What is Diphtheria?
is an infection that targets the respiratory tract of a human. It mainly
affects the nose and throat but has serious impacts on the lungs and heart if
not treated. It is highly contagious and is spread through the air – by someone
coughing or sneezing, or by contact with the carrier, such as their clothing or
their skin. (nhsdirect.wales.nhs.uk/ – 2018)
is caused by a toxin that is released from a bacterium and not the bacterium
Vaccine’s trade names are: Pediacel or Infanrix IPV Hib, Repevax and Revaxis® (Gov.uk. (2018).)
Diphtheria’s type of vaccine:
vaccines use a toxin that is made by the bacteria, in Diphtheria’s case
Corynebacterium ulcerans, they create immunity to the parts of bacteria that
cause a disease instead of the bacteria itself. That means the immune response
is targeted to the toxin instead of the whole germ. (Vaccines.gov, 2018) “Corynebacterium diphtheriae infects the nasopharynx
or skin. Toxigenic strains secrete a potent exotoxin which may cause
diphtheria.” (Murphy, J. et al. (1996).
Route of Administration:
route of administration of the vaccine is intramuscular. The pharmaceutical
form of the vaccine is a suspension and has a shelf life of 3 years and must be
stored in a refrigerator (2ºC to 8ºC). The vaccine is used for active
immunisation and contains other active ingredients in the formulation such as
tetanus and poliomyelitis. (Electronic
Medicines Compendium – 2018).
Combination: There are 4 combinations: DTaP,
Tdap, DT, and Td. Two of these (DTaP and DT) are given to children younger than
seven years of age and two (Tdap and Td) are given to older children and
adults. (Vaccines.gov, 2018).
How is the Toxoid inactivated?
toxin that cause Diphtheria is separated from bacteria and is added with
formaldehyde which counteracts the poison but does not destroy the toxins
ability to stimulate the production of antibodies – causes the toxin to become
a toxoid (Lee, H. and
Choi, J. (2018)). Therefore, this now
made vaccine with the inactive toxin is safe to use for anyone, even babies.
Toxin belongs to the AB toxin groups because of its structure. It contains an
A-fragment and a B-fragment. The B-fragment delivers the A-fragment so that
cell death can occur. The toxin is also
made up of three folding domains, in the A-fragment consists of the catalytic
domain (C), while the B-fragment consists of two folding domains the receptor
domain (R) and the translocation domain (T).
(Metz, B. – 2005)
the Vaccine affects the immune system?
The vaccine helps to immunise
a patient as it allows the immune system in the body to recognise the
inactivated toxin and allows it to build a defence against it. By
administrating the vaccine intramuscular it allows the inactivated toxin to
enter the blood stream straight away meaning that the inactivated toxoid has
completely bypassed the normal line of immune system defence – through mouth
nose or skin.
All Diphtheria vaccine contain
aluminium as an adjuvant. Adjuvant are neurotoxins that trigger the required
immune response. This adjuvant alarms the immune system causing it to react to
everything in the vaccine, therefore the inactivated toxoid, which then allows
the body to develop the required antibodies against toxoid. (Vaccinedecision.info. (2018))
That are affected by the Vaccine:
Diphtheria infects the throat, nose and larynx, the toxin
can also affect the heart, kidneys, liver, lungs, nerves and muscles, therefore
the vaccine will need to affect the lymphatic system to allow the immune system
to work and also the organs that are affected by the toxin so therefore no
symptoms can occur.
Uptake of Diphtheria Vaccine (UK):
In the UK children receive three primary doses of Diphtheria for
full immunisation to occur. The WHO target of 95% means that if 95% of the
population is vaccinated that means that the whole nation will be immune to the
Toxin. 93.4% of children in the UK were vaccinated which was a slight drop from
2015-16 of 93.6%. In the year 2012-13 94.7% of children at 12 months had their
primary treatment of the 5-in-1 vaccine.
Immunisations Team, NHS Digital. (2017))
The effectiveness of Vaccine:
The Diphtheria vaccine has been very
effective in recent years in many countries. In the UK nearly 95% of babies at
12 months have the vaccine which has made Diphtheria very rare in the UK.
However recently the number of cases of Diphtheria in the Russian Federation
rose during 1991-1992 with 319 respiratory diphtheria cases in children between
the ages of 6 years to 14 years. Control subjects at that time received more
doses of the vaccine. The results that were taken during that time shows that
the vaccine was very effective even if one dose was taken. (Bisgard, K et al –