Rejuvenating conventional dendritic cells and T follicular helper cell formation after vaccination.

Germinal centres (GCs) are T follicular helper cell (Tfh)-dependent structures that form in response to vaccination, producing long-lived antibody secreting plasma cells and memory B cells that protect against subsequent infection. With advancing age the GC and Tfh cell response declines, resulting in impaired humoral immunity. We sought to discover what underpins the poor Tfh cell response in ageing and whether it is possible to correct it. Here, we demonstrate that older people and aged mice have impaired Tfh cell differentiation upon vaccination. This deficit is preceded by poor activation of conventional dendritic cells type 2 (cDC2) due to reduced type 1 interferon signalling. Importantly, the Tfh and cDC2 cell response can be boosted in aged mice by treatment with a TLR7 agonist. This demonstrates that age-associated defects in the cDC2 and Tfh cell response are not irreversible and can be enhanced to improve vaccine responses in older individuals

The accuracy of dietary recall of infant feeding and food allergen data.

BACKGROUND: Research investigating the association of infant dietary factors with later health outcomes often relies on maternal recall. It is unclear what the effect of recall bias is on the accuracy of the information obtained. The present study aimed to determine the extent of recall bias on the accuracy of infant feeding and food allergen data collected 10 years later. METHODS: Mothers were recruited from a prospective birth cohort from the Isle of Wight. When their child was 10 years of age (2011/2012), mothers were requested to complete a retrospective infant feeding questionnaire asking the same questions as those solicited in 2001/2002. RESULTS: In total, 125 mothers participated. There was substantial agreement for recollection of any breastfeeding (κ = 0.79) and the duration of breastfeeding from 10 years earlier (r = 0.84). Some 94% of mothers recalled accurately that their child had received formula milk. The exact age at which formula milk was first given was reliably answered (r = 0.63). The brand of formula milk was poorly recalled. Recall of age of introduction of solid food was not reliable (r = 0.16). The age of introduction of peanuts was the only food allergen that was recalled accurately (86%). CONCLUSIONS: The present study highlights the importance of maternal recall bias of infant feeding practices over 10 years. Recall related to breastfeeding and formula feeding were reliable, whereas recalls related to age of introduction of solid or allergenic foods, apart from peanut, were not. Caution should be applied when interpreting studies relying on dietary recall

Methods of nutrition surveillance in low-income countries

Background In 1974 a joint FAO/UNICEF/WHO Expert Committee met to develop methods for nutrition surveillance. There has been much interest and activity in this topic since then, however there is a lack of guidance for practitioners and confusion exists around the terminology of nutrition surveillance. In this paper we propose a classification of data collection activities, consider the technical issues for each category, and examine the potential applications and challenges related to information and communication technology. Analysis There are three major approaches used to collect primary data for nutrition surveillance: repeated cross-sectional surveys; community-based sentinel monitoring; and the collection of data in schools. There are three major sources of secondary data for surveillance: from feeding centres, health facilities, and community-based data collection, including mass screening for malnutrition in children. Surveillance systems involving repeated surveys are suitable for monitoring and comparing national trends and for planning and policy development. To plan at a local level, surveys at district level or in programme implementation areas are ideal, but given the usually high cost of primary data collection, data obtained from health systems are more appropriate provided they are interpreted with caution and with contextual information. For early warning, data from health systems and sentinel site assessments may be valuable, if consistent in their methods of collection and any systematic bias is deemed to be steady. For evaluation purposes, surveillance systems can only give plausible evidence of whether a programme is effective. However the implementation of programmes can be monitored as long as data are collected on process indicators such as access to, and use of, services. Surveillance systems also have an important role to provide information that can be used for advocacy and for promoting accountability for actions or lack of actions, including service delivery. Conclusion This paper identifies issues that affect the collection of nutrition surveillance data, and proposes definitions of terms to differentiate between diverse sources of data of variable accuracy and validity. Increased interest in nutrition globally has resulted in high level commitments to reduce and prevent undernutrition. This review helps to address the need for accurate and regular data to convert these commitments into practice

Maternal factors associated with birth weight in term infants, Colombia, 2002-2011

ABSTRACT: The study aimed to identify maternal factors associated with birth weight in Colombia from 2002 to 2011. This was a descriptive study based on data from the Live Birth Registry of Colombia, Administrative Department of Vital Statistics. Birth weight was classified as low birth weight < 2,500g, insufficient birth weight 2,500-2,999g, normal birth weight 3,000-3,999g, and high birth weight ≥ 4,000g. Data analysis used Mann-Whitney U test, Kruskal-Wallis test, and multinomial logistic regression. Women with increased likelihood of low birth weight newborns were 35 years or older (OR = 1.4; 95%CI: 1.39-1.4), had little schooling (OR = 1.1; 95%CI: 1.1-1.1), were single (OR = 1.1; 95%CI: 1.1-1.2), without prenatal care (OR = 1.9; 95%CI: 1.9-2.0), and lived in rural areas (OR = 1.2; 95%CI: 1.1-1.2). Women with higher prevalence of high birth weight newborns were 35 years or older (OR = 1.1; 95%CI: 1.1-1.1) and had four or more children (OR = 2.1; 95%CI 2.0-2.1). Insufficient birth weight showed a similar pattern to low birth weight. In conclusion, social, demographic, and maternal factors influence the birth weight of newborns in Colombia.RESUMEN: El estudio tuvo como objetivo identificar los factores maternos asociados con el peso al nacer, en Colombia, entre 2002-2011. Fue un estudio descriptivo, basado en información del Registro de Nacido Vivo de Colombia del Departamento Administrativo de Estadísticas Vitales, se clasificó el peso al nacer como: bajo peso al nacer < 2.500g, peso insuficiente 2.500- 2.999g, peso adecuado 3.000-3.999g y macrosomía ≥ 4.000g. Para el análisis se utilizó la U Mann-Whitney, Kruskall Wallis y un modelo de regresión logística multinomial. Las mujeres con mayor probabilidad de recién nacidos con bajo peso fueron las de 35 años o más (OR = 1,4; IC95%: 1,39- 1,4), con bajo nivel educativo (OR = 1,1; IC95%: 1,1-1,1), solteras (OR = 1,1; IC95%: 1,1-1,2), sin asistencia a controles prenatales (OR = 1,9; IC95%: 1,9-2,0) y de la zona rural (OR = 1,2; IC95%: 1,1-1,2). Las mujeres con mayor prevalencia de recién nacidos macrosómicos fueron de 35 años o más (OR = 1,1; IC95%: 1,1-1,1) y de 4 hijos o más (OR = 2,1; IC95%: 2,0-2,1). El peso insuficiente tuvo un comportamiento similar al bajo peso al nacer. En conclusión, los factores sociodemográficos y maternos influencian el peso al nacer de recién nacidos de mujeres colombianas

Impact of the Spanish Smoking Law on Exposure to Second-Hand Smoke and Respiratory Health in Hospitality Workers: A Cohort Study

A smoke-free law came into effect in Spain on 1st January 2006, affecting all enclosed workplaces except hospitality venues, whose proprietors can choose among totally a smoke-free policy, a partial restriction with designated smoking areas, or no restriction on smoking on the premises. We aimed to evaluate the impact of the law among hospitality workers by assessing second-hand smoke (SHS) exposure and the frequency of respiratory symptoms before and one year after the ban