The Mystery of COVID Toes
Posted: Oct 21, 2020
COVID toes is a phenomenon that started to be reported in Spain and Italy at the start of winter during the first wave of the novel coronavirus pandemic in 2020. The reports were finding a very high incidence of chilblains of the toes in those with COVID-19. The news media latched on to these reports and a lot of attention was paid to them. A lot of interest has been generated from the general public and health professionals in the whole phenomenon of COVID toes.
There are a number of pathophysiological processes associated with COVID-19, such as issues with the blood, the cytokine storm and inflammatory processes that could affect the circulation in the toes that predispose the foot or toes to developing chilblains. Chilblains are a poor response of the microcirculation to changes in temperature. If the small blood vessels do not respond properly, waste products accumulate in the skin leading to an inflammatory process that is the chilblain. It easy to see how COVID-19 could increase the chance of developing a chilblain. Several early histological studies from biopsies of the chilblains in those with COVID-19 did report that were elements of the infection present in the tissues. However, other studies have reported that there weren’t any, so it has started to get quite confusing as to what the link between the two entities actually are.
The problem is that with the passage of time and further investigation there is an increasing number of reports that there is no link between COVID-19 and chilblains and the high incidence is just a coincidence. There is one report from the Nordic region that there has been no increase in the incidence of chilblains there. Other recent investigations by the use of biopsies and post-mortem autopsy have found no coronavirus elements associated with the chilblains. There is speculation that the alleged increase in the incidence in some countries was a problem with the lifestyle changes due to the lockdown during the pandemic and that they are not really part of the pathophysiological process of the infection. These lifestyle changes during the lockdown include things like being more sedentary, perhaps the less wearing of shoes, being more exposed to air-conditioning and the constant warmth indoors. These lifestyle changes during lockdown may have been greater in countries like Spain and Italy and the changes could not have been so great in the Nordic countries. In Nordic countries they might just be better at managing the issues around temperature fluctuations that are considered a risk factor in chilblains. This could easily account for the different incidences in those two regions.
An episode of the podiatry livestream, PodChatLive was on this very topic. The hosts chatted with a podiatrist from South Africa, Nadia Dembskey who is about to embark on a PhD on the topic. All of the above issues were litigated, and they still have not been resolved. Given all the conflicting literature and the conflicting ideas that there are on this, it may be a while before the science gets to resolve this.
Craig Payne is a University lecturer, runner, cynic, researcher, skeptic, forum admin, woo basher, clinician, rabble-rouser, blogger and a dad.