Whooping cough--a continuing problem

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                        cases.10 The competing demands of general practice                     KK has received fees for speaking and research from Pfizer and
                        must be explicitly addressed if we are to enable the                   Eli Lilly.
                        general practitioner to practise psychological medicine
                        effectively.11                                                         1  Ormel J, Von Korff M, Ustun TB, Pini S, Korten A, Oldehinkel T.
                                                                                                  Common mental disorders and disability across cultures: results from the
                            Yet this approach is no different to what is also                     WHO collaborative study on psychological problems in general health
                        required for many chronic medical disorders such as                       care. JAMA 1994;272:1741-8.
                                                                                               2 Kroenke K. Studying symptoms: sampling and measurement issues. Ann
                        diabetes, asthma, and heart disease, for which it has                     Intern Med 2001;134:844-55.
                        been proved that care in concordance with guidelines                   3 Reid S, Wessely S, Crayford T, Hotopf M. Medically unexplained
                                                                                                  symptoms in frequent attenders of secondary health care: retrospective
                        requires appreciable reorganisation of medical serv-                      cohort study. BMJ 2001;322:1-4.
                        ices.12 Neither chronic medical nor “psychiatric” disor-               4 Wessely S, Nimnuan C, Sharpe M. Functional somatic syndromes: one or
                                                                                                  many? Lancet 1999;354:936-9.
                        ders can be managed adequately in the current                          5 O’Malley PG, Jackson JL, Santoro J, Tomkins G, Balden E, Kroenke K.
                        environment of general practice, where the typical                        Antidepressant therapy for unexplained symptoms and symptom
                                                                                                  syndromes. J Fam Pract 1999;48:980-90.
                        patient must be seen in 10-15 minutes or less. The                     6 Kroenke K, Swindle R. Cognitive-behavioral therapy for somatization
                        quick visit may work for the patient with a common                        and symptom syndromes: a critical review of controlled clinical trials. Psy-
                                                                                                  chother Psychosom 2000;69:205-15.
                        cold or a single condition, such as well controlled                    7 Sharpe M, Carson A.“Unexplained”somatic symptoms, functional
                                                                                                  syndromes, and somatization: do we need a paradigm shift? Ann Intern
                        hypertension, but will not suffice for the prevalent and                  Med 2001;134:926-30.
                        disabling symptoms and disorders comprising psycho-                    8 Von Korff M, Moore JC. Stepped care for back pain: activating
                                                                                                  approaches for primary care. Ann Intern Med 2001;134:911-7.
                        logical medicine. Evidence based treatments exist.                     9 Kroenke K, Taylor-Vaisey A, Dietrich AJ, Oxman TE. Interventions to
                        Using them in a way that is integrated with general                       improve provider diagnosis and treatment of mental disorders in
                                                                                                  primary care: a critical review of the literature. Psychosomatics 2000;41:39-
                        practice will improve our patients’ physical health and                   52.
                        psychological wellbeing.                                               10 Rubenstein LV, Jackson-Triche M, Unutzer J, Miranda J, Minnium K,
                                                                                                  Pearson ML, et al. Evidence-based care for depression in managed
                                                                                                  primary care practices. Health Aff 1999;18:89-105.
                        Kurt Kroenke professor of medicine                                     11 Klinkman MS. Competing demands in psychosocial care: a model for the
                                                                                                  identification and treatment of depressive disorders in primary care. Gen
                        Department of Medicine, Regenstrief Institute for Health Care, RG-6,      Hosp Psychiatry 1997;19:98-111.
                        1050 Wishard Blvd, Indianapolis, IN 46202, USA                         12 Wagner EH, Austin BT, Von Korff M. Organizing care for patients with
                        kkroenke@regenstr ief.org                                                 chronic illness. Milbank Q 1996;74:511-44.

                        Whooping cough—a continuing problem
                        Pertussis has re-emerged in countries with high vaccination coverage and
                        low mortality

