What are the risks posed by coronaviruses to health, and what are the implications of WHO’s decision for Mauritius and the rest of Africa?
By Dr Deoraj Caussy
Integrated Epidemiology Solution
China is currently reeling under an unprecedented coronavirus epidemic of biblical magnitude which has sent the authorities scrambling for effective public health measures to curtail and contain the epidemic. In view of this, the World Health Organization (WHO) whose remit is global health security, convened a meeting in January 2020 to assess the situation and, sadly enough, concluded that at this point it is a national emergency only for China. This begs the questions as to why that decision was made, what are the risks posed by coronaviruses to health, and what are the implications of WHO’s decision for Mauritius and the rest of Africa?
What are the coronaviruses?
The family of coronaviruses is a diverse group of viruses, comprising many members that can infect both animals and humans. Human coronaviruses often originate from animal reservoirs, crossing the species barriers to infect humans. Three notorious members in this family that have caused severe human illness and deaths include the SARS (Severe Acute Respiratory Syndrome), MERS-CoV (Middle East Respiratory Syndrome Coronavirus) and the recent novel virus (2019-n-CoV) from China.
– SARS-CoV is transmitted from civet cats to humans and was first noted in China.
– MERS-CoV is transmitted from dromedary camels to humans and was first detected in Saudi Arabia.
– The current novel coronavirus, that was first reported in Wuhan in mid-December 2019, is likely to have emerged from a virus related to bat coronaviruses and the SARS coronavirus.
This novel coronavirus is of particular concern since it resembles the SARS coronavirus. Information about the novel coronavirus is that evolving as the epidemic unfolds; we already know that it has passed from wild animals to humans (first highlighted in a cluster of cases from a seafood market), adapted to humans and is readily transmitted from person to person. The number of reported persons infected in China, according to latest figures, would stand at around 7700 cases, with 170 deaths, but these figures must be taken with some reservations since they are subject to reporting delays and the numbers will go up as surveillance and testing are stepped up. Furthermore, based on extrapolation from the SARS epidemic, it is believed that some 7% of the cases might die in the absence of treatment.
Sharing information and taking control measures
Contrary to the previous Chinese delay in reporting the SARS outbreak to the WHO, it has this time round acknowledged the existence of the 2019-n-CoV, shared the information with the global community, and taken drastic steps to curtail the epidemic. On the public health front, China has implemented heroic measures that may yet prove to be feeble, as they have been initiated too late. The focus is on eliminating the source of infection by isolating the cases. This measure would have been effective at the outset of the epidemic; the daily increasing number of cases shows that the virus is well seeded in the population.
Besides, there are other caveats, from a public health point of view, that pose immediate challenges to controlling the epidemic in China or elsewhere for that matter. The concerns centre on two main issues: when is a person infective, and do all infected persons show definitive clinical signs of the disease? Firstly, according to Chinese officials, a person can shed the virus well before he develops clear signs and unwittingly transmits it. Secondly, not all infected persons develop the disease, although they shed the virus, and thus represent an infected pool of carriers that infect other persons.
To complicate the situation, presently it is the influenza season in China, making it difficult to distinguish between the two diseases. If one mistakenly brings together an influenza patient with coronavirus patients, one runs the risk of spreading the infections further.
WHO and global health security
The WHO was established shortly after the World Wars to ensure global health security. This is a tall mandate and WHO has constantly kept up with the best possible approach by regularly incorporating new information while formulating global guidance. Thus, global disease surveillance has evolved from initially focusing on four diseases (smallpox, yellow fever, plague and cholera) under the old sanitary regulations to detecting any event that represents a global threat, embodied in the updated version of International Health Regulations (2005).
Under the IHR, an event or disease is classified as posing an international threat if a panel of experts establishes that it meets any two of the following objective criteria: 1) it is a novel event, 2) it is causing significant disease and mortality, 3) it can spread to other countries, and 4) it can interfere with trade and travel. Since the adoption of these criteria, WHO has classified five previous outbreaks as public health emergencies of international concern.
There has been much debate about the application of IHR: for instance, WHO has been criticised for being too quick to declare an international emergency – as in the case of 2009 influenza pandemic, and 2017 ZIKA outbreaks. On the other hand, WHO has also been reprimanded for being too slow to declare an international emergency for the 2015 epidemic of Ebola in West Africa. The outcome of the WHO committee on the novel coronavirus last week was a split decision and the Director General held off declaring an international emergency.
If a panel of experts using the same objective criteria are split, what does this say about the process of decision making by WHO? The forerunner of IHR was used by WHO to impose a travel ban in and out of Toronto during the 2003 SARS outbreak because 40 deaths occurred and the infection rate was not coming down. Now that we have a full-fledged IHR backed by objective criteria, why cannot we apply the same principle?
This is an international concern and not just a national Chinese one: the virus has already appeared in many parts of the world, and with the amount of trade and commerce combined with travel, it is bound to enter the developing countries including Africa. Developed countries have the infrastructure, resilient health systems and manpower to detect, curtail and ward off the virus. What can developing countries, including Mauritius, do?
Options for prevention of infection by coronavirus
We have three basic control options left to us: screen at point of entry, test for the virus, and isolate infected cases. All these options are presently flawed or inadequate. Screening, consisting of taking temperature and noting clinical signs, is of limited value as indicated earlier since not all patients will have fever. As for the second option – testing for the virus -, unfortunately we cannot currently do so locally. It is paradoxical and patently incorrect to tell the Mauritian population that there is zero case of novel coronavirus in Mauritius, when we have not even tested for it.
Isolation remains our best third option, but we have an isolation facility that worked in the 20th century for the management of malaria, dengue, cholera, etc. It is inadequate for 21st century challenges for management of emerging diseases caused by coronavirus, Ebola virus and other pathogens that require universal precautions as they can be transmitted by a variety of modalities including air droplets, breathing, direct and indirect contacts. Modern negative pressure wards are constructed, monitored, validated and maintained by professional biomedical engineers in accordance with international biosafety and biosecurity standards. Our improvised isolation ward is a fly-by-night construction and to date has never managed a confirmed case of Ebola, MERS, or SARS. The ministry of Health has recognized this shortcoming and listed it in the planned budget for a while now, but this has not seen the light of day. Is