“As we mark this sombre moment, WHO reminds all countries and communities that the spread of this virus can be significantly slowed or even reversed through the implementation of robust containment and control activities,” the UN health agency said in a statement.

It said China and other countries are showing that spread of the virus can be slowed and its impact reduced through the use of universally applicable actions.

Coronavirus was first reported in China’s Wuhan and has since been detected in dozens of countries, affecting communities and global economy.

The virus has killed more than 3,400 people and emerged in more than 90 countries but more than half of those who contracted the virus have now recovered. It is retreating in China and in nearby South Korea.

“Every effort to contain the virus and slow the spread saves lives,” the UN health agency said, noting that these efforts give health systems and all of society much needed time to prepare, and researchers more time to identify effective treatments and develop vaccines.

WHO said everyone should work together to stop, contain, control, delay and reduce the impact of this virus at every opportunity.

“Every person has the capacity to contribute, to protect themselves, to protect others, whether in the home, the community, the health care system, the work place or the transport system,” the statement said.

The 100,000 figure of global infections is largely symbolic, but dwarfs other major outbreaks in recent decades, such as SARS, MERS and Ebola.

Coroanvirus is still much less widespread than annual flu epidemics, which result in up to five million annual severe cases around the world and from 290,000 to 650,000 deaths annually, according to WHO.