Covid-19 through the Lens of frontline doctor: ‘Let’s manage our expectations’

58

Since the beginning of this fight against the CoVid-19 pandemic, my observation is that the government of Ghana has demonstrated great leadership and has constantly made decisions based on available data and science. At any point in time, I observe that the government of Ghana always put the best interest of the Ghanaian first even if it made us uncomfortable for a short while.

The constant updates to citizens by the president himself, giving us as much information direction and reliefs, as deemed necessary for the consumption of the ordinary citizen, is very reassuring and is exemplary. So far I observe that the government of Ghana has been as open and transparent as reasonably possible to Ghanaians.

It has also tried to prevent fear and panic in the country with respect to this pandemic using a series of education, laws and regulating and synchronizing information dissemination with the media houses. Largely, there is this sense of security one feels knowing that the government of Ghana is doing all its possible best to protect its citizens and keep them safe.

There have been challenges along the way. Some citizens have been reasonably responsible; others are just too vulnerable (the very poor and homeless) to keep up with all the medical education and advice. The food distribution could have been done in a much safer way. Though the Government of Ghana tried to feed the vulnerable for free, people still needed to go back to work to make ends meet. In my opinion, the of the night market was a warning sign as to what was to come amidst its social and national security implications.

How long are we keeping the schools, the churches and the mosques closed? Were we going to stay locked down forever? Did we have an end of this pandemic in sight? No! In my humble opinion, the government of Ghana had to assess and determine for itself the path it will take in the fight of this pandemic, bearing in mind the economics, population health, national security and several other factors.

This decision was not going to be foolproof but certainly will have to be made in the good interest of the Ghanaian people. One of such decisions was made when the president in his 7th update, lifted off of the imposition of restriction on movement in the Greater Accra, Greater Kumasi and their environs. This has been met with varying opinions

As a medical doctor who works at the emergency department, I was immediately unhappy because of my own interest but when I considered the interest of the other sectors, I began to understand what a hard task it was to be the president of Ghana in times like this. Let me tell you what is happening in my lenses.

Firstly, according to the Ghana statistical service, Ghana’s population by the end of this year will be over 30million.

The SARS-CoV-2 is a new strain of corona virus. Because the virus is new, no person in Ghana is immune to the infection and as a result the about 30 million persons in Ghana are all susceptible hosts to the SARS- CoV-2.

Hence in the spirit of this principle, it means that without vaccinations all of us are at risk of getting infected with this virus. For those who have already had the infection, it is the expectation that they will develop immunity after they have recovered without treatment. However, there are some report from China suggesting about 14% reinfection rate and questions the idea if immunity after a single infection.

Secondly, it is important to know that at any point in time the total number of people who have the infection are more than those who have tested positive. That means that the number of positive patients is only a fraction of the total number of infected persons.

The World Health Organization has estimated the R0 of the coronavirus to be 1.4-2.5. A group of researchers at Lancaster University suggested higher value of 3.8 last week , but revised it this week to 2.5 as new data became available. A group of Chinese doctors, meanwhile, calculated the R0 to be between 3.3 and 5.47 in research published in the International Journal of Infectious Diseases on January 29. It is therefore safe to assume the R nought (0) of this SARS-CoV-2 which is the cause of CoVid-19 to be at least between 1-3. (https://www.biorxiv.org/content/10.1101/2020.01.23.916395v1 )

The epidemiological definition of ℛ0 is the average number of secondary cases produced by one infected individual introduced into a population of susceptible individuals, where an infected individual has acquired the disease, and susceptible individuals are healthy but can acquire the disease (https://youtu.be/jKUGZvW99os). This value helps in the assessment of how fast in infection spreads. ℛ0 > 1 suggests that an infection will spread exponentially. ℛ0 = 1 suggests containment and a ℛ0<1 suggests that infection is not spreading anymore and hence suggests further that the infection may end soon. All the curve flattening measures outlines WHO and Ghana is aimed at achieving a ℛ0<1.

Figure 1 showing the spread of infection using R0

Another epidemiological information that describes how fast an infection spreads is the Serial Interval (SI). The serial interval of an infectious disease represents the duration between symptom onset of a primary case and symptom onset of its secondary cases. It helps to determine how fast an infection spreads over time.

