By NewsGram Staff Writer

The World Health Organisation (WHO) today declared Liberia free of Ebola virus transmission after no new cases were reported in the country during the last 42 days.

"Forty-two days have passed since the last laboratory-confirmed case was buried on 28 March 2015. The outbreak of Ebola virus disease in Liberia is over, " WHOO said in a statement.

Liberia's last case was a woman in the greater Monrovia area who developed symptoms on 20 March and died on 27 March. The source of her infection remains under investigation. The 332 people who may have been exposed to the patient were identified and closely monitored. No one developed symptoms; all have been released from surveillance.

Health officials have maintained a high level of vigilance for new cases. During April, the country's five dedicated Ebola laboratories tested around 300 samples every week. All test results were negative.

While WHO is confident that Liberia has interrupted transmission, outbreaks persist in neighbouring Guinea and Sierra Leone, creating a high risk that infected people may cross into Liberia over the region's exceptionally porous borders.

Interruption of transmission is a monumental achievement for a country that reported the highest number of deaths in the largest, longest, and most complex outbreak since Ebola first emerged in 1976. At the peak of transmission, which occurred during August and September 2014, the country was reporting from 300 to 400 new cases every week.

During those 2 months, the capital city Monrovia was the setting for some of the most tragic scenes from West Africa's outbreak: gates locked at overflowing treatment centres, patients dying on the hospital grounds, and bodies that were sometimes not collected for days.

Flights were cancelled. Fuel and food ran low. Schools, businesses, borders, markets, and most health facilities were closed. Fear and uncertainty about the future, for families, communities, and the country and its economy, dominated the national mood.

Though the capital city was hardest hit, every one of Liberia's 15 counties eventually reported cases. At one point, virtually no treatment beds for Ebola patients were available anywhere in the country. With infectious cases and corpses remaining in homes and communities, almost guaranteeing further infections, some expressed concern that the virus might become endemic in Liberia, adding another – and especially severe – permanent threat to health.