                                  ews media announced a global resurgence of                   strains that has led to a fall in vaccine efficacy.5 Similar
                                  whooping cough in April this year following a                studies in other countries have also revealed the emer-
                                  session on pertussis at the 12th European                    gence of non-vaccine variants of pertactin and pertus-
                        Congress of Clinical Microbiology and Infectious Dis-                  sis toxin.6 In France, however, an increase in the
                        eases in Milan, Italy. Subsequently the European Union                 frequency of non-vaccine variants of both pertussis
                        sent an alert to member states. Pertussis is one of the                and pertactin toxin has not been accompanied by a
                        top causes of vaccine preventable deaths, with nearly                  decline in the efficacy of the vaccine.7 The situation in
                        300 000 deaths in children worldwide in 2000.1                         the United Kingdom, where there has not been a
                        However, reports of a global resurgence originated in                  re-emergence of pertussis, seems unique in that all of
                        countries with low mortality and high vaccination cov-                 the most recent isolates studied are of the same pertus-
                        erage. For such countries the issue is how to fine tune                sis toxin type as one of the strains included in the
                        effective immunisation programmes. In the rest of the                  United Kingdom whole cell vaccine.8
                        world, priorities are to decrease infant mortality by                      In high coverage countries, further development of
                        improving coverage and timeliness of vaccination and                   national policies for the control of pertussis is a
                        implementing pertussis surveillance.2                                  challenge because of underdiagnosis and under-
                            Pertussis has re-emerged in low mortality countries                reporting, which hinder surveillance, as well as gaps in
                        in the past because of low coverage after a vaccine                    our knowledge of levels of herd immunity generated
                        scare in the 1980s (in the United Kingdom) or the use                  by the vaccination programmes. Underdiagnosis
                        of vaccines with poor efficacy (Canada, Sweden).3 Swe-                 occurs because pertussis has mild or atypical forms,
                        den and Germany stopped their vaccination pro-                         because clinicians may not consider pertussis as a
                        grammes completely and only reinstituted vaccination                   cause of cough especially in older children and adults,
                        for pertussis after years of recurrent epidemics of                    or because sensitivity of culture, the traditional
                        whooping cough. More recently some countries with                      diagnostic method, is as low as 20-40%. Surveillance is
                        sustained high coverage have experienced increases in                  so incomplete that enhanced awareness or improved
                        pertussis, especially in older children and adults, the                diagnostic methods can result in apparent epidemics,
                        reasons for which are complex.3 4 After an outbreak of                 which may account for some of the observed increase
                        pertussis in the Netherlands in 1996, polymorphisms                    in older individuals in several countries with high vac-
                        in the genes coding for the Bordetella pertussis virulence             cination coverage.4 5 Methods such as enzyme linked
                        factors pertactin and pertussis toxin were reported as                 immunoassay (ELISA) based serology and polymerase
BMJ 2002;324:1537–8     evidence for a vaccine driven evolution of circulating                 chain reaction have increased diagnostic sensitivity and

BMJ VOLUME 324        29 JUNE 2002   bmj.com                                                                                                                            1537

