Paramedics are being overwhelmed by calls about bats and non-existent at-home coronavirus testing, and jeopardising response times for critical patients, as the frontline responders prepare for rising numbers of serious COVID-19 cases.

The state’s chief paramedic has issued a plea to the public to only dial triple zero in an emergency, warning ambulances would be under "immense pressure" to reach the mostly life-threatening cases in the midst of a widespread coronavirus outbreak.

'We need people to call triple zero for emergencies only': Chief executive of NSW Ambulance Dominic Morgan. Credit:Peter Braig

NSW Ambulance call centre staff were inundated by more than 200 calls an hour on Friday night - almost 3400 calls over a 24-hour period - busier than New Year's Eve.

Many were callers frightened and anxious about the virus and the radical government restrictions aimed at containing it, as the number of cases surpassed 1000 on Wednesday.