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A Practical Guide to Immunisation
People who develop chronic infection are at increased risk of developing chronic hepatitis, cirrhosis
and liver cancer. Premature death from chronic liver disease occurs in 15-25% of chronically
infected people.
Vaccine schedule in Ireland
Prior to 2007, immunisation was recommended for high risk groups including healthcare workers,
those with chronic hepatitis and spouses, sexual partners, family and household contacts of acute
cases and carriers of hepatitis B virus.
In 2007, following a review of the epidemiology of hepatitis B infection in Ireland by the National
Immunisation Advisory Committee (NIAC) and supported by a pharmacoeconomical evaluation,
hepatitis B vaccination was recommended as part of the primary childhood immunisation
programme. The vaccine is administered at 2, 4 and 6 months with diphtheria, tetanus, whooping
cough (pertussis), Hib and IPV vaccines (referred to as the “6-in-1” vaccine).
Vaccination will also continue for those high-risk groups as outlined by NIAC.
4.2.4 Measles
Epidemiology of disease and impact of vaccination
Measles is an extremely infectious viral illness caused by the Morbillivirus. Measles occurs most
commonly in the non-immunised 1-4 year old age group.
16000
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Mea s les Va ccine, 1985
Number of Notifications
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MR , 1995
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Figure 4.4: Measles cases reported in Ireland 1948-2006
Source: Health Protection Surveillance Centre
Measles has been notifiable in Ireland since 1948 (Figure 4.4). The highest number of cases was
recorded in 1959 when 15,124 cases were notified. In 1985 the measles vaccine was introduced
into the Irish immunisation schedule. The number of reported cases in the immediate subsequent
years dropped significantly, so that by 1991 just 135 cases were reported. However, a number of
major outbreaks have occurred despite the routine immunisation programme.
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A Practical Guide to Immunisation
Clinical features
The first stage of measles includes irritability,
runny nose, conjunctivitis (red eyes), hacking
cough and fever. These symptoms may last
up to eight days.
The typical measles rash starts from day four,
beginning at the hairline and progressing
downwards over the face, neck and body.
The rash consists of flat red or brown
blotches, which can flow into each other and
lasts 4-7 days. Small white spots are also
found inside the cheeks (Koplik’s spots).
The patient may also experience diarrhoea,
vomiting and abdominal pain.
Photo courtesy of CDC
The combined Measles, Mumps and Rubella (MMR) vaccine was introduced in 1988 and a second
dose MMR was introduced in 1992 at 10-14 years. Following an outbreak in 1993 (4,328 cases) a
Measles-Rubella (MR) campaign was introduced in 1995 and in 1999 the age group for the second
dose of MMR was lowered to 4-5 years.
However, concerns about vaccine safety kept uptake levels below the 95% uptake rate required for
herd immunity, resulting in further outbreaks in 2000 and 2003. In 2000, 1603 cases occurred in
Ireland. There were three deaths in children - two children died of pneumonia complicating measles
and one child later died from post measles encephalitis.
Transmission
Measles is one of the most highly infectious communicable diseases. Measles is transmitted by
airborne droplet spread e.g. when the infected person coughs or sneezes, or through direct contact
with nasal or throat secretions of an infected patient.
Incubation period
The incubation period is generally about ten days but can range from 7-21 days.
Period of infectivity
A patient is infectious from beginning of first symptoms (usually about four days before onset of
rash) to four days after appearance of the rash.
Measles complications occur in approximately 30% of reported cases. It is estimated that one in
100 infected require hospital admission. Complications are generally more common in babies, older
children, adults and the immunocompromised. Complications include
Ear infection
Pneumonia /Bronchitis
Convulsion
Diarrhoea
Meningitis/encephalitis
Late onset SSPE (progressive irreversible brain degeneration)
Death
Chapter 4: Vaccine Preventable Diseases
(affects
(affects
(affects
(affects
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(affects
1
1
1
1
1
1
in
in
in
in
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20)
25)
200)
6)
1000)
8,000 children under 2 years)
(affects 1 in 2,000)
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A Practical Guide to Immunisation
Vaccine schedule in Ireland
Measles immunisation with the combined MMR vaccine is recommended for all children at 12
months as part of the primary childhood immunisation programme. A booster dose of MMR
vaccine is recommended at 4-5 years. Single vaccines are not recommended.
Measles and Autism
In 1998, a study of autistic children raised the question of a connection between MMR vaccine and
autism. This study has a number of limitations and involved only 12 children. In 2004, 10 of the 13
authors of the 1998 study retracted the conclusions of the study and stated that the data was not
able to establish a causal link between MMR vaccine and autism. Since then several larger studies
have found no relationship between MMR vaccine and autism.
Measles Elimination
The World Health Organisation European Region has prepared a strategic plan (2005-2010) to
eliminate measles and rubella and prevent congenital rubella by 2010. The strategy includes
ensuring that all children will have the opportunity to receive two doses of MMR vaccine.
4.2.5 Meningococcal disease
Epidemiology of disease and impact of vaccination
Meningococcal disease is caused by the bacterium Neisseria meningitidis of which there are several
subtypes (A, B, C, Y, W135, X). Invasive meningococcal disease (meningitis or septicaemia) may
occur at any age but is most common in infancy and early childhood with an additional smaller
peak of disease activity in adolescents and young adults. In temperate climates such as Ireland the
infection typically shows a seasonal variation with the majority of cases occurring in winter and early
spring.
Meningococcal vaccines have been available since the 1970s. However, the original polysaccharide
vaccines did not provide long-term protection and were not effective in children under 24 months.
New meningococcal C conjugate vaccines have been developed from purified capsular
polysaccharides and are effective under 18 months of age and provide longer immunity. Prior to
introduction of meningococcal C vaccine into the Irish Immunisation Schedule in 2000, serotype B
and C infections were common in Ireland.
The introduction of meningococcal C vaccine has led to a reduction in the number of cases of
meningococcal disease and in deaths due to meningococcal disease (Figure 4.5).
Other serotypes are more common in some parts of the world e.g. Group A in sub-Saharan Africa
and W135 in Saudi Arabia.
Transmission
Transmission occurs through frequent and prolonged contact with respiratory secretions of a carrier
from coughing, sneezing, and mouth-kissing. Depending on the age group, up to 1 in 10 people
may carry these bacteria. Carriage is uncommon in infancy and early childhood but increases with
age. Peak carriage rates may occur in the 15-19 year old group of whom 25% may be carriers.
Carriage is typically followed by the development of immunity.
Incubation period
The incubation period ranges between 2-10 days.
Period of infectivity
Individuals are infectious as long as meningococcal bacteria are present in the nose and mouth.
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