Uptake, Effectiveness and Acceptability of Routine Screening of Pregnant Migrants for Latent Tuberculosis Infection in Antenatal Care: a Feasibility Study

The UK has the second-highest TB incidence in Western Europe. Most active TB cases occur in the non-UK born population (migrants) in large cities such as London. Migrants most at risk of TB are from countries with a high TB incidence such as the Indian subcontinent and Sub-Saharan Africa. One quarter of the whole world population are estimated to have LTBI. Migrants who have acquired LTBI outside the UK, often reactivate in the first 5-10 years after arrival. Barts Health NHS trust has one of the highest number of TB notifications in England and manages 8% of active TB cases in the UK.

Many countries in SE Asia and Africa, which have the highest global TB burden, also have high maternal mortality rates. In women of reproductive age (15-45 years), TB is now among the three leading causes of death. In 2014, an estimated 480,000 women died as a result of TB globally. TB diagnosis in pregnancy is often delayed even in low-incidence countries. Pregnancy can mask the clinical manifestations of TB, as some of the symptoms of TB such as fatigue and loss of appetite are also common in pregnancy itself. There is a high risk of LTBI reactivation during pregnancy and postpartum likely due to T-cell suppression and reduced interferon-gamma production.There is an elevated risk of TB during pregnancy and immediately postpartum compared to the general population. TB in pregnancy carries a high risk of perinatal complications, poor foetal and maternal outcomes and early diagnosis of TB is important to prevent significant maternal and perinatal complications. A simple clinical algorithm recommended by the WHO based on absence of current cough, fever, weight loss, and night sweats can help to exclude active TB disease. Sputum smear has a low sensitivity for diagnosis of active TB in pregnancy, however health care professionals will have a higher index of suspicion for active TB in IGRA positive pregnant women presenting with symptoms suggestive of TB, thus preventing a delay in diagnosis. TB diagnosis in pregnancy can be delayed due to reduced awareness among health care providers and reluctance to investigate non-specific TB symptoms by chest radiography. Pregnant migrants may not be accessing routine health care and often do not have a GP. Antenatal care may therefore be a rare and critical opportunity to assess a woman's health and screen for TB. Moreover, antenatal care provides an opportunity for health promotion such as advocating GP registration. England's collaborative TB strategy recommends migrant screening for LTBI in high incidence areas in England including boroughs such as Newham. LTBI screening programmes have now been implemented. Between April 2015 and June 2016, 5,622 eligible migrants in England were offered an LTBI test, 2,904 (51%) of whom attended for the test. Newham was the first London borough to introduce a large-scale LTBI screening programme. A total of 20,905 LTBI tests were reported between July 2014 and June 2017 across England, nearly half of the tests were reported in Newham however uptake of screening remains low. This may be because individuals eligible for screening do not have symptoms and perceive the risk of developing active TB as low. Newham data has shown that uptake of screening varies significantly amongst GP surgeries indicating that uptake may be influenced by healthcare providers' knowledge and attitudes to screening but may also be due to other factors such as proximity to phlebotomy services. Data from the Clinical Effectiveness Group (CEG) at QMUL has shown that in pregnant migrant women screening uptake is even lower, <25% and this may be because pregnant women have not been told that LTBI screening is important. There is limited qualitative research about the acceptability to women of LTBI screening in pregnancy. Reasons for low uptake may be due to stigma of having active TB or fear of a positive test result affecting their immigration status. An opt-out approach normalises screening that otherwise may present barriers in relation to stigma.

Provider knowledge and understanding of the risks of TB screening and treatment is a major predictor of successful management of TB. Newham data has shown that offer of screening varies significantly amongst GP surgeries indicating that health care provider knowledge and attitude may influence offer of screening.

Evaluating the impact of healthcare provider training to improve TB management has mainly been performed in low income countries and there are only a few rigorous TB training evaluation studies available. E-learning modules use pre- and post- training tests to evaluate acquired knowledge. A GP E-learning module has been developed by TB Alert to enhance knowledge of GPs responsible for screening and treatment of LTBI but the effectiveness of the module has not been formally evaluated.

Aim of the feasibility study The investigator's aim is to assess whether it is feasible and acceptable to screen an at-risk migrant population for latent tuberculosis infection (LTBI) at routine antenatal booking visits in secondary care, using opt-out Interferon- gamma release assay (IGRA) testing. This will allow the investigators to develop a definitive large scale cluster randomised controlled trial (RCT) to evaluate the effectiveness of acceptable interventions to maximise migrant screening for LTBI in pregnancy, and to increase uptake of LTBI treatment postpartum.