Vaccinations

Vaccinations

Vaccination involves administering antigenic material (a vaccine) to trigger an individual's immune system to develop adaptive immunity against a disease. Vaccines can prevent or lessen the impact of infections caused by various pathogens. The effectiveness of vaccination has been extensively researched and confirmed, with examples including the influenza vaccine, the HPV vaccine, and the chickenpox vaccine, among others.

Generally, vaccination is recognized as the most effective method for preventing infectious diseases. The active component of a vaccine may consist of intact but inactivated (non-infectious) or attenuated (with reduced infectivity) forms of the disease-causing pathogens, or purified components of the pathogen that have been found to be highly immunogenic (such as the outer coat proteins of a virus).

Toxoids are developed for immunization against toxin-based diseases, involving modifying toxins like tetanospasmin toxin of tetanus to eliminate their toxic effects while retaining their immunogenic properties.

Since their inception, vaccination efforts have faced controversy on scientific, ethical, political, medical safety, religious, and other grounds. Despite initial challenges, early successes and mandates led to widespread acceptance, and mass vaccination campaigns have been instrumental in significantly reducing the incidence of many diseases in various geographic regions.

Types of Vaccines

All vaccines function by introducing a foreign antigen to the immune system to provoke an immune response, but there are several methods to achieve this. The four primary types currently in clinical use are as follows:

1. Inactivated vaccines: These consist of viruses or bacteria grown in culture and then killed using methods like heat or formaldehyde.

2. Attenuated vaccines: Live viruses or bacteria with very low virulence are administered.

3. Virus-like particle vaccines: These include viral proteins derived from the structural proteins of a virus.

4. Subunit vaccines: They present an antigen to the immune system without introducing viral particles, whole or otherwise.

Vaccinations in Malaysia

Mandatory Vaccinations

- BCG: Administered at birth to prevent tuberculosis.
- Hepatitis B: Given at birth, 1 month, and 5 months to prevent Hepatitis B.
- Triple (Diphtheria, Tetanus, Pertussis) and Polio: Administered in 3 doses with booster shots at 18 months-2 years and 5-7 years to prevent diphtheria, tetanus, pertussis, and polio.
- Haemophilus Influenzae B: Given in 3 doses with a booster at 1½ years to prevent against Haemophilus Influenzae B.
- Measles, Mumps, and Rubella: Administered after one year old in two doses to prevent against measles, mumps, and rubella.

Recommended Vaccinations

- Influenza: Given annually to protect against influenza.
- Chickenpox: One jab for life to protect against chickenpox.
- Pneumococcal: Given as three doses in the first six months with a booster after a year to prevent pneumonia, meningitis, and infections.
- Rotavirus: Given in three doses, a month apart, alongside the triple shot to prevent rotavirus infection.
- Hepatitis A: Given above the age of two in two doses, six months to a year apart, to protect for life against Hepatitis A.