Please select the eligibility criteria that correspond to the clinical trial below.
Title: Newborn Vitamin A Supplementation, Gut Microbiota and Vaccine Response During the Second Year of Life in Bangladeshi Infants
Brief Summary: Vitamin A deficiency (VAD) increases the risk of death from infections in infants and young children. The World Health Organization (WHO) recommends high-dose vitamin A supplementation (VAS) from 6-59 months of age to reduce the risk of death in countries where VAD is common. Such countries include Bangladesh, where this study is being conducted. While providing VAS at 6 months is recommended, providing VAS at birth may also decrease the risk of death since newborn infants are also at risk of VAD. VAS presumably reduces infant mortality by improving the immune response to infection and immunization. Vitamin A particularly affects the development and function of T cells, which develop in the thymus and are a key component of the memory response to infection and immunization. Vitamin A is important for development of an important class of T cells, regulatory T-cells, in the intestine. Regulatory T-cells prevent over-reaction of the immune system to substances the immune system might otherwise treat as harmful such as food or the healthy bacteria in the intestine. VAD could disrupt the normal colonization of the infant's intestinal tract and cause a condition called "dysbiosis" where abnormal bacteria flourish and adversely affect the infant's immune system. Dysbiosis may disrupt the immune response to injectable and oral vaccines. VAS at birth may prevent dysbiosis and thus improve immune function, response to vaccines, and child survival. The investigators recently completed an intervention trial in Bangladeshi infants (NCT01583972) examining the effect of VAS at birth on immune function and response to vaccines administered from birth to 14 wk of age. The present study will recruit infants who completed NCT01583972 when they are from 12 to 24 m of age to determine if VAS at birth affects the responses to these same vaccines when they are measured during the second year of life. The investigators will examine the effect of VAS at birth on gut microbiota measured early in infancy and during the second year of life, and explore the association of the gut microbiota with vaccine response. Mothers of study infants will participate in the study because the breast milk oligosaccharide content strongly affects gut microbiota composition and the "secretor status" of the mother, which can be determined from maternal FUT2 genotype, strongly affects breast milk oligosaccharide content.


Options:
A: Inclusion Criteria:

* Pregnant low-risk obstetric

Exclusion Criteria:

* Premature birth
* Newborn babies with birth defects and / or other serious diseases
B: Inclusion Criteria:

* for infant: completion of NCT01583972
* for mother: mother of study infant

Exclusion Criteria:

* none
C: Inclusion Criteria:

* Lives in a selected cluster
* Is \>= 6 months pregnant
* Has no plans to move outside of the cluster within 1 year

Exclusion Criteria:

* Reduced ability to collaborate for psychological/mental reasons
* Severely ill
* Has given birth more than 7 days ago
* Has given birth less than 7 days ago and it was a multiple birth; or the child has a severe malformation; or death of the mother or the baby.
D: Inclusion Criteria:

* Urban area: 6-17-month-old children, presenting for vaccination at a health centre in the study area.
* Rural area: 6-23-month-old children who are missing one or more routine vaccinations when visited by our mobile team.

Exclusion Criteria:

* Normally applied contraindications for receiving vaccinations, including high fever.
* VAS within last month.

Answer: B