The UK and US have issued a joint warning cyber-spies are targeting the health sector.
Hackers linked to foreign states have been hunting for information, including Covid-19 data and vaccine research, they say.
UK sources say they have seen extensive activity but do not believe there has been any data theft so far.
Those behind the activity are not named in the alert but are thought to include China, Russia and Iran.
The three countries have all seen major outbreaks of the virus but have denied previous claims of involvement in such activity.
The joint advisory says the UK and US are currently investigating a number of incidents in which other states are targeting pharmaceutical companies, medical-research organisations, and universities, looking for intelligence and sensitive data, including research on the virus.
Understanding how other countries are dealing with the Covid-19 crisis and progress in research has become a high priority for intelligence agencies around the world.
In a crisis, every state will want to use its intelligence capability to better inform itself.
And in a locked-down world, cyber-espionage is more practical than traditional human espionage, making it another field where an existing trend towards online working may be accelerated.
Analysts say they are seeing a particular rise in aggressive operations from a range of states at the moment.
And this has meant organisations that might not have considered themselves to be top targets for hackers from foreign states are now in their sights.