New York, June 2 (IANS): The world had come to know of the deadly Ebola outbreak in West Africa last year much before the official announcement thanks to Twitter, a new study says.

Tweets regarding the Ebola outbreak had reached more than 60 million people in three days prior to official announcements of the outbreak, as per the study.

"It's clear that Twitter is a useful resource for spreading breaking health news in these West African countries," said the researchers from Columbia University in New York.

The researchers analysed over 42,000 Ebola-related tweets posted to the social networking site between July 24 and August 1, 2014, medicalxpress.com reported.

This was the week when Nigeria reported the first case of Ebola, Sierra Leone declared a national state of emergency and the first American was diagnosed with Ebola.

Twitter was a resource for those to share news of Ebola cases prior to official announcements from the Nigerian ministry of health, the World Health Organisation and the Centres for Disease Control and Prevention.

During the three days prior to an official announcement from the Nigerian ministry of health nearly 1,500 tweets were disseminated regarding Ebola.

"The results of this analysis indicate how Twitter can be used to support early warning systems in outbreak surveillance efforts in settings where surveillance systems are not optimal," the researchers observed.

The analysis of the content of tweets revealed that the main topics of concern in the tweets were Ebola risk factors, prevention education and health information, spread and location of Ebola and compassion for countries in Africa.

The study was published in the American Journal of Infection Control.