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Preventing early-onset group B Streptococcal infection in newborn babies. January 2009. Charity No. 1112065 Company Reg No 5587535. Group B Streptococcus – overview 1. Streptococcus agalactiae Group B Strep, Strep B, beta haemolytic Strep
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Preventing early-onset group B Streptococcal infectionin newborn babies January 2009 Charity No. 1112065 Company Reg No 5587535
Group B Streptococcus – overview 1 • Streptococcus agalactiae • Group B Strep, Strep B, beta haemolytic Strep • First recognised as a major perinatal pathogen in the 1970s • Incidence of GBS infection increasing in the UK Source: Health Protection Agency Charity No. 1112065 Company Reg No 5587535
Group B Streptococcus – overview 2 • Commonest cause of bacterial infection in newborn babies • Underlying rate estimated at 1:1000 newborn babies in the UK • UK research suggests actual rate 3.5 per 1000 (Luck et al, 2003) • Mortality rate approximately 11% • 50% of survivors of GBS meningitis will have neurological sequelae • Early-onset and late-onset presentation of GBS infection • Up to 90% GBS infection apparent within 48 hours of birth • Remains uniformly sensitive to penicillin • Some tolerance to other antibiotics • Clindamycin around 8% is resistant • Erythromycin around 11% is resistant Charity No. 1112065 Company Reg No 5587535
Reported cases of GBS bacteraemia in infants*, England & Wales 2000-2007 Source: Health Protection Agency, 2008 *excludes a small number of infants with imprecise age data Charity No. 1112065 Company Reg No 5587535
GBS – Colonisation • Normal flora in intestinal tract and vagina • Carriage can be intermittent • Carriage is asymptomatic • Up to 30% adults carry GBS in intestines • Up to 25% of women carry GBS in the vagina • Occasionally in the throat (around 5%) • 90% of adults do not have protective antibodies to GBS • GBS can cross intact amniotic membranes • GBS grows well in amniotic fluid • GBS survives well on skin of newborn infants • GBS colonisation at delivery – risk factor for early-onset GBS disease • Cultures late in pregnancy can predict GBS colonisation status at delivery Charity No. 1112065 Company Reg No 5587535
Testing Antenatally for GBS carriage Charity No. 1112065 Company Reg No 5587535
Options to reduce GBS infection in newborn babies • Waiting & treating babies after delivery • Too late for some & won’t prevent most GBS infection • Difficult to justify • Intravenous antibiotics in labour (IAL) • Only effective method of prevention available at present • Largest study performed in Chicago (Boyer et al. N Eng J Med 1986;314:1665) • Penicillin G recommended (Clindamycin for penicillin-allergic women) • Oral antibiotics • Don’t eradicate colonisation or reduce infection • Likely to increase resistance • Exception is GBS cultured from urine (treat with oral antibiotics and offer IAL) • Intramuscular antibiotics • Theory – reduces GBS presence ≤6 weeks, so given at 35+ weeks • One small study – poorly designed & no GBS grown in control or active group Charity No. 1112065 Company Reg No 5587535
Who should be offered intravenous antibiotics in labour (IAL)? women who have one or more risk factors (including incidental finding of GBS carriage or GBS +ve urine culture) during the current pregnancy OR women identified as GBS carriers through testing (using enriched culture media) at 35-37 weeks of pregnancy OR women identified as GBS carriers through enriched culture media testing at 35-37 weeks of pregnancy and who have one or more other risk factors OR women found to carry GBS through enriched culture media testing at 35-37 weeks of pregnancy PLUS women who have one or more other risk factors Women should be offered an informed choice Charity No. 1112065 Company Reg No 5587535
