Mortality among HIV-1- and human herpesvirus type 8-affected mother-infant pairs in Zambia.

OBJECTIVE: To determine the respective trends in mortality of Zambian mother-infant pairs based on maternal infection with HIV-1 and human herpesvirus type 8 (HHV-8). METHODS: A prospective cohort study was done on Zambian mother-infant pairs, stratified by maternal serologic status and followed from 6 weeks postdelivery for 48 months. Statistical analysis of the differences in the calculated mortality rates among the four groups was done using Stata 7.0. Kaplan-Meier analysis and Cox proportional hazard models were used to measure subject survival time. RESULTS: Between September 1998 and March 2002, a total of 1,425 mother-infant pairs were enrolled. The crude mortality rate among children born to dually infected mothers was approximately 9 times higher (245.90 deaths per 1,000 live births) when compared with the death ratio of children born to seronegative mothers (24.63 deaths per 1,000 live births). The incidence rate for death was 0.34/1,000 in infants of co-infected mothers in comparison with 0.32/1,000 among HIV-1-infected mothers, 0.0336/1,000 among uninfected mothers, and 0.0403/1,000 among HHV-8-infected mothers (chi(2) = 154.56; P < 0.01). Infants of co-infected mothers had a comparable risk of death in comparison with infants infected with HIV-1 alone [hazard ratio, 9.91 [95% confidence interval (95% CI), 5.08-19.37] for co-infected versus 9.26 [95% CI, 4.75-18.07] for HIV-1-infected alone]. Infants of mothers infected only with HHV-8 also had comparable survival in comparison with uninfected infants (hazard ratio, 1.21; 95% CI, 0.56-2.61). CONCLUSION: Infants born to mothers dually infected with both HIV-1 and HHV-8 have comparable survival with infants exposed to HIV-1 alone. Infants born to mothers infected only with HHV-8 have comparable survival with uninfected infants.

Development of an immunofluorescence assay using recombinant proteins expressed in insect cells to screen and confirm presence of human herpesvirus 8-specific antibodies.

Human herpesvirus 8 (HHV-8), or Kaposi's sarcoma (KS)-associated herpesvirus, has been linked to all forms of KS. The results of most current serological assays for the detection of HHV-8-specific antibodies have low levels of concordance among themselves. To establish a sensitive and specific testing strategy that can be used to screen for HHV-8-specific antibodies, three HHV-8 proteins, ORF65, ORF73, and K8.1A, were expressed by using baculoviral vectors in insect cells and incorporated into a monoclonal antibody-enhanced immunofluorescence assay (mIFA) termed the Sf9 three-antigen mIFA. The results obtained by this mIFA were compared to those obtained by a standard mIFA with an HHV-8-infected B-cell line (BC3 mIFA). Test sera were obtained from patients diagnosed with KS, human immunodeficiency virus type 1-infected patients at high risk for HHV-8 infection, and healthy controls from a local blood bank. The combined use of both assays had a sensitivity of 94% and a specificity of 96%. The performance of these two assays when they were used together indicates that they may be useful for the reliable detection of HHV-8-specific immunoglobulin G antibodies in a population.

Postnatal human herpesvirus 8 and human immunodeficiency virus type 1 infection in mothers and infants from Zambia.

The specific route and timing of human herpesvirus (HHV) 8 infection in regions where Kaposi sarcoma is endemic are not known. HHV-8 infection and any risk factors that may be associated with HHV-8, including human immunodeficiency virus (HIV) type 1 infection, were monitored during the 12-month postdelivery period for 416 mothers and 485 infants from Lusaka, Zambia. HHV-8 incident infection rates during this period were 3.2 and 5.3 infections/100 person-years for infants and mothers, respectively. HHV-8 infection among infants was not associated with HHV-8 or HIV-1 infection in the mother. Among the HHV-8-positive infants, 2 of 12 tested were found to have HHV-8 DNA in their peripheral blood mononuclear cells at birth, which suggests that in utero infection is possible. However, most HHV-8-positive infants appeared to have acquired infection either intrapartum or postpartum. The present study indicates that transmission of HHV-8 to infants can occur early and is likely via multiple routes.