Prevalence of vaccine-preventable infections among HIV-infected children in the UK and Ireland over 13 years, 1996-2008

1. Prevalence of vaccine-preventable infections among HIV-infected children in the UK and Ireland over 13 years, 1996-2008 H Payne1, K Donegan2, I Okike1, D Gibb2, K Doerholt1, PT Heath1. 1. St George’s Hospital NHS Trust, London; 2. Clinical Trials Unit, Medical Research Council, London. Results Aims and background Hospitalisations for vaccine-preventable infections as a % of all paediatric hospitalisations for children in the CHIPS cohort To define the burden of vaccine-preventable infections among HIV-infected children in the UK and Ireland and to consider the implications for vaccination guidelines. Vaccines are an excellent tool for preventing potentially life-threatening diseases in all children. Children with HIV are more likely to require hospital admission and suffer serious effects of several infections for which vaccines are available. Studies have demonstrated vaccine safety in immune-compromised children and the ability to mount protective responses to pneumococcal1 and varicella2 vaccinations. Administration of these vaccines, in addition to the standard UK immunization schedule, is recommended for HIV-infected children. However, a 2009 audit of vaccine coverage among HIV-infected children attending several London clinics revealed that rates of immunization were low with only 28% and 0% receiving pneumococcal and varicella vaccines respectively3 . Varicella Pneumococcus Incidence rate for hospitalisations compared to “healthy” children (www.hpa.org.uk) Methods The Collaborative HIV Paediatric Study (CHIPS) CHIPS is a multicentre cohort of HIV-infected children under care in the UK and Ireland since 1996. Children are managed at 67 hospitals in the UK and Ireland and account for approximately 95% of all children reported to the National Study of HIV in Pregnancy and Childhood (NSHPC). Microbiological  confirmation was obtained for cases of pneumococcal disease by direct contact with the relevant clinician. Statistical Methods Demographic and clinical baseline data are described. Hospitalisation data are routinely collected for HIV-infected children in CHIPS follow up and were analysed for admissions due to vaccine preventable diseases (VPD): pneumococcal (IPD) and varicella infections (V) (including chicken pox (CP) or zoster (Z)) during 1996-2008, with additional retrospective data from 1992. Results Summary 1571 children reported to CHIPS were in follow up to 31st Dec 2008 with a total of 3761 hospital admissions; 18 and 187 hospitalisations were due to IPD or V respectively (80 admissions due to Z and 107 due to CP). Serotype data were available for 4 cases of IPD: 23F x 2, 1 of 9V, 1 of 19F (all present in PCV7). Table 1 describes baseline and clinical demographics of children with and without IPD and V- related hospital admissions. • The incidence of hospitalisations for pneumococcal or varicella disease in HIV-infected children suggests a considerable burden of morbidity from potentially vaccine-preventable infections in this group. • The majority of this burden is due to chicken pox or herpes zoster. • Formal definition of the risk factors for hospitalisation among HIV-infected children will be undertaken using a case control analysis but it appears that compared with children not hospitalised: • CDC classification was lower at HIV diagnosis and commencement of HAART in children who have subsequently been admitted with a VPD. • A significant minority (12%) admitted with IPD were on HAART at that time. • These data will also be used to update national vaccination guidelines to ensure that pneumococcal and varicella vaccinations are offered to all HIV-infected children. • Subsequent evaluation will assess the impact of these guidelines. Acknowledgements Funding: NSHPC is funded by the Health Protection Agency, and has also received support from the UK Department of Health and the Medical Research Council. CHIPS is funded by the Department of Health and in