Please select the eligibility criteria that correspond to the clinical trial below.
Title: Evaluation of the Impact on Mortality and Morbidity of the WHO Recommended Vitamin A Supplementation at First Immunisation Contact After 6 Months of Age
Brief Summary: High-dose vitamin A to children above 6 months of age reduces all-cause mortality by 23-30%. The WHO recommends vitamin A supplementation (VAS) with the first vaccine after 6 months of age. However, the effect of providing VAS with vaccines has never been investigated. We have hypothesised that the effect of VAS depends on the immune stimulus at the time of supplementation. Hence, the effect might vary depending on which type of vaccine it is given with. In particular, we hypothesised that VAS might be beneficial when given with measles vaccine but not when given with DTP vaccine. Normally the first vaccine after 6 months of age would be a measles vaccine, but many children come late for their DTP vaccinations and receive DTP alone or together with measles vaccine. Hence, it is important to study whether the effect of VAS is the same irrespective of the vaccine(s) administered at the same time.

Guinea-Bissau has not yet implemented the WHO vitamin A policy of providing VAS with vaccines, but plans to do so within the next years. Together with the Ministry of Health in Guinea-Bissau, the Bandim Health Project (BHP) in Guinea-Bissau will investigate the effect on mortality and morbidity of implementing the WHO vitamin A policy in Guinea-Bissau. This will be done in a large randomised trial.

BHP has a demographic surveillance system (DSS) which has followed a population of now more than 150,000 individuals for almost 30 years. Children will be randomised to receive VAS or placebo with their first vaccine after 6 months of age, and will be followed through the DSS to assess mortality and morbidity. Based on previous observations, the effects of VAS might differ according to sex and season. The interaction between VAS, sex, and season will also be studied in the present trial. By identifying situations where VAS may be beneficial, ineffective, or even harmful the study may contribute importantly to optimising the VAS policy for low-income countries.


Options:
A: 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.
B: Inclusion Criteria:

4-6 months of age (stratified by HIV status) Infant able to take oral preparations Consent of parent/guardian HIV status obtained from mother and child

Exclusion Criteria:

Documented micronutrient supplementation other than vitamin A in the preceding month Less than 60% of mean weight for age by NCHS guidelines (micronutrient intervention obligatory according to WHO guidelines for management of severely malnourished children) Persistent diarrhea (\>=7 days) at the time of study enrollment Exclusive breastfeeding Infants in whom a second confirmatory HIV test cannot be obtained (when required) Co-enrollment of the infant in other clinical intervention trials e.g. antibiotic or vaccine trials
C: Inclusion Criteria:

* Age 7-12 years (according to birth date in birth certificate).
* No evidence of concomitant severe and/or chronic illness such as acute respiratory tract infections, mental retardation and neurological deficits.
* Consent of parent to participate in the study.

Exclusion Criteria:

* history or evidence of underlying haematological-related diseases such as thalassaemia and ovalocytosis.
* menstruating females (age \>13)
D: Inclusion Criteria:

1. Children aged 57-88 months at the time of initiation of the study
2. Children living in the locality defined by the study and not enrolled in school.
3. Consent from parent/guardian.

Exclusion Criteria:

1. Severely malnourished children (weight for age or height z-scores \<-3 standard deviations below the WHO growth reference standards)
2. Children found to be below 57 months and still holding an under five card or above 88 months at the time of initiation of the study or enrolled in school, based on verification of birth dates at screening
3. Children whose families plan to leave the study area before completion of the study
4. Consent not obtained from parent/guardian
5. Children suffering from diarrhea at the time of initiation of the study or with high fever, based on the report of symptoms by the parent/guardian
6. Children with severe anemia (Hb \<7.0 g/dL) as determined at the baseline blood draw.

Answer: A