have only recently become routinely available in some                         2  World Health Organization. Department of Vaccines and Biologicals.
                                                                                 Pertussis surveillance. A global meeting. WHO/V&B/01.19. Geneva,
countries, such as from the Public Health Laboratory                             2001.
Service for England and Wales. Improved surveillance                          3 Skrowronski DM, De Serres G, MacDonald D, Wu W, Shaw C, Macnabb J,
                                                                                 et al. The changing age and seasonal profile of pertussis in Canada. J Infect
will help evaluate the impact of interventions including                         Dis 2002;185:1448-53.
the preschool booster implemented in the United                               4 Mooi FR, Van Oirschot H, Heuvelman K, Van der Heide HGJ, Gaastra W,
                                                                                 Willems RJL. Polymorphism in the Bordetella pertussis virulence factors
Kingdom in November 2001.                                                        P.69/pertactin and pertussis toxin in the Netherlands: Temporal trends
    Infants are at greatest risk of death or severe com-                         and evidence for vaccine-driven evolution. Infect Immunity 1998;66:670-5.
                                                                              5 Yih WK, Lett SM, des Vignes FN, Garrison KM, Sipe PL, Marchant CD.
plications from pertussis.9 We rely on herd immunity                             The increasing incidence of pertussis in Massachusetts adolescents and
to protect the youngest infants before they can be                               adults 1989-98. J Infect Dis 2000;182:1409-16.
protected directly by vaccination. However, in contrast                       6 Gzyl A, Augustynowicz E, van Loo I, Slusarczyk. Temporal nucleotide
                                                                                 changes in pertactin and pertussis toxin genes in Bordetella pertussis
to diseases such as measles, pertussis vaccination may                           strains isolated from clinical cases in Poland. Vaccine 2002;20:299-303.
have an only limited impact on interrupting transmis-                         7 Njamkepo E, Rimlinger F, Thiberge S, Guiso N Thirty-five years’ experi-
                                                                                 ence with the whole-cell pertussis vaccine in France: vaccine strains
sion. The interepidemic period has not increased                                 analysis and immunogenicity. Vaccine 2002;20:1290-4.
markedly on implementation of vaccination pro-                                8 Fry NK, Neal S, Harrison TG, Miller E, Matthews R, George RC.
                                                                                 Genotypic variation in the Bordetella pertussis virulence factors
grammes, so the vaccine may be more effective at pre-                            pertactin and pertussis toxin in historical and recent clinical isolates in
venting disease than infection. Furthermore, vaccine                             the United Kingdom. Infect Immun 2001;69:5520-8.
                                                                              9 Ranganathan S, Tasker R, Booy R, Habibi P, Nadel S, Britto J. Pertussis is
derived immunity wanes over five to 10 years so that                             increasing in unimmunized infants: is a change in policy needed? Arch
pertussis occurs in older vaccinated individuals who                             Dis Child 1999;80:297-9.
                                                                              10 Fine PE, Clarkson JA. Reflections on the efficacy of pertussis vaccines. Rev
may then infect infants. Consequently, unvaccinated                              Infect Dis 1987;9:866-3.
infants remain at risk of pertussis despite good vacci-                       11 Edmunds WJ, Brisson M, Melegaro A, Gay NJ. The potential
                                                                                 cost-effectiveness of acellular pertussis booster vaccination in England
nation programmes.10 Uncertainty about the level of                              and Wales. Vaccine 2002;20:1316-30.
herd immunity generated by vaccination programmes                             12 Senzilet LD, Halperin SA, Spika JS, Alagaratnam M, Morris A, Smith B,
                                                                                 et al. Pertussis is a frequent cause of prolonged cough illness in adults and
limits modelling of the potential benefits of booster                            adolescents. Clin Infect Dis 2001;32:1691-7.
vaccination.11 Policy makers need more information
about the natural history of pertussis in adolescents
and adults to determine the potential benefits from                           We ask all editorial writers to sign a declaration of competing interests
                                                                              (bmj.com/guides/confli.shtml#aut). We print the interests only
booster vaccination in these groups irrespective of any                       when there are some. When none are shown, the authors have ticked the
possible benefit to infants through reducing transmis-                        ‘‘None declared’’ box.
sion. In view of the limits of surveillance, the answers
to specific policy questions may require focused stud-
ies in representative populations of the incidence and                        Correction
source of infection in young infants, the incidence and                       Are selective COX 2 inhibitors superior to traditional
severity of undiagnosed pertussis in adults, and the                          non-steroidal anti-inflammatory drugs?
number of deaths from pertussis particularly in high                          We regret that fig 2 in this editorial by Peter Jüni et al (1 June,
mortality countries.2 11 12                                                   pp 1287-8) had mislabelled axes. The vertical axis should
    For most countries in the world, discussing the pos-                      have read “Cumulative percentage” and the horizontal axis
sible costs and benefits of adolescent and adult pertus-                      should have had 0-12 months on it, as below.
sis boosters and molecular diagnostic methods are not
a priority. The global priorities remain enabling social,                                             1.0
                                                                              Cumulative percentage

political, and economic stability that are prerequisites
for health services capable of delivering high coverage
and safe, timely vaccination for all children.2 Pertussis
vaccination has the potential to prevent an additional
third of a million deaths globally every year. In 2000                                                0.4
the World Health Organization held its first meeting                                                                                                 Celecoxib
on surveillance of pertussis in 20 years.2 The                                                        0.2                                            Diclofenac
participants concluded that pertussis had been
neglected as a disease, that research on deaths from                                                   0
                                                                                                            0      3           6          9            12
pertussis should be carried out in high mortality coun-                                                                                         Months of follow up
tries, and that basic laboratory surveillance and control                     Fig 2 Kaplan-Meier estimates for ulcer complications according to
measures need strengthening globally.                                         traditional definition. Results are truncated after 12 months, no ulcer
                                                                              complications occurred after this period. Adapted from Lu 2001.7
N S Crowcroft consultant epidemiologist
Immunisation Division, Public Health Laboratory Service
Communicable Disease Surveillance Centre, London NW9 5EQ
                                                                                                       What is a good doctor and how can we make one?
Joseph Britto honorary senior lecturer in paediatric
                                                                                                       We want your views on this for a future theme issue of the BMJ.
intensive care                                                                                           Governmental and professional regulation now operates in most
Department of Paediatrics, Imperial College School of Medicine at                                      aspects of doctors’ lives, yet doctors themselves have had little
St Mary's Hospital, London W2 1NY                                                                      opportunity to air their views on what they think makes a good doctor
The authors acknowledge helpful comments from Mike Levin,                                              or how good doctors should be made.
Norman Fry, Tim Harrison, and Kwame McKenzie.                                                            Contribute to this debate now by visiting our home page (bmj.com) or
                                                                                                       going direct to the debate at www.bmj.com/gooddoctor
                                                                                                         All submissions will be published on the website and a selection of the
1   World Health Organization. World Health Report 2001. Mental health: new
                                                                                                       best letters will be published in the theme issue that will be devoted to
    understanding,   new    hope.   www.who.int/whr/2001/main/en/pdf/                                  this topic in September 2002.
    annex2.en.pdf (accessed 7 Jun 2002).

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