Vaccination is considered as one of the most effective health care intervention that has saved lives of millions of children.
What are infectious disease?
Infectious disease are illnesses caused by microorganisms or germs. Germs are very small in size and cannot be seen without a microscope. They could be of many different types that include: bacteria, viruses, fungi and protozoa. They can make us sick when they enter in our body.
Germs can be transmitted through air droplets from infected person to healthy person such as Tuberculosis, Chickenpox; – by consuming contaminated food & water such as Typhoid fever, Hepatitis A; – through blood transfusion or other body fluids such as Hepatitis B, Hepatitis C; – and due to insect bite example Malaria, Dengue (due to mosquito bite) or animal bite for e.g. Rabies (due to dog or cat bite).
Vaccines protect us from infectious disease. Infants and children are most sensitive to get infections, therefore most vaccines are given during the 1st and 2nd years of life to prevent infections in children.
What are Vaccines?
Vaccines are type of medicines that are used to prevent infectious diseases.
In simple words, vaccines contain the same germs that cause infections. However, the germs used in vaccines are either killed or weakened to make them unable to cause disease. Such as Polio vaccine contains the weakened polio virus, similarly measles vaccine contains the weakened measles virus. Many newer vaccines only contain the small of piece of the germ, such as Hepatitis B vaccine contain the protein that is present on the surface of the Hep B virus.
As a result of vaccination, the immune system produces antibodies against the type of the vaccine – example Measles vaccine will trigger production of antibodies that protect from measles infection and polio vaccine would trigger antibodies against polio infection. These specific antibodies protect us from getting the infection when exposed to these specific germs in future.
Can vaccine cause side effects or adverse reaction?
Like all other medicines, vaccines may also cause some side effects, however they are very rare. It is important to stay in clinic or hospital for 30 minutes after the administration of the vaccine to ensure availability of medical support in case of a side effect or allergic reaction. Vaccine side effects are usually non-serious and short-lived.
Following diseases are effectively prevented from vaccination
TB is a bacterial disease caused by a bacterium called Mycobacterium tuberculosis.
TB bacterium most commonly causes infection in lungs, however it can also cause infection in brain, bones, kidneys and other parts of the body. TB is very contagious disease, it spreads through droplets from infected person to healthy individuals. Symptoms of lung TB may include persistent cough with blood, fatigue, chest pain and weight loss.
Some types of TB infections can be prevented with BCG vaccine (see Vaccination Schedule)
Hepatitis B is a viral infection that causes inflammation in the liver.
Hepatitis B infection can be of two types
Acute (short-term) – it causes the inflammation of liver tissues for a short period of time (few weeks to a couple of months). The patient’s body is able to fight the disease and the patient recovers complete healthy state with no long-term complications. Acute infection mostly occurs when the virus enters the body in adult or older age.
Chronic (Long-term) – In this type, the patient’s body is not able to fully fight the disease. In this type, usually the patient gets the virus at very early stage of life (less than 5 years old). About 90% of infants who get the Hep B virus from the Hep B carrier mothers would develop chronic Hep B infection. Most patients recover health after suffering with jaundice and stay healthy all their life, but the virus remains in the body for the whole life. However, about 5 – 10% patients can develop complications like serious damage to liver leading to cirrhosis and cancer.
Hepatitis B can be effectively prevented with vaccination (see Vaccination Schedule)
Pneumococcal diseases (Pneumonia)
Pneumonia is an infectious disease that affects lungs in people of all age. Mostly commonly, the disease is caused by a few types of bacteria and viruses. Pneumonia is mostly commonly caused by the below mentioned microorganisms.
- Streptococcus pneumoniae
- Haemophilus Influenzae type B (HiB)
- Bordetella Pertussis
- Measles Virus
- Varicella Zoster virus (Chickenpox)
- Influenza (Flu) virus
Luckily, very effective and safe vaccines are available that can protect the children and adults from pneumonia caused by above mentioned microorganisms (see Vaccination Schedule)
Poliomyelitis virus (Polio)
Polio is an infectious caused by Polio virus. Polio virus can cause serious life-threatening disease in children leading to death or life-long disability. The virus enters the body through consuming contaminated water or food.
