| 1. |
- Aaby, Peter, et al.
(författare)
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Early diphtheria-tetanus-pertussis vaccination associated with higher female mortality and no difference in male mortality in a cohort of low birthweight children: an observational study within a randomised trial
- 2012
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Ingår i: Archives of Disease in Childhood. - : BMJ. - 0003-9888 .- 1468-2044. ; 97:8, s. 685-691
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Tidskriftsartikel (refereegranskat)abstract
- Background Studies from low-income countries have suggested that diphtheria-tetanus-pertussis (DTP) vaccine provided after Bacille Calmette-Guerin (BCG) vaccination may have a negative effect on female survival. The authors examined the effect of DTP in a cohort of low birthweight (LBW) infants. Methods 2320 LBW newborns were visited at 2, 6 and 12 months of age to assess nutritional and vaccination status. The authors examined survival until the 6-month visit for children who were DTP vaccinated and DTP unvaccinated at the 2-month visit. Results Two-thirds of the children had received DTP at 2 months and 50 deaths occurred between the 2-month and 6-month visits. DTP vaccinated children had a better anthropometric status for all indices than DTP unvaccinated children. Small mid-upper arm circumference (MUAC) was the strongest predictor of mortality. The death rate ratio (DRR) for DTP vaccinated versus DTP unvaccinated children differed significantly for girls (DRR 2.45; 95% CI 0.93 to 6.45) and boys (DRR 0.53; 95% CI 0.23 to 1.20) (p=0.018, homogeneity test). Adjusting for MUAC, the overall effect for DTP vaccinated children was 2.62 (95% CI 1.34 to 5.09); DRR was 5.68 (95% CI 1.83 to 17.7) for girls and 1.29 (95% CI 0.56 to 2.97) for boys (p=0.023, homogeneity test). While anthropometric indices were a strong predictor of mortality among boys, there was little or no association for girls. Conclusion Surprisingly, even though the children with the best nutritional status were vaccinated early, early DTP vaccination was associated with increased mortality for girls.
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| 2. |
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| 3. |
- Aaby, Peter, et al.
(författare)
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Randomized Trial of BCG Vaccination at Birth to Low-Birth-Weight Children: Beneficial Nonspecific Effects in the Neonatal Period?
- 2011
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Ingår i: Journal of Infectious Diseases. - : Oxford University Press (OUP). - 1537-6613 .- 0022-1899. ; 204:2, s. 245-252
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Tidskriftsartikel (refereegranskat)abstract
- Background. Observational studies have suggested that BCG may have nonspecific beneficial effects on survival. Low-birth-weight (LBW) children are not given BCG at birth in Guinea-Bissau; we conducted a randomized trial of BCG at birth (early BCG) vs delayed BCG. Methods. In the period 2004-2008 we recruited 2320 LBW children in Bissau. The children were visited at home at 2, 6, and 12 months of age. With a pretrial infant mortality of 250 per 1000, we hypothesized a 25% reduction in infant mortality for LBW children. Results. Infant mortality was only 101 per 1000 during the trial. In the primary analysis, infant mortality was reduced insignificantly by 17% (mortality rate ratio [MRR] = .83 [.63-1.08]). In secondary analyses, early BCG vaccine was safe with an MRR of .49 (.21-1.15) after 3 days and .55 (.34-.89) after 4 weeks. The reduction in neonatal mortality was mainly due to fewer cases of neonatal sepsis, respiratory infection, and fever. The impact of early BCG on infant mortality was marked for children weighing <1.5 kg (MRR = .43 [.21-.85]) who had lower coverage for diphtheria-tetanus-pertussis vaccinations. Conclusions. Though early BCG did not reduce infant mortality significantly, it may have a beneficial effect in the neonatal period. This could be important for public health because BCG is often delayed in low-income countries.
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| 4. |
- Benn, Christine Stabell, et al.
