Flattening the curve: Cost effective option in combatting Covid-19 – Ebuta Agbor
Governments worldwide are not infallible; they sometimes make mistakes in action and inactions, take missteps or adopt poor decision. While, the undesirable decisions are typically well intentioned at onset or superficially utilitarian, they are occasionally products of an obstinate attachment to traditional guidelines generated by quixotically bureaucratic institutions. More often than not, these institution approval processes are unapologetically steeped in a grindingly slow process, posited as inbuilt checks aimed at preventing process abuse.
The major responsibility of governments includes, but not limited to making sound, credible and workable decisions that serve the common good ofits citizens, which ironically becomes a weakness, as “they” become exceptionally careful about not appearing to deviate from the best practices, as recommended by certifying or guideline setting institution. This happens quite often, even when cost effective but contrary uncertified options exist.
While one does not seek to underplay the important role that these organizations, local guidelines setting institution and their general administrative bureaucracies sometimes impede swift, cost effective and intentional actions play. We must remember that these institutions are occasionally also subjected to or subscribed to decision processes that are influenced by many factors and determinants, not entirely free from political or undeclared interest control. This is despite debatable undertones or outright proclamations of altruism.
The universal use of face mask is one huge topic that underpins the principles I would attempt to expound, with the aim of proposing an addendum to the arsenal we as a people have so far unleashed on COVID 19, with variable expectations. In the last 3 months since COVID 19 arrived the shores of many countries, sweeping through (initially slowly and then exponentially) in most, there has been an explosion of research posits and interests in the areas of prevention, control and management of the epidemic.
Epidemiological prediction will divide the natural history of epidemics into “THE LAG, THE LOG, PLATEAU/PEAK AND DECLINE PHASE”. While the spike in cases plotted on the Y axis is modifiable, the duration of the curve represents a good chance at modifying its impact on the health system. Thus, while curves with short transition time can crash health systems, those with longer transition times allows for a far more tolerable pressure on the health system.
Figure 1 below shows a flattening curve of the number of cases and the proportional implication on the capacity of the health care system
Figure 1: a flattening curve [source; CDC]
The above figure shows the implication of an epidemic, on the health care system capacity from the time the epidemic arrives the door steps of an immunologically naïve populations, it takes root and spreads through direct and direct contacts slowly initially, this is can be referred to as the Lag Phase. Here case rate are the lowest. Subsequently, the next phase;Log Phaseensues, here case rate achieve exponential growth and quickly ascends to the maximum level before it flattens into the next phase the Plateau Phase/Peak.
During the LAG PHASE, the number of patients presenting increases slowly, panic fear usually results from lack of information and there is little real pressure on the health system. While, in the LOG PHASE, this is not the case, as cases increase, quickly causing justifiable panic and quickly saturating most heath service points. During this phase there is an increase in the mobilization of men, money, materials and management.
It’s notable that if countries considered to be developed are grappling, one can only be frantic and bothered as to how developing countries like Nigeria will cope.
During the next phase PLATEAU/PEAK PHASE, as the epidemic achieves a wider spread, affecting the majority of the population, the rate at which new cases present becomes steady or peaks momentarily before its decline commences.As the majority of the population who became infected, develop antibodies and cellular immunity, the case rate of new infections begins to decline, with the epidemic dying a natural death.
If the epidemiological behavior of other CORONA VIRUS STRAINS is anything to go by, about 2% of the population achieves a healthy carrier state and will inadvertently serve as a source of re-infection to a small subset in the population who are ab-initio un-immune or immuno-suppressed. It can also be projected that, at the end of the natural epidemiological history of this pandemic, the SARS COV 2 will join other CORONAL VIRUSES which together as a group account for 5-10% of respiratory tract infections by viruses every year.The duration it takes for the epidemiological curve to transit determines the case rates, meaning that steeper curves puts more pressure on health systems than fattened curves, easily surmised from the curve in figure 1.
Thus public health expert’s advocates that countries must try to flatten this epidemiological curve, slow down infection rate, thus allowing patient presentation to even out at a rate that even weak health systems can also afford to manage. We can thus estimate for example that, if a steep epidemiological curve takes 4 months to transit through the 4 phases, any manipulation that allows this same curve to transit over a 12 month period will flatten the curve appreciably, spreading out symptomatic health presentations and permitting less pressure on the health systems, which will then translate to more efficient case management and therefore more lives saved.
