Showing papers by "Peter Aaby published in 2004"
TL;DR: The protective effect of number of siblings, day care, pet ownership, and farm residence remained after adjustment for clinically apparent infectious diseases, suggesting that the effect is established independently early in life.
Abstract: Objectives To determine whether early infectious diseases could explain the association between number of siblings and other markers of microbial exposure and the development of atopic dermatitis before the age of 18 months. Design Cohort study. Information on atopic dermatitis, infectious diseases occurring before 6 months of age, number of siblings, early day care, pet keeping, farm residence, and background factors was collected in telephone interviews. Setting Danish national birth cohort. Participants 24 341 mother-child pairs. Main outcome measures Incidence rate ratios of atopic dermatitis. Results 13 070 children (54%) had at least one clinically apparent infectious disease before 6 months of age. At age 18 months, 2638 (10.8%) of the children had had atopic dermatitis. The risk of atopic dermatitis increased with each infectious disease before 6 months of age (incidence rate ratio 1.08, 95% confidence interval 1.04 to 1.13). The risk of atopic dermatitis decreased with each additional exposure to three or more siblings, day care, pet ownership, and farm residence (0.86, 0.81 to 0.93). Conclusions Early infections do not seem to protect against allergic diseases. The protective effect of number of siblings, day care, pet ownership, and farm residence remained after adjustment for clinically apparent infectious diseases, suggesting that the effect is established independently early in life.
217 citations
TL;DR: The significance of the family-based associations found between TB and FokI-BsmI-ApaI-TaqI and the FA haplotype supports a role for VDR haplotypes, rather than individual genotypes, in susceptibility to TB.
Abstract: Vitamin D receptor (VDR) gene polymorphisms have been implicated in susceptibility to tuberculosis (TB), but reports have been inconsistent. We genotyped the VDR single-nucleotide polymorphisms (SNPs) FokI, BsmI, ApaI, and TaqI in 1139 case patients and control subjects and 382 families from The Gambia, Guinea, and Guinea-Bissau. The transmission-disequilibrium test on family data showed a significant global association of TB with SNP combinations FokI-BsmI-ApaI-TaqI and FokI-ApaI that were driven by the increased transmission to affected offspring of the FokI F and ApaI A alleles in combination. The ApaI A allele was also transmitted to affected offspring significantly more often than expected. Case-control analysis showed no statistically significant association between TB and VDR variants. BsmI, ApaI, and TaqI showed strong linkage disequilibrium. The significance of the family-based associations found between TB and FokI-BsmI-ApaI-TaqI and the FA haplotype supports a role for VDR haplotypes, rather than individual genotypes, in susceptibility to TB.
149 citations
TL;DR: In low-income countries with high mortality, DTP as the last vaccine received may be associated with slightly increased mortality, and the role of DTP in high mortality areas needs to be clarified.
Abstract: diphtheria-tetanus-pertussis (DTP) vaccine to be associated with the expected objective reduction in mortality, a few studies suggesting increased mortality. We therefore examined mortality when DTP was first introduced in rural areas of GuineaBissau in 1984‐1987. Setting Twenty villages in four regions have been followed with bi-annual examinations since 1979. Subjects In all, 1657 children aged 2‐8 months. Design Children were weighed when attending the bi-annual examinations and they were vaccinated whenever vaccines were available. DTP was introduced in the beginning of 1984, oral polio vaccine later that year. We examined mortality for children aged 2‐8 months who had received DTP and compared them with children who had not been vaccinated because they were absent, vaccines were not available, or they were sick. Main Mortality over the next 6 months from the day of examination for vaccinated and outcome unvaccinated children. measure Results Prior to the introduction of vaccines, children who were absent at a village examination had the same mortality as children who were present. During 1984‐1987, children receiving DTP at 2‐8 months of age had higher mortality over the next 6 months, the mortality rate ratio (MR) being 1.92 (95% CI: 1.04, 3.52) compared with DTP-unvaccinated children, adjusting for age, sex, season, period, BCG, and region. The MR was 1.81 (95% CI: 0.95, 3.45) for the first dose of DTP and 4.36 (95% CI: 1.28, 14.9) for the second and third dose. BCG was associated with slightly lower mortality (MR � 0.63, 95% CI: 0.30, 1.33), the MR for DTP and BCG being significantly inversed. Following subsequent visits and further vaccinations with DTP and measles vaccine, there was no difference in vaccination coverage and subsequent mortality between the DTP-vaccinated group and the initially DTP-unvaccinated group (MR � 1.06, 95% CI: 0.78, 1.44). Conclusions In low-income countries with high mortality, DTP as the last vaccine received may be associated with slightly increased mortality. Since the pattern was inversed for BCG, the effect is unlikely to be due to higher-risk children having received vaccination. The role of DTP in high mortality areas needs to be clarified.
