, we can take the example of measles virus. The virus was first isolated from a child suffering with measles in the year 1954. It took ten years of laborious work to bring the modification in the disease causing microbe and make it suitable for the purpose of vaccination. The modified organism is then introduced into the body and allowed to replicate in order to stimulate an adequate immune response. In very rare cases these live attenuated vaccines may cause a mild disease which resolves quickly. Some examples of currently available live attenuated vaccines are oral polio vaccines, measles, rubella, mumps, yellow fever, oral typhoid vaccine, BCG and influenza.
Inactivated vaccines on the other hand are produced by making the organism grow in a culture medium and then making it inactive by exposing it to heat or with chemicals. For making fractional vaccines, the organism is made to undergo purification for obtaining the required parts of the organism. The organisms in this form of vaccine are not alive and do not have the ability to replicate. Due to their inactive state, the organisms cannot produce disease even in an immunodeficient person. The inactive vaccines must be administered in multiple doses for efficient functioning. Some examples of currently available vaccines in the inactive forms are Hepatitis B, cholera, plague and so on.
An important class of inactivated vaccines are the polysaccharide vaccines. These vaccines are prepared from long chain of sugars which is obtained from the capsule of certain bacteria. Most of these vaccines are able to stimulate an immune response directly from B cells. Infants usually do not respond to this particular type of vaccine, the reason could be the immaturity of their immune system. In order to combat this issue a new class of vaccines called as conjugate vaccines were devised. In 1980s invention of conjugate vaccine came up as a solution to this problem. The conjugate vaccines work by changing the immune response from T- cell independent to T- cell dependent cellular response. This improves the immune response among the children and infants too. The first ever conjugate vaccine was developed for Hemophilus influenza B. Nowadays the vaccines for pneumococcal and meningococcal diseases are also present. Recombinant vaccines constitute an entirely different class of vaccines. Genetic engineering has helped in devising vaccine antigens. Currently available genetically modified vaccines are Typhoid vaccines, influenza vaccines, HPV vaccines and Hepatitis B vaccine (Immunization Advisory Centre).
Immunization Schedule for Children
At Birth: Hepatitis B vaccine; to be given right after birth. If a child could not receive the vaccine at birth due to any reason, then the vaccine may be given at any stage later in life.
1st- 2nd month: 2nd dose of Hepatitis B vaccine must be administered after a month or two following the 1st dose.
2nd month: DTP vaccine for Diphtheria, Tetanus and Pertussis.
Hemophilus influenza type B vaccine
Inactivated Polio virus vaccine or IPV.
Pneumococcal Conjugate Vaccine
Rotavirus vaccine
4th month: DTP vaccine for Diphtheria, Tetanus and Pertussis.
Hemophilus influenza type B vaccine
Inactivated Polio virus vaccine or IPV.
Pneumococcal Conjugate Vaccine
Rotavirus vaccine
6th month: DTP vaccine for Diphtheria, Tetanus and Pertussis.
Hemophilus influenza type B vaccine
Pneumococcal Conjugate Vaccine
Rotavirus vaccine: The need for third dose depends on the brand of rotavirus
vaccine used for previous immunization.
6th month and Yearly: Influenza vaccine should be given once in a year to every child who is
at least 6 months old. A yearly dose of the vaccine can prevent the child from any serious complication.
6th to 18th months: Hemophilus influenza type B vaccine
Inactivated Polio virus vaccine or IPV.
12th to 18th months: Hemophilus influenza type B vaccine
Pneumococcal Conjugate Vaccine
Chickenpox vaccine
Mumps, Measles and Rubella vaccine
12th to 23rd month: Hepatitis A vaccine, given at an interval of six months in two doses
15th to 18th month: Diphtheria, Tetanus and Pertussis vaccine
4th to 6th year: Chickenpox
Mumps, Measles and Rubella
Inactivated Polio Vaccine
Diphtheria, Tetanus and Pertussis vaccine
11th- 12th year: Human Papilloma Virus vaccine
Diphtheria, Pertussis, Tetanus Vaccine
Meningococcal Vaccine
18th year: Meningococcal Vaccine
Vaccines given in Special Circumstances
Hepatitis A vaccine is recommended for children who are 2 years old or above that age group. This vaccine must be given to those who are at high risk of developing Hepatitis A, for example the children and adults who live in, shifted to or have adopted children from regions of the world where the prevalence of Hepatitis A is very high. It is also recommended for people having clotting disorders, chronic hepatic disease, or any person who desires to acquire immunity against this disease. It should also be taken by persons who work in childcare centers as they are also highly susceptible to developing Hepatitis A.
Influenza vaccine should be given to children who are at higher risk of developing frequent flu. These children are usually below the age of five years or are the sufferers of chronic health conditions like asthma.
Meningococcal vaccines: This vaccine is usually given to children who are susceptible to meningococcal viral infection and prone to develop meningitis. The vaccine can be administered to children as young as even 2 months of age.
Pneumococcal vaccines: This vaccine is usually given to children who are susceptible to recurrent infections like HIV affected, patients of splenic disorders etc. (Joseph).