Given the expected natural history of COVID 19, public health specialist in GERMANY had projected that about 70-80% of the population might be infected at the end of a natural, unhindered, epidemic cycle. This is no surprise, given that the critical cut off for community level herd immunity is 80%. This means that, if we were to extrapolate this concept to, a country like Nigeria with a population of 200 million people, we can surmise that at the end of this epidemic cycle, given the worst case scenario, 160million people could be infected at a final count, happily 95% of which should have non critical disease (based on the Wuhan, Chinese case scenario). Inferentially, this suggests that with flatter curves, even weak health systems may be able to deal with these numbers, while the best of health systems will collapse if all these present under a short period of time as will be the case with steep curves.
Much has been said about the measures being promoted to achieve the Holy Grail of flattening the curve of this pandemic. Sadly as is the practice, most of the funding is presently being channeled toward the purchase of heavy duty equipment’s (massive purchase of ventilators, hospital beds etc.) that might not even be deployed, given the dearth of specialized and skill personnel to intubate and manage them (a discussion for another day). This equipment’s is at risk of laying waste especially in the future long after COVID19 has transitioned to an ignorable endemic infection. The emerging data which suggest that as much as 50-70% of mechanically ventilated patient succumb to the final fate that awaits all men is equally disturbing. While this is not a call to discontinue the purchase of ventilators, it is of utmost importance and as a recommendation that we re-task and refocus our resource wisely for sustainable effect on the fight against the virus outbreak.
The USA has estimated that it will need 1million ventilators for 350million people meaning that ratio of ventilator to population was estimated as 3 to 1000 in the worstcase scenario. If that is anything to go by, the Nigerian population of 200 million people will require 600 thousands ventilators in the worst scenarios. Recent innovations suggest that if the technology that allows 10 patients to use 1 ventilator is deployed, we can drop this need of ventilators to 60000, and to add, if we can flatten this epidemic curve further and slow this infection rate by 10times the worst case scenario, we will only need 6000 ventilators, an achievable target (I will stretch this no further).
INFECTION SOURCE CONTROL
The concept of infection control embraces many facts and determinants; the COVID 19 pandemic has shown us how intimately we interact, albeit, unknowingly. One of the key principles expounded in controlling this infection is the concept of source control, which will be at the center of my propositions. Source control measures includes but are not limited to cough and sneezing etiquette, (+ permit me to add speaking etiquette), hand hygiene and social distancing of upto 2meters amongst others.We can almost say that if people stop sneezing, coughing and talking, we would have arrested COVID 19 in its track and reverse this pandemic. However this will be impractical OR is it, even if this was remotely possible, literally speaking,it would have meant, there will then be no need for hand hygiene and social distancing to prevent Covid19. The problem with sneezing, coughing and talking is that these activities release respiratory droplets, which are the main agents of transmission. So were we to curtail the release of the respiratory droplets successfully, we would have dealt the transmission of COVID 19 a major blow, and prevented the viruses attempt to leave our civilization in tatters.
While the current guidelines by the regulating institutions, promotes cough etiquettes, nothing is said about speaking etiquette. Indeed cough etiquettes can be classified as an active source control measure, but the use of face mask though considered a passive source control measure, is by far a more effective public health intervention. This if synergized with other measures like social distancing and hand hygiene will knock off the speed of COVID 19 pandemic, flatten the epidemic curve and almost restore life back to normal.
There is an overwhelming evidence based practice, which makes the case for the use of infection source control measures as a potent public health tool against respiratory infections like Covid 19.
There are different types of face masks; the N95 and FFP, which if size-fitted are promoted as being able to prevent the wearer from inhaling 95% of infective respiratory droplets upon exposure (meaning that there is still a 5% risk). These work better if properly fitted to size and best if vaseline sealed. They are promoted for use by health care workers exposed to infective patients. They are more expensive and demand issues affect availability too.
The surgical face mask on the other hand (commonly colored green or blue), were originally produced to prevent surgeons from infecting patients with their nasal or oral secretions during surgery. They however quickly found use in tuberculosis clinic as infection source control measures. Used by open TB patients in order to prevent them from infecting the health worker or other un-infected persons. They are rightly presented as having “no use for protecting uninfected people from infected droplets” thus the World Health Organization (WHO) recommended against its use by this select population.
Lastly, the homemade face mask which can be easily sewn up by the tailor’s apprentice, seamstress or designer are 3 times less efficient than the surgical mask in its simplest design, but nonetheless useful. This is because, there is evidence to suggest that, this homemade face masks can trap as much as 80% of expelled droplets from a coughing, sneezing or speaking by infected COVID 19 patient. I propose to improve the design of this simple homemade face mask, by introducing an inner layer of cotton which will absorbs oro-nasal secretions better and increase the current surface area by 100 % to improve on coverage, fit and performance.