Option 1: Risk Factor ApproachIAL offered to all women with one or more risk factors • >40% of cases will still occur, since this will only prevent GBS infections where risk factors are apparent in time for IAL to be offered • Supported by RCOG Green Top Guideline No 36 • Not tested in a trial • Relatively cheap to introduce & operate (no bacteriological testing costs involved) • Relatively large amounts of antibiotics prescribed (about 30% of all women) Pros and Cons Offer intravenous antibiotics in labour (IAL) to women who have: • a previous baby with GBS infection • GBS bacteria found in the urine during the current pregnancy (which should be treated at the time of diagnosis) • GBS found on a vaginal or rectal swab during the current pregnancy • a raised temperature (≥37.8°C) during labour • preterm labour or membrane rupture (<37 completed weeks of pregnancy) • prolonged rupture of membranes(≥18 hours before delivery) Charity No. 1112065 Company Reg No 5587535
Option 2: Testing ApproachIAL offered only to women identified as GBS carriers • Up to 80% potential cases prevented • A few women will acquire carriage between testing and delivery*; some carriers will miss or decline testing and some will deliver before test result available • Not tested in a trial • ECM testing for GBS carriage not routinely or widely available in the NHS (despite being recognised as optimal by RCOG & HPA) • More expensive to introduce • Relatively large amounts of antibiotics prescribed (~30% of women) • Offer sensitive enriched culture medium (ECM) testing to all women at 35-37 weeks of pregnancy • Offer intravenous antibiotics in labour (IAL) to women identified as GBS carriers during their current pregnancy Pros and Cons * Yancey research found 4% of women with negative results at 35-37 weeks of pregnancy would become positive and 13% of women with positive results would become negative Charity No. 1112065 Company Reg No 5587535
Option 3: Combined Approach 1IAL offered to GBS carriers with a risk factor • >40% of cases will still occur – this can only prevent GBS infection where risk factors are apparent in time for IAL to be offered • A few women will acquire carriage between testing and delivery (see previous slide), some carriers will miss or decline testing and some will deliver before test result is available • Well researched • ECM testing for GBS carriage not routinely or widely available in the NHS(despite being recognised as optimal by RCOG & HPA) • More expensive to introduce • Fewer women receive antibiotics ~5% Pros and Cons • Offer all women sensitive enriched culture medium (ECM) testing at 35-37 weeks • Offer intravenous antibiotics in labour (IAL) to those identified as GBS carriers during the current pregnancywho also have one or more risk factors: • Preterm labour or membrane rupture (<37 completed weeks of pregnancy) • Prolonged rupture of membranes (≥18 hours before delivery) • Maternal pyrexia (≥ 37.8oC) • GBS from a urine culture during the current pregnancy • Previous baby with GBS infection Charity No. 1112065 Company Reg No 5587535
Option 4: Combined Approach 2IAL to GBS carriers & to women with 1+ risk factors • Most >80%potential cases prevented • Not tested in a trial • ECM testing for GBS carriage not routinely or widely available in the NHS (despite being recognised as optimal by RCOG & HPA) • Less expensive – fewer women offered sensitive testing as higher-risk women offered IAL without testing • Relatively large amounts of antibiotics prescribed (~30% of pregnant women) • Offer all women sensitive enriched culture medium (ECM) testing at 35-37 weeks • Offer intravenous antibiotics in labour (IAL) to those identified as GBS carriers during the current pregnancyplus to any with one or more risk factors: • Preterm labour or membrane rupture (<37 completed weeks) • Prolonged rupture of membranes (≥18 hours before delivery) • Maternal pyrexia (≥ 37.8oC) • GBS from a urine culture during the current pregnancy • Previous baby with GBS infection Pros and Cons Charity No. 1112065 Company Reg No 5587535
Incidence of EO and LO GBS in 3 active surveillance areas in USA Source: N Engl J Med 2000;342:15-20 & p.c. A Schuchat Charity No. 1112065 Company Reg No 5587535
