Its interesting to note they did not mention antibiotics as something that was being tested. I know for a fact that a major bay area hospital is treating covid-19 patients with a course of antibiotics(unsure which type), which is strange as its a virus. The nurse I know said they are seeing good results, the antibiotics are administered right away(they didn't say if anything else is administered) and 5 of 6 patients are being sent home with none coming back with worse symptoms. The sample size is small, maybe 30-40 and I wonder if these patients are already healthy enough that the virus is not affecting them greatly. It looks like other countries are looking into it as well:
It is almost certainly azithromycin. Interestingly, it's antiviral effects have be previously studied. However, people aren't really happy with the lack of error bars on that (French Study) chart or the small sample size. Studies are double blind for a reason.
... and most anything that Derek Lowe has to say about small molecule drugs. He's apparently had a bit of time at home recently to blog more, and is rather focused currently on Corona virus.
One theory I've heard is that it is not the virus itself that kills you, but your immune system overreaction causing secondary damage which leads to infections. So the antibiotic might be aimed at that part? Just a guess.
If that is true (it is theorised that was how the 1918 flu killed people) it would primarily kill people with strong immune systems, not people with weak immune systems. I saw an epidemiology specialist (Michael T. osterholm maybe?) say that luckily this isn't how COVID-19 behaves or we would see millions dead.
They are probably put on antibiotics when they are intubated, to prevent:
Ventilator-associated pneumonia (VAP) is a type of lung infection that occurs in people who are on mechanical ventilation breathing machines in hospitals. ... Between 8 and 28% of patients receiving mechanical ventilation are affected by VAP
https://techcrunch.com/2020/03/19/french-study-finds-anti-ma...