| 1. |
- Aaby, Peter, et al.
(author)
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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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In: Archives of Disease in Childhood. - : BMJ. - 0003-9888 .- 1468-2044. ; 97:8, s. 685-691
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Journal article (peer-reviewed)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.
(author)
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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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In: Journal of Infectious Diseases. - : Oxford University Press (OUP). - 1537-6613 .- 0022-1899. ; 204:2, s. 245-252
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Journal article (peer-reviewed)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. |
- Andersen, Andreas, et al.
(author)
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The immunological effect of revaccination with Bacille Calmette-Guerin vaccine at 19 months of age
- 2013
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In: Vaccine. - : Elsevier BV. - 1873-2518 .- 0264-410X. ; 31:17, s. 2137-2144
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Journal article (peer-reviewed)abstract
- Background: Bacille Calmette-Guerin (BCG) vaccination has important non-specific immune effects. In a randomized trial in Guinea-Bissau, BCG revaccination was associated with significantly increased survival in children who received diphtheria-tetanus-pertussis (DTP)-booster vaccine before enrolment and in children who did not receive micronutrient supplementation (MN). Within the trial we assessed the immunological effects of BCG revaccination. Methods: Children were randomized to BCG or nothing. Blood was sampled 6-11 weeks after randomization (early sample group) or 5-9 months later (late sample group). In vitro cytokine responses (interferon (IFN)-gamma, interleukin (IL)-13, tumor-necrosis-factor (TNF)-alpha, and IL-10) were assessed in whole blood cultures stimulated with lipopolysaccharide (LPS), purified protein derivative (PPD) or phytohaemagglutinin (PHA). Effect-modification by sex, DTP-booster vaccination and MN was studied. Results: Cytokines were measured in 345 infants. BCG was associated with significantly increased IFN-gamma (geometric mean ratio (GMR) = 4.54 (95% confidence interval: 3.13-6.58)) and IL-13 (GMR = 1.43 (1.00-2.05)) PPD responses, the effect being strongest in the early sample group. Across all three conditions BCG tended to increase IL-10 (LPS, PHA, PPD: GMR = 1.20, 1.12, 1.20), most pronounced in the late sample group. BCG reduced the TNF-alpha/IL-10 ratio in boys with DTP-booster at bleeding and increased it in those without (interaction test: p = 0.03). In children without MN, BCG was associated with reduced TNF-alpha response in the early sample group (p = 0.006), and increased IL-10 in the late sample group (p = 0.03). Conclusion: BCG revaccination resulted in a strong IFN-gamma response to PPD, which waned slightly over time. BCG also affected the pro-/anti-inflammatory balance, with reduced TNF-alpha and increased IL-10 responses to LPS, PHA and PPD. This effect depended on sex, DTP-booster vaccination and micronutrient supplementation, being most pronounced in children who had received DTP-booster before enrolment and children who had not received MN, i.e. the group of children which also had lower mortality after BCG revaccination. (C) 2013 Elsevier Ltd. All rights reserved.
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| 5. |
- Benn, Christine Stabell, et al.
(author)
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Effect of 50 000 IU vitamin A given with BCG vaccine on mortality in infants in Guinea-Bissau: randomised placebo controlled trial
- 2008
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In: BMJ (International Edition). - 0959-8146. ; 336:7658, s. 1416-1416
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Journal article (peer-reviewed)abstract
- Objective To investigate the effect of high dose vitamin A supplementation given with BCG vaccine at birth in an African setting with high infant mortality. Design Randomised placebo controlled trial. Setting Bandim Health Project's demographic surveillance system in Guinea-Bissau, covering approximately 90 000 inhabitants. Participants 4345 infants due to receive BCG. Intervention Infants were randomised to 50 000 IU vitamin A or placebo and followed until age 12 months. Main outcome measure Mortality rate ratios. Results 174 children died during follow-up (mortality=47/ 1000 person-years). Vitamin A supplementation was not significantly associated with mortality; the mortality rate ratio was 1.07 (95% confidence interval 0.79 to 1.44). The effect was 1.00 (0.65 to 1.56) during the first four months and 1.13 (0.75 to 1.68) from 4 to 12 months of age. The mortality rate ratio in boys was 0.84 (0.55 to 1.27) compared with 1.39 (0.90 to 2.14) in girls (P for interaction=0.10). An explorative analysis revealed a strong interaction between vitamin A and season of administration. Conclusions Vitamin A supplementation given with BCG vaccine at birth had no significant benefit in this African setting. Although little doubt exists that vitamin A supplementation reduces mortality in older children, a global recommendation of supplementation for all newborn infants may not contribute to better survival. Registration Clinical trials NCT00168597.
