Immunisation

Immunisation with a vaccine is the process of protecting an individual against infection using passive or active immunity.

The Role of Vaccination in Improving Health

Vaccination as a public health strategy has revolutionised global health by saving and improving the quality of life for billions of people.

Vaccination programmes have been highly effective in the control of many infectious diseases that were once common in the UK such as polio, tetanus, and Haemophilus influenzae type b (Hib) and diphtheria.

Worldwide, the most successful vaccination campaign to date was against Smallpox. Once a major disease that caused severe disfigurement and death, Smallpox has now been totally eradicated. 

Without continuing high levels of vaccine uptake, epidemics of many “preventable” childhood illnesses could return, as has occurred with mumps and measles. In the UK and Europe there are on-going outbreaks of mumps and measles affecting unvaccinated young people and children due to the low uptake of the MMR vaccine arising from a misplaced fear of vaccine associated autism.

Vaccines can directly protect both the people who receive them and those people with whom they come into contact. Therefore there is the requirement for healthcare workers to receive occupational vaccines against HBV and MMR.  

Vaccination can also be used to prevent cancers (oral cancer, penile cancer and cervical cancer) caused by the Human Papilloma Virus (HPV) serotypes 16 and 18 and liver cancer caused by Hepatitis B Virus (HBV).

Types of Vaccines: Passive Immunity

Immunoglobulins are specific concentrated antibody preparations that provide immediate but short-term protection against disease for those at high risk of severe disease or complications, such as immunocompromised patients or pregnant women.

Non-immune healthcare workers, such as individuals who failed to develop immunity after completing a course of HBV vaccine, may be offered HBV globulin (HBIG) after a high risk needle stick injury involving an infectious Hepatitis B patient.

Types of Vaccines: Active Immunity

Protection is achieved through stimulating the individual's immune system either by exposure to the infection naturally or by vaccination, and is usually long lasting. Active immunity generally involves cellular responses, serum antibodies or a combination acting against one or more antigens on the infecting organism.

Both vaccines and the immune response to natural infection produce their protective effect by inducing active immunity and providing immunological memory. Immunological memory enables the immune system to recognise and respond rapidly to exposure to the same infection at a later date, thereby preventing the infection or making the symptoms of the disease less severe.

Evidence of immunity shortly after vaccination or recent natural infection is determined by detecting antibodies to the infective organisms in blood.

With time the concentration of protective antibodies dwindles, but even in the absence of detectable antibodies immunological memory may still be present. For some infections, booster doses of vaccines are sometimes required in order to reinforce and maintain immunological memory.

There are Two Main Types of Active Vaccines

Inactive Vaccines
For example, tetanus toxoid, inactivated microorganism such as hepatitis A vaccine, or subunit vaccines such as acellular pertussis vaccine that contain immunogenic proteins or parts of the virus know to stimulate a protective immune response

Modified, Attenuated Live Organism
For example, oral polio vaccine or MMR. Live vaccines contain safe, modified versions of the virus. They do not cause the actual illness but vaccine recipients may experience very mild symptoms such as local soreness or swelling at the injection site or low grade fever. Patients with severely compromised immune systems due to cancers or AIDS will need to seek expert advice as some live vaccination may be unsuitable for them.

Dental Team Vaccine Department of Health Guidelines

The Department of Health guidelines recommend that clinical members of the dental team should be up to date with the following vaccines: 

  • Hepatitis B (HBV) vaccine (antibody titres for hepatitis B should be checked one to four months after the completion of a primary course of vaccine).
  • Measles Mumps and Rubella (MMR) vaccine (unless documentation is provided of having received two doses of MMR or having had positive antibody tests for measles and rubella).
  • Chickenpox vaccine if non-immune (protects against chicken pox and shingles).
  • BGC vaccine (protects against TB - immunity tested with Mantoux test).
  • Tetanus, polio, diphtheria (routine vaccinations).
  • Seasonal Flu (annual vaccine)

Non clinical staff such as receptionists and cleaners should be up to date with the following vaccines: 

  • Tetanus, diphtheria, polio, MMR (routine vaccinations).
  • Hepatitis B (a requirement for staff who come into contact with body fluids and blood during their work or there is a risk from sharps injury or splashes such as handling clinical waste).