Through the use of Polio vaccine, the disease is successfully eradicated from all over the world except Pakistan, Afghanistan and Nigeria.
Vaccinating children is the best way to avoid Polio infection. Parents should ensure that their children must receive all required doses of Polio vaccine. See Vaccination Schedule
Meningitis is a disease in which the membrane surrounding the brain and spinal cord (called meninges) gets inflamed or swollen. It most commonly develops due to viral or bacterial infection.
Generally bacterial meningitis is more severe than viral meningitis. It is very important to know the cause of meningitis, however it is difficult to identify the cause at early stage. Urgent medical care is required to control the infection and prevent death or permanent disability, especially in children and elderly.
Major causes of meningitis are listed below
• Streptococcus pneumoniae
• Haemophilus Influenzae type B (HiB)
• Neisseria meningitides
• Group B Streptococci (mostly affects infants)
• Listeria monocytogens
• Measles virus
• Mumps virus
• Varicella Zoster virus (Chickenpox)
• Influenza (Flu) virus
• Naegleria fowleri
Many types of meningitis can be prevented from vaccination (see Vaccination Schedule)
Diphtheria is a serious infection caused by a bacterium called Corynebacterium diphtheria.
Typically it affects throat and nose; causing sore throat, high fever and may result in severe damage or death if proper treatment is not initiated immediately. Diphtheria can also severely affect the heart, kidneys and nerves.
Diphtheria infection used to be very common worldwide. The number of diphtheria cases have significantly dropped globally due to increase use of diphtheria vaccine. There are still a few thousand diphtheria cases occur every year in Pakistan. Majority of the cases can be easily avoided by increasing diphtheria vaccination coverage.
Diphtheria vaccination must be given to children as part of the childhood vaccination program (see Vaccination Schedule)
Tetanus is caused by a bacterium called Clostridium tetani.
Tetanus is a very serious disease – more than 25% tetanus patient end up in life-long disability or death.
The bacterium is actually present everywhere; mainly in soil, manure and dust – enters the body through a skin cut or open wound.
Adults should be administered tetanus antitoxin if they have open wound or injury.
Tetanus can be prevented from a very effective vaccine (see Vaccination Schedule).
Pertussis or whooping cough is a respiratory disease caused by bacterium Bordetella pertussis.
Pertussis is a very serious infection causing uncontrollable cough and breathing difficultly. The symptoms are severe in infants and children.
Pertussis vaccine protects children from developing whooping cough (see Vaccination Schedule)
Measles is highly infectious disease caused by Measles Virus.
Measles virus can be transmitted through droplets when the infected person coughs or sneezes. The virus enters the body of a healthy person who comes in contact with an infected person.
Measles infection can be serious and life-threatening especially in young children. About 30% of measles infection develops other complications like, pneumonia, ear infection, meningitis and diarrhea.
Measles infection is used to be very common, however due to increase use of MMR vaccine, cases of measles have become very low in developed countries. (See Vaccination Schedule)
Mumps is an infectious disease caused by Mumps virus.
Mumps is very infectious disease, it can quickly transmit through the droplets from the sneeze and cough of infected person to healthy person (who did not have mumps vaccination or mumps infection earlier).
Patient usually experience fever, tiredness and chills with swollen salivary glands (jaws) under the ears (one side or both side)
Mumps can be easily protected from MMR vaccine (see Vaccination Schedule).
Rubella is viral disease caused by Rubella virus. It is also called as German measles
It caused mild sore throat, skin rash and fever. In pregnant women, it can cause miscarriage and birth defects if they are not vaccinated with Rubella vaccine. It is therefore important to get the Rubella vaccine.
Rubella vaccine is included in the MMR shot – (see Vaccination Schedule)
Chickenpox is an infectious disease caused by Varicella-Zoster Virus (VZV).
It is a common childhood infection usually occurs in less than 10 years old children. Almost everyone gets it in the childhood years. People who are not vaccinated with chickenpox vaccine or never had chickenpox infection, can get this infection at any age.
It causes red itchy rash, which later turn into watery pus-filled blisters and eventually become dried crust and fall off. Possible complications occur when blisters get infected with bacteria.
Chickenpox vaccination is safe and effective way of preventing the infection (see Vaccination Schedule)