Vaccination Side Effects
Almost all the vaccines have the potential to cause some mild to moderate side effects. However, it is not necessary that every vaccinated individual will develop such side effects. Some of the commonly observed mild side effects are as follows:
Low grade fever
Site reactions like swelling, pain and erythema
Fatigue
Shivering
Musculoskeletal pain
Headache
Rarely observed side effects of vaccination:
Anaphylactic reaction: This is a rare occurrence which is characterized by immediate allergic reaction to the administered vaccine. The condition can be life threatening. The condition is extremely rare, hardly one case can be seen among a million people. the condition can be treated effectively if timely action is taken
In case a child develops any of the usually observed side effects after being vaccinated then the parents can wait for a day or two for the symptoms to subside by themselves. In case the child develops high fever, the parents should try to keep the baby cool. A dose of anti pyretic drug can also be given in such cases.
Every pack of vaccine comes with a leaflet which enumerates all the potential side effects of a vaccine. Such patient information leaflets can also be found and read from the internet prior to getting the vaccines administered. In case the symptoms refuse to subside or show any sign of aggravation, then the parents must consult the physician at the earliest (Nhs.uk).
However, recent development in the field of science and technology has brought about the fact that certain vaccines do have some side effects. This recognition came into effect after many years of research. But the number of cases showing such side effects is not sufficient enough to outweigh the benefits of vaccination (Mercola).
Myths and Facts about Vaccination
There’s no need of taking vaccines for diseases of rare occurrence
Fact: The diseases that have become rare are a result of repeated vaccinations provided to the children. The places where the vaccines are not administered regularly, the incidences of the rare diseases have shown to increase the rate of incidence.
Use of thimerosal as a preservative agent makes the vaccines unsafe for use
Fact: The recommended dose of thimerosal for using as a preservative is completely safe. It does not produce any serious complication. Still, as the concern is seen to be rising among the parents, the US government has stopped the use of thimerosal in almost all the vaccines except some of the flu vaccines.
Vaccines may cause autism
Fact: As the symptoms of autism appear almost simultaneously along with the MMR vaccine, it made people belief that there is a link between the two. But repeated researches have proved that there is no link between the MMR vaccine and autism.
Bioterrorism and Immunization
The fear of being attacked by biological weapons among the people has led to certain questions in their mind. One of the most important questions is that if people should get immunized against diseases like anthrax in order to prevent themselves from a possible biological attack. But according to the Centers for Disease Control and Prevention (CDC), the risk for such attacks and diseases is very low among general population and hence people do not need any vaccination. However, CDC does recommend laboratory workers and military personnel to get vaccinated against such diseases due to their high susceptibility to such diseases (WebMD).
Some Interesting Facts on Immunization
Almost two to three millions of children are saved from death with the help of immunization across the globe.
In the year 2010, almost one hundred and nine million children were vaccinated against some deadly diseases like diphtheria, pertussis and tetanus.
More than one million of children die every year of rotavirus infection and pneumococcal diseases due to lack of vaccination
The diseases preventable by vaccination can produce better results in terms of prevention if the public- partnership can rise in different parts of the world.
There has been significant rise in the supply of influenza vaccines with the help of WHO.
Measles mortality rate has dropped by 74% with the help of highly efficient vaccine campaigns
The incidence of polio has reduced to a whopping 99%.
The annual neonatal rate of death has reduced significantly
Immunization programs also help the healthcare professionals to teach the parents about other methods by which they can bring about a general improvement in the health of their children. It is the preferred time for administering vitamin A doses and for providing insecticide nets and other useful life saving materials (World Health Organization).
The concept of immunization thus has a great role to play in our lives. The administration of vaccine although relates mostly to the younger age group has a high relevance throughout the lives of the people. The development of vaccination or the concept of immunization has proved to be a boon for the world. The death rates have lowered significantly following the invention. Latest technological discoveries are adding up to the concept and helping in devising better techniques and introduction of better health care for the general people. There have been numerous controversies surrounding the idea of vaccination since ages and is still continuing, but all these controversies have failed to cause any detrimental effect on the benefit these vaccines provide us with. Every part of the world, including the developing countries have benefitted from the concept of vaccination. The numbers of deaths have dropped significantly since then. The efforts of WHO have been commendable in this regard. It has left no stone unturned to make the vaccines reach every remote corner of the world, especially among the developing countries where people are less educated and ignorant towards their health. It is highly important to teach every parent the importance of these vaccines for the safety of their children. Awareness among parents can save the lives of the children. The myths and wrong beliefs among the people need to be addressed properly so that they develop faith in these vaccines and no child remains unvaccinated. The medical fraternity should work further for the improvement in the field of vaccinations so that more diseases can be covered under vaccination in the future.
Works Cited
"Immunization". MedicineNet. N.p., 2016. Web. 12 Apr. 2016.
"Immunization". World Health Organization. N.p., 2016. Web. 8 Apr. 2016.
"Immunizations And Vaccines". WebMD. N.p., 2016. Web. 14 Apr. 2016.
Joseph, Elana Pearl Ben. "Immunization Schedule". Kidshealth.org. N.p., 2015. Web. 14 Apr. 2016.
Mercola, Dr. "U.S. Government Says Vaccines Are Dangerous". Mercola.com. N.p., 2011. Web. 14 Apr. 2016.
"Timelines — History Of Vaccines". The College of Physicians of Philadelphia. N.p., 2016. Web. 13 Apr. 2016.
"Types Of Vaccines | Immunisation Advisory Centre". Immunization Advisory Centre. N.p., 2011. Web. 14 Apr. 2016.
"What To Do About Vaccine Side Effects - Vaccinations - NHS Choices". Nhs.uk. N.p., 2016. Web. 14 Apr. 2016.
"WHO | 10 Facts On Immunization". World Health Organization. N.p., 2016. Web. 14 Apr. 2016.
