Vaccination

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Contents

Introduction

Until GANFYD has more content, you might like to try NHS Immunisation Information. Detailed information - the Immunisation "Green Book", including updated chapters, is available at via the Department of Health's web site. A new paper edition has just been published. It is available from HMSO or (for UK health professionals), your local health authority.

If you're interested in joining a discussion list for people professionally involved in vaccination (whether as a healthcare professional advising patients, giving the jabs, or making vaccine policy you might want to join the vaccimmuk Yahoo! group.

Background

See also Artificial induction of immunity. When considering vaccination and immunisation, we are generally referring to stimulating the body's immune system to provide protection should it encounter a particular pathogen.

In modern parlance "immunity" is the state of protection from infection that you hope to provide; and "vaccination" describes the process intended to provide this immunity.

In addition to preventing infections, vaccination may also be used to treat infections (by stimulating a stronger immune response than natural infection); and also to prevent or treat other conditions such as high blood pressure.[1][2]

Vaccination

Vaccination succeeded inoculation - or variolation - and was rapidly recognised as being much safer, and sufficiently effective.

The term "vaccination" is derived from the Latin for "cow" - because the first vaccine was the cowpox virus administered in 1796 by Edward Jenner (1749-1823), used to prevent smallpox. In 1980, as a result of huge and sustained public health efforts and enabled by Jenner's work, the World Health Assembly officially declared "the world and its peoples" free from endemic smallpox. Pasteur adopted the word for subsequent immunisations including Rabies which was a killed virus preparation.

The word "vaccination" is nowadays used to mean the process of giving a product containing antigens, with the intention that the body will generate antibodies to these antigens, thus giving the person immunity to pathogenic organisms expressing these antigens (active immunity).

Info bulb.pngThe vaccine virus (Vaccinia) was later found to have changed considerably from cowpox. A similar discovery was narrowly reported at the end of the twentieth century in the BCG culture. The former clearly worked very well, the latter possibly less so.

Attacks on vaccination began in 1798, and were based on a variety of spurious ideas including god's will, but could later have included some useful alarms on cross-infection. Sadly, the strident idiocy with which they were made and which persists in many cases in present day arguments, made it difficult to discern any sense in them. In modern times there is an overlap between anti-vaccine activity and denialists on smoking and global warming and evolution, a general attack on science and rationality for the most part for immediate profit.

Determining Immunity

Before some expensive, rarely required or relatively hazardous immunisation procedures are conducted, and after some courses of immunisation whose effectiveness is either variable or crucial, an attempt may be made to determine whether the individual is immune to the disease in question. A biological assay by exposing the individual to the wild virulent disease seems both difficult and harsh and since diseases are not perfectly successful in infecting individuals on one exposure also lacking in sensitivity. There are limits to the reliability of such tests, which tend to be proxy rather direct tests of the immune function that gives protection from the disease. See main article determining immunity

Immunisation

Immunisation is any process that provides an individual with immunity to a pathogen. This may be achieved through natural infection or through vaccination. It can also be achieved by giving the individual immunoglobulin containing antibodies to the pathogen.

Active immunisation may give individuals "immune memory", meaning that their immune system is "primed", and able rapidly to generate antibodies if the same antigens are encountered in the future; or it may generate antibodies without generating immune memory. Many simple polysaccharide vaccines do not generate immune memory (and may only generate humoral immunity. In contrast, most live organism vaccines and conjugate vaccines generally do generate immune memory, and sometimes also cell-mediated immunity.

There is a wealth of information on vaccination and immunisation on Ganfyd - see the Vaccination category for a list of related pages.

Scientific Principles

(See Conjugate vaccines.)

Political Principles

Vaccine policy is formed with advice from the Joint Committee on Vaccination and Immunisation and input from a wide range of organisations.

The Health Protection (Vaccination) Regulations 2009, due to come into force on 1 April 2009, give JCVI recommendations extra force.

Ethical Principles

Vaccination benefits not just the individual who is vaccinated, but also the wider community - at least where vaccination prevents infection and onward transmission of disease, as is the case with most (but not all) vaccines - see Universal vaccination and herd immunity below. There are, therefore, significant ethical dimensions to decisions about vaccine policy;[3] and at some times and places compulsory vaccination is or has been imposed.[4]

Vaccine damage

Anti-vaccinationists make many spurious claims about adverse reactions to vaccination; but vaccination is remarkably safe.[5]

Payments may be made under the Vaccine Damage Payment Scheme - see chapter 10 of the 2006 edition of the Green Book. The payment will rise from £100,000 to £120,000 on 12 July 2007.[6]

Controversy remains as to whether vaccine damage has actually occurred in many of the patients awarded such payments - see, e.g. The vanishing victims by Brian Deer.

Fault and compensation

British law requires demonstrating fault in order to award compensation. Since people in similar condition require similar care or would benefit to similar extents regardless of the cause, there is something to be said for a system of no fault compensation, not least that the legal process in many countries appears to consume around half of any resources available, while providing assistance to around half of those needing it. No-fault compensation for assorted conditions has been implemented in New Zealand, some of the results are troublesome.

See also negligence

National Body Statements

Canadian Pediatric Society statements on immunisation (Incl Andrew Wakefield).

Supply and availability of vaccines in the UK

England

The vaccines used for many of the routine NHS childhood vaccine programmes are provided via a company called Healthcare Logistics.

A monthly newsletter on the availability of vaccines is produced by the NHS Purchasing and Supply Agency. It is available at their website, here, or on request.

Other vaccines must be ordered through general pharmaceutical supplies channels, or via the manufacturers.

