Mr Fisher grew up in the East End of London. All his family were talented singers and he made his debut in the Yiddish theatre in Whitechapel at the age of 11. He later conducted the London Jewish Male Choir, with whom he made a number of records. There were hopes that he might become a rabbi, but he became a teacher instead.
The army trained Mr Fisher to be a radiographer in the Medical Corps. Photographs of the youthful Private show him to have been an extremely good-looking young man - his eyes are still very blue and sparky - and his fellow soldiers look rather puny beside him. His unit - 32 Casualty Clearing Station (CCS), the Second World War equivalent of M*A*S*H - was a crack division, chosen to be the first CCS in Normandy on D-Day.
In his diary, he describes how they then spent months "idling" in Holland, before being suddenly sent to Germany. "We were happy," he wrote, "thrilled at last at the prospect of going into active service again." Instead, they were dispatched to Belsen, in north-west Germany, where 10,000 corpses lay unburied and 60,000 people were in need of urgent medical attention. The experience, he says, scarred him for life.
His Belsen diary is now part of an archive at the Imperial War Museum, and Index on Censorship, the journal that campaigns for freedom of speech, has just published an excerpt, along with other contemporary accounts, in its special issue, "Gagging For It", marking the 50th anniversary of the United Nations Declaration of Human Rights.
It is a remarkable document, not least because Fisher was the only Jew in his unit, and yet he makes just one oblique reference to the fact in his diary, when he describes giving a sweet to a young girl: "a co-religionist - as were most of these wretched people."
"I spoke, I suppose, as I always speak," he says, "as a humanitarian, not as one sect. When I was writing, I wasn't concerned with myself, I was writing about them."
The Germans had not originally intended Belsen to be an extermination camp. It was established in 1943 to house Jews who were to be exchanged for Germans interned in the UK and US. Within a year, it had become a dumping ground for Jews from other camps. Tens of thousands died from disease, neglect and starvation - among them Anne Frank. When the British entered the camp on 15 April 1945 after negotiating a truce, a typhus epidemic was raging.
"The women had their heads shaved, skinny isn't the word for them," remembers Mr Fisher. "One of the main priorities was delousing them. I saw armies of lice on beds, armies like soldiers, columns for them on bed linen. There was a horrific scene in the first days of looking after these people. There was a little anteroom in a delousing centre and a nurse had this survivor lying on her back and she was washing her. And the poor survivor was so emaciated that where her tummy was, you saw this tremendous concave indentation. The nurse had to scoop the water out with a big scoop. There was nothing there, just this enormous, deep, deep cavity."
He still dreams about the wagon in which he used to develop X-rays, "It was a tremendous thrill developing the film, I used to say, 'Manny, you're the first man to see this'." He says that his dreams are sometimes more vivid than his waking life.
There was little call for his skills as a radiographer at Belsen. "I was nurse and mother and father there," he says. Aged 24, he was put in charge of between 150 and 200 patients, the maximum usually tended at one time by the entire CCS. Within eight days, 6,000 patients were brought to the unit for treatment in army barracks outside the camp.
In one of the most shocking extracts from his diary, he describes how a number of naked patients rioted for food and attacked one of the nurses. Many had died from overfeeding when the camp was first liberated and a strictly controlled diet had to be administered.
He does not recall having any knowledge of the Nazis' Final Solution before arriving at Belsen and tells a chilling story which illustrates the ignorance of his unit. "When we got to the camp, the Sergeant said, 'Here, boys, help yourselves, there are a lot of watches here.' I'm ashamed - I don't know whether I took a watch but it didn't occur to me, we didn't know. We just thought it was booty that had been left lying around. Everybody grabbed watches. Dear God."
He wrote his diary in his tent by the light of a candle stub "at the end of a long filthy day". His unit was not supposed to go into the camp itself because of the typhus, but he used to sneak in with a mate. "The whole thing was just like a bad dream," he wrote. "I almost pinched myself to make sure that I was awake. The scene was more like a Hollywood representation of a concentration camp than the real thing. It was too unbelievable to believe. I was stunned."
Mr Fisher was also much in demand as an interpreter. He speaks German, French and Yiddish, among other languages. As a child, he showed a great talent for Hebrew and at the age of 10 he was teaching other boys their barmitzvah readings. His fellow soldiers called him "Shakey" (Shakespeare) in recognition of his education.
He came home on leave from Belsen in time for VE day. "I can remember vividly being on a bus going to Trafalgar Square and at that time they were showing the newsreels in the cinemas about Belsen and I heard a couple of old lags, for want of a better word, saying. 'Oh, did you see that stuff in the news about the camp? Don't believe it, it's a lot of propaganda.'
"I couldn't join in the celebrations, I felt utterly dejected. Everybody was cheering like mad and I just felt miserable. You know, you get a different view when you come from something like that."
The army gave Mr Fisher's unit 10 weeks' holiday in Denmark in recognition of its work at Belsen, a time which he remembers with great affection. After the war he married and had four children. He believes it is vital to talk about his Belsen experiences. "It's too horrific for people to actually picture and their memories are short. The beginnings of it are happening again with the rise of neo-Nazi groups and man's general inhumanity to man."
Index on Censorship 3/98, Gagging For It, pounds 8.99. Available from bookshops, or telephone 0171-278 2313.Reuse content