124 citations
TL;DR: Human immunodeficiency virus (HIV), increasing age, male sex, ethnicity, adult crowding, family structure, and poor housing conditions were independent risk factors for TB in Guinea-Bissau.
Abstract: Background Despite the long history of tuberculosis (TB) research, population-based studies from developing countries are rare. Methods In a prospective community study in Bissau, the capital of Guinea-Bissau, we assessed the impact of demographic, socioeconomic and cultural risk factors on active TB. A surveillance system in four districts of the capital identified 247 adult (greater than or equal to15 years) cases of intrathoracic TB between May 1996 and June 1998. Risk factors were evaluated comparing cases with the 25 189 adults living in the area in May 1997. Results The incidence of intrathoracic TB in the adult population was 471 per 100 000 person-years. Significant risk factors in a multivariate analysis were increasing age (P 2 adults in household), and poor quality of housing (OR = 1.66, 95% CI: 1.24, 2.22). Household type was important; adults living alone or with adults of their own sex only, had a higher risk of developing TB than households with husband and wife present, the adjusted OR being 1.76 (95% CI: 1.11, 2.78) for male households and 3.80 (95% CI: 1.69, 8.56) for female households. In a multivariate analysis excluding household type, child crowding was a protective factor, the OR being 0.68 (95% CI: 0.51, 0.90) for households with >2 children per household. Conclusions Bissau has a very high incidence of intrathoracic TB. Human immunodeficiency virus (HIV), increasing age, male sex, ethnicity, adult crowding, family structure, and poor housing conditions were independent risk factors for TB. Apart from HIV prevention, TB control programmes need to emphasize risk factors such as socioeconomic inequality, ethnic differences, crowding, and gender.
119 citations
TL;DR: The policy of not vaccinating low birth weight children at birth in Guinea-Bissau had a negative impact on vaccination coverage for LBW children and future studies should examine possible adverse effects from equalizing BCG policy.
Abstract: BACKGROUND: In developing countries, low birth weight (LBW) children are often not vaccinated with Calmette-Guerin bacillus (BCG) at birth. Recent studies have suggested that BCG may have a nonspecific beneficial effect on infant mortality. We evaluated the consequences of not vaccinating LBW children at birth in Guinea-Bissau. METHODS: Between 1989 and 1999, 7138 children born at the central hospital had a birth weight registered. We assessed BCG coverage until 3 years of age. Data on tuberculin skin test (TST) for 297 children and BCG scar for 1319 children in the study population were reanalyzed for differences between normal birth weight (NBW) children and LBW children. We assessed the effect of early BCG vaccination on mortality to 12 months of age. RESULTS: Among LBW children there were 1.5- to 3-fold more unvaccinated individuals than among NBW children up to 4 months of age. There was no overall difference between LBW and NBW children in TST or BCG scarring; LBW children vaccinated early may have had slightly reduced reactions to tuberculin. Among 845 LBW children, 182 had received BCG within the first week of life. Controlling for background factors and censoring at first diphtheria-tetanuspertussis vaccination, measles vaccination or at 6 months of age (whichever came first), the mortality rate ratio for BCG-vaccinated versus -unvaccinated LBW children was 0.17 (95% confidence interval, 0.06-0.49), with an even stronger effect for LBW children vaccinated in the first week of life (mortality rate ratio, 0.07; 95% confidence interval, 0.01-0.62). CONCLUSIONS: The policy of not vaccinating with BCG at birth had a negative impact on vaccination coverage for LBW children. Early BCG vaccination had no large negative impact on TST and BCG scarring. Mortality was lower for BCG-vaccinated than for unvaccinated LBW children controlling for available background factors. BCG vaccination of LBW children may have a beneficial effect on survival that cannot be explained by protection against tuberculosis. Future studies should examine possible adverse effects from equalizing BCG policy for LBW and NBW children.
