Whole-Cell Pertussis Vaccine Induces Low Antibody Levels in Human Immunodeficiency Virus-Infected Children Living in Sub-Saharan Africa

Abstract

The WHO recommendations for the immunization of children infected with human immunodeficiency virus (HIV) differ slightly from the guidelines for uninfected children. The introduction of antiretroviral therapy for HIV-infected infants should considerably prolong their life expectancy. The question of the response to the whole-cell pertussis (wP) vaccine should now be addressed, particularly in countries in which pertussis remains endemic. To evaluate the persistence of antibodies to the wP vaccine in HIV-infected and uninfected children who had previously received this vaccine in routine clinical practice, we conducted a cross-sectional study of children aged 18 to 36 months, born to HIV-infected mothers and living in Cameroon or the Central African Republic. We tested blood samples for antibodies to the wP vaccine and for antibodies to diphtheria and tetanus toxoids (D and T, respectively) in the context of the use of a combined DTwP vaccine. We enrolled 50 HIV-infected children and 78 uninfected, HIV-exposed children in the study. A lower proportion of HIV-infected children than uninfected children had antibodies against the antigens tested for all valences of the DTwP vaccine. Agglutinin levels were substantially lower in HIV-infected than in HIV-exposed but uninfected children (30.0% versus 55.1%, respectively; P ‫؍‬ 0.005). We also observed a high risk of low antibody levels in response to the DTwP vaccine in HIV-infected children with severe immunodeficiency (CD4 T-cell level, <25%). The concentrations of antibodies induced by the DTwP vaccine were lower in HIV-infected children than in uninfected children. This study supports the need for a booster dose of the DTwP vaccine in order to maintain high antibody levels in HIV-infected children.

Incidence and Diagnosis of Pertussis in South African Children Hospitalized With Lower Respiratory Tract Infection

“…24 The observed increase in pertussis cases in these groups may relate to both reduced vaccine effectiveness and passive immunity associated with HIV infection or exposure. [25][26][27][28] Consistent with other studies, the risk of B. pertussis was higher in younger infants and decreased with each extra dose of vaccine received, with the lowest risk after a completed primary schedule. 18 A novel, important finding was the higher sensitivity for diagnosis of Bordetella spp.…”

Risk factors for Bordetella pertussis disease in hospitalized children

“…Risk factors for pertussis include lack of immunization or impaired immune responses to vaccination. Laboratory studies suggest that immune responsiveness to pertussis vaccines may be impaired by both infection and intrauterine exposure to HIV even in HIV-uninfected children [8][9][10][11]. Another factor associated with reduced immune responses to pertussis vaccine is poor nutritional status, a common problem among children in low and middle-income countries (LMIC) [12].…”

Impaired Humoral Response to Vaccines among HIV-Exposed Uninfected Infants

“…Studies concerning the efficacy of the vaccines in HIV-exposed infants have focused on children who become infected (1,16,26,30,34,35). There is a paucity of studies investigating the HIV-exposed uninfected (HEU) infant responses to vaccines (15,18,29).…”