The shorter the Serial interval, the faster an infected patient is able to spread the infection to susceptible hosts and vice versa. The average serial interval for CoVid-19 is estimated to be between 4.1 and 5.5 days whiles that of influenza is about 2-2.5 days. This means that for every single unfound CoVid-19 infected patient, they will be able to infect another susceptible host in about 4-5 days and the cycle runs on.

Figure 2: a diagram showing the relationship between serial interval and incubation period. The average serial interval for CoVid-19 is about 4 and the average incubation period is about 5. This explains why there are pre-symptomatic transmissions.

Hence, as far as there is no intervention to prevent a susceptible host from getting the infection from an unidentified infected host, one infected person on the loose is likely to infect an average of at least 3 new persons who in about 4 days (which is the average series interval for this virus) will infect an average of at least 3 persons each and the cycle continues. In effect, CoVid-19 as a matter of fact, based on the variables explained, is undeniably a highly contagious disease.

Saying this loud and clear is what the Ghanaian citizenry need to know. It is the truth, which by no means aims to create fear and panic but gives the citizens enough understanding of what the effects of not complying strictly with the preventive advice. It is clear now that no matter the inventions aimed at helping citizens to stay safe, if citizens do not fully comply to the directives or if citizens are not compelled to comply, the virus will keep spreading.

For now we do not have 100% compliance and so the realistic expectation that citizens need to have is that the number of positive cases will continue to increase exponentially till we reach peak and not because of enhanced surveillance or because we are doing lots of testing (which is good) but because this virus is highly contagious. Remember that, the number of positive cases is only a fraction of the number of infected cases yet to be identified. Also testing negative today does not mean one will be negative forever because we are dealing with highly contagious CoVid-19.

Because the effectiveness of all our mitigation measures is dependent on human behaviour, I am happy that the government is embarking on wide spread public education to inform citizens of their crucial role in the fight of this pandemic in addition to all the mitigation strategies outlined.

Also depending on how citizens behave the estimation Ghana made using the WHO model, as used by the president’s adviser, may be better or worse. This is true.

In no way aimed at creating fear and panic but to make citizens know that despite the interventions by the government, we have a huge and collective active responsibility as citizens to push us closer to the end of this pandemic so that we can go back to our normal ways of living as soon as possible. One person’s error will affect all of us in a huge way and so let us be our brother’s keeper and play our collective roles in this fight.

It is therefore reasonable to manage the expectations of citizens by making them know that it is a reasonably normal expectation that the number of positive cases will continue increase over time until such a time when have we have all infected cases isolated and that the rate of spread is dependent on how compliant citizens will be with the mitigation strategies outlined by government.

A highly contagious disease does not necessarily translate as a highly deadly disease. For example, the common cold is a highly contagious illness but rarely fatal. The measure of how deadly a disease may be is determined by its case fatality rate (CFR). The higher the case fatality rate the more deadly the disease may be.

The cases fatality in Ghana as 25th April, 2020 is 0.782% representing about 8 in 1000 positive cases. This value is likely to be lower as the number of positive cases increases. What that tells us is that, though CoVid-19 is highly contagious in Ghana, as at now, it is not as deadly since the case fatality rate is low.

Of the 1279 positive cases, majority of them, representing 98.905% have mild to no symptoms and are responding well to treatment. Only 1.095% of them have exhibited severe symptoms or have died. 4 patients representing only 0.313% of the active cases are in the intensive care unit (ICU) out of which 1 has been intubated. 10.477% of the positive cases have recovered so far but the rate of recovery seems unpredictable. This is because the duration of time between the start of treatment to recovery is variable. This picture painted by the available data does not suggest a very deadly illness for now.

Table 1 showing current CoVid-19 data in Ghana as at April 25, 2020

In my humble opinion, it is important that in analyzing our data, we do not put too much emphasis on the positivity rate and negativity rate and hence not use it to erroneously speculate the future when we are dealing with a highly infectious disease with a ℛ0 of at least 3days like CoVid-19 and with an average serial interval of about 4.1 days With the ℛ0 and serial interval of CoVid-19 in mind, having a low positivity rate does not therefore technically mean that few people are getting infected. This in my opinion undermines how contagious this infection is and will negatively affect the behavior of citizens in the fight of this epidemic.

Should we keep chasing and stopping the virus allowing the virus to run its course knowing that the case fatality is low? Or should we do a hybrid of both? This is the difficult question the government has to one-day answer. Also case fatality rate may be low but the absolute numbers may still be high.

