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Background: In clinical trials, maternal tetanus toxoid (TT) vaccination is effective in protecting newborns against tetanus infection, but inadequate placental transfer of tetanus antibodies may contribute to lower-than-expected rates of protection in routine practice. We studied the effect of placental malaria and maternal human immunodeficiency virus (HIV) infection on placental transfer of antibodies to tetanus., Methods: A total of 704 maternal-cord paired serum samples were tested by ELISA for antibodies to tetanus. The HIV status of all women was determined by an immunoglobulin G antibody-capture particle-adherence test, and placental malaria was determined by placental biopsy. Maternal history of TT vaccination was recorded., Results: Tetanus antibody levels were reduced by 52% (95% confidence interval [CI], 30%-67%) in newborns of HIV-infected women and by 48% (95% CI, 26%-62%) in newborns whose mothers had active-chronic or past placental malaria. Thirty-seven mothers (5.3%) and 55 newborns (7.8%) had tetanus antibody levels <0.1 IU/mL (i.e., were seronegative). Mothers' self-reported history of lack of tetanus immunization was the strongest predictor of seronegativity and of tetanus antibody levels in maternal and cord serum., Conclusion: Malarial and HIV infections may hinder efforts to eliminate maternal and neonatal tetanus, making implementation of the current policy for mass vaccination of women of childbearing age an urgent priority.

Introduction: Young infants are protected from measles infection by maternal measles antibodies. The level of these antibodies at birth depends on the level of antibodies in the mother and the extent of placental transfer. We investigated predictors of levels of measles antibodies in newborns in rural Kenya., Methods: A total of 747 paired maternal-cord serum samples (91 from human immunodeficiency virus [HIV]-infected and 656 from HIV-uninfected mothers) were tested for measles immunoglobulin G antibodies. Placental malaria infection was determined by biopsy. Data on pregnancy history, gestational age, and anthropometric and socioeconomic status were collected., Results: Infants born to HIV-infected mothers were more likely (odds ratio, 4.6 [95% confidence interval {CI}, 2.2-9.7]) to be seronegative and had 35.1% (95% CI, 9.8%-53.2%) lower levels of measles antibodies than did those born to HIV-uninfected mothers. Preterm delivery, early maternal age, and ethnic group were also associated with reduced levels of measles antibodies. There was little evidence that placental malaria infection was associated with levels of measles antibodies in newborns., Conclusion: Our results suggest that maternal HIV infection may reduce levels of measles antibodies in newborns. Low levels of measles antibodies at birth render children susceptible to measles infection at an early age. This is of concern in sub-Saharan African countries, where not only is the prevalence of HIV high, but measles is the cause of much morbidity and mortality.

Objectives: To determine morbidity and mortality from measles and to estimate measles vaccine effectiveness among children hospitalised with measles in two hospitals in Nairobi., Design: A review of hospital records (index cards)., Setting: Kenyatta National Hospital and Mbagathi District Hospitals covering the years 1996-2000., Method: A review of index cards for measles morbility and mortality was undertaken in the two hospitals. Measles data at the Kenya Expanded Programme on Immunisation covering both hospitals was analysed for vaccine effectiveness., Results: The incidence of measles was unusually high in 1998 between July and November (monthly range 130-305), reflecting on the occurrence of an outbreak at that time. There was no definite monthly incidence trend of measles in 1996,1997, 1999 and 2000. The median age of cases was 13 months (range 0-420 months) for Kenyatta hospital and 18 months (range 1-336 months) for Mbagathi Hospital. Significantly, 29.8% of all cases were aged below nine months when routine immunisation for measles had not begun. The median number of days spent in hospital were five days (range 0-87 days) for Kenyatta and four days (range 1-13 days) for Mbagathi. The overall case fatality rate was 5.6% and was similar for both males and females. The overall measles vaccine effectiveness among measles cases admitted to Kenyatta and Mbagathi Hospitals was 84.1%., Conclusion: The case admissions in Kenyatta and Mbagathi Hospitals suggest measles was prevalent in Nairobi over the latter half decade of the 1990's. Apart from 1998 when there was an outbreak, the seasonality of measles was dampened. The 1998 outbreak suggests a build up of susceptible children the majority of whom were born in the last quarter of 1996. The high mortality may have had to do with the majority of cases presenting late when symptoms were already complicated and severe.