Immunization

Introduction Immunization is the process whereby a person is made immune or resistant to an infectious disease, typically by the administration of a vaccine. Vaccines stimulate the body’s own immune system to protect the person against subsequent infection or disease (Vaccines are weapons to prevent diseases) Immunization is a way to protect child from getting a number of illnesses. Many of these illnesses are easily spread from child to child and can cause serious health problems.

Child immunization and Vaccination of pregnant women Child immunization is immunization of children with vaccines to protect them against some diseases. Vaccination of pregnant women with TT (Tetanus) vaccine: This protects mothers against Tetanus and protects new born babies from neonatal Tetanus.

Types of Immunity-Passive Immunity Passive immunity is provided when a person is given antibodies to a disease rather than producing them through his or her own immune system. A newborn baby acquires passive immunity from its mother through the placenta.

Types of Immunity-Active Immunity Active immunity results when exposure to a disease organism triggers the immune system to produce antibodies to that disease. Exposure to the disease organism can occur through infection with the actual disease or through vaccine.

Passive immunity and Active immunity A person is given antibodies to a disease Exposure to a disease organism triggers the immune system to produce antibodies to that disease. Protection is immediate Takes time (usually several weeks) to develop Lasts only for a few weeks or months Long-lasting

Types of vaccine: 1. Live vaccine: vaccine containing live attenuated microorganisms It could be viruses: e.g. measles, mumps, oral poliomyelitis (sabin), and rubella vaccine. Or live attenuated strains of bacteria, e.g. BCG (bacilli calmette-Guerin). 2. Killed vaccine: vaccine not containing live microorganisms. They contain killed microorganisms, Inactivated (killed) virus: e.g. hepatitis A,B, poliomyelitis (Salk) vaccines. Inactivated (killed) bacteria: pertussis (whooping cough), 3. Vaccine containing the toxins that the bacteria produce, after changing them into harmless toxoid, such Tetanus toxoid TT and diphtheria toxids

Cold Chain System Vaccines are delicate biological substances that can become less effective or destroyed if they are frozen, allowed to get too hot, and exposed to direct sunlight or fluorescent light. Cold Chain: a system of transporting and storing vaccines within the safe temperature range of +2 °C to +8 °C from the place of manufacture to the point of administration. This temperature range is recommended because outside this range vaccines may (very quickly) lose their potency. Freezing: a situation where vaccines experience temperatures at, or below, 0 C. Freeze Monitor: a device that indicates exposure to < 0 °C for periods greater than 30 minutes. Time Temperature (heat monitor): a device that indicates exposure to excessive temperatures.

Cold-chain monitors Cold-chain monitors (CCM) include time temperature (heat monitors) and freeze monitors. The CCM should accompany all vaccines during any long distance vaccine transport. The CCM should not be removed from the (cold box) container until all vaccines have been removed for either use or storage.

What damages vaccines? All vaccines lose their potency after a certain time you know that time from the expiry date printed on the vaccine. Heat & sunlight can damage vaccines, especially the live attenuated ones (measles & BCG). Freezing damage the killed vaccines and toxoids (Pertussis & Hepatitis B) Disinfectants or antiseptics can damage vaccines.

Contraindication to child immunization: There are almost no contraindications to vaccination Children with a mild illness should be immunized as usual Children with malnutrition can develop good immunity, so immunize them as usual because they are more likely than other children to die from some diseases, especially measles

Contraindications are: Very severely ill children who need to be hospitalized, or children who have very high fever, should be delay vaccination. If a child has had severe reaction from DPT injection (convulsions or shock) (DPT is a combined vaccine for Diphtheria, Pertussis and Tetanus) do not give that child any more doses of DPT. Give him DT vaccine. BCG is the only vaccine which not be administered to children with clinically apparent AIDS or Immune deficiency diseases, premature babies, malnutrition, and infection skin disease.

Preparation for immunization session An immunization session should be in enclosed site. Give mothers the information they need on vaccination. Check the expiry date of the vaccine before use. Register carefully the doses that given to the child in the health unit register and on the immunization card. Put the vaccines into a cup of ice. Throw away any open vials of vaccine that remain after the immunization session. Use a disposable syringe for each child and destroy it after use so it cannot be used again. Use oldest vaccine that has been in your refrigerator for the longest time first.

Adverse reaction of some vaccines: Measles & MMR( measles, mumps, and rubella): child may have: Fever. Transient rash. Arthralgia Pertussis: child may have:(several to 72hrs): Redness, pain, swelling at injection site. Fever (slight to moderate). Anorexia, drowsiness. Poliomyelitis vaccines: Breast milk may contain specific antibodies, which interfere with oral polio. So avoid breast feed baby 1/2-hr before and after the vaccine. Baby may spit or vomit the vaccine

Vaccine carrier Close the lid tightly Clean and dry after every use Put vaccine vials and ampoules in a polythene bag and close it Keep the carrier away from direct sunlight The carriers with four ice packs can keep the vaccine cold for 2 days Do not sit or place anything heavy on a vaccine carrier

Vaccine carrier A carrier for small quantities of vaccines (16-20 vials) The vials of DPT (DPT is a combined vaccine for Diphtheria, Pertussis and Tetanus), and TT (Tetanus) vaccines should not be in direct contact with the frozen packs The ice packs for lining the sides of the carrier should be fully frozen Place fully frozen ice packs in the carrier and wait for few minutes for temperature to fall to less than 8 degree Celsius

Vaccine refrigerators The correct temperature to keep vaccine is between +2c° and + 8 c° Follow storage guideline Do not store food or drink in vaccine refrigerators. Store vaccines only on the middle and upper shelves in the refrigerator Allow air to circulate within the refrigerator, by not crowding or overfilling the refrigerator with the vaccines. A gap of at least 4 cm from all walls and between large packages of vaccine vials is recommended Freezing does not damage live attenuated vaccines "BCG", oral polio and measles vaccines. Freezing damage the killed vaccines and toxoids (DPT, DT, TT)