On 31st December 2019, the World Health Organization (WHO) Country Office in China, was informed of cases of pneumonia of unknown cause detected in Wuhan City, Hubei Province. On January 7, 2020, the causative pathogen was identified as a novel coronavirus (2019-nCoV), following which the International Committee on Taxonomy of Viruses (ICTV) named it the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The disease was subsequently named Covid-19.
Ghana recorded its first two positive cases on the 12th of March, 2020 which increased to 6 cases by the 14th of March, 2020. The President of the Republic, His Excellency Nana Addo Dankwa Akufo Addo, subsequently announced some mitigation measures including the ban on all public gatherings, including the closure of public and private schools, and suspension of religious activities. Theserestriction measures were further scaled up to include the closure of all land, sea and air borders to human traffic on 22ndMarch, 2020. This decision to close down our ports, was taken after the 19th Covid-19 case was reported with the first death recorded in Ghana. The closure of the borders with the enforcement of mandatory quarantine resulted in the identification of 115 Covid-19 cases who would have ordinarily entered the country and potentially initiated massive community spread. With these rolling numbers in view, a further decision was made by the President tostrategically restrict movement of persons in the Greater Accra and Greater Kumasi Metropolitan Area and contiguous districts, for a period of two (2) weeks. The decision took effect on Monday, 30th March, 2020. Although the strategy for identification of contacts and testing was not too clear at the time, further information from the Presidential Advisor on Health, Dr Anthony Nsiah-Asare indicated that mandatory testing was to be conducted for some persons in the restricted areas in order to ascertain the true number of persons infected. To-date, updates on the website of the Ghana Health Service indicate that 44,421 have been tested out of which 636 are positive. In the meantime, testing in Ghana has been carried out by three designated centres with facilities to conduct molecular testing (Polymerase Chain Reaction on an RT platform); the Kumasi Centre for Collaborative Research, the Noguchi Memorial Institute for Medical Research and the Korle Bu Public Health Reference Laboratory. Testing using quick, easy and fast point of care diagnostics has not yet been initiated in Ghana.
Why Partial Lock Down?
The objective of the partial lock down as communicated by the President was to scale-up effective contact tracing of persons who have been exposed to infected persons, test them for the virus, and, if necessary, quarantine for additional observation and isolate those requiring treatment, should they prove to have the virus. Indeed, the World Health Organization has stated that “lock-down” measures do not extinguish epidemics but only buy time and reduce pressure on health systems. Lock-down becomes effective if is combined with enhanced contact tracing and testing to find every suspected case especially at the community level. This can prove to be quite daunting in socio-cultural environments such as ours. However, additional measures on the heels of the partial lockdown appear to be holding at the moment and all stakeholders involved ought to be commended for their efforts at this, although there appears to be counter-productive actions resulting from distribution of food by government with the consequential inadvertent population gatherings.
So what is the science behind these lock-down interventions?
One of the most important statistical parameters which is used to gauge the effectiveness of an intervention especially in the case of infectious diseases is the reproductive number (R0) or infectivity rate (λ). R0 of an infection is the expected number of cases directly generated by one case in a population where all individuals are deemed to be susceptible to the infection.R0 is mathematically defined as R0 = where is the average number of infections producing contacts per unit time, with a mean infection period of . What this means is that R0 can be reduced by decreasing the value of through reducing the number of contacts per unit time. This is what social distancing aims to achieve by having people stay at home to prevent a propagation of the infection through reduced contacts with the rest of the population.
Data available from countries affected by Covid-19 show thevalue of R0 is around 2.5. This means an individual with coronavirus has the potential of infecting about 2-3 other individuals within a unit time. This R0 may however vary depending on the variables at play in each country. One focus of research should be to determine the actual value of R0 in Ghana. In order to reduce epidemics of Covid-19 infection, itis important to explore effective ways of reducing the value of R0 below 1. Reducing the value of R0 will flatten or crush the epidemic curve and reduce the spread of Covid-19.
How do we flatten the epidemic curve?
