Malaria Control Challenges

Challenges in Controlling Malaria

• Efforts to control mosquito vectors, particularly the A. gambiae complex, are hindered by financial constraints and insecticide resistance.
• Poverty in endemic regions severely limits programs to treat and control malaria.
• Malaria parasites have consistently developed resistance to available drugs.
• A highly effective malaria vaccine is lacking.
• Incomplete understanding of Plasmodia biology and host response to parasite infection hinders the development of new control strategies.

White Blood Cells

• There are five types of leukocytes found in peripheral blood: neutrophils, eosinophils, basophils (granulocytes), lymphocytes, and monocytes.
• All white blood cells have nuclei, which distinguishes them from other blood cells and platelets.

Neutrophils

• Neutrophils are the most abundant granulocytes, occupying 40-70% of total white blood cells.
• They are formed from stem cells in the bone marrow and released into peripheral blood, where they circulate for 7-10 hours before migrating into tissues.
• Neutrophils are highly motile, allowing them to move in and out of cells and tissues during infection.
• They are divided into two groups: neutrophil-killers and neutrophil-cagers.
• Neutrophils are part of the innate immune system and respond to inflammation, migrating towards the site of inflammation through chemotaxis.

Neutrophil Test

• The Absolute Neutrophil Count (ANC) measures the number of neutrophils and other granulocytes present in a blood sample.
• ANC is usually performed as part of a complete blood count to measure different blood cells.
• The test measures mature and immature neutrophils, with abnormal counts associated with various medical conditions.

Neutrophil Normal Range

• The normal range of ANC count in adults: 1500-8000 cells/mm³.
• The normal range of mature/segmented neutrophils: 2500-6000 cells/mm³.
• The normal range of immature/band neutrophils: 0-500 cells/mm³.
• In terms of percentage of WBC:
  • The normal range of ANC count in adults: 40-45%.
  • The normal range of mature/segmented neutrophils: 40-60%.
  • The normal range of immature neutrophils: 0-5%.

Neutropenia

• Neutropenia is a decrease in circulating neutrophils, characterized by a count of less than 1500/μL.
• It results from decreased production of neutrophils or increased destruction of these cells.
• Granulocytopenia is defined as a reduced number of blood granulocytes (neutrophils, eosinophils, and basophils).
• Grading of neutropenia:
  • Grade 1: 1,500/μL - lower limit of normal
  • Grade 2: 1,000/μL -
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