UK Guidelines for Prevention: NICE Antenatal Care Guideline CG6 Oct 03 - 1 Guideline updated March 2008 - No update to GBS sections despite significant new evidence since 2003 and despite requests by a number of stakeholders. Next review due March 2010 • Don’t recommend screening as “evidence of its clinical effectiveness and cost effectiveness remains uncertain.” • All the evidence shows testing and offering intravenous antibiotics in labour (IAL) to higher-risk women is clinically effective. Where introduced, reductions of over 70% in incidence, including the US, Australia, New Zealand, Belgium, France, Spain & Italy. • The cost/benefit analysis sponsored by the HTA, published September 2007 shows current practice is not cost effective – testing low-risk women and offering IAL to high risk women was shown to be most cost effective while limiting antibiotic use (Preventative strategies for group B streptococcal and other bacterial infections in early infancy: cost effectiveness and value of information analyses. BMJ. 2007 Sep. Colbourn et al) Charity No. 1112065 Company Reg No 5587535
UK Guidelines for Prevention:NICE Antenatal Care Guideline CG6 Oct 03 - 2 Guideline updated March 2008 - No update to GBS sections despite significant new evidence since 2003 and despite requests by a number of stakeholders. Next review due March 2010 • “Pregnant women should be offered information based on the current available evidence together with support to enable them to make informed decisions about their care..” • Yet information on GBS is not widely nor routinely available. • Sensitive tests for GBS are only available privately and from a handful of NHS hospitals. • Women are not told about the availability of sensitive tests for detecting GBS late in pregnancy. How can women make an informed decision when they’re not being given the information? Charity No. 1112065 Company Reg No 5587535
UK Guidelines for Prevention: Royal College of Obstetricians & Gynaecologists 1 RCOG Green Top Guideline No 36 "Prevention of early onset neonatal Group B streptococcal disease" 2003 (currently being reviewed - due 2010) • Risk factor approach • Estimates relative risk for morbidity or mortality for recognised risk factors • Incidence assumptions significantly underestimate GBS infection, so underestimate the relative risks and overestimate the numbers needed to treat for benefit • Authors of the source of incidence figures (Heath et all, 2004) estimate under-reporting of 21-42% • Incidence figures exclude probable cases of GBS infection (Luck et al 2002), including only cases where GBS was culture-proven from a normally sterile site, eg CSF or blood • Incidence of GBS infection in babies increasing (HPA) Charity No. 1112065 Company Reg No 5587535
UK Guidelines for Prevention:Royal College of Obstetricians & Gynaecologists 2 RCOG Green Top Guideline No 36 "Prevention of early onset neonatal Group B streptococcal disease" 2003 (currently being reviewed - due 2010) • Will prevent most lethal cases of EOGBS infection when fully implemented • RCOG audit Jan 2007 shows few hospitals fully comply • Until sensitive testing is routinely available for all pregnant women, GBSS endorses these guidelines • They are a key starting position to preventing early onset GBS infection • More infections in babies could be prevented by offering sensitive testing to pregnant women Charity No. 1112065 Company Reg No 5587535
Sensitive (enriched culture medium) tests for GBS carriage using rectal & vaginal swabs should be freely available to all low-risk women at 35-37 weeks of pregnancy Pregnant women should be informed about GBS, including about testing, as a routine part of their antenatal care GBSS Recommendation: 1 • identified as GBS carriers in the current pregnancy • with ≥ 1 other risk factors (no testing required) • previous baby with GBS infection • positive urine sample during this pregnancy • preterm labour or rupture of membranes <37 completed weeks of pregnancy • prolonged rupture of membranes ≥18 hours before delivery • maternal pyrexia ≥ 37.8oC Intravenous antibiotics in labour should be offered to women: Charity No. 1112065 Company Reg No 5587535
GBSS Recommendation: 2 Pregnant women should be informed about GBS as a routine part of their antenatal care Where sensitive GBS tests are unavailable in the NHS, pregnant women should be informed how to obtain them privately Intravenous antibiotics in labour should be offered to women: • who have previously had a GBS baby • where GBS is found in the urine during the current pregnancy (also treated at diagnosis) • identified as carriers (any test method) during the pregnancy • not tested using sensitive tests but with ≥ 1 other risk factors: • Prolonged rupture of membranes ≥18 hours before delivery • Preterm labour or membrane rupture <37 completed weeks of pregnancy • Maternal pyrexia ≥ 37.8oC Until sensitive tests for GBS carriage are freely and routinely available to all women at 35-37 weeks of pregnancy: Charity No. 1112065 Company Reg No 5587535
