Experimental Pneumococcal Carriage in People Living With HIV

The goal of this experimental pneumococcal carriage study is to to characterise rates and determinants of experimental pneumococcal carriage in PLHIV.The main questions it aims to answer are:can PLHIV be experimentally inoculated with pneumococcus in a safe manner?what are the immunological determinants of pneumococcal carriage in PLHIV compared to HIV-negative participants?how do the pneumococcal carriage dynamics differ between PLHIV and HIV-negative participants?Participants will be inoculated intranasally with a controlled concentration of pneumococcus after which they will be monitored for 21 days during which nasal and systemic immune dynamics and pneumococcal carriage dynamics will be evaluated. At the end of the study any participants exhibiting carriage will have the pneumococcus cleared with antibiotics.

Inclusion Criteria:Aged 25 to 45 years oldFluent spoken and written Chichewa or EnglishAble to give informed written consentAccess to a functional mobile phoneEstablish on antiretroviral therapy for ≥2 years (if PLHIV)Viral load below the lower limit of detection (<LDL) at screening (if PLHIV)CD4 count over 350 cells/mm³ at screening (if PLHIV)Exclusion Criteria:HIV-associated hospitalisation and/or treatment for major illness in preceding 2 yearsCurrently under investigation for HIV-associated weight-loss, chronic diarrhoea, chronic cough, or another unexplained symptomPrevious illness caused by pneumococcusAdditional condition or medication impairing immune response or increasing risk of pneumococcal diseaseLiving in close contact with an individual vulnerable to pneumococcal diseaseAllergy to penicillinAcute illness in 7 days preceding inoculationAntibiotic course in last 2 weeks (excluding prophylactic co-trimoxazole in PLHIV)Pregnant or trying to conceiveInvolved in another clinical study (unless observational or in follow-up)Current regular cigarette smoking (5+ cigarettes per week)Natural carrier of pneumococcus serotype 6B at screening visitParticipants without a guardian