(författare)
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Vitamin A supplementation and BCG vaccination at birth in low birthweight neonates: two by two factorial randomised controlled trial
- 2010
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Ingår i: BMJ: British Medical Journal. - : BMJ. - 1756-1833. ; 340
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Tidskriftsartikel (refereegranskat)abstract
- Objective To investigate the effect of vitamin A supplementation and BCG vaccination at birth in low birthweight neonates. Design Randomised, placebo controlled, two by two factorial trial. Setting Bissau, Guinea-Bissau. Participants 1717 low birthweight neonates born at the national hospital. Intervention Neonates who weighed less than 2.5 kg were randomly assigned to 25 000 IU vitamin A or placebo, as well as to early BCG vaccine or the usual late BCG vaccine, and were followed until age 12 months. Main outcome measure Mortality, calculated as mortality rate ratios (MRRs), after follow-up to 12 months of age for infants who received vitamin A supplementation compared with those who received placebo. Results No interaction was observed between vitamin A supplementation and BCG vaccine allocation (P=0.73). Vitamin A supplementation at birth was not significantly associated with mortality: the MRR of vitamin A supplementation compared with placebo, controlled for randomisation to "early BCG" versus "no early BCG" was 1.08 (95% CI 0.79 to 1.47). Stratification by sex revealed a significant interaction between vitamin A supplementation and sex (P=0.046), the MRR of vitamin A supplementation being 0.74 ( 95% CI 0.45 to 1.22) in boys and 1.42 (95% CI 0.94 to 2.15) in girls. When these data were combined with data from a complementary trial among normal birthweight neonates in Guinea-Bissau, the combined estimate of the effect of neonatal vitamin A supplementation on mortality was 1.08 ( 95% CI 0.87 to 1.33); 0.80 ( 95% CI 0.58 to 1.10) in boys and 1.41 ( 95% CI 1.04 to 1.90) in girls (P=0.01 for interaction between neonatal vitamin A and sex). Conclusions The combined results of this trial and the complementary trial among normal birthweight neonates have now shown that, overall, it would not be beneficial to implement a neonatal vitamin A supplementation policy in Guinea-Bissau. Worryingly, the trials show that vitamin A supplementation at birth can be harmful in girls. Previous studies and future trials should investigate the possibility that vitamin A supplementation has sex differential effects.
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| 5. |
- Biering-Sorensen, Sofie, et al.
(författare)
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Small Randomized Trial Among Low-Birth-Weight Children Receiving Bacillus Calmette-Guerin Vaccination First Health Center Contact
- 2012
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Ingår i: Pediatric Infectious Disease Journal. - 1532-0987. ; 31:3, s. 306-308
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Tidskriftsartikel (refereegranskat)abstract
- A total of 105 low-birth-weight children presenting for first vaccination were randomized to receive bacillus Calmette-Guerin (BCG) immediately or later (current practice). The mortality rate ratio for BCG was 0.17 (95% CI = 0.02-1.35) within 3 days of enrollment, 0.28 (0.06-1.37) in the first month, and 0.27 (0.07-0.98) after 2 months of age. The mortality rate ratio was 0.41 (0.14-1.18) (P = 0.098) in infancy. Administration of BCG vaccine at first contact may contribute to lower mortality.
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| 6. |
- Diness, Birgitte R., et al.
(författare)
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Effect of high-dose vitamin A supplementation on the immune response to Bacille Calmette-Guerin vaccines
- 2007
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Ingår i: American Journal of Clinical Nutrition. - 1938-3207. ; 86:4, s. 1152-1159
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Tidskriftsartikel (refereegranskat)abstract
- Background: Vitamin A supplementation (VAS) at birth has been associated with decreased mortality in Asia. Bacille Calmette-Guerin (BCG) vaccine is given at birth in tuberculosis-endemic countries. Previous studies suggest that VAS may influence the immune response to vaccines. Objective: Our objective was to examine whether VAS influences the immune response to simultaneously administered BCG vaccine. Design: Within a randomized trial of 50 000 IU vitamin A or placebo Given with BCG vaccine at birth in Guinea-Bissau, 27 10 infants were examined for BCG scar formation and delayed-type hypersensitivity (DTH) to purified protein derivative of Mycobacterium tuberculosis (PPD) at 2 and 6 mo of age. The ex vivo cytokine response to PPD was measured in 607 infants. Results: At 2 mo of age, 39% (43% of the boys and 34% of the girls) responded to PPD. The prevalence ratio of a measurable PPD reaction for VAS compared with placebo recipients was 0.90 (95% CI: 0.80, 1.02) for all infants. 0.81 (95% CI: 0.69, 0.95) for boys, and 1.04 (95% CI: 0.86, 1.26) for girls. At 6 mo of age, 42% of the infants responded to PPD. No difference was observed between VAS and placebo recipients. The prevalence of BCG scar was not affected by VAS. The ex vivo interferon-gamma response to PPD was increased by VAS (means ratio: 1.40: 95% CI: 1.03, 1.91). Conclusions: VAS with BCG vaccination does not appear to interfere with the long-term immune response to BCG. However, VAS temporarily altered the DTH reaction to PPD in boys at 2 mo of age, suggesting sex differences in the immunologic response to VAS Given with BCG. This trial was registered at www.clinicaltrials.gov as #NCT00168597.