It is of utmost importance to remember that current evidence suggest that as much as ≥ 50% of COVID 19 patients may be asymptomatic i.e has no symptoms at all but still possess the ability to transmit SARS COV2 while coughing sneezing, or speaking to uninfected people, through release of infected droplets.
But the JAMB questions like Nigerians like to say is “HOW DO YOU DIFFERENTIATE THE ASYMPTOMATIC INFECTED FROM THE UNINFECTED?”
For the purposes of the next set of proposition I will be making, I will like classify the countrywide population into four groups:
- Infected symptomatic (these have COVID 19 but are present with symptoms, like coughing or sneezing and can actively transmit SARS COV 2).
- Infected asymptomatic (these have COVID 19 infection but do not have any symptoms).
- Uninfected but having suspicious symptoms (these do not have COVID 19 but has cough or catarrh as symptoms of respiratory infection from other causes not COVID 19).
- Uninfected with no suspicious symptoms (these consist of the population without symptoms like coughing or sneezing and are susceptible)
The challenge, which is a public health nightmare,is; while we cannot differentiate betweenthe infected symptomatic from the uninfected with suspicious symptoms prior to testing and can only differentiate between the infected asymptomatic, from uninfected with no suspicious symptoms only after testing, especially counter-posed against the fact that testing is restricted to mainly symptomatic patients.
It is therefore proposed that:
- Country wide measures should be taken to promote the production of homemade face mask with modifications as specified above (cotton inner layer doubling the surface layer of the mask to improve its ability to trap respiratory droplets)
- That, the public are encouraged to make and share this mask for use mandatorily by all Nigerians(except health workers at risk who will require N95 grade face mask as appropriate).
NB: This homemade mask will be reusable and will save massive foreign exchange spent on importing face mask and serve to diffuse anxiety and pressure. In any case people are already using face mask despite WHO counter advice, thus an endorsement with explanations will serve a good purpose.
- While the proposal in (2)above (countrywide use of modified homemade face mask)may be criticized, we must remember that adoption of new health behavior takes a while no matter how elementary. In addition, learning new habits weeks before the arrival of SARS COV will be a major public health coup to our advantage. Instituting the above measures in the general population will arrest the release of infective respiratory droplets from both group 1 and most importantly group 2 and also limit transmission when people are simply conversing (a grossly underestimated contributor to transmission burden).
We estimate that, because this modified homemade face mask can trap 80% of infective respiratory droplets and achieve some level of infection source control, new infection rate will drop significantly if the countrywide,modified face mask use policy is implemented immediately. We can also extrapolate that, given a potential reduction in new infection, if this measure is implemented, the case rate will drop, resulting in a decline in the epidemiological peak and thereby flattening the curve appreciably. This will translate to fewer patients at any point in time and will effectively mean that even weak health systems in the developing world will be able to handle lower trickles of patients(See Fig 1.).
The Czechs imposed the mandatory use of home-made face masks for the whole population, propelling their population to sew and donate massive amount of homemade face mask, andsucceeded in flattening their epidemiological curve.This ensured that they retained the capacity to manage the trickles of patients in need of health care services despite a COVID 19 epidemic. The Spanish, Italian and most recently the USA experience when counterpoised speaks volume.
The Federal Government, as a matter of urgency, should enact a law that mandatorily affirms the use of facemasks, encourage all to contribute to a face mask bank or channel a fraction of donations by well-meaning Nigerians for the massive production and distribution of these reusable modified homemade facemasks. Develop and share guidelines or educative materials on how to care for these facemasks (like washing them every night, drying overnight for reuse the next day, and hand hygiene before removing or putting them on).These propositions side by side with other measures in place will no doubt work synergistically.
In conclusion, despite being personally fanatical aboutthe strict adherence to WHO guidelines, the recent position against the use of masks for all is rather unsettling. I am constrained to break ranks on this occasion, having reviewed several materials and rigorously evaluated our position as a country. I am confident that, if were we to promote this simple measure, we would have done a lot to arrest this epidemic and might even be able to remove movement restrictions and get our economy back on track in this perilous times. In the near future, COVID 19 pandemic will pass over, when we will be conducting an audit of where we stand and how far we have come, it will be painful to say had we known. Therefore, the immediate implementation of these population mobilizing, cost efficient measures. Finallywe might gaining something by adding this modification to our current strategy, but most certainly we will lose nothingat the final verdict post audit.
God bless us all, in support of MASK4ALL.
Dr Ebuta, Agbor Neji
Volunteer Vice President of the Medical Initiative for Africa.