Fighting the new coronavirus has been a battle against the unknown for doctors.
How does it attack the body? What are the full range of symptoms? Who is more likely to be seriously ill or die? How do you treat it?
Now, an account by medics on the front line of this epidemic, at the Jinyintan Hospital, in Wuhan, is starting to provide answers.
A detailed analysis of the first 99 patients treated there has been published in the Lancet medical journal.
All of the 99 patients taken to the hospital had pneumonia – their lungs were inflamed and the tiny sacs where oxygen moves from the air to the blood were filling with water.
The second patient, a 69-year-old man, also had acute respiratory distress syndrome.
He was attached to an artificial lung or ECMO (extra-corporeal membrane oxygenation) machine but this wasn’t enough.
He died of severe pneumonia and septic shock when his blood pressure collapsed.
At least 10% die
As of 25 January, of the 99 patients:
57 were still in hospital 31 had been discharged 11 had died
This does not mean the death rate of the disease is 11%, though, as some of those still in hospital may yet die and many others have such mild symptoms they do not end up in hospital.
Live animals sold at the Huanan seafood market are thought to be the source of the infection, called 2019-nCoV.
And 49 out of the 99 patients had a direct connection to the market:
47 worked there, either as managers or manning the stalls two were shoppers who had only popped in
Middle-aged men worst affected
Most of the 99 patients were middle-aged, with an average age of 56 – and 67 of them were men.
However, more recent figures suggest a more even gender split. The China Centers for Disease Control and Prevention said 1.2 men were infected for every 1.0 women.
There are two possible explanations for the difference:
Men could be more likely to become severely ill and need hospital treatment Men, for social or cultural reasons, may have been more likely to be exposed to the virus at the beginning of the outbreak
Dr Li Zhang, at the hospital, says: “The reduced susceptibility of females to viral infections could be attributed to the protection from X chromosome and sex hormones, which play an important role in immunity.”
And those who were already sick
Most of the 99 had other diseases that may have made them more vulnerable to the virus as a “result of the weaker immune functions of these patients”:
40 had a weak heart or damaged blood vessels due to conditions including heart disease, heart failure and stroke A further 12 patients had diabetes
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Learn more about the new virus
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