Italy’s large elderly population poses a challenge in slowing the number of coronavirus deaths in the worst-affected country in Europe, a health specialist has said.

The virus has killed 79 people in Italy, overwhelmingly aged between 63 and 95 with underlying serious illnesses.

The youngest patient to die was 55 and suffering from chronic disease. A 61-year-old doctor who was not known to have underlying health problems has also died.

Quick guide What are coronavirus symptoms and should I go to a doctor? Show Hide What is Covid-19? Covid-19 is caused by a member of the coronavirus family that has never been encountered before. Like other coronaviruses, it has come from animals. The World Health Organization (WHO) has declared it a pandemic. What are the symptoms this coronavirus causes? According to the WHO, the most common symptoms of Covid-19 are fever, tiredness and a dry cough. Some patients may also have a runny nose, sore throat, nasal congestion and aches and pains or diarrhoea. Some people report losing their sense of taste and/or smell. About 80% of people who get Covid-19 experience a mild case – about as serious as a regular cold – and recover without needing any special treatment. About one in six people, the WHO says, become seriously ill. The elderly and people with underlying medical problems like high blood pressure, heart problems or diabetes, or chronic respiratory conditions, are at a greater risk of serious illness from Covid-19. In the UK, the National health Service (NHS) has identified the specific symptoms to look for as experiencing either: a high temperature - you feel hot to touch on your chest or back

a new continuous cough - this means you’ve started coughing repeatedly As this is viral pneumonia, antibiotics are of no use. The antiviral drugs we have against flu will not work, and there is currently no vaccine. Recovery depends on the strength of the immune system. Should I go to the doctor if I have a cough? Medical advice varies around the world - with many countries imposing travel bans and lockdowns to try and prevent the spread of the virus. In many place people are being told to stay at home rather than visit a doctor of hospital in person. Check with your local authorities. In the UK, NHS advice is that anyone with symptoms should stay at home for at least 7 days. If you live with other people, they should stay at home for at least 14 days, to avoid spreading the infection outside the home.

The death toll, provided by officials on Tuesday night, marked an increase of 27 in 24 hours. Twenty-three per cent of the Italian population is over 65, making it the oldest in the world after Japan.

“Italy is a country of old people,” said Prof Massimo Galli, the director of infectious diseases at Sacco hospital in Milan. “The elderly with previous pathologies are notoriously numerous here. I think this could explain why we are seeing more serious cases of coronavirus here, which I repeat, in the vast majority of cases start mildly and cause few problems, especially in young people and certainly in children.

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“Our life expectancy is among the highest in the world. But unfortunately, in a situation like this, old people are more at risk of a serious outcome.”

The are more than 2,500 people infected in Italy. Health workers have carried out 25,856 swab tests, significantly dwarfing the number undertaken in other European countries.

Those tested include Pope Francis, 83, after he was forced to cancel engagements this week because of a cold. He returned a negative result, Il Messaggero newspaper reported on Tuesday.

The majority of cases – 1,520 – are in the northern Lombardy region, where 10 towns have been under lockdown for more than a week. The virus has spread to more than half of Italy’s 20 regions, including Tuscany, Puglia, Sicily and recently Sardinia.

Authorities say the majority of people who tested positive in other regions were travelling from Lombardy or had been in the north for a few weeks before the outbreak.

Facebook Twitter Pinterest Prof Massimo Galli. Photograph: Miguel Medina/AFP via Getty Images

Of those infected, 1034 are in hospital – 229 in intensive care – and 1,229 are recovering at home. The number of people who have recovered from the illness has more than doubled to 160.

Researchers at Sacco hospital last week isolated a strain of the virus from an Italian patient, which suggests Covid-19 may have circulated in northern Italy for weeks before it was detected.

Galli said: “It has been claimed that the so-called Italian virus is very different from the Chinese one. These are simply rumours. We are currently mapping out the sequences and only afterwards can we know.

“Obviously, since it is an RNA virus, it is expected to be at least a little different from the Chinese one. RNA viruses typically change: between each viral copy and its template there will be a few differences, like a single nucleic acid mutation. But only once we have the sequences can we begin to make comparisons.”

Italy had experienced the coronavirus outbreak despite being one of the first countries that not only closed contact with Wuhan but also all air contact with China, he said.

“Some countries have accused us of taking too drastic measures. Yet even taking drastic measures, proactively, does not seem to have been enough,” Galli said. “What is certain is that we had no way of predicting the outbreak in the so-called red zone or identifying it before sick people appeared.”

Many people could reach Italy from other countries that had not closed direct flights from China, Galli said, adding that “outbreaks that will eventually appear elsewhere in Europe” may not necessarily come from Italy.

“Let us remember the case of a person who had travelled from Singapore, of British nationality, who then went to visit friends in France and infected them,” he said. “If such a thing happened in other parts of Europe, it means we might end up with other red zones.”

A doctor in Italy who is recovering from the virus at home told the Guardian she had only mild symptoms. She lives with her parents and brother, all of whom tested negative. She will be tested again on Friday, after two weeks in quarantine.

“In the majority of cases, people heal,” said the doctor, who asked not to be named. “The problem is we don’t have the mechanisms to protect those who are most vulnerable: the elderly or those with serious health problems. But we need to be objective – an increase in new cases doesn’t mean an increase in serious cases.”