111 citations
TL;DR: The authors found no overall effects of exclusive or partial breastfeeding on the risk of atopic dermatitis, however, the effect of exclusive breastfeeding for 4 months or more depended on parental history of allergic diseases.
Abstract: The role of breastfeeding in allergic diseases remains controversial. The authors studied the association between breastfeeding and development of atopic dermatitis during the first 18 months of life among children with and without a parental history of allergy. A cohort study of 15,430 mother-child pairs enrolled in The Danish National Birth Cohort was carried out between 1998 and 2000. Data on breastfeeding, atopic dermatitis, and potential confounders was obtained from telephone interviews conducted during pregnancy and when the children were 6 and 18 months of age. The cumulative incidence of atopic dermatitis was 11.5% at 18 months of age. Overall, current breastfeeding was not associated with atopic dermatitis (incidence rate ratio (IRR) = 0.91, 95% confidence interval (CI): 0.80, 1.04). Exclusive breastfeeding for at least 4 months was associated with an increased risk of atopic dermatitis in children with no parents with allergies (IRR = 1.29, 95% CI: 1.06, 1.55) but not for children with one (IRR = 1.11, 95% CI: 0.94, 1.31) or two (IRR = 0.88, 95% CI: 0.69, 1.13) parents with allergies (test for homogeneity, p = 0.03). The authors found no overall effects of exclusive or partial breastfeeding on the risk of atopic dermatitis. However, the effect of exclusive breastfeeding for 4 months or more depended on parental history of allergic diseases.
109 citations
TL;DR: Non-specific effects of routine vaccinations are likely to be important and influence sex-specific mortality patterns in areas with high mortality, and need to be considered in the planning of immunization programmes for low-income countries.
Abstract: BACKGROUND: Observational studies have suggested that vaccinations have non-specific effects that differ by sex. In the absence of randomized trials, studies of female-male twin pairs would allow us to investigate whether an intervention had sex-specific effects on survival. We therefore examined mortality patterns among female-male twin pairs according to vaccination status. Design We identified female-male twin pairs using the population registers from one urban district and three rural studies from Guinea-Bissau and Senegal and examined the female-male mortality ratio (MR) according to the last vaccine received among pairs in which a death occurred before 18 months of age. As background information, we examined sex- and age-specific mortality patterns in the pre-vaccination era. Subjects In all, 626 female-male twin pairs identified between 1978 and 2000. RESULTS: There was no sex difference in mortality for boys and girls in the pre-vaccination era. In the combined analysis of all studies, the female-male MR was 0.25 (95% CI: 0.05, 0.93) for pairs having received Bacille Calmette-Guerin (BCG) as the last vaccine, 7.33 (95% CI: 2.20, 38.3) for pairs having received diphtheria, tetanus, pertussis (DTP) as the last vaccine, and 0.40 (95% CI: 0.04, 2.44) for pairs having received measles vaccine as the last vaccine. The female-male MR varied significantly for BCG compared with DTP (exact test of homogeneity, P < 0.001) and for DTP compared with measles vaccine (exact test of homogeneity, P = 0.001). CONCLUSION: Non-specific effects of routine vaccinations are likely to be important and influence sex-specific mortality patterns in areas with high mortality. The effects of vaccines need to be considered in the planning of immunization programmes for low-income countries.
