As a gastroenterologist I am asked almost daily about Covid-19 and any precautions patients should take if they are on medications that decrease immunity. We call them immunomodulators or biologics.

The clinical presentation of Covid-19 can range from mild, non-specific respiratory symptoms to severe organ dysfunction — such as acute respiratory distress syndrome — that can lead to death.

Most cases are mild, with the common symptoms being fever (83 per cent to 98 per cent), cough (46 per cent to 82 per cent), muscular pain or fatigue (11 per cent to 44 per cent), and shortness of breath (31 per cent).

As you probably know by now, risk factors for more severe illness requiring hospitalisation appear to be advanced age and underlying chronic conditions such as diabetes, lung disease and cardiovascular disease.

Some reports suggest that in more severe cases, the median time from first symptom onset to the development of shortness of breath and/or need for hospitalisation is five to eight days.

The incubation period appears to average 5.2 days but may range from two to 14 days, and potential asymptomatic infection has been reported.

Patients may complain of gastrointestinal symptoms such as nausea or diarrhoea. In the previous coronavirus outbreak, diarrhoea was reported in up to 25 per cent of patients. The reported frequency of diarrhoea among Covid-19 patients at the moment has varied from 2 per cent to 33 per cent and was one of the prominent symptoms reported by the first case in the United States

The virus has been detected in patients’ stools. So while Covid-19 appears to spread primarily through respiratory droplets and secretions, the gastrointestinal tract may be another potential route of infection.

There are no specific recommendations for people on immunosuppression, such as inflammatory bowel disease patients and those with Crohn’s and ulcerative colitis. IBD research has found that viral infections are more likely among patients on immunomodulators, such as 6-mercaptopurine and azathioprine, than those on biologics, but it remains unclear if this can be extended to Covid-19.

Currently, we don’t advise IBD patients — or indeed others on immunosuppression, such as those with autoimmune hepatitis, etc — to hold or stop medications. The risk of disease flare far outweighs the chance of contracting Covid-19.

In essence, stick to your current therapy as we really want to limit steroid use for flare in this Covid-19 world.

However, if an IBD patient has symptomatic Covid, the next biologic infusion should be postponed until they are better.

What are the possible outcomes for patients infected by Covid?

1, Remaining asymptomatic with increased immunity

2, Clearing the virus in some other way, but without sustained immunity (while this is unclear, it is possible)

3, Developing Covid (defined as symptoms, fever, radiographic abnormalities on chest imaging, lymphocytosis or lymphopenia, etc) and recovering completely

4, Dying from Covid complications, usually respiratory failure exacerbated by secondary infections and multi-organ failure

People develop Covid within two weeks. By then, it should be clear whether ongoing delay or holding of existing IBD meds is needed.

My fellow gastroenterologists overseas do not see a spike in disease presentation or worse outcomes in patients on immune therapies for IBD — and for that matter, nor do rheumatologists in their patients.

Therefore, while this is weak evidence, it is likely that many IBD patients have been infected while on their therapies, and recovered without knowing it or with minimal symptoms.

So, in all this misery, it is nice to be able to provide a little bit of comfort for those who already have to deal with the real challenges of IBD.

• Find the latest detailed Covid information at the Centres for Disease Control and Prevention bit.ly/36kuKDA; the World Health Organisation bit.ly/3cVZoWm; the Mount Sinai Health System bit.ly/2Xp3i3s

• Suraia Boaventura Barclay, MD, is a gastroenterologist and endoscopist. Contact her at 295-6994