Earth's water is always in movement, and the natural water cycle, also known as the hydrologic cycle, describes the continuous movement of water on, above, and below the surface of the Earth. The hydrologic cycle begins with the evaporation of water from the surface of the ocean. As moist air is lifted, it cools and water vapor condenses to form clouds. Moisture is transported around the globe until it returns to the surface as precipitation. Groundwater either seeps its way to into the oceans, rivers, and streams, or is released back into the atmosphere through transpiration. The balance of water that remains on the earth's surface is runoff, which empties into lakes, rivers and streams and is carried back to the oceans, where the cycle begins again.
The zika virus' 1% incidence rate in the population has no effect over the probability of the patient being infected or not. If the test has a 3% false positive rate that means that if it is positive, the results have a 97% chance of being true. Therefore the chance that the person who took the test and had a positive result being actually infected is 97%.