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| 6. |
- Benn, Christine Stabell, et al.
(author)
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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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In: BMJ: British Medical Journal. - : BMJ. - 1756-1833. ; 340
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Journal article (peer-reviewed)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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| 7. |
- Biering-Sorensen, Sofie, et al.
(author)
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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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In: Pediatric Infectious Disease Journal. - 1532-0987. ; 31:3, s. 306-308
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Journal article (peer-reviewed)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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| 8. |
- Diness, Birgitte R., et al.
(author)
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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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In: American Journal of Clinical Nutrition. - 1938-3207. ; 86:4, s. 1152-1159
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Journal article (peer-reviewed)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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| 9. |
- James, Katherine L., et al.
(author)
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Low-Bias RNA Sequencing of the HIV-2 Genome from Blood Plasma
- 2019
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In: Journal of Virology. - 1098-5514. ; 93:1
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Journal article (peer-reviewed)abstract
- Accurate determination of the genetic diversity present in the HIV quasispecies is critical for the development of a preventative vaccine: in particular, little is known about viral genetic diversity for the second type of HIV, HIV-2. A better understanding of HIV-2 biology is relevant to the HIV vaccine field because a substantial proportion of infected people experience long-term viral control, and prior HIV-2 infection has been associated with slower HIV-1 disease progression in coinfected subjects. The majority of traditional and next-generation sequencing methods have relied on target amplification prior to sequencing, introducing biases that may obscure the true signals of diversity in the viral population. Additionally, target enrichment through PCR requires a priori sequence knowledge, which is lacking for HIV-2. Therefore, a target enrichment free method of library preparation would be valuable for the field. We applied an RNA shotgun sequencing (RNA-Seq) method without PCR amplification to cultured viral stocks and patient plasma samples from HIV-2-infected individuals. Libraries generated from total plasma RNA were analyzed with a two-step pipeline: (i) de novo genome assembly, followed by (ii) read remapping. By this approach, whole-genome sequences were generated with a 28× to 67× mean depth of coverage. Assembled reads showed a low level of GC bias, and comparison of the genome diversities at the intrahost level showed low diversity in the accessory gene vpx in all patients. Our study demonstrates that RNA-Seq is a feasible full-genome de novo sequencing method for blood plasma samples collected from HIV-2-infected individuals.IMPORTANCE An accurate picture of viral genetic diversity is critical for the development of a globally effective HIV vaccine. However, sequencing strategies are often complicated by target enrichment prior to sequencing, introducing biases that can distort variant frequencies, which are not easily corrected for in downstream analyses. Additionally, detailed a priori sequence knowledge is needed to inform robust primer design when employing PCR amplification, a factor that is often lacking when working with tropical diseases localized in developing countries. Previous work has demonstrated that direct RNA shotgun sequencing (RNA-Seq) can be used to circumvent these issues for hepatitis C virus (HCV) and norovirus. We applied RNA-Seq to total RNA extracted from HIV-2 blood plasma samples, demonstrating the applicability of this technique to HIV-2 and allowing us to generate a dynamic picture of genetic diversity over the whole genome of HIV-2 in the context of low-bias sequencing.
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| 10. |
- Roth, Adam, et al.
(author)
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Effect of revaccination with BCG in early childhood on mortality: randomised trial in Guinea-Bissau
- 2010
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In: BMJ: British Medical Journal. - : BMJ. - 1756-1833. ; 340
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Journal article (peer-reviewed)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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