91 citations
TL;DR: The shortage of DTP vaccine in Bissau was used to examine the impact of OPV on the case fatality at the paediatric ward in BISSau and found that having received OPV only was associated with a casefatality compared with 15% for children having received combined DTP and OPV vaccinations.
73 citations
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TL;DR: Comparisons suggested changes in the mortality pattern after the introduction of HBV, particularly for girls, in areas with high mortality, HBV may affect girls’ and boys’ susceptibility to infections differently.
Abstract: Objective: Studies from high mortality areas have suggested that diphtheria-tetanus-pertussis may be associated with an increase in the mortality of girls relative to boys. We therefore examined whether hepatitis B vaccine (HBV) was associated with sex-specific differences in mortality. Design: As part of a randomized trial of measles vaccine a subcohort of 876 children was offered HBV at 7½ 9 and 10½ months of age. We examined whether this cohort differed in mortality rate and female-male mortality ratio compared with previous and subsequent birth cohort enrolled in the same trial. Setting: Four districts in Bissau the capital of Guinea-Bissau. Subjects: Six annual birth cohorts of 8906 children registered in the study area and followed from 1½ to 12 months of age between March 1995 and February 2001. Of these children 6399 took part in a 2-dose measles vaccination trial; of those born between March 1996 and February 1997 876 received HBV. Main Outcome Measures: (1) The mortality rate ratio (MR) between 7½ and 12 months and 1½ and 7½ months old children; (2) the female-male MR among trial children having received HBV plus measles vaccine or only measles vaccine. Results: In cohorts not receiving HBV the MR for children 7½-12 and 1½-7½ months of age was 0.97 [95% confidence interval (95% CI). 0.79- 1.24] whereas the MR was 1.62 (95% CI 1.09-2.41) in the cohort receiving HBV at 7½ months (test of homogeneity P = 0.030). Among children enrolled in the measles vaccination trial HBV-vaccinated children 7½-12 months of age had higher mortality than both prior and subsequent cohorts who had not received HBV (MR = 1.81; 95% CI 1.19-2.75) the difference being particularly strong for girls (MR=2.27; 95% CI 1.31-3.94). In the cohort who had received both HBV and measles vaccine the female-male MR between 9 and 24 months of age was 2.20 (95% CI 1.07-4.54) compared with 0.96 (95% CI 0.70-1.32) in trial participants who had received measles vaccine only (test for homogeneity P = 0.040). With longer follow-up these tendencies remained the same. Conclusions: These comparisons suggested changes in the mortality pattern after the introduction of HBV particularly for girls. Hence in areas with high mortality. HBV may affect girls and boys susceptibility to infections differently. (authors)
59 citations
TL;DR: This study demonstrates an important association between suPAR and acute malaria infection in humans and investigates suPAR levels during symptomatic malaria infection and 7 days after treatment.
