Read the following paragraph and identify the disease.
Today, her child became one and half year old. However, that child does not seem to be healthy and happy. It was continuously crying and gradually becoming weak. It has shortness of breath. Its nails have become blue.
From the above mentioned symptoms, it seams like the child is suffering from some kind of respiratory disorder/circulatory disorder. He has problem in breathing and his nails have become blue which means there is low level or lack of oxygen circulating in the red blood cells. It is known as cyanosis.
It occurs when enough oxygen is not present in blood, thus making the skin or membrane below the skin turn purplish-blue.