In an ideal situation, the best option will be stick to all the measures that keeps us away from the virus and then actively chase and find all the infected people and isolate them from the community to stop the spread of the virus. However in Ghana and everywhere else in the world, we are struggling with identifying all of the infected persons. Also, Testing rapidly and getting results early enough to chase the virus is also a problem because of the load on the testing sites as at now (I am aware of the plans on going to change this).

The way I see it, the intension to chase the virus is an excellent one but practically a very difficult one at least as at now. From figure 2, it is clear that whenever the average serial interval is shorter than the average incubation period, there is a chance of pre-symptomatic transmission as is the case with CoVid-19.

This implies that contact-tracing methods must compete against the rapid replacement of case generations, and the number of contacts may soon exceed what available healthcare and public health workers are able to handle. Pre-symptomatic transmission is likely to have taken place and may even occur more frequently than symptomatic transmission.

A substantial proportion of secondary transmission occurring before illness onset indicates that many transmissions cannot be prevented solely through isolation of symptomatic cases, as by the time contacts are traced they may have already become infectious themselves and generated secondary cases (Fraser et al., 2004). With this fact, it seems prudent that the Government of Ghana initiated the enhanced contact tracing and community screening in identified hot spots for CoVid-19 and it is my hope that it continues doing same all over the country.

Ghana finds its self in the tropical region where we have abundant sunlight. Increasingly, research is showing that, the sunlight might help decrease the life span of the SARS-CoV-2 virus. Also, Ghana has a relative young population compared to Italy. This therefore suggests that the percentage of the elderly population with comorbidities who are at risk of having sever forms of the illness may be low. The dynamics of this pandemic maybe uniquely different from what is happening abroad.

There are two case scenarios that will lead to the end of this pandemic in Ghana.

Scenario 1

Many people will get infected. Survivor of the infection may develop long term immunity towards the SARS-Cov-2 virus. The picture from the Ghana data looks good as over 98% of the infected patients are exhibiting mild symptoms and are likely going to survive. If more than 80% of the population become immune to the SARS-CoV-2 after infection, the rate of transmission of the virus will slow down progressively until the virus dies out (R0<1). This is herd immunity. Herd immunity can be achieved faster with vaccination, however since this virus is new, we seem far away from getting appropriate vaccines developed on time. Scientists all over the world are however working hard to make this happen and on time. The burden on the health care systems however, will be huge as there will be a lot of patients to take care of.

Scenario 2

The government of Ghana has implemented and is enforcing curve-flattening measures such as;

  1. Actively identifying and isolating infected patients to halt transmissions
  2. Practicing appropriate social distancing
  3. Actively practicing hand hygiene
  4. Avoiding handshakes
  5. Not touching face
  6. Observing cough and sneeze etiquette
  7. Wearing appropriate face masks
  8. Self-reporting via 112 and self-isolation
  9. Public education targeted at educating on prevention of the disease and the effects of stigmatization
  10. Frequent cleaning of surfaces
  11. Ban on public gathering
  12. Closure of our borders to prevent imported cases
  13. Expanding testing sites
  14. Distribution personal protection equipment’s (PPE’s)

These measures will distance susceptible citizens from getting contact with the virus and hence prevent infection. Over time, the virus transmission will reduce progressively till there it dies out when there is no host to infect (R0<1).  This is highly dependent the behavior of citizens. If these curve-flattening measures are adhered to, it well lead to the reduction of the number of infected persons in the long term and hence reduces the burden of the health care systems of the country.

Figure 3 The 2 pathways to the end of pandemics

Each path will have its pros and cons. So following health advice and not getting infected is the best personal choice anyone can make. If u get infected in the process, it is good hope to know than over 98% of the chance per the available statistics is that u may survive. Protect the vulnerable population; the old and those with co morbidities by following health advice and by being honest.

I urge the government to keenly monitor the quick implementation of all its mitigation strategies Government should manage the expectation if its citizens by identifying and using Ghana specific R nought and serial interval of the CoVid-19 to make realistic estimations of the number of people who are likely to become infected over a particular time frame. This will aid citizens to make informed decisions and Health facilities to make realistic adjustment in a Ghana specific way.

Let us embrace the new way of living because life as we know it will never be the same after this pandemic.

The author, Dr Papa Kojo Mbroh is a Resident Doctor at the Emergency Medicine Department of the Komfo Anokye Teaching Hospital (KATH)

 

Source:Myjoyonline.com