Abstract: SUMMARY
Serum levels of soluble urokinase plasminogen activator receptor (suPAR) are significantly elevated and of prognostic value in patients suffering from serious infectious diseases such as HIV and tuberculosis. Our objective was to investigate suPAR levels during symptomatic malaria infection and 7 days after treatment. Children younger than 6 years who presented with fever or other symptoms compatible with malaria were enrolled. Blood films and samples were collected on day 0 and day 7. Twenty-five children were allocated to each of three groups according to the amount of Plasmodium falciparum detected in their initial blood film. Children in group 1 had parasite densities in excess of 20 parasites per 200 leucocytes. The median plasma suPAR level was 6·49 ng/mL (interquartile range [IQR]: 4·90–7·61) and correlated to parasitemia (Spearman 0·43, P < 0·0001). Blood was obtained from 20 children in group 1 after 7 days of treatment. All became malaria negative in their blood slides and all decreased in suPAR level to median 3·48 ng/mL (IQR: 3·08–3·91) (P < 0·0001). Group 2 consisted of 25 children with 1–20 parasites in their blood slide. The suPAR level was median 2·91 ng/mL (IQR: 2·27–4·40) and decreased with median 0·5 ng/mL following treatment (P = 0·0002). Group 3 showed to be negative in their blood slides and most received antibiotic treatment. suPAR decreased from median 3·26 ng/mL (IQR: 2·77–4·46) to median 2·47 ng/mL (IQR: 2·01–3·75), on day 7 (P = 0·006). This study demonstrates an important association between suPAR and acute malaria infection in humans.
43 citations
TL;DR: Although orphan children remained disadvantaged, there were few differences between surviving motherless and control children in nutritional status, use of health care services, school attendance, quality of housing, and clothing.
TL;DR: This study found no increased risk of death among young adults born during the hungry season in a rural West African area despite large seasonal variations in women's nutritional status.
Abstract: BACKGROUND In a rural area of the Gambia, West Africa, young adults born in the 'hungry' season had a high excess of deaths (mortality ratios (MR): 3.7 from 14.5 years and 10.3 from 25 years, P < 0.0001). Among several potential causal factors, fetal undernutrition was considered the most plausible. This study is a similar analysis of children and young adults living in rural Senegal, close to the Gambia. METHODS A cohort of 9192 subjects born 1962-2001 with prospectively collected dates of birth and death was analysed. MR by season of birth (July-December/January-June) was estimated using Cox's proportional hazards analysis. The nutritional status of non-pregnant women was analysed at monthly intervals 1990-1996. RESULTS MR by season of birth was slightly greater than 1 during infancy, and close to 1 from 1-5 years and from 5-14.5 years. From 14.5 years old the MR was 0.77 (95% CI: 0.47, 1.25, P = 0.29), compared with 0.53 (95% CI: 0.28, 1.02, P = 0.056) from 20 years and 0.33 (95% CI: 0.09, 1.25, P = 0.10) from 25 years. The weight of women varied strongly by season: means were 3.0-3.9 kg lower at the end of the rainy season (September-November) than during the dry season (February-May, P < 0.001 for each year). CONCLUSIONS This study found no increased risk of death among young adults born during the hungry season in a rural West African area despite large seasonal variations in women's nutritional status. The strongly increased risk in adult Gambians is probably not explained by fetal undernutrition.
TL;DR: The possibilities of promoting home treatment for malaria treatment should be further evaluated, not only to avoid unnecessary visits to the professional health system, but also to decrease the morbidity from acute malaria.
TL;DR: Nielsen et al. as mentioned in this paper found that a history of poliomyelitis was associated with a slightly increased morbidity measured by hospitalizations, and the long-term morbidity was highest among respiratory polio patients.
TL;DR: The home-based SFP probably prevented nutritional deterioration during the war in Guinea-Bissau, and better compliance was associated with shorter time to recovery.
TL;DR: HIV-2-specific serum IgA antigen reactivity is described and a more potent Serum IgA-mediated HIV-1-neutralizing activity is shown in EGSN individuals than in HIV- 2-infected patients.