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| 7. |
- Rieckmann, Andreas, et al.
(författare)
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The Effect of Smallpox and Bacillus Calmette-Guérin Vaccination on the Risk of Human Immunodeficiency Virus-1 Infection in Guinea-Bissau and Denmark
- 2017
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Ingår i: Open Forum Infectious Diseases. - 2328-8957. ; 4:3
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Tidskriftsartikel (refereegranskat)abstract
- Background. The live smallpox and Bacillus Calmette-Guérin (BCG) vaccinations have been associated with better adult survival in both Guinea-Bissau and Denmark. In Guinea-Bissau, human immunodeficiency virus (HIV)-1 became an important cause of death after smallpox vaccination was phased out globally in 1980. We hypothesised that smallpox and BCG vaccinations were associated with a lower prevalence of HIV-1 infection, and we tested this hypothesis in both Guinea-Bissau and Denmark. Methods. We conducted 2 studies: (1) a cross-sectional study of HIV infection and vaccination scars in Guinea-Bissau including 1751 individuals and (2) a case-base study with a background population of 46 239 individuals in Denmark. In Guinea-Bissau, HIV-1 transmission was almost exclusively sexually transmitted. In Denmark, we excluded intravenous drug users. Data were analyzed using logistic regression. Results. Bacillus Calmette-Guérin and/or smallpox vaccination compared with neither of these vaccines was associated with an adjusted odds ratio (aOR) for HIV-1 of 0.62 (95% confidence interval [CI], 0.36-1.07) in Guinea-Bissau and 0.70 (95% CI, 0.43-1.15) in Denmark. We combined the results from both settings in a meta-analysis (aOR = 0.66; 95% CI, 0.46-0.96). Data from Guinea-Bissau indicated a stronger effect of multiple smallpox vaccination scars (aOR = 0.27; 95% CI, 0.10-0.75) as follows: women, aOR = 0.18 (95% CI, 0.05-0.64); men, aOR = 0.52 (95% CI, 0.12-2.33); sex-differential effect, P = .29. Conclusions. The studies from Guinea-Bissau and Denmark, 2 very different settings, both suggest that the BCG and smallpox vaccines could be associated with a decreased risk of sexually transmitted HIV-1. It might be informative to pursue this observation and explore possible protective mechanisms as part of the search for an HIV-1 vaccine.
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| 8. |
- Roth, Adam, et al.
(författare)
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Effect of revaccination with BCG in early childhood on mortality: randomised trial in Guinea-Bissau
- 2010
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Ingår i: BMJ: British Medical Journal. - : BMJ. - 1756-1833. ; 340
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Tidskriftsartikel (refereegranskat)abstract
- Objective To determine whether BCG revaccination at 19 months of age reduces overall child mortality. Design Randomised trial, with follow-up to age 5. Setting A health project in Bissau, Guinea-Bissau, which maintains a health and demographic surveillance system in an urban area with 90 000 inhabitants. Participants 2871 children aged 19 months to 5 years with low or no reactivity to tuberculin and who were not severely sick on the day of enrolment. Intervention BCG vaccination or no vaccination (control). Main outcome measure Hazard ratios for mortality. Results 77 children died during follow-up. Compared with controls, the BCG revaccinated children had a hazard ratio of 1.20 (95% confidence interval 0.77 to 1.89). Two hundred and fifty children were admitted to hospital for the first time between enrolment and the end of the study, with an incidence rate ratio for BCG revaccinated children versus controls of 1.04 (0.81 to 1.33). The trial was stopped prematurely because of a cluster of deaths in the BCG arm of the study. This increase in mortality occurred at a time when many children had received missing vaccinations or vitamin A or iron supplementation; the hazard ratio for BCG revaccinated children compared with controls was 2.69 (1.05 to 6.88) in the period after these campaigns. Throughout the trial, the effect of BCG revaccination on mortality was significantly different (P=0.006) in children who had received diphtheria-tetanus-pertussis (DTP) booster vaccination before enrolment (hazard ratio 0.36, 0.13 to 0.99) and children who had not received the booster before enrolment (1.78, 1.04 to 3.04). Conclusions There was no overall beneficial effect of being revaccinated with BCG. The effect of BCG revaccination on mortality might depend on other health interventions.