Intrapartum Antimicrobial Prophylaxis Penicillin G • 3 g (or 5 mU) IV initially and then 1.5 g (or 2.5 mU) at 4-hourly intervals until delivery. Clindamycin • For women who are allergic to penicillin, 900 mg IV every 8 hours until delivery. Intravenous antibiotics should be given for at least 4 hours before delivery, where possible • lesser times are better than nothing and 2+ hours should give considerable reassurance. Charity No. 1112065 Company Reg No 5587535
Offer Intravenous antibiotics at the start of, and at intervals during, labour to women at raised risk of their baby developing GBS infection • One of: • Women found to carry GBS during pregnancy • GBS found in urine during pregnancy • Preterm labour or membrane rupture <37 weeks of pregnancy • Prolonged rupture of membranes ≥ 18-24 hours before delivery • Maternal pyrexia 37.8°C or higher during labour* • Two or more of above risk factors • Previous baby developed GBS infection Strongly recommend Intravenous antibiotics at the onset of, and during, labour to women at particularly high risk of their baby developing GBS infection Option 6: Intravenous Antibiotics in Labour Chart *In the presence of an epidural, a slightly raised temperature may be of less significance than in a woman without Charity No. 1112065 Company Reg No 5587535
Paediatric prevention strategy for babies born at higher risk Full work up Intravenous antibiotics Review at 48 hours Signs of possible infection in neonate or mother YES NO Full work up Intravenous antibiotics Review at 48 hours Gestational age ≤ 35 weeks of pregnancy YES NO • BABY WORK UP • FBC (Full Blood Count) • CRP(C reactive protein) x2, 12 – 24 hours apart • Blood Culture • 2 swabs – throat and periumbilical • Urine antigenOptional, according to availability and personal preference Full work up Intravenous antibiotics Review at 48 hours Maternal intravenous antibiotics pre-delivery < 4 hours YES NO No work up Baby discharged Parental awareness of early signs of infection Handout Maternal intravenous antibiotics Pre-delivery > 4 hours AND mother with no signs of infection YES Charity No. 1112065 Company Reg No 5587535
Babies Colonised with GBS • Culture results are ‘history’ • Swabs from baby • Vaginal swab at time of delivery • Antibiotic treatment for a healthy colonised baby is not indicated • Can send baby home, but ‘educate’ parents • what symptoms to watch for • what to do if they develop Charity No. 1112065 Company Reg No 5587535
Mother colonised with GBS at delivery (up to 30% of women) 50% Baby colonised with GBS 50% Newborn baby not colonised 0.6% Early-onset GBS infection septicaemia, pneumonia and/or meningitis 99.4% Asymptomatic Transmission of GBS to baby Charity No. 1112065 Company Reg No 5587535
Types of GBS infection (1) • Apparent within first 6 days of life, and usually within 12 -24 hours of delivery • Usually septicaemia with pneumonia • Typical symptoms • Grunting • Poor feeding • Lethargy • Low blood pressure • Irritability • Low blood sugar • Even with the best medical care, 10% of babies with EOGBS die Early-onset GBS infection (EOGBS) • Abnormally high or low temperature • Abnormally high or low heart rates • Abnormally high or low breathing rates Charity No. 1112065 Company Reg No 5587535
Types of GBS infection (2) • Develops 6 days - 3 months • Usually meningitis with septicaemia • Typical symptoms of late-onset GBS infection • Fever • Poor feeding and/or vomiting • Impaired consciousness • Plus any symptoms of meningitis • Even with the best medical care • 5% of babies sick with LOGBS die • up to 50% of survivors of GBS meningitis suffer long term handicaps Late-onset GBS infection (LOGBS) Charity No. 1112065 Company Reg No 5587535