Abstract: The mechanisms behind the resistance to human immunodeficiency virus type 2 (HIV-2) infection are still not fully understood. In the present study, we explored the HIV-2-specific humoral serum immunoglobulin A (IgA) immune response in HIV-2-exposed IgG-seronegative (EGSN) individuals. Serum samples from heterosexual EGSN individuals and their known HIV-2-infected partners, as well as controls originating from Guinea-Bissau in Africa, were studied. Antibody reactivity to native and recombinant envelope glycoproteins was investigated, and the capacity of purified serum IgA to neutralize HIV-2SBL6669 was tested. Our results showed that 16 of 25 EGSN samples exhibited reactivity against whole HIV-2 antigen, 6 of 25 samples reacted with recombinant gp36 (rgp36), and 3 of 25 samples were positive against HIV-2 rgp105; no reactivity to native HIV-2 gp125 was detected. Purified serum IgA antibodies from both EGSN and HIV-2-positive individuals, but not that from the negative controls, exhibited neutralization of HIV-2SBL6669. The most potent neutralization activity was exhibited by IgA purified from EGSN compared to infected individuals' IgA. The antigenic pattern of the HIV-2-positive partners showed that all serum IgA samples were reactive to whole HIV-2 antigen, and 14 of 15 reacted with rgp36. For rgp105 and gp125, 5 of 15 and 4 of 15 samples exhibited binding, respectively. The serum of the EGSN group had a higher mean IgA concentration than that of the negative controls (P < 0.05). Thus, we describe HIV-2-specific serum IgA antigen reactivity and show a more potent serum IgA-mediated HIV-2-neutralizing activity in EGSN individuals than in HIV-2-infected patients.
TL;DR: Because most strains that had the same toxin-CF profile were closely related, it seems likely that the toxin- CF-specific protection was clonal and was not targeting antigens encoded by the virulence plasmids.
Abstract: In a cohort study of 200 young children in Guinea-Bissau, it was previously found that some enterotoxigenic Escherichia coli (ETEC) strains were more pathogenic than others, depending on the type of toxin that they could produce, and that natural ETEC infections induced substantial protection against new infections with ETEC strains that had the same combination of toxins and colonization factors (CFs). We wanted to describe the clonal relatedness of the ETEC strains isolated during this study and to investigate whether the protective antigens and the virulence factors that were responsible for the pathogenic traits were common to strains that were clonally closely related or whether they were more likely to be encoded by the ETEC virulence plasmids that normally encode the toxins and the CFs. By performing repetitive sequence-based PCR analysis of strains representing 452 infections, we found that strains that had the same toxin-CF profile were usually closely related, although a few were unrelated. Strains that did not have the same toxin-CF profiles but that were positive for a given toxin or for a given CF were not consistently more closely related to each other than to strains that were negative for the same toxin or CF. Our results indicate that the pathogenic traits of ETEC were mainly attributed to genes carried on the ETEC virulence plasmids. Because most strains that had the same toxin-CF profile were closely related, it seems likely that the toxin-CF-specific protection was clonal and was not targeting antigens encoded by the virulence plasmids. These results are of relevance to the ETEC vaccine development effort.
TL;DR: The case fatality among children aged 0–14 y fell during the war in Guinea‐Bissau and was most marked for disadvantaged groups, while post‐hospital mortality in the 2 wk after discharge as well as socio‐economic differences in recruitment during thewar made no difference.
