Adequate seroconversion should be confirmed. The development of effective broad-coverage meningococcal B vaccines continues to be challenging Cabozantinib because of the global diversity of meningococcal B strains coupled with cross-reactivity of the serogroup B capsular polysaccharide with human tissues: at the time of writing, progress towards licensed products in Europe is being made [45].

Vaccination against A, C, Y and W135 is indicated for HIV-positive children prior to travel to endemic regions, especially in association with Hajj pilgrimage to Saudi Arabia. Conjugate vaccines induce longer lasting T cell-dependent immunity at all ages, so quadrivalent conjugated meningitis A/C/Y/W135 vaccine is preferred over the polysaccharide preparations, although there are no published studies comparing the two in HIV-infected children. A multicentre study on the safety and immunogenicity of conjugate A/C/Y/W135 vaccine in HIV-positive 11- to 24-year-olds is this website currently under way [http://clinicaltrials.gov/ct2/show/NCT00459316 (accessed September 2011)]. The 7-valent pneumococcal conjugate vaccine (PCV7), which proved safe and immunogenic in HIV-positive infants and children [46, 47], has now been replaced by the 13-valent (PCV13) or 10-valent vaccine in many European

countries. These should also be immunogenic and safe in healthy and high-risk groups, but the outcomes of specific studies are awaited. HIV-positive children are at greatly increased risk of invasive pneumococcal disease,

Adenosine triphosphate even when on effective HAART; the risk is substantially reduced by immunization, especially using conjugate vaccines [46, 47]. World-wide, immunization recommendations accommodate this. The policy statement for use of PCV13 for HIV-infected children by the American Academy of Pediatrics in May 2010 [48] is broadly endorsed, although we advise against departure from a two-dose primary series to a three-dose course where individual countries’ routine schedules recommend the former. Guidance for transition from PCV7 to PCV13 is given [48] and if the two- or three-dose primary course plus booster dose does not include at least one dose of PCV13, a supplemental dose of PCV13 is advised. If the primary PCV course was given when the CD4 lymphocyte count was low for age (Table 1), revaccination should be considered following count recovery on HAART, especially if serotype-specific titres are low. Recommendations regarding the 23-valent pneumococcal polysaccharide vaccine (PPV23) are currently inconsistent. Different national advisory groups currently recommend different numbers of doses of PPV for high-risk groups.