Search results
Results from the WOW.Com Content Network
Waterborne diseases were once wrongly explained by the miasma theory, the theory that bad air causes the spread of diseases. [27] [28] However, people started to find a correlation between water quality and waterborne diseases, which led to different water purification methods, such as sand filtering and chlorinating their drinking
The disease is common in sub-Saharan Africa, but can ultimately be found wherever Amblyomma ticks are present. Major areas of concern for the disease also include Madagascar, Mauritius, Zanzibar, the Comoros Islands, and Sao Tomé. Heartwater has been observed on three of the Caribbean islands, Guadeloupe, Marie-Galante, and Antigua.
Disease diffusion occurs when a disease is transmitted to a new location. [1] It implies that a disease spreads, or pours out, from a central source. [ 2 ] The idea of showing the spread of disease using a diffusion pattern is relatively modern, compared to earlier methods of mapping disease, which are still used today. [ 3 ]
The quality of drinking water is ensured through a framework of water safety plans that ensures the safe disposal of human waste so that drinking water supplies are not contaminated. Improving the water supply, sanitation, hygiene and management of our water resources could prevent ten percent of total global disease. [13]
In epidemiology, environmental diseases are diseases that can be directly attributed to environmental factors (as distinct from genetic factors or infection). Apart from the true monogenic genetic disorders , which are rare, environment is a major determinant of the development of disease.
The subclinical (pre-symptomatic) and clinical (symptomatic) evolution of disease is the natural progression of a disease without any medical intervention. It constitutes the course of biological events that occurs during the development of the origin of the diseases [4] to its outcome, whether that be recovery, chronicity, or death. [5]
A secondary disease is a disease that is a sequela or complication of a prior, causal disease, which is referred to as the primary disease or simply the underlying cause . For example, a bacterial infection can be primary, wherein a healthy person is exposed to bacteria and becomes infected, or it can be secondary to a primary cause, that ...
The number of cases varies according to the disease-causing agent, and the size and type of previous and existing exposure to the agent. Outbreaks include many epidemics, which term is normally only for infectious diseases, as well as diseases with an environmental origin, such as a water or foodborne disease. They may affect a region in a ...