Wikipedia has become one of the world's most powerful portals of information - so powerful, in fact, that it can even show us when people are ill.

Researchers at Boston Children's Hospital have found that monitoring the site's traffic, which exceeds 500 million visitors a month, can indicate how many people have simply caught the flu.

In the PLOS Computational Biology journal, published on 17 April, David McIver and John Brownstein have developed a model analysing the amount of traffic on influenza-related Wikipedia articles in real-time to estimate flu levels in the American population.

McIver and Brownstein said this method produced information two weeks sooner than data released from the Centers for Disease Control and Prevention, and 17% quicker than Google Flu Trends data.

In a joint statement they said: "Each influenza season provides new challenges and uncertainties to both the public as well as the public health community. We're hoping that with this new method of influenza monitoring, we can harness publicly available data to help people get accurate, near-realtime information about the level of disease burden in the population."

They calculated the number of times certain Wikipedia articles were accessed every day from December 2007 to August 2013. The model they developed performed well through influenza seasons and through events such as the H1N1 pandemic in 2009, which received high levels of media attention.

According to its research Wikipedia has 30 million articles available, with an additional 17,800 published a day. It receives 506 million visitors per month, representing 27 billion page views since its launch in 2001.

Influenza claims between 3,000 to 50,000 lives each year in the United States despite being avoidable through vaccination.