Available data from the Imperial College Covid-19 Response Team has demonstrated that not putting in any intervention can result in having about 75% of the population infected. This implies, If Ghana had not put in any mitigation measuresagainst Covid-19 and allowed the system to run normally, at least 75% of Ghanaians (22.5 million) would have become infected. With the current global case fatality rate of around 4% for Covid-19, it would have been expected that 900,000 individuals who may mostly constitute the elderly populations in Ghana would become critically ill and require intensive care management at intensive care units (ICUs). Additionallyabout 300,000 individuals living with HIV/AIDS and over 2 million individuals living with diabetes, hypertension, cardiovascular disease and cancers may be hospitalized for covid-19 infection. Given the low number of ICU beds(approximately 300), and few ventilators (about 200), it is expected that the disease would have assumed exponential epidemic curve putting the lives of about 1 million individuals at risk of death.
In the meantime, approaches to flattening the epidemic curve or better still crushing it can be achieved through the following measures using tactical balancing act on the heels of sound epidemiologic, demographic, sociocultural and geographical mapping and mathematical modeling techniques. These are;– Herd Immunity Approach,– Total Restriction Strategy and – Heavy Selective Restriction and Flexible Approach.1. Herd Immunity Approach: This technique allows the disease to run its natural cause so that the at-risk population become infected achieving a set target of population immunity that protects others from contracting the infection. Those who recover then will become immune to the virus and subsequently protect others. The approach was earlier adopted by the United Kingdom but later back tracked due to the huge number of infections and deaths there were recording.Thedownside of this strategy is that, a significant number of Ghanaian could lose their lives if we were to allow this natural pathway of herd immunity. To date no country in the world has been able to achieve the required herd immunity to combat Covid-19. Are we as a countryprepared to sacrifice these lives? Certainly not!! The other side is that the virus could mutate and be reintroduced into susceptible populations and by thatmay begin another epidemic wave which could go on and on given the versatility of the current virus we are dealing with.
2. Total Restriction Strategy: Restriction strategy involves ordering social distancing, total lock down, banning of large gathering, travel restrictions and closure of air, land and sea to human traffic and implementing aggressive plan for enhanced community surveillance, contact tracing and testing of all locked down areas. Total restriction may cut off the reproductive number of the Covid-19 to below one and reduce the spread and fatalities. But for how long should these restriction measures be put in place? Can Ghana afford over a month nationwide lock-down? Can Ghana address the economic and social implications of total lock downs?Dowe have capacity to effectively implement contact tracing for the whole country and test every suspected individual? The answer is most certainly a very big no!!
Given our unique social structure with over 60% of individuals in the informal sector, it stands to reason that such draconian measures will be ineffective and only lead to malnutrition and starvation for millions of people. This will eventually reduce the immunity of the very population we are trying to protect and make them rathermore susceptible to Covid-19 infection. At this stage, one has to remember that comorbidities increase one’s risk of acquiring the disease. Again, a prolonged total lock-down and restrictions will starve the economy and slide the country into deep recession that mayl be difficult to revive. Total lock-down wouldn’t even solve the problem, because we would be just postponing the epidemic for our country. When later, these social distancing measures are relaxed, people will still get infected in their millions and die. What is typically referred to as a rebound phenomenon. Total Restriction is certainly not the way to go for a country like Ghana which heavily depends on imports and taxes from the working class to build its economy.
Heavy Selective Restriction and Flexible Approach: In this approach, one needs to act more quickly and aggressively to order restriction or lock-down of potential hotpots based on evidence of data collected from the infected population. Such selective lock-down should be combined with education of the population on hygienic practices, intensive testing, surveillance of all suspicious deaths and illness, screening and testing of symptomatic and asymptomatic subjects, use of mobile apps to track interactions with infected persons, isolating the at risk populations (like the elderly), using temperature guns to screen as public places, encouraging home isolation of infected subjects and household quarantine. Other activities like public placedecontamination and disinfection, equipping medical facilities, travel bans in restricted areas would need to be enforced. This approach would equally reduce the R0 to less than 1 and eventually cut off viral growth in the lock-down areas. Once the population goes through this period, a flexible approach is adopted where measuresare relaxed for individuals to go back to their normal duty but with social distancing, disinfection, hygienic practices and reduction in large public gathering still enforced. This method will best suit the social context of our country and is the considered opinion of the authors going forward. One disadvantage of this approach is that if the population is not managed well, people could travel to areas not under lock-down and re-start the epidemic cycle again. The need to therefore ensure enforcement is key to success in implementing this measure. Therefore current areas of Greater Accra and Kumasi that contribute to over 90% of Ghana’s case load should be made to adhere rigously to these measures.
