Covid-19: Nutritional issues and public health management

Now on the world stage, Covid-19 has passed the containment stage, and political and health care systems everywhere have moved directly to disease management. This was largely inevitable, given the viral attributes of high transmission rates and long incubation; and the common political tendency to normalcy bias.

Some nations have relied on contact tracing and lock-down to slow the increase in infection, essential in preventing hospital overload and – hopefully – in starving the virus of fresh victims. China appears to have done so fairly successfully, effectively militarizing their viral control effort in tandem with sophisticated online tracing and localisation tools available via WeChat. South Korea has been able to achieve something similar, combining sophisticated tracing tools with a highly educated, motivated and relatively homogenous population who were willing to take appropriate actions such as self-isolation and, where necessary, self-reporting.

It remains to be seen if other, less disciplined nations in Europe and North America will be able to follow suit. The natural and logical desire of many European states to close their borders was initially blocked by ideologues in Brussels.  Acting independently, however, France has joined Italy in imposing a national lockdown; and Germany, Austria and Denmark have joined the Czech Republic, Hungary and Poland in closing their borders. The Czech Republic has also joined in the mass quarantine movement, sealing off some towns entirely. 

Unfortunately, given the rapidly increasing numbers of cases within each of these countries, it seems doubtful that borders closed so late in the day will affect their internal problems to any great extent. The initial reluctance of Brussels to allow the building of bulkheads has already set these nation states on trajectories of increasing death, disability and social fracturing. 

In any case the problem with lock-down, if it can be achieved, is that it is rarely completely effective, and infection may reappear once social conditions are normalized.

Other nations have chosen a different path with the UK in particular having decided, initially, to opt for herd immunity. The aim here is to trade larger numbers of initial cases with a longer-term reduction, achievable once 60% of more of the herd have been exposed and gained a degree of resistance to the virus. The problem with this approach, however, is that no one yet knows how many recovered individuals generate strong and/or permanent immunity. Initial reports indicate that after Covid-19 infection, immunity may not always be strong or long-lasting; and if these reports are representative, effective herd immunity may not be easily achievable. Viral mutation, as occurred with the 1918-19 influenza and may have already occurred with Covid-19, can also undermine the herd immunity strategy.

Both of the above options incur significant economic costs, due to disruption of supply chains and working patterns; and some believe that these may be so severe as to impact health statistics even more profoundly than the disease itself. There is a growing need, therefore, to shift resources to acute and to systemic disease treatments. 

There will always be a place for symptomatic approaches (decongestants, iv drips, nasal washes and in severe cases ventilators and antibiotics / antifungals), but it is self-evident that more fundamental strategies are needed to protect our national health. Which brings us to anti-viral drugs and vaccines.

Initially promising reports of using combined antiretrovirals and neuraminidase-inhibitors have faded, and it remains to be seen whether more recent reports of combinations of antiretrovirals and anti-malarials and/or remdesivir, will be substantiated. Data collection is at an early stage, and both efficacy and safety remain to be proven. A number of vaccines are in prototype production and pre-clinical testing, with at least one vaccine already used in individual named patients, but here again there is insufficient data at the time of writing to issue clinical guidelines or recommendations. Can more be done?

Going back to the basic epidemiology, it is known that 80-85% of infected individuals suffer only minor symptoms and do not require hospitalisation. While size of inoculum may play a role, the functionality of the innate immune system and the presence or absence of comorbidities appear to be the critical determining factors. In both of these factors nutritional status plays an absolutely crucial role, and this opens the possibility of using nutritional tools to increase the size of the group who experience only mild illness, and reduce the numbers requiring hospitalisation to more manageable levels.

The disease progresses through a series of stages. It begins with a virusaemia lasting 7 to 9 days, which is associated with relatively nonspecific symptoms such as nasal discharge, sore throat and mild fever. In 80-85% of cases the disease does not progress beyond this point, because the innate immune system succeeds in overcoming the viral challenge. In approximately 15% of cases the innate immune system fails to contain the virus and the disease progresses to a mixed viral and bacterial pneumonia, and finally to a mixed viral, bacterial and fungal pneumonia as the immune system breaks down and inflammation overwhelms the patient.

The above timelines indicate that it is the integrity of the innate immune system that determines, at least in part, whether the Infected subject progresses from viraemia to a more serious illness. If innate immune function could be improved, and given the evidence of widespread sub-optimal innate immune function this should be achievable, the impact on healthcare requirements would be considerable. Moving from an 85/15 split towards a 90/10 split would cut the need for intensive hospital care in half. Various elements of the innate immune system can be enhanced using such tools as the 1-3, 1-6 beta glucans to increase immune cellular competence, and iron and thiocyanates (co-factor and substrate respectively), to optimise the humoral component lactoperoxidase (LPO). Exogenous LPO may be an effective treatment on its own. There is circumstantial but persuasive evidence that the LPO system has the ability, if it is working well, to damage influenza and probably coronaviruses to the point where they cannot infect new cells in the body (1-6). The effectiveness of such composite nutritional interventions are not yet proven but they are supported by circumstantial evidence, and unlike the pharmaceutical approaches, they have very wide therapeutic indices. This makes them eminently suitable for general useage, and for consideration 

In public health strategies going forwards.

REFERENCES:

1. Patel U, Gingerich A, Widman L, Sarr D, Tripp RA, Rada B. Susceptibility of influenza viruses to hypothiocyanite and hypoiodite produced by lactoperoxidase in a cell-free system. PLoS One. 2018 Jul 25;13(7):e0199167.
2. Gingerich A, Pang L, Hanson J, Dlugolenski D, Streich R, Lafontaine ER, Nagy T, Tripp RA, Rada B. Hypothiocyanite produced by human and rat respiratory epithelial cells inactivates extracellular H1N2 influenza A virus. Inflamm Res. 2016; 65(1):71–80.
3. Cegolon L, Salata C, Piccoli E, Juarez V, Palu G, Mastrangelo G, Calistri A. In vitro antiviral activity of hypothiocyanite against A/H1N1/2009 pandemic influenza virus. Int J Hyg Environ Health. 2014; 217(1):17–22.
4. Sugita C, Shin K, Wakabayashi H, Tsuhako R, Yoshida H, Watanabe W, Kurokawa M. Antiviral activity of hypothiocyanite produced by lactoperoxidase against influenza A and B viruses and mode of its antiviral action. Acta Virol. 2018;62(4):401-408.
5. Panon G, Tache S, Labie C. Antiviral Substances in Raw Bovine Milk Active Against Bovine Rotavirus and Coronavirus. J Food Protection. 1987: 50:862-886
6. Fischer, JA. Augmenting antiviral host defense in the respiratory epithelium. PhD thesis, University of Iowa, 2009. https://doi.org/10.17077/etd.9hpirtqh