GBS infections have a relatively high incidence of recurrence (1-3%) Consider low dose oral penicillin daily for 3 months Baby successfully treated for GBS infection Charity No. 1112065 Company Reg No 5587535
The Future • Rapid Near Patient Testing • Better than testing at 35-37 weeks in informing which women are carrying GBS in labour • Unfortunately, no tests currently both fast and accurate enough • More costly than enriched culture medium testing • Vaccine • Best approach for preventing both EOGBS and LOGBS infection, plus maternal GBS infection and other adult GBS infection • Target would be pregnant women or women before they become pregnant • Vaccine needs to be multivalent • Research is urgently needed into developing a viable vaccine for group B Strep infection • Decades away – big concerns re medico-legal issues Charity No. 1112065 Company Reg No 5587535
Key References • Centers for Disease Control & Prevention. Prevention of Perinatal Group B Streptococcal Disease: Revised Guidelines from CDC. MMWR Reports & Recommendations Vol. 51(No. RR 11) 16 August 2002. • Heath PT, Balfour G, Weisner AM, Efstratiou A, Lamagni TL, Tighe H, O'Connell LAF, Cafferkey M, Verlander NQ, Nicoll A & McCartney AC on behalf of the PHLS GBS Working Group. Group B streptococcal disease in UK and Irish Infants <90 days of age. Lancet 2004 Jan 24, Vol 363(9405):292. • Luck S, Torny M, d'Agapeyeff K, Pitt A, Heath P, Breathnach A & Bedford Russell A. Estimated early-onset group B streptococcal neonatal disease. Lancet, 2003 Jun 07; 361(9373): 1953-1954 • PHLS Communicable Disease Surveillance Unit. Incidence of group B streptococcal disease in infants aged less than 90 days. CDR weekly Vol. 12(No 16):3. 18 April 2002. • Colbourn TE, Asseburg C, Bojke L, Philips Z, Welton NJ, Claxton K, Ades AE, and Gilbert RE. Preventive strategies for group B streptococcal and other bacterial infections in early infancy: cost effectiveness and value of information analyses. BMJ 2007 335: 655 • Royal College of Obstetricians & Gynaecologists Clinical Green Top Guideline. Prevention of Early Onset Neonatal Group B Streptococcal Disease (36) – Nov 2003 • Law MR, Palomaki G, Alfirevic Z, Gilbert G, Heath P, McCartney C, Reid T, Schrag S on behalf of the Medical Screening Society Working Group on GBS disease. The prevention of neonatal group B streptococcal disease. J Med Screen 2005;12:60-68. • Yancey MK, Schuchat A, Brown LK, Ventura VL, Markenson GR. The accuracy of late antenatal screening cultures in predicting genital GBS colonization at delivery. Obstet Gynecol Nov 1996; 88(5):811-5. Charity No. 1112065 Company Reg No 5587535
Group B Strep Support • To inform health professionals and individuals how most EOGBS infection can be prevented; and • To offer information and support to families affected by GBS; • To generate continued support for research into preventing GBS infections. Registered charity set up in 1996 Aims: Funded by donations Charity No. 1112065 Company Reg No 5587535
LEAFLETS GBS & pregnancy(introduction for pregnant women) Congratulations on the safe arrival of your baby(introduction for parents of a healthy baby) Understanding your baby’s GBS infection(introduction for parents of a GBS baby) For women who carry GBS (detailed leaflet for women who know they carry GBS) If your baby was infected by GBS(detailed leaflet for parents of babies affected by GBS) GBS: The Facts (detailed leaflet, including medical reference list) POSTERS Pregnant?(for pregnant women) Labour & Delivery Prevention Guidelines Understanding your baby’s GBS infection– for SCBUs Saving Babies’ Lives – A2 STICKERS GBS Alert - 35 per page for pregnant women’s notes I am GBS Aware - 35 per page for pregnant women’s notes GBSS Materials Available Charity No. 1112065 Company Reg No 5587535
GBSS Medical Advisory Panel • Professor Philip Steer, BSc, MD, FRCOG (Chair) Emeritus professor at Imperial College and consultant obstetrician at the Chelsea and Westminster Hospital in London • Dr Alison Bedford-Russell MRCP Consultant Neonatologist, Birmingham Heartlands Hospital • Dr A Christine McCartney OBE FRCPath Director, Regional Microbiology Network, Health Protection Agency Central Office Charity No. 1112065 Company Reg No 5587535
What it’s all about …. ……. healthy babies Charity No. 1112065 Company Reg No 5587535