Wales

Scotland

Northern Ireland

Monitoring of vaccination uptake

Nationally used for:

  • Evaluating the programmes
  • Monitoring time trends
  • Feedback to public health professionals and policy makers
  • Targeting areas of low coverage
  • Measuring vaccine effectiveness
  • Modelling, planning and policy development

Locally used for:

  • Early ’analysis’ and follow-up of defaulters
  • Comparison between different vaccination providers, e.g. -
  • General practitioners
  • Health visitors
  • Validation of data held locally
  • Local public health reports

UK systems

Cover system for collecting data on childhood vaccination

The main system used for monitoring vaccination uptake in England and Wales is the Cover system for child health vaccination. This system is good, but far from perfect: in most areas vaccinators (mainly GP practices; and there mainly practice nurses) have to send data separately for this system, in addition to sending data to their primary care organisation for payment purposes: two data collection systems are used; and since vaccinators obtain little or no benefit - especially if they do not use it for call and recall purposes - from completing the child health system forms, data is not always adequate. A system that collects data from GP computer systems, without further intervention required by the user, and is "topped up" with data about vaccinations given in other settings, would proved more complete data.

It is also recognised that COVER data only collects data on completed vaccinations given by the ages of 1, 2, and 5 years - so if vaccinations are given late, but still reduce the number of susceptibles in the community and thus the effective reproductive number the COVER statistics may not reflect overestimate the risk of an epidemic.

Systems for collecting data on vaccinations given to teenagers and adults

Some data are collected via KC50 data; but data on vaccinations given outside the childhood programmes (including teenage vaccination) are relatively poor.

Payments for vaccination

The ways that health care providers are paid for vaccinating patients in the UK are complicated. They are part of the means used to implement health policy.

Universal vaccination and herd immunity

UK policy recommends that some vaccines are provided "universally" - i.e. to everybody. Examples include the routine childhood vaccines. In all cases this is because the individual protection the vaccines provide is important; and in some cases there are huge advantages to the population if the number of individuals who are susceptible to a particular condition is so low that a person with the disease is unlikely to spread it to more than another person (herd immunity) In this situation payment/reimbursement is generally designed to incentivise vaccination - and in particular, incentives to vaccinate while the child is most vulnerabe to the disease, should they encounter it.

Targeted vaccination

UK policy recommends that some vaccines are provided to people in "target groups".

People may be in target groups because:

  • They would be more than usually likely to be vulnerable if infected - e.g. the recommendations concerning the vaccination of old people, or people with pre-existing conditions against influenza and pneumococcal disease; or
  • They are more likely to be exposed to a condition, e.g. quarantine workers and rabies; or
  • They are more likely to spread the condition to others who may be more vulnerable, e.g. vaccinating health care workers, carers, and (in North America) children, against influenza.

Travel vaccination

Certain vaccines are recommended for travel purposes. (See Travel health and/or the Green Book for further guidance.)

'fitfortravel'fitfortravel is a public access website provided by the NHS (Scotland) and compiled by a team from Health Protection Scotland.[Health Protection Scotland] It gives travel health information for people travelling abroad from the UK but emphasises that they should talk over individual needs with their own doctor. One may click on a map or select a destination. Travax is a similar more technical site restricted to doctors. Travax - registration required It has the same basic information but goes into medical detail.

Payment for travel vaccines is particularly confusing. Some vaccinations are paid for on the NHS; others have to be paid for by the patient. There is no obvious logic to this.

Guidance on which vaccines can be charged for and which must be given "under the NHS" is available from the BMA website (subscription/membership might be necessary to access this site).

Other vaccines

There are interesting ethical and technical-legal points about vaccinating people who perceive themselves to be at risk from particular conditions, but who are not in the target group for the vaccine, or when a vaccine exists for the conditions, but is not recommended in the UK. In some cases there may be a small potential benefit to the population if the person is vaccinated, but insufficient benefit to justify a policy which would recommended they receive the vaccine (e.g. an adult who has not had chicken pox would only be recommended it if they were a health care worker; somebody who is not - or does not wish to admit to being - in a risk group might wish to have hepatitis B or A vaccine; and if they are vaccinated they are less likely to get expensively ill with the condition, or to pass it on to others...

In some cases a GP might be able to make a case for vaccinating them on clinical grounds, and prescribe the vaccine on the NHS. In some cases this is explicitly forbidden, and the vaccine can only be prescribed privately, in which case restrictions about private practice might apply (specifically preventing GPs from providing certain private services to their registered patients).

Approaches to vaccination payments

See main article: buying immunisation

Which vaccines are available in the UK?

(See also Vaccination in the UK - a summary of when vaccines were introduced.) Vaccines in the routine UK vaccination schedule protect against:

Childhood immunisation

See childhood vaccination schedule for the detailed schedule of routine vaccinations, injecting children for consideration of technique.

(The above are protected against using DTaP/IPV/Hib vaccine in infancy, with DTaP/IPV or dTaP/IPV as a pre-school booster, and a further booster of dT/IPVafter the age of 10 years.)

Info bulb.pngThe combination MMR was the first Mumps vaccine introduced in the UK. In the US it had succeeded an individual Mumps vaccine. That component remains available there, but the company has not sought a licence in the UK.

(The above are protected against using MMR vaccine.)

Targetted vaccines

are available (and provided on the NHS to target groups, or clinically indicated, or privately on request) against other diseases, including:

Which vaccines are available in other countries?

This World Health Organisation web page allows you to look up vaccination schedules in different countries. Or you can get detailed information on specific countries here.

See also

Training for vaccination practitioners

The HPA has developed some minimum standards for vaccination training, and a curriculum. It also runs training events. See this page for more details.

Health Protection Scotland and NHS Education Scotland have developed an online training package - there's more information about this at Health Protection Scotland's training resources web page.

See also:

External links

References

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