The patients were aged between 70 and 98 and being cared for at Queen Alexandra Hospital. All had underlying health conditions.
It brings the total to five deaths in the city after a 59-year-old woman with underlying health conditions died at the hospital in Cosham on Tuesday after testing positive for Covid-19.
Portsmouth Hospitals NHS medical director Dr John Knighton said: ‘Sadly, we can confirm that four patients who were being cared for at Queen Alexandra Hospital and had COVID-19, have died.
‘The patients, two women, aged 89 and 98, and two men, aged 70 and 90, all had underlying health conditions.
‘We have informed the families of the patients and our thoughts and condolences are with them at this difficult and distressing time.’
As of 9am yesterday (March 19) Public Health England confirmed Portsmouth has five cases of Covid-19.
The total for Hampshire has risen to 87 and there are seven cases in Southampton.
There are 3,269 cases across the UK and 144 deaths.
PHE also reported that 79 patients had recovered.
Coronavirus: the facts
What is coronavirus?
Covid-19 is a respiratory illness that can affect lungs and airways. It is caused by a virus called coronavirus.
What caused coronavirus?
The outbreak started in Wuhan in China in December 2019 and it is thought that the virus, like others of its kind, has come from animals.
How is it spread?
As this is such a new illness, experts still aren’t sure how it is spread. But similar viruses are spread in cough droplets. Therefore covering your nose and mouth when sneezing and coughing, and disposing of used tissues straight away is advised. Viruses like coronavirus cannot live outside the body for very long.
What are the symptoms?
The NHS states that the symptoms are: a dry cough, high temperature and shortness of breath - but these symptoms do not necessarily mean you have the illness. Look out for flu-like symptoms, such as aches and pains, nasal congestion, runny nose and a sore throat. It’s important to remember that some people may become infected but won’t develop any symptoms or feel unwell.
What precautions can be taken?
Washing your hands with soap and water thoroughly. The NHS also advises to cover your mouth and nose with a tissue or your sleeve (not your hands) when you cough or sneeze; put used tissues in the bin immediately and try to avoid close contact with people who are unwell. Also avoiding touching eyes, nose and mouth unless your hands are clean.
Sources: World Health Organisation and NHS