(A) Natives attacking workers
(B) Wild animal attacks
(C) ** Mosquitoes carrying diseases
(D) Not enough money
EXPLANATIONS BELOW
Concept note-1: -The control of malaria was vital for the construction of the Panama Canal. The discovery by Major Ronald Ross that malaria was transmitted by mosquitoes had tremendous impact on development programs in the tropics.
Concept note-2: -“There is too much water, the rocks are exceedingly hard, the soil is very hilly and the climate is deadly. The country is literally poisoned, ” complained senior French engineer Adolphe Godin de Lépinay. Outbreaks of dysentery and epidemics of yellow fever and malaria decimated the workforce.
Concept note-3: -An estimated 12, 000 workers had died during the construction of the Panama Railway and over 22, 000 during the French effort to build a canal. Many of these deaths were due to disease, particularly yellow fever and malaria.
Concept note-4: -His team implemented a multilayered approach to mosquito control in Panama. They drained pooled water within 100 meters of houses, killed mosquito larva with chemicals, put screens on windows to prevent mosquito entry, and more. By 1906, the Zone was free of yellow fever, and eradication of malaria soon followed.
Concept note-5: -The most effective prevention against malaria and dengue fever is to protect yourself against mosquito bites. Dietary Distress–Hepatitis A is a highly contagious viral disease and one of the most common travel-related infections in the developing world.