In the past few months, schools in the United States have closed because of epidemics of norovirus. Commonly referred to as stomach flu, norovirus infections cause watery diarrhea, low-grade fever, and projectile vomiting, which is an incredibly efficient way to share the virus.
Norovirus is infectious and spreads quickly in an enclosed population, such as at a school. Even though most people recover after 24 to 48 hours, the virus is a main cause of childhood diseases, and in developed countries produces about 50,000 child deaths per year.
However, not everyone is vulnerable to norovirus, and whether one is affected or not may depend on their blood type.
Tendency to Getting Norovirus Depends on Blood Type
When the virus is consumed, it originally infects the cells that order the small intestine. Scientists are not entirely sure how exactly this condition then causes the manifestations of the disease. However, an interesting aspect of norovirus is the fact that, after exposure, it is mainly the blood type that decides whether a person gets sick.
Your blood type, be it A, B, AB, or O, is managed by genes that decide which types of molecules, known as oligosaccharides, are detected on the surface of your red blood cells. Oligosaccharides are formed out of various kinds of sugars, all connected in intricate ways.
The same molecules on red blood cells are seen on the surface of cells that border the small intestine. Norovirus and a small number of other viruses utilize these oligosaccharides to implement themselves and infect the intestinal cells. It is the particular form of these oligosaccharides that decides whether a specific strain of the virus is able to attach and infect the cells.
The presence of only one oligosaccharide, also known as H1-antigen, is needed for attachment by numerous norovirus strains. People who do not create H1-antigen in their intestinal cells are mainly approximately 20 percent of the European-originated population and are immune to numerous strains of norovirus.
More sugars can be annexed to the H1-antigen to produce the A, B, or AB blood types. People who are not able to make A and B alterations have the O blood type.
Immunity to Norovirus is Temporary
A norovirus infection caused an incredibly powerful immune response that removed the virus in a few days. Even so, the response seems to be temporary. The majority of research has discovered that immunity protecting against reinfection with the same virus strain persists less than six months.
In addition, infection with one strain of the virus provides almost no defense against infection from another. Therefore, you can have repeated encounters with norovirus. The variety of the virus strains and the volatility of the immune reaction makes the development of an efficient treatment more difficult. At the moment, clinical trials are testing the impacts of vaccines made out of capsid proteins of the two most common norovirus strains.
Overall, these test vaccines offer some good immune reactions; however, the longevity of the immune reaction is now being analyzed. The next stage of clinical trials will examine whether the vaccines actually prevent or decrease the symptoms of norovirus infection.