What is the way forward?
As a nation grappling with the Covid-19 situation with lots of uncertainty surrounding it, all stakeholders particularly those tasked directly to bring it under control, should carefully implement the following strategies to prevent further virus spread. The following proposed interventions could be helpful in our war against this virus;1. Make a prediction of the trajectory of the disease and estimate the potential hotspots that need intervention. The estimates can be done using laboratory confirmed cases, estimated population with Covid-19 symptoms using mobile health technology, predictive mathematical models and spatial analysis of population movement and potential outbreak areas andestimation of the reproductive number of Covid-19 disease in Ghana,2. Develop a comprehensive list of all variables that would be needed to reduc the virus reproductive number ( R0)3. Perform a cost-benefit analysis of each intervention taking into account the nature of the variables we are dealing with.4. Rank the variables based on their cost-benefit analysis.5. Choose interventions that give the best reduction in R0but also at the lowest cost-the most cost effective.
What should Ghana do?
The Covid-19 epidemic is likely to stay with us for over year until a vaccine is made available to the entire population. It is therefore important that the decision to contain the virus spread should take into consideration the long-term objectives with minimal effect on the economy of the country. Epidemiological variables could be varied at different hotspots as and when it becomes necessary. Whether total or partial lockdowns are introduced or removed, it is important that some variables are held constant until the outbreak diminishes. The country should not make a mistake of lifting all restrictions at certain particular places until alternative adequate measures are put in place to monitor active case transmission and early detection of the virus. Some variables to consider in flattening the epidemic curve are;
Social Distancing Measuresa. Closure of borders to all affected countriesb. Suspension of conferences and workshops c. Suspension of sporting activitiesd. Implementing social distancing at market placese. Ban on gathering above a certain size carefully selected on the basis of science of transmissionf. Restricting travel to hotspots to restart new infections
Measures to reduce rate of infectiona. Enforcing the wearing of home-made masks by the general public.b. Enforcing disinfection of market places, commercialvehicles and vantage places where people usually visit.c. Embarking on aggressive education on handwashing and good hygienic practices.d. Decongesting and disinfecting slums and crowded places.e. Improving water supplies to all areas.f. Improving sanitary practices at all places.
Measures to enhance early detection of virusa. Establishing strategic PCR-based investigations at public health laboratories, regional medical laboratories,academic and government research institutions and veterinary laboratories.b. Evaluation and implementation of an early antigen rapid serological based test to support quick surveillance of populations and healthcare workers in high risk areas c. Enhancing community surveillance and testing of contacts and community spreaders using mobile based nucleic acid amplification tests. This could be installed in vans and ambulances and used in remote parts of Ghana.d. Establishing a system to prioritize testing for frontlinehealth workers who will be exposed in the line of duty.
Measures to enhance surveillancea. Establishing active surveillance of Covid-19 disease at all public and private hospitals, pharmacies, prayer camps, traditional healing camps and other possible places where sick individuals may attend for fear of stigmatization and discrimination.b. Developing mobile-phone based applications to support contact tracing and active surveillance of suspected and confirmed cases.c. Developing mobile applications that could pick up geographical locations of suspected cases and predict likely potential hotspots using GPS data points.d. Installing temperature check points at all vantage places.
Measures to engage communities effectivelya. Establishing systems that will bring onboard community leaders, household heads and local opinion leaders in education of the general public about this disease. This will enable the government to win the public trust in tacking the disease.b. Identifying underlying drivers of fear, anxiety and stigma that fuel misinformation and rumour, particularly through social media, and identifying and testing appropriate messages to support interventions
Measures to equip healthcare facilitiesc. A system must be established to ensure adequate supply of personal protective equipment to all health workers.d. Ghanaian companies must be adequately resourced and motivated to produce home-grown solutions such as the manufacture of ventilators for use by our health facilities.
It is our considered opinion that the suggested recommendations measures be carefully considered and implemented by Government officials and all relevant stakeholders in making key decisions about reducing the spread of Covid-19 disease. The lifting of restrictions should be done slowly and be replaced by alternative measures that will enhance surveillance and early detection of cases.
This article was authored by Michael Owusu, Augustina Sylverken, Sampson Twumasi-Ankrah, Richard Odame Phillips, Ellis Owusu-Dabo, Yaw Adu-Sarkodie.