Antibody Responses to Hepatitis A Virus Vaccine in HIV‐Infected Children with Evidence of Immunologic Reconstitution while Receiving Highly Active Antiretroviral Therapy

Abstract

HIV-infected children with CD4+ T cell percentages > or = 20% responded better to the HAV vaccine if they had undetectable HIV RNA. The standard 2-dose immunization regimen generated low antibody titers with limited persistence. A third vaccine dose was safe and increased the antibody titers, suggesting that an increase in immunizations may be warranted in this population.

Shedding of live vaccine virus, comparative safety, and influenza-specific antibody responses after administration of live attenuated and inactivated trivalent influenza vaccines to HIV-infected children

“…Although within the immunologic Groups studied the lymphocyte phenotype and number were not associated with response to vaccination, HIV RNA plasma level was negatively correlated with serum HAI responses. An independent effect of HIV in plasma on immune response has been reported previously with both live and inactivated vaccines administered to HIV-infected children (38,39,44).…”

Determinants of Hepatitis A Vaccine Immunity in a Cohort of Human Immunodeficiency Virus-Infected Children Living in Switzerland

“…Thus, their physiologically higher lymphocyte and CD4 ϩ T cell counts were quite unlikely to have influenced our results. The role of CD4 ϩ T cells has already been demonstrated in several adult (16,21,24,35,39) and pediatric (25,28,30,37) pediatric population, and Overton et al, in an adult population, identified the viral load as a determinant of response to vaccination (22,37). Over 50% of the population in the study by Weinberg et al had a detectable viral load (cutoff, 400 HIV RNA copies/ ml) (37), while 73% of our HAV-seronegative population had an undetectable viral load (cutoff, 40 HIV RNA copies/ml).…”

“…ϩ T cell counts below 750 cells/l had anti-HAV antibody concentrations above 250 mIU/ml, a concentration which is virtually always exceeded in healthy persons (37).…”

“…In a population of pediatric patients (median age of 5.5 years) without severe symptoms or immunosuppression (all with T cell levels of Ͼ15%), Gouvea et al showed a 100% seroconversion rate (11). Otherwise, due to heterogeneity of study populations (27), results can differ, with seroconversion rates following HAV vaccination ranging from 48.5 to 94% in HIV-infected adults (16,21,22,24,33,35,39) and from 84.5 to 100% in HIVinfected children (11,25,28,30,37).…”

“…Studies with HIV-infected children are scarce and heterogeneous. Nevertheless, available data suggest a much better immune response than in adults (11,28,30,37). We present here the results of a prospective study with HIV-infected children enrolled in the Swiss Mother and Child HIV Cohort (MoCHiV) cohort.…”