The edition · Infectious Diseases
Shorter TB prevention for children: better completion, and fewer cases with 4HR
A network meta-analysis favours rifamycin-based short courses over nine months of isoniazid; asymptomatic mpox looks uncommon, and one in six pregnant women in Asia-Pacific carry group B strep.
The edition in brief
A network meta-analysis of 11 randomised trials in children and adolescents with TB infection found that four months of isoniazid and rifampicin (4HR) halved active TB compared with nine months of isoniazid (RR 0.49, 95% CI 0.32–0.76). Short courses — 3HP, 4HR and 4R — all had higher completion, and 4R had fewer adverse reactions than 9H, while 3HP had more than 4HR or 4R. The certainty is limited by a sparse, partly disconnected network. A meta-analysis of studies from 2022 to 2024 put asymptomatic mpox detection at about 1% in non-endemic regions, though with a wide prediction interval and no data on whether such people transmit. Across 98 studies and nearly one million pregnant women in the Asia-Pacific region, group B streptococcus colonisation was 18%, serotype III was commonest, and beta-lactam resistance was 0–2%, so penicillin remains reliable for intrapartum prophylaxis. The FDA lists a Class II recall of Baxter's premixed vancomycin in dextrose bags for manufacturing-practice deviations. The pearl is the step that must precede any TB preventive therapy: excluding active disease.
Asymptomatic mpox: about 1% detection across non-endemic studies
Reserve mpox testing for people with symptoms or lesions, and monitor exposed contacts rather than screening them.
Group B strep colonises 18% of pregnant women in Asia-Pacific; beta-lactams still work
Keep penicillin or ampicillin as the intrapartum GBS prophylaxis of choice; beta-lactam resistance remains rare.
FDA lists Class II recall of Baxter's premixed vancomycin in dextrose
Hospitals using premixed vancomycin bags should check stock against the recall and substitute pharmacy-prepared infusions if affected.
Exclude active TB before starting preventive treatment
Always rule out active TB before starting a child on preventive therapy.
TB preventive therapy in children: 4 months of isoniazid–rifampicin halved active TB against 9H
For children with TB infection, consider a short rifamycin-based regimen in preference to nine months of isoniazid, in line with national guidance.
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