A partner at top Austrian law firm Wolf Theiss and another at a New York trust and estates boutique have been hospitalised by the coronavirus.

At Wolf Theiss, three more employees tested positive to Covid-19 after the firm resolved to test all staff on learning of the partner’s illness.

Both the Wolf Theiss partner and the New York lawyer are reported to be in critical conditions by local media.

In a statement issued on 3 March, Wolf Theiss said it had set up a ‘crisis team’ after learning last Thursday that one of its partners had the virus.

Working with the relevant authorities, it set up a medical hotline and began testing staff.

“The virus test started within 24 hours after our partner's illness became known,” the firm said. “We did it on our own initiative and at our own expense to gain certainty. The test was carried out by a German virological institute.”

The firm said more than 200 employees had tested negative, with those awaiting their results working from home to “avoid contact with employees, clients and courts until the results are available”.

At the time of the statement, the three staff who had tested positive were “undergoing an official confirmation test” while self-isolating themselves at home. They had displayed no symptoms.

“Due to the immediate, continuous testing of our employees,” the statement said, “Wolf Theiss is currently the only Austrian company to ensure that client, court and employee contacts are only made through negatively tested employees.”

The New York lawyer, widely reported to be from the trust and estates boutique Lewis and Garbuz, is one of two know cases in New York out of a national tally that stands at 126 across 13 states.

Law firms have instituted an array of measures to protect staff from the virus while continuing to conduct business.

Last week, Baker McKenzie closed its London office due to a potential case – it has now reopened – while Linklaters is among many firms asking staff returning from affected zones to work from home for 14 days.

Latham & Watkins cancelled its global partners meeting, which was due to take place in New York this week.