Incubation Period (Pre–patent Period) of Hookworm Infection
Following infection, the pre–patent period for N americanus is seven weeks while that for A. duodenale is unpredictable, ranging from five weeks to nine months. This is because the invading larvae of A duodenale is capable of remaining arrested or dormant in the tissues of the host for as long as nine months, and then again resume development and migrate.
Clinical Features of Hookworm Infection
Hookworm infection cause chronic blood loss and depletion of body’s iron stores leading to iron–deficiency anemia. This has implications for child health in terms of retarded physical growth and development, for the health of mothers in terms of increased morbidity, low birth weight babies, abortion, stillbirths and impaired lactation, and for the health of adults in terms of diminished capacity for sustained hard work. Hookworm infection also cause a loss of blood plasma into the small intestine which can lead to hypoalbuminaemia in some subjects.
Hookworm infection exerts a significant and harmful effect on various aspects of the economy and the quality of life of a community, especially in three major areas. These are nutrition, growth and development work, and productivity and medical care costs.