Incidence of mother-to-child HIV transmission has declined to <0.5% among diagnosed HIV+ pregnant women delivering in the UK/Ireland (UK/I), however most children living with HIV in UK/I were born abroad. We describe evolving trends in the characteristics of children at diagnosis in the UK/I from 2000-15.
All children (<16y) diagnosed with HIV are reported to the National Study of HIV in Pregnancy and Childhood through an active surveillance system, including infants and children born in the UK/I to diagnosed and undiagnosed mothers, plus children born abroad arriving in the UK/I with unknown or known HIV status. HIV status is reconfirmed after arrival in the latter. Children receiving paediatric HIV care in UK/I are followed in the Collaborative HIV Paediatric Study (CHIPS). We report characteristics at time of UK/I diagnosis among those diagnosed in 2000-15.
Overall 1,528 children were diagnosed, annual numbers peaking at 150 during 2003-4 and stabilising at 30-50 per year since 2012 (p<0.001). 53% (804/1517) were female, 97% (1369/1408) reported as vertically infected and 65% (999/1528) born abroad (mainly sub-Saharan Africa), with this proportion increasing to 73% (109/150) from 2012. Among UK/I-born children born <2005, median age at diagnosis was 9mth (IQR 3mth-3y) vs 3mth (0.5y-1y) for those born ≥2010; among children born abroad median ages were 6yr (3-9y) vs 3yr (2-3y) respectively. The proportion of children with CDC C or B symptoms at UK/I diagnosis declined from 26% (132/509) and 34% (171/509) of those diagnosed in 2000-3, to 2% (3/150) and 11% (17/150) since 2012 respectively (p<0.001, for both trends). Of children born abroad 23% (228/999) were diagnosed before entering the UK/I, increasing over time (8% in 2000-3 to 55% ≥2012, p<0.001). By arrival 49% (112/228) were ART experienced [Figure], median age at ART start was 6y (IQR: 2y, 9y). Of 88/112 with known regimen, 76% initiated on a NNRTI and 14% a boosted-PI based regimen. Of patients linked in CHIPS with ART data after entry (73/88), 23% switched to a new regimen (change across drug/within PI class) within 1 year of arrival in UK/I.
Annual numbers of newly diagnosed children in the UK/I continue to decline, with increasing proportions of children born abroad and treatment experienced at arrival. Median age at diagnosis has decreased significantly, although remains higher for children born abroad. An encouraging trend is the declining proportion presenting with CDC B/C symptoms.