Discussion:
Based upon our findings, COVID-19 does not significantly affect individuals with CF. This can be due to infection control measures and minimizing contact that hold true in many regions of the world but does not apply to these two cases. One explanation for this observation can be the CF medical therapy regimen that includes hypertonic saline. Previous studies have shown that salt can affect viruses. In a study by Zhang et. al. (4), high salt was identified as a crucial regulator of signaling. In another study by Siber and Podgornik (5) the influence of salt was shown on encapsidation of single- stranded viral RNA molecules. This influence was also shown on double stranded RNA at 250 mM sodium chloride. 5% hypertonic saline is equivalent to 0.85 mM NaCl. More studies are needed to answer the therapeutic role of hypertonic saline in treatment of COVID-19.
There can be additional protective factors in CF such as genetics or immunological factors that remain to be identified. It appears that patients with CF need an additional risk factor such as malnutrition or severe airway obstruction that puts them at risk from COVID-19 infection. There is still significant unknowns in dealing with the COVID-19 infection and there is no place for complacency. Until there is more scientific data, social distancing and infection control measures should be continued.