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Pneumonia
a major killer in children; prevention possible with safe & effective
vaccines
Pneumonia is the leading
single cause of childhood mortality. The disease accounts for 19 per cent
deaths in children less than 5 years. Pneumonia kills more children than any
other illness, more than measles, malaria and AIDS combined. Globally 156
million new pneumonia cases are reported every year in the developing world.
As many as 8.7 per cent of these cases are severe enough to be
life-threatening and require hospitalization. India
accounts for the maximum 43 million new cases followed by China (21 million cases) and Pakistan (10
million cases). Pneumonia is estimated to kill 410,000 children in India
every year.
Haemophilus
influenza and Streptococcus pneumonia are the main causes of bacterial
pneumonia and estimated to be the causative organisms for more than 50% of
all childhood pneumonias. In addition some diseases, like measles and pertussis (whooping cough) can lead to pneumonia as a
complication.
It has been shown through
various studies that mortality due to pneumonias could be decreased by
interventions like prevention of pneumonia through immunization, early diagnosis
and optimal case management, exclusive breastfeeding for six months, reducing
indoor air pollution, preventive antibiotic treatment in HIV infected children and zinc supplementation.
Prevention of pneumonia
through immunization:
In India, pneumonia is responsible
for an estimated 410,000 deaths in children under five and a substantial
proportion of these deaths are due to pneumococcal
pneumonia. While treatment with
antibiotics reduces mortality, lack of access to care and delay in provision
of antibiotics, especially among the poor and most vulnerable children result
in high case fatality from pneumonia.
Studies have shown that up to 19% of children hospitalized with
pneumonia die in India.
Another consideration is the rising resistance to commonly used antibiotics
worldwide associated with increasing rates of treatment failures. Hence,
prevention of Pneumonia through immunization is an effective way to decrease
the incidence and prevent mortality and morbidity in children. Among
immunizations, introduction of Haemophilus
influenza (Hib) and Pneumococcal
vaccines (PCV) and improving immunization coverage of Measles and Pertussis vaccine have been shown to decrease the
incidence of Pneumonia in children under 5 years of
age.
Taking into consideration all
the evidence presented, the National Technical Advisory Group (NTAGI) on
Immunization recommended the national roll out of Hib
vaccine by 2012 as a multi-dose liquid pentavalent
vaccine (DPT-Hep B-Hib).
Concerning pneumococcal vaccine, the NTAGI recognizing
the need for its introduction, recommended a vaccine impact study on the 7 valent Pneumococcal vaccine
(PCV 7) in one high mortality state be initiated as early as possible.
Hib
and Pneumococcal vaccines are safe and
cost-effective vaccines and are instrumental in preventing serious and fatal
pneumonia in young children under 5 years of age. WHO recommends prioritizing the use of
vaccines, as millions of children, specially the poor,
remain at high risk of dying from pneumonia. The WHO recommendations were
made after a thorough review of all available data on the disease and
potential vaccine impact by expert committees and the WHO Strategic Advisory
Group of Experts (SAGE). Introduction
of Hib and Pneumococcal
conjugate vaccines into the childhood immunization programmes,
especially in developing countries, will contribute effectively to achieving
the Millennium Development Goal of globally reducing childhood deaths by
two-thirds by 2015.
The pneumococcal
conjugate vaccines also prevent meningitis caused by pneumococcus,
one of the common causes of bacterial meningitis, which is associated with
high fatality rate (over 30% in India) and long term disabilities
like deafness, seizures, paralysis and learning disorders among
survivors. Prevention of severe
pneumonia and invasive pneumococcal diseases
through vaccination is therefore an important advance in public health.
Due to some recent concerns
on the safety of Pneumococcal vaccines, a
comprehensive review of all the safety data related to this vaccine was
conducted by the WHO Global Advisory Committee of Vaccine Safety which
concluded that “the evidence did not identify any major safety problems with
PCV7 or any other pneumococcal conjugate vaccine,
with the possible exception of reactive airway disease (wheezing), which may
bear further scrutiny as additional data become available.” The advisory
committee concluded that the risk-benefit ratio for the vaccine strongly
supports the use of the vaccine in routine immunization programmes.
PCV is currently being used
in the national immunization programmes of over 25
industrialized countries with no evidence of increase in the occurrence of
wheezing. A post-marketing
surveillance review in the U.S.A.
estimated a less than 1 case report of asthma per 1 million doses of PCV
distributed. However, like with any
vaccine, ongoing safety evaluations will further monitor this issue and
overall safety of these vaccines.
Regarding the cost of Hib and Pneumococcal vaccines,
it is recognized that the price in the private market and in industrialized
countries is relatively high at present, but past experience, for example
with the hepatitis B vaccines, shows that the cost of vaccines do decline
drastically when introduced on a large scale. At the projected public sector
prices in developing countries, these vaccines are considered highly
cost-effective and a worthy allocation even if a country were to self-finance
the procurement of the vaccine. The above pattern of ultimate reduction in
vaccine cost is also true for the cost of life-saving treatments such as for
AIDS, and which have substantially declined over time.
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