Vaccination Doubles Asthma Incidence
One Click Note: The World Health Organisation states that for every
1000 children vaccinated with the pneumococcal vaccine, 1.3 children will
develop asthma on account of the vaccine. At the same time only 3.6 cases of
pneumonia are prevented by vaccinating 1000 children. Pneumonia is a easily
treated condition. Asthma on the other hand may be a lifelong disability.
Incidence of pneumonia is not reduced by pneumococcal
Publication: Bulletin of the World Health Organization;
Article DOI: 10.2471/BLT.08.054692
Sona Chowdhary & Jacob PuliyelDepartment of Pediatrics,
St Stephens Hospital,
Correspondence to Jacob Puliyel (e-mail: email@example.com).
(Published online: 1 September 2008)
Madhi et al.1 write that the pneumococcal conjugate vaccine (PCV) is an
effective instrument for pneumonia prevention in children. This is not strictly
true. WHO data2 suggest that there are 450 million cases of pneumonia each year
and that it causes 3.9 million deaths. In the sub-Saharan region of Africa, 1
022 000 die and 702 000 die in south Asia.1 The pneumonia referred to is
“clinical pneumonia” – a diagnostic syndrome within the Integrated Management of
Childhood Illness – WHO and United Nations Children’s Fund (UNICEF) system for
triage and clinical management in developing countries.3 The Cochrane database4
states that PCV does not reduce the incidence of clinical pneumonia, although it
has been shown to reduce vaccine-serotype bacteraemic pneumonia and radiological
pneumonia. The benefit of reducing bacteraemic pneumonia and radiological
pneumonia is so minimal that it has no effect on “clinical pneumonia”. Poor
nations will need to assess its cost utility carefully.
A study from the Gambia showed that mortality was 16% lower in a PCV immunized
group compared to placebo recipients (25.2/1000 children years versus 30.1/1000
children years).5 Data are also provided on adverse effects and deaths within 1
week of receiving any dose of the vaccine or placebo. The mortality benefit was
seen in the first week after injection, well before vaccine efficacy could have
been established. There were 12 deaths in the vaccine group and 15 among
controls (23.8/1000 children years versus 29.8/1000 children years). This
suggests that factors other than vaccine efficacy are responsible for the
difference in mortality between the groups compared.
There is also another issue that we hope to raise here. The paper states that
the vaccine programme would exceed the WHO threshold in 69 eligible countries.
The authors assert that these findings are conservative in the sense that they
did not assume any herd protection and did not assume protection beyond the age
of 2.5 years. Beutels6 has cautioned against this trend of noting the “positive”
uncertainties (herd immunity, protection beyond 2.5 years) without reporting the
“negative” ones (serotype replacement,7 increased incidence of asthma),8 which
could dampen enthusiasm for the intervention.
1. Madhi SA, Levine OS, Hajjeh R, Mansoor OD, Cherian T. Vaccines to prevent
pneumonia and improve child survival. Bull World Health Organ 2008;86:365-372.
2. Revised global burden of disease 2002 estimates. Geneva: WHO. Available here
[accessed 5 August 2008].
3. Integrated Management of Childhood Illness. Geneva: WHO; 2000.
4. Lucero MG, Dulalia VE, Parreno RN, Lim-Quianzon DM, Nohynek H, Makela H, et
al. Pneumococcal conjugate vaccines for preventing vaccinetype invasive
pneumococcal disease and pneumonia with consolidation on x-ray in children under
two years of age. Cochrane Database Syst Rev 2004;CD004977. PMID:15495133
5. Cutts FT, Zaman SM, Enwere G, Jaffar S, Levine OS, Okoko JB, et al.; Gambian
Pneumococcal Vaccine Trial Group. Efficacy of nine-valent pneumococcal conjugate
vaccine against pneumonia and invasive pneumococcal disease in The Gambia:
randomised, double-blind, placebo-controlled trial. Lancet 2005;365:1139-46.
6. Beutels P. Potential conflicts of interest in vaccine economics research: a
commentary with a case study of pneumococcal conjugate vaccination. Vaccine
7. Eskola J, Kilpi T, Palmu A, Jokinen J, Haapakoski J, Herva E, et al.; Finnish
Otitis Media Study Group. Efficacy of a pneumococcal conjugate vaccine against
acute otitis media. N Engl J Med 2001;344:403-9. PMID:11172176
8. Klugman KP, Madhi SA, Huebner RE, Kohberger R, Mbelle N, Pierce N; Vaccine
Trialists Group. A trial of a 9-valent pneumococcal conjugate vaccine in
children with and those without HIV infection. N Engl J Med 2003;349:1341-8.