There was hardly any warning in Patrick's case. He was unsettled one night - unusual for an infant who since birth had been a sound sleeper - but seemed fine the following morning when we left him with our nanny, Sandra. Maybe it is imagination embellished by hindsight, but when I try now to recall how he looked that morning, I see a look of dread in his eyes, as though he already knew something horrible was happening to his small body.
The meningococcal bacteria had probably been in his system for a few days by then, more than likely contracted over the Christmas period from any of the people who had kissed him or cuddled him. One of the most disturbing aspects of the illness is its randomness; millions of people carry the meningococcal germ with no effect. Doctors are still unsure as to why it affects the small number of people - around 2,000 - who succumb to it every year.
By the middle of the afternoon, Patrick was ill enough for Sandra to be worried. He was vomiting, floppy and drowsy, but there were none of the classic symptoms, such as red blotches on his torso. No "glass test" would have worked here.
Sandra brought him to our GP, who did not diagnose meningitis but said that he was sick enough to warrant immediate hospital attention. He advised Sandra to take him to St Mary's Paddington, our nearest big hospital, just a mile from where we live in west London. This accident of geography saved his life.
As when trying to recollect the run-up of events to a serious road accident, I have only selective memory of the next few hours: a phone call from my wife, hurried departure from the office (remarking: "You always worry about meningitis, don't you?"), a car trip with Emma across London with panic levels rising. Then the blurred events at St Mary's. Sandra crying, Patrick's body already being injected and hooked up to lines and drips, doctors and nurses rushing around in what looked like chaos.
The disease had already sent our baby's body into toxic shock, and all his vital organs - kidneys, liver, heart - were under attack. He was virtually unconscious, but occasionally would open his eyes for a few seconds, showing the same, literally dreadful expression I had seen that morning. That was the last time we saw his eyes open for three weeks.
For the next few days, Patrick was on the brink of death. We were not told so at the time - the medics would not have used such melodramatic language - but later we learnt that on eight occasions in the first three days, they feared they had lost him.
His baptism - originally set for St Patrick's Day the coming spring - took place on the evening of the second day, with a crowd of sobbing relatives and friends squeezed between the blinking, bleeping screens and the metres of tubing surrounding his bed.
Our anchor during this time was Parviz Habibi, the senior consultant at St Mary's, who has made a lifetime's work of trying to conquer meningitis. The fact that Patrick landed in Habibi's care so quickly meant that he would live through the initial onslaught of the disease. Habibi explained - with frankness when appropriate, but always with sensitivity - that although the bacteria had been killed by the huge doses of antibiotic our son had received, he was now entering the most critical phase of the illness.
As it dies, the meningococcal germ releases deadly toxins, which have horrible side-effects. For Patrick the most noticeable was that his blood vessels began to leak fluid into his body tissues, with grotesque results. An infant who had previously weighed 9kg ballooned to four times that; his skin stretched and split; his testicles grew to the size of a grapefruit. The pain of seeing our baby son in this condition will never leave me.
There were also changes to his limbs. The disease weakens the heart and makes it less able to push blood around the body. Patrick's fingers and toes went dark purple, then began to scab over in a hard, black covering. The consultants warned us that he might lose the tips of his fingers and toes.
And all the time there was the prospect of brain damage. With the massive haemorrhaging Patrick had experienced, it was possible that he would be left deaf, blind or mute, or in a vegetable state, if he survived. He was too sick to undergo a brain scan, so for the first three weeks we could only pray this was not so.
Emma had been a tower of strength throughout, promising Patrick's unconscious body early on that she would not go home until he could. (She kept the promise.) Her reaction to the horror was to try to master the medical argot and the sophisticated machinery keeping Patrick alive. But both she and I dissolved in tears as he was taken from intensive care to be scanned, knowing that in a few hours we might find we were parents of a baby boy who was both mentally and physically handicapped. When the scan results came through, showing no signs of significant brain damage, it was the first time we had smiled for three weeks.
After that, good news began to come more frequently. One evening in February, our five-year-old daughter Rosie paid her daily visit. She had been badly affected by the whole trauma. She had refused to go near Patrick's bed, believing she, too, would catch the germ, and later seemed reluctant to stay with him.
But this evening she obviously decided that it had gone far enough. She strode into intensive care with all her five-year-old determination and shouted - as she used to do at home to her baby brother - "wakey wakey, Patrick". Our son, who had shown no flicker of life for nearly a month apart from machine readings, slowly opened one eye in recognition of her voice.
Soon afterwards, the doctors decided that, though still unconscious, Patrick was well enough to be lifted from his bed. I shall never forget holding him in my arms for the first time in weeks. Despite the tubes and bandaging, it was as though he had just been delivered again and I was hugging my newborn son.
But there were awful times still to come. To cope with the terrible pain he had been experiencing, Patrick had been on high doses of morphine, and had become dependent. Now he had to come off the drug. It is terrible to watch helplessly as your blameless infant goes through the fevered spasms of "cold turkey", retching and crying.
Once morphine withdrawal had been established, Patrick, who was now much more awake, could be transferred from intensive care to a high-dependency ward, but this was the start of the most distressing stage of the whole illness.
We were resigned to the fact that he might lose finger tips and toes, but it became obvious that it was worse than that. The blackening had spread, so that now most of his left hand was affected, with withered black talons hanging where there had once been perfectly formed baby fingers. His right hand was better, with the blackening extending just below midway on each finger.
The real worry was his right foot, which was completely black and hard as shell. By some apparently random process, his left leg, which had been as bad as the right, had returned to normal.
The specialists told us that there was no alternative to amputation, and so began a series of increasingly harrowing operations. Emma and I knew that, each time he went to theatre, he would lose another piece of what just a few months before had been born a perfect human body. I cannot drive from my mind the image of him waking distraught in the post-op recovery room with another bandaged stump hanging from him.
Patrick came home in March, a few days before his first birthday, which became a celebration of his bravery and a thanksgiving for his return from the edge of death. He is now walking, with a prosthetic leg, and making good use of the limited digits he has on his right hand. Barring major advances in medicine, he will never be able to use his left as a normal hand.
He is behaving exactly like any normal toddler - loving and lovable, mischievous, exasperating and sleep-depriving. I have no doubt that he will lead a full and happy life, especially as he was so young when it happened to him.
But meningitis has robbed us of the dreams we had for Patrick. He may have problems at school with friends, and later on with girls. He will never be a footballer, or a classical guitarist. We, and all the people who supported him when he was sick, will love him all the more for his courage in fighting the illness, and for the simple fact that he is still alive. But his life will not be easy.
There were times - when I saw him with other children - when I would inwardly curse God and the world and think: "Why him? Why us?" A post- traumatic stress counsellor told me that this was a normal reaction, but that I should take care it did not become excessive self-pity. So instead I curse the meningococcal bacteria, and will continue to do so every day of my life.
Frank Kane is news editor of `Sunday Business'Reuse content