Fucoidan inhibiting norovirus
Noroviruses belong to the calicivirus family and include strains of virus that can affect both humans and animals.
Norovirus infections are a leading cause of epidemic and sporadic gastroenteritis worldwide. To provide some perspective, in the United States norovirus is estimated to cause 19-21 million episodes of gastroenteritis, 1.7 – 1.9 million medical outpatient visits, 400,000 emergency department visits, 56,000 – 71,000 hospitalizations, and 570 – 800 deaths annually. The total annual healthcare and social costs for norovirus disease in the USA have been estimated at US$5.5 billion.
Gastroenteritis caused by norovirus usually starts suddenly and causes vomiting and watery diarrhoea. Sufferers may also experience nausea, fever, stomach pains, headache, muscle aches and dehydration. Symptoms usually begin between 24 and 48 hours after exposure to the virus and generally last for one or two days. It is highly contagious and quickly spreads in day care centres, schools and other institutional settings.
There are currently no preventative vaccines or antiviral treatments.
Research has shown that fucoidan is an inhibitor of noroviral entry to cells. A number of pre-clinical studies indicate the potential for fucoidan to both lessen the symptoms of norovirus and reduce the spread of infection. A recent Korean study has also shown dose dependent viral titre reduction of murine norovirus and feline calicivirus in vitro along with binding of P domains in human norovirus.
In the near future we can expect to see increasing research into this fucoidan application. It has the potential to address both the symptoms and spread of this unpleasant virus.