the past received additional support from Bristol-Myers Squibb, Boehringer Ingelheim, GlaxoSmithKline, Roche, Abbott, and Gilead. Committees and participants (in alphabetical order): CHIPS Steering Committee: K Butler, K Doerholt, S Donaghy, DT Dunn, T Duong, DM Gibb, A Judd, EGH Lyall, J Masters, E Menson, V Novelli, C Peckham, A Riordan, M Sharland, D Shingadia, PA Tookey, G Tudor-Williams, G Wait MRC Clinical Trials Unit: DT Dunn, T Duong, L Farrelly, DM Gibb, D Johnson, A Judd, G Wait, AS Walker National Study of HIV in Pregnancy & Childhood, Institute of Child Health: J Masters, C Peckham, PA Tookey We thank the staff, families & children from the following hospitals who participate in CHIPS (in alphabetical order): Republic of Ireland:Our Lady's Children’s Hospital Crumlin, Dublin: K Butler, A Walsh. UK: Birmingham Heartlands Hospital, Birmingham: Y Heath, J Sills; BlackpoolVictoria Hospital, Blackpool: N Laycock; Bristol Royal Hospital for Children, Bristol: A Finn, A Foot,L Hutchison; Central Middlesex Hospital, London: M Le Provost, A Williams; Chase Farm Hospital, Middlesex; Chelsea and Westminster Hospital, London: D Hamadache, EGH Lyall, P Seery; Ealing Hospital, Middlesex: V Shah, KSloper; GlasgowRoyal Hospital for Sick Children, Glasgow: C Doherty, R Hague; Great Ormond St Hospital for Children, London: M Clapson, S Fasolo, J Flynn, DM Gibb, N Klein, K Moshal, V Novelli, D Shingadia; Hillingdon Hospital, London; Homerton University Hospital, London: D Gurtin; John Radcliffe Hospital, Oxford: A Pollard, S Segal; King's College Hospital, London: C Ball, S Hawkins, D Nayagam; Leeds General Infirmary, Leeds: P Chetcuti; Leicester Royal Infirmary, Leicester: M Green, J Houghton; Luton and Dunstable Hospital, Luton: M Connan, M Eisenhut; Mayday University Hospital, Croydon: J Baverstock, J Handforth; Milton Keynes General Hospital, Milton Keynes: PK Roy; Newcastle General Hospital, Newcastle: J Clarke, K Doerholt, C Waruiru; Newham General Hospital, London: C Donoghue, E Cooper, S Liebeschuetz, S Wong; Ninewells Hospital and Medical School, Dundee: T Lornie; North Manchester General Hospital, Manchester: C Murphy, T Tan; North Middlesex Hospital, London: J Daniels, EGH Lyall, B Sampson-Davis;Northampton General Hospital, Northampton: F Thompson; Northwick Park Hospital, Middlesex; M Le Provost, A Williams; Nottingham City Hospital, Nottingham: D Curnock, A Smyth, M Yanney; Queen Elizabeth Hospital, Woolwich: W Faulknall, S Mitchell; Royal Belfast Hospital for Sick Children, Belfast: S Christie; Royal Edinburgh Hospital for Sick Children, Edinburgh: J Mok; Royal Free Hospital, London: S McKenna, V Van Someren; Royal Liverpool Children’s Hospital, Liverpool: C Benson, A Riordan; Royal London Hospital, London: B Ramaboea, A Riddell; Royal Preston Hospital, Preston: AN Campbell; Sheffield Children's Hospital, Sheffield: J Hobbs, F Shackley; St George's Hospital, London: R Chakraborty, S Donaghy, R Fluke, M Sharland,S Storey, C Wells; St Mary's Hospital, London: D Hamadache, C Hanley, EGH Lyall, G Tudor-Williams, C Walsh, S Walters; St Thomas' Hospital, London: R Cross, G Du Mont, E Menson; University Hospital Lewisham, London: D Scott, J Stroobant; University Hospital of North Staffordshire, Stoke On Trent: P McMaster;University Hospital of Wales, Cardiff: B O' Hare; Wexham Park, Slough: R Jones; Whipps Cross Hospital, London: K Gardiner; Whittington Hospital, London. References 1) Abzug et al. Immunogenicity, Safety, and Predictors of Response After a Pneumococcal Conjugate and Pneumococcal Polysaccharide Vaccine Series in Human Immunodeficiency Virus-Infected Children Receiving Highly Active Antiretroviral Therapy. PIDJ 2006;25:920-9. 2) Wood et al. Primary Varicella and Herpes Zoster Among HIV-Infected Children From 1989 to 2006 Ped 2008;121:150-156. 3) Bamford A et al, ESPID 2009 poster: Immunisatin status of children with HIV: Failure to protect a vulnerable population. Contact: Dr Katja Doerholt, St Georges Hospital, London. Tel:+44 (0) 20 87253262 Email: katja.doerholt@stgeorges.nhs.uk