An evaluation of infant immunization in Africa: is a transformation in progress?

OBJECTIVE: To assess the progress made towards meeting the goals of the African Regional Strategic Plan of the Expanded Programme on Immunization between 2001 and 2005. METHODS: We reviewed data from national infant immunization programmes in the 46 countries of WHOs African Region, reviewed the literature and analysed existing data sources. We carried out face-to-face and telephone interviews with relevant staff members at regional and subregional levels. FINDINGS: The African Region fell short of the target for 80% of countries to achieve at least 80% immunization coverage by 2005. However, diphtheria-tetanus-pertussis-3 coverage increased by 15%, from 54% in 2000 to 69% in 2004. As a result, we estimate that the number of nonimmunized children declined from 1.4 million in 2002 to 900,000 in 2004. In 2004, four of seven countries with endemic or re-established wild polio virus had coverage of 50% or less, and some neighbouring countries at high risk of importation did not meet the 80% vaccination target. Reported measles cases dropped from 520,000 in 2000 to 316,000 in 2005, and mortality was reduced by approximately 60% when compared to 1999 baseline levels. A network of measles and yellow fever laboratories had been established in 29 countries by July 2005. CONCLUSION: Rates of immunization coverage are improving dramatically in the WHO African Region. The huge increases in spending on immunization and the related improvements in programme performance are linked predominantly to increases in donor funding.     

Global control of hepatitis B virus: does treatment-induced antigenic change affect immunization?

Since its widespread introduction, the hepatitis B vaccine has become an essential part of infant immunization programmes globally. The vaccine has been particularly important for countries where the incidence of hepatitis B virus-related hepatocellular carcinoma is high. Effective treatment options for individuals with chronic hepatitis B infection were limited until 1998 when lamivudine, the first nucleoside analogue drug, was introduced. As a single treatment agent, however, lamivudine has a significant drawback: it induces lamivudine-resistant hepatitis B virus strains that may pose a risk to the global hepatitis B immunization programme. Mutations associated with drug treatment can cause changes to the surface antigen protein, the precise part of the virus that the hepatitis B vaccine mimics. However, the emergence of antiviral drug-associated potential vaccine escape mutants (ADAP-VEMs) in treated patients does not necessarily pose a significant, imminent threat to the global hepatitis B immunization programme. Nonetheless, there is already evidence that current treatment regimens have resulted in the selection of stable ADAP-VEMs. Treatment is currently intended to prevent the long-term complications of hepatitis B virus infection, with little consideration given to potential adverse public health impacts. To address individual and public health concerns, trials are urgently needed to find the optimal combination of existing drugs that are effective but do not induce the emergence of ADAP-VEMs. This paper examines the mechanism of antiviral drug-selected changes in the portion of the viral genome that also affects the surface antigen, and explores their potential impact on current hepatitis B immunization programmes.     

Maternal knowledge and infant uptake of valid hepatitis B vaccine birth dose at routine immunization clinics in Enugu State – Nigeria

BackgroundWorld Health Organization recommends hepatitis B vaccine birth dose for all infants within 24 hours of birth as the most cost-effective measure to prevent perinatal hepatitis B virus infection (HBV). We assessed and identified the predictors of maternal knowledge and infants’ uptake of valid hepatitis B vaccine birth dose (HepB-BD).MethodsWe conducted a hospital-based cross-sectional survey among 366 mother-infant attendees of routine immunization clinics selected by multi-stage sampling technique in Enugu State, Nigeria. We collected data on socio-demographic characteristics, delivery history, maternal knowledge and infant’s receipt of valid HepB-BD with interviewer-administered questionnaire. Maternal knowledge was assessed using nine domain questions. Overall, good knowledge was defined as a score of ≥50%. Only infants who received first hepatitis B dose within 24 hours were considered to have received valid BD. We calculated frequencies, performed Chi square test and logistic regression.ResultsOne hundred and two (29.7%) mothers knew HBV can be transmitted from mother to child; 119 (34.6%) and 156 (45.3%) knew their infant should receive valid HepB-BD and four doses for full immunization of HepB respectively. Overall, 114 (31.1%) mothers had good knowledge of HBV and 88 (26.9%) of 327 who delivered at the health facilities had valid HepB-BD. Predictors of maternal knowledge were attainment of tertiary education (adjusted Odds Ratio (aOR): 2.1, 95%CI: 1.3–3.5) and living in rural areas (aOR: 0.5, 95%CI: 0.3–0.9). Predictors of valid HepB-BD uptake were maternal knowledge (aOR: 2.4, 95%CI: 1.4–4.0) and delivery at facilities offering routine immunization services (aOR: 5.4, 95%CI: 2.5–11.9).ConclusionKnowledge and uptake of valid HepB-BD were low. Health education on benefits of valid HepB-BD was given to mothers after administration of questionnaires. We disseminated findings to the State Ministry of Health and recommended integration of child delivery and immunization services for birth dose vaccines especially valid HepB-BD.     