Abstract: BACKGROUND: During a recent armed conflict in Guinea-Bissau, we observed a marked decline in the case fatality among hospitalized children at the only paediatric department in the country. AIM: To analyse the causes behind the observed fall in case fatality. MATERIAL: All children hospitalized at the only paediatric department in the capital of Guinea-Bissau. The war cohort comprised all children hospitalized during the war, which lasted from June 1998 to May 1999, and the peace cohort comprised all children hospitalized in the year preceding the war. As part of a longitudinal community study, we also registered all children being hospitalized from the Bandim Health Project's study area, including routinely collected information on socio-economic background factors. METHODS: The war cohort was compared with the peace cohort in terms of determinants for hospital case fatality. Through information in the community register, we examined post-hospital mortality in the 2 wk after discharge as well as socio-economic differences in recruitment during the war. Hospital case fatality was estimated by odds ratios and compared by multiple logistic regression. Community mortality risk was estimated by deaths per person years. RESULTS: The case fatality among children aged 0-14 y fell during the war (age-adjusted OR = 0.58; 95% CI: 0.50-0.68). There was a uniform reduction in case fatality among children hospitalized less than 7 d, while we observed no decline among children hospitalized longer. There were more children per bed during the war and mean hospitalization time was shorter, and post-discharge mortality also fell (mortality ratio (MR) = 0.57; 95% CI: 0.40-0.83). Adjustment for socio-economic confounders in recruitment during the war period made no difference to the estimated decline in case fatality. The decline in case fatality at the hospital was not explained by a general decline in mortality. Compared with the preceding year, the mortality ratio was 1.34 (1.20-1.51) in the Bandim Health Project's study area during the war. Adjusted for age, the decline in case fatality at the hospital was most marked for disadvantaged groups. For example, the general reduction in case fatality was 42% (95% CI: 11-63); however, children of mothers without any schooling experienced a reduction of 73% (95% CI: 27-90%), whereas the reduction was only 33% (95% CI: 14-61%) for children of mothers with school education. CONCLUSION: The decline in case fatality could be explained neither by a general decline in childhood mortality nor by changes in recruitment or discharge policy. The decline was therefore most likely due to improved treatment as a result of better availability of drugs funded by humanitarian aid and the presence of dedicated staff, which was offered relief food as compensation. Interventions improving case management may have a proportionately larger effect for poor families. (Less)
TL;DR: Mothers may transmit respiratory syncytial virus more easily or severely to sons, particularly in small families with few individuals contributing to transmission.
Abstract: Opposite gender transmission may increase the severity of certain infections. If infections transmitted from mother to son were more severe than from mother to daughter this might explain severe diseases among boys, particularly in small families with few individuals contributing to transmission. Among children from Guinea-Bissau, we tested whether mothers with recent respiratory syncytial virus exposure (positive IgM and IgA antibody responses) were more likely to have male than female children with respiratory syncytial virus antigen positive acute lower respiratory tract infection. Children with acute lower respiratory tract infection were identified at a paediatric clinic (n = 348), a health centre (n = 270), and in a community morbidity survey (n = 525), 14.2% (162/1143) having respiratory syncytial virus antigen. An equal number of boys and girls had acute lower respiratory tract infection, but boys were more likely to have respiratory syncytial virus detected (prevalence ratio = 1.36 (1.01-1.81)), this difference being particularly marked in the rainy season. With recent respiratory syncytial virus exposure of mother, boys were twice as likely to have respiratory syncytial virus detected (prevalence ratio = 2.04 (1.18-3.53)), the difference being marked in the rainy season. There was no gender difference in respiratory syncytial virus infection among children of RSV negative mothers. We conclude that mothers may transmit respiratory syncytial virus more easily or severely to sons.
TL;DR: A study of routine immunizations in rural areas of Guinea-Bissau suggested that early BCG and measles vaccination were associated with reduced mortality which was not explained by the prevention of TB or measles but that early diphtheria-tetanus-pertussis (DTP) vaccine was associated with increased mortality.
Abstract: About four years ago a study of routine immunizations in rural areas of Guinea-Bissau suggested that early BCG and measles vaccination (MV) were associated with reduced mortality which was not explained by the prevention of TB or measles but that early diphtheria-tetanus-pertussis (DTP) vaccine was associated with increased mortality. Given the observational design and the potential for bias a precise estimate of these effects could not be established but it was noteworthy that different vaccines had opposite effects. Several studies from Bissau Senegal and Benin have found similar patterns of BCG and MV being associated with lower mortality and DTP with higher mortality. These effects are most marked immediately after vaccination and until the next vaccine is received. When DTP has been the last vaccine received it has been associated with a higher mortality for girls. WHO withdrew high-titre measles vaccine (HTMV) because it was associated with increased female mortality; however the higher mortality may have been because the measles vaccine was followed by DTP vaccine rather than any direct adverse effect of HTMV. (excerpt)
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