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| 9. |
- Sørup, Signe, et al.
(författare)
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Smallpox vaccination and all-cause infectious disease hospitalization: a Danish register-based cohort study.
- 2011
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Ingår i: International Journal of Epidemiology. - : Oxford University Press (OUP). - 1464-3685 .- 0300-5771. ; 40, s. 955-963
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: There is growing evidence from observational studies and randomized trials in low-income countries that vaccinations have non-specific effects. Administration of live vaccines reduces overall child morbidity and mortality, presumably due to protection against non-targeted infections. In Denmark, the live vaccine against smallpox was phased out in the 1970s due to the eradication of smallpox. We used the phasing-out period to investigate the effect of smallpox vaccination on the risk of hospitalization for infections. METHODS: From the Copenhagen School Health Records Register, a cohort of 4048 individuals was sampled, of whom 3559 had information about receiving or not receiving smallpox vaccination. Infectious disease hospitalizations were identified in the Danish National Patient Register. RESULTS: During 87 228 person-years of follow-up, 1440 infectious disease hospitalizations occurred. Smallpox-vaccinated individuals had a reduced risk of all-cause infectious disease hospitalization compared with smallpox-unvaccinated individuals [hazard ratio (HR) 0.84; 95% confidence interval (CI) 0.72-0.98]. The reduced risk of hospitalizations was seen for most subgroups of infectious diseases. The effect may have been most pronounced after early smallpox vaccination (vaccination age <3.5 years: HR 0.81; 95% CI 0.69-0.95; vaccination age ≥3.5 years: HR 0.91 95% CI 0.76-1.10). Among the smallpox-vaccinated, the risk of infectious disease hospitalization increased 6% with each 1-year increase in vaccination age (HR 1.06; 95% CI 1.02-1.10). CONCLUSION: Smallpox vaccination is associated with a reduced risk of infectious disease hospitalization in a high-income setting.
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| 10. |
- Villumsen, Marie, et al.
(författare)
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Risk of Inflammatory Bowel Disease following Bacille Calmette-Guérin and Smallpox Vaccination: A Population-based Danish Case-Cohort Study.
- 2013
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Ingår i: Inflammatory Bowel Diseases. - 1536-4844. ; 19:8, s. 1717-1724
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:: Childhood immunology has been suggested to play a role in development of inflammatory bowel disease (IBD) based on the studies of childhood vaccinations, infections, and treatment with antibiotics. Bacille Calmette-Guérin (BCG) and smallpox vaccinations were gradually phased-out in Denmark for children born between 1965 and 1976, hence allowing the study of subsequent risk of Crohn's disease and ulcerative colitis in a unique prospective design. METHODS:: The Copenhagen School Health Records Register contains detailed documentation of vaccination. Among the background cohort of individuals born between 1965 and 1976 (N = 47,622), cases with Crohn's disease (n = 218) and ulcerative colitis (n = 256) were identified through linkage to the Danish National Patient Registry. The vaccination status of the cases was compared with that of a subcohort (n = 5741) of the background cohort and analyzed in a case-cohort design. RESULTS:: No difference in risk of IBD was observed between individuals vaccinated and unvaccinated with BCG (hazard ratio = 0.95; 95% confidence interval, 0.75-1.19) or smallpox vaccine (hazard ratio = 1.01; 95% confidence interval, 0.77-1.32). This was also the case for Crohn's disease and ulcerative colitis separately. However, BCG given before 4 months of age may decrease the risk of IBD (hazard ratio = 0.43; 95% confidence interval, 0.20-0.93). CONCLUSIONS:: This prospective long-term case-cohort study shows that BCG and smallpox vaccination do not cause IBD later in life. These findings are important for the etiological understanding of IBD and of clinical importance because BCG is still one of the most commonly used childhood vaccinations, smallpox vaccine has been reintroduced in the U.S. military, and both vaccines may be used as vectors in new vaccines.
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