A mental health brief intervention in primary care: does it work?

An onsite adjunctive service appears to improve the care of patients with mental health disorders.     

Can monovalent hepatitis A and B vaccines be replaced by a combined hepatitis A/B vaccine during the primary immunization course?

A combined hepatitis A/B vaccine (Twinrix Adult) has been licensed in Germany since 1997. We investigated possible differences in immunogenicity and safety when changing over from vaccinations with monovalent vaccines made by different manufacturers to vaccinations with the combined hepatitis A/B vaccine in an open, randomized, multicenter trial. We therefore compared four different schemes changing over from concomitant vaccinations with monovalent vaccines against hepatitis A and B (Havrix 1440+Engerix-B or Vaqta+Gen H-B-Vax) to combined vaccination against hepatitis A+B with three injections of the combined hepatitis A/B vaccine (0, 1, and 6 month schedule). Local and general symptoms were mostly mild in all five groups. With complete three-dose course using the combined vaccine or an early changeover from monovalent vaccines to the combined vaccine, higher overall anti-HBs seroprotection rates and geometric mean concentrations (GMCs) against hepatitis B could be achieved as early as after 2 months as compared to those groups switching later to the combined vaccine. This study demonstrated for the first time that switching from monovalent hepatitis A and B vaccinations to the combined hepatitis A and B vaccination has no negative influence on the tolerability and improves the immunogenicity.     

Does standing at work during pregnancy result in reduced infant birth weight?

The purpose of this study was to investigate the association between infant birth weight and standing at work during pregnancy. A total of 1222 pregnant women employed in a large petrochemical corporation in Beijing, China, were enrolled in the study, after receiving permission from the government to have a child. The subjects were followed up from that time through their entire pregnancy, for a total of up to 12 months. All subjects delivered at the company staff hospital between 1996 and 1998. Various work-related physical activities during pregnancy were assessed using a structured questionnaire, and generalized additive models (GAMs) were performed to examine their association with birth weight. Of the assessed activities, only standing was significantly associated with birth weight. After adjusting for potential confounders, maternal standing hours per day at work was found to be significantly associated with reduced birth weight (-17.7 g, P = 0.03).     

A non-randomized vaccine effectiveness trial of accelerated infant hepatitis B immunization schedules with a first dose at birth or age 6 weeks in Côte d'Ivoire

Most African countries do not initiate hepatitis B vaccination at birth. We conducted a non-randomized controlled trial comparing hepatitis B vaccination given at age 0, 6, and 14 weeks versus the current Côte d’Ivoire schedule of 6, 10, and 14 weeks. Pregnant women were enrolled at four health centers in Abidjan. At age 9 months, 0.5% of infants in both the birth and 6-week cohorts were positive for HBsAg and all were born to HBeAg-positive women. Among infants of HBeAg-positive mothers, 9 of 24 (37.5%) in the birth cohort and 10 of 17 (58.8%) in the 6-week cohort were HBsAg positive (adjusted OR, 2.7; 95% CI: 0.7–11.0). While both vaccine schedules prevented most cases of infant HBV transmission, both also had high failure rates among infants of HBeAg-positive mothers. African infants may benefit from a birth dose but additional studies are needed to verify this hypothesis.     

What's happening to soul food? Regional and income differences in the African American diet

When African American diets are described in the literature, they usually reflect traditional Southern diets. This study uses food consumption data from the USDA 1994–96 Continuing Survey of Food Intakes by Individuals (CSFII) to examine the African American diet Foods consumed more frequently at breakfast, lunch and dinner were found to differ by region and income. These findings indicate that dietary guidance must consider evolving economic, social, cultural, environmental, and even ethnic changes within the African American community.     

Vaccination against hepatitis A during outbreaks starting in schools: what can we learn from experiences in central Italy?

Two outbreaks of hepatitis A started almost simultaneously in a maternal school and in a day care centre located at opposite sides of Florence, Italy, at the end of 2002. Both of them originated from immigrant children, and in both cases, hepatitis A was initially not recognised due to aspecific symptoms. While vaccination of contacts started with delay in the first outbreak, the same intervention was organised and performed in 3 days in the other. The outbreak starting in the maternal school caused 30 notified cases, plus 7 cases diagnosed retrospectively. Nine of them were in a secondary school, where vaccination (in accordance with the Italian national guidelines on hepatitis A (HA) vaccination) had been started only after a secondary case occurred. Only three cases occurred overall in the other outbreak starting in the day care centre, where >80% of infants, children and personnel were immunised. Although few asymptomatic infections probably occurred, no source of contagion existed any longer 2 months after immunisation. A rapid vaccination of school and family contacts of hepatitis A cases after the first case (irrespective of school grade) seems to play an important role to shorten outbreak duration.