Group B Strep Support

The More You Know…It’s about informed choice

The amount of engagement on our Social Media pages, especially Facebook, surrounding the e-petition call to action hit an all-time high. We did notice though that there was a lot of misinformation being circulated regarding the principles at the heart of the petition…i.e the ‘pros and cons’ of testing and when antibiotics are to be offered. This misinformation led to some people not supporting the petition but more importantly it can lead to the kind of tragic outcomes we’re desperately trying to prevent.

The first ‘ask’ on the petition was that every woman be given accurate information about group B Strep. This is clearly not happening and begets lack of accurate information being given about testing. There are officially three different tests for GBS and it is crucial to know which is being offered. There is the Standard Direct Plating method which is the conventional NHS test, the ECM (Enriched Culture Medium method) recognised as the ‘gold standard’ for detecting GBS, and the Polymerase Chain Reaction method which is not widely available in the UK.

1.The conventional NHS test (Standard Direct Plating): This is the method generally used in the NHS when a swab is taken because of vaginal symptoms and the method is described in Public Health England’s UK SMI B281. It was not specifically designed to detect group B Strep and is not a sensitive test for this purpose. The UK SMI B28 says, “According to local protocol, patients judged at high risk for the development of group B streptococcal infection may be screened for carriage. Optimum yield will be achieved by selective/enrichment procedures applied to swabs obtained from the vagina and the anorectum.” Usually only a vaginal (and often a high vaginal) swab is taken and sent to the lab. The cells from the swab are then transferred onto a dish or ‘plate’ containing agar (a non-enriched growth medium) and after 24 and 48 hours incubation, the plate is examined to see if GBS has grown.

a.A positive result using this test method is highly reliable – there are few falsely positive results.

b.A negative result using this method is not very reliable – it gives a high proportion of falsely negative results. GBS will be isolated in only around 50% of cases where the Mum is carrying GBS as the swab was taken. This test is unselective – other bacteria present on the swab may outgrow and ‘swamp’ the GBS sample.

*Many health professionals and most pregnant women are unaware of just how high the false-negative rate is for these standard tests.

2.The ECM test (Enriched Culture Method): Designed specifically to detect group B Strep carriage, this ‘gold standard’ test is described by Public Health England’s UK SMI B582. It is available from a few NHS trusts and several private labs, some of which offer a home-testing service. This method requires samples taken from the low vagina and rectum (either one combined vaginal/rectal swab or two separate swabs processed as one) which are then sent off to the laboratory specifically marked “for GBS culture in ECM”. The cells from the swab(s) are incubated in an enriched culture medium specifically designed to encourage the growth of GBS and thus enhancing its detection. After incubation, the specimen is sub-cultured onto an agar plate. The bacteria have to grow into a sizeable colony before they can be identified, so getting a result usually takes a minimum of 24 hours, and more usually 48-72 hours to establish whether GBS has grown. Public Health England UK Standards for Microbiology Investigations B 58 states that not only are the standard tests inferior to the enrichment tests for detecting GBS carriage, “…the evidence accumulated has shown that the sensitivity and specificity of direct antigen tests is inferior to that of culture methods.” 3 Research4 has shown that, when the ECM test is properly performed within 5 weeks of delivery (35-37 weeks),

a.a positive result was 87% predictive of carrying GBS at delivery (13% of women lost carriage between performing the test and giving birth)

b. a negative result was 96% predictive of not carrying GBS at delivery (4% of women acquired carriage between the test and giving birth)

Remember, GBS carriage status can come and go over a period of time (though not day by day), hence the suggestion for testing within the 35-37 week window.

Testing then brings us to the topic of antibiotics in labour. If you choose to be tested or a test is done for you based for other reasons and the result is positive, then UK guidelines (5) state that intravenous antibiotics (IV) should be OFFERED to you as soon as possible from the start of labour and then at regular intervals until baby is born. Once again, it is your choice whether or not to have them.

1.According to both NICE and the RCOG(6) intravenous antibiotics should automatically be offered in the following circumstances:

a.If GBS has been found during your current pregnancy from a vaginal or rectal swab.

b.If group B Strep was found during your current pregnancy from a urine sample. (Women with GBS urinary tract infection during pregnancy should receive appropriate treatment at the time of diagnosis as well as IV antibiotics in labour.)

c.If a previous baby developed GBS infection.

d.If you have a fever in labour (temperature of greater than 38oC) and/or chorionamnionitis (a condition where bacteria infect the chorion and amnion (the membranes that surround the baby) and the amniotic fluid (in which the baby floats) which can lead to infections in both the mother and baby) is suspected, you should be offered broad-spectrum antibiotics which include GBS cover.

2.Simply carrying GBS before the current pregnancy, without a positive test result this pregnancy, does not mean you will automatically be offered intravenous antibiotics in labour unless other risk factors are also present. Different trusts may use different risk factors or combinations of risk factors, including

a.Labour starts or membranes rupture before 37 completed weeks of pregnancy (i.e. preterm),

b.where there is prolonged rupture of the membranes – more than 18 hours before delivery,

Not every pregnant Mum who has GBS detected during her pregnancy will want intravenous antibiotics in labour. Many will, but others may decide not to have them unless there are other additional risk factors – only a relatively small percentage of babies born to Mums carrying GBS at delivery will actually develop GBS infection. If you do decide against antibiotics in labour, it would be prudent for the baby to be observed by trained staff for at least 12 hours which brings us to our final point – the signs and symptoms of both early and late onset GBS infection.

Early-onset GBS infection is defined as that which presents within the first 6 days of life. In the UK, up to 75% of GBS infections are of early onset and are usually apparent within the first 12 hours of life. It usually presents as septicaemia with pneumonia. The signs to watch for include:

•Rapid breathing or stopping breathing.

•Making grunting sounds.

•Poor feeding.

•Being abnormally drowsy (lethargic).

•Being irritable.

•High/Low temperature.

•High/Low heart rate.

•Low blood pressure.

•Low blood sugar.

•Pale, blotchy skin

Late onset GBS infection presents between 7 days and three months of age. Up to 25% of GBS infections are late-onset, usually as meningitis with septicaemia. It is uncommon after a baby reaches one month old and very rare after age three months. These warning signs include:

•Being irritable with high pitched or whimpering cry, or moaning

•Blank, staring or trance-like expression

•Floppy, may dislike being handled, be fretful

•Tense of bulging fontanelle (soft spot on babies’ heads)

•Turns away from bright light.

•Involuntary stiff body or jerking movements

•Pale, blotchy skin

While we do post lots of information on testing and antibiotics in labour, the bottom line is that we at Group B Strep Support believe in informed choice. We want mums to be thoroughly educated about group B Strep so they can make the best decision for themselves and their babies regarding both testing and preventative treatment. We also do not advocate the unnecessary use of antibiotics…the ‘just in case’ approach. Our website has a wealth of information and frequently asked questions for parents to be, as well as professional guidelines, research papers, and free informative leaflets/posters for the medical professionals.

This last push of the e-petition proved very productive despite not reaching our 100,000 signature goal. It closed on Tuesday 10th February with just shy of 54,000 signatures, the most of any GBS petition to date which is something to celebrate. The media coverage raising awareness was astounding. Brave families like the Carrie & Jonathan Evans, Emma & Jason Cotton, Jo Beven and Jackie Watt all shared their heart-breaking group B Strep stories with newspapers, TV and radio. Doctors such Dr Gopal Rao OBE, Consultant Microbiologist at The North West London Hospitals NHS Trust and Dr Bryan Beattie of Innermost Healthcare also got involved in supporting the campaign.

We appreciate everyone’s support and online dialogues, even the more heated debates because it gave us an opportunity to provide more information and clarity!

Please don’t hesitate to contact us directly on Facebook or Twitter. Better yet, please email or call us with your questions and concerns! | 01444 416176



3 | Honest H, Sharma S,Khan KS. Rapid Test for Group B Streptococcus Colonization in Laboring Women: A Systematic Review. Pediatrics 2006; 117: 1055-66.