They're the most common cause of stomach bugs (gastroenteritis) in the UK. Each year, it's estimated that between 600,000 and 1 million people in the UK catch norovirus. The illness is sometimes called the winter vomiting bug because it's more common in winter. However, you can catch the virus at any time of the year.hey're the most common cause of stomach bugs (gastroenteritis) in the UK. Each year, it's estimated that between 600,000 and 1 million people in the UK catch norovirus. The illness is sometimes called the winter vomiting bug because it's more common in winter. However, you can catch the virus at any time of the year.
On the contrary, individuals who are carriers for the sickle cell disease (with one sickle gene and one normal hemoglobin gene, also known as sickle cell trait) have some protective advantage against malaria.
Why is Malaria Dangerous? How does Malaria become so dangerous? Malaria in humans can be caused by a number of different parasites â the most dangerous, and the one which is responsible for over 90% of the worldwide deaths from malaria, is Plasmodium falciparum. The reason that P. falciparum is so dangerous is because it affects the behaviour of red blood cells.