Correlates of Protection in Ghana
Condition: Malaria
MeSH terms: Malaria
Study type: Observational

Summary: 
      Malaria is a sickness passed from one person to the other by the bite of a mosquito. In areas
      of frequent malaria infection, children may develop natural protection against malaria and
      they are less likely to become sick or die from it as they age. The purpose of this study is
      to investigate the body's natural protection against malaria in children by testing their
      blood. This information may help investigators develop a malaria vaccine. The Navrongo Health
      Research Centre is conducting this study in Ghana. Three hundred healthy children between the
      ages of 1 and 5 years will participate in the study for 12 months. Study procedures will
      include 7 field worker visits to check on the child's health and obtain a blood sample. Every
      two months, a blood sample will be taken from each child to test it for strength against
      malaria. Whenever a child is sick, the child will be tested for malaria.
    

Detailed description: 
      The principal aim of this study is to identify immunological correlates of naturally acquired
      immunity to malaria in young children in the process of acquiring clinical immunity. As a
      secondary aim, the investigators will study whether allele specific immune responses provide
      only allele-specific protection against symptomatic infection. Finally, the investigators
      will assess the baseline immune responses and the extent to which they are boosted during the
      malaria transmission season in a population likely to be involved in malaria vaccine trials
      in the near future. The overall study design is to enroll 300 healthy children, aged 1-5
      years, located in the northern section of the Kassena-Nankana district and to follow them for
      twelve months, including the entire high malaria transmission season. They will be evaluated
      upon enrollment, bimonthly, and at the close of the study by physical examination, malaria
      smear, hemoglobin determination, and analysis of levels of specific antibody directed against
      a panel of candidate malaria vaccine antigens. Throughout the course of the study the
      children will be followed with passive case detection. In between the scheduled visits,
      parents will be encouraged to bring their children to the Paga Health Centre or Navrongo War
      Memorial Hospital or to a field worker anytime that they believe the child is not well. At
      such visits, the child will be evaluated with a morbidity questionnaire including a physical
      examination. A blood smear will be taken and a rapid malaria diagnostic test (DiaMed Optimal
      Rapid Malaria test) and hemoglobin measurement will be performed at the time of the visit.
      Treatment decisions will be based on clinical assessment and the result of the rapid malaria
      test. The smear result will not be available at the time initial treatment decisions are
      made. Children diagnosed with malaria will be treated with standard therapy per Ghana
      Ministry of Health policy by Ghana Health Service personnel. Children suffering from severe
      anemia or from any form of severe malaria will be referred to the Navrongo War Memorial
      Hospital for definitive treatment, including intravenous anti-malarial therapy and
      transfusion, if indicated, at no cost to the subject. At the time of discharge the subject
      will be evaluated by a study physician with a history and physical, malaria smear and
      hemoglobin determination. If in the clinical judgment of the study physician no further
      treatment is required, the subject will resume participation in the study.
    

Time perspective: Prospective
Keywords: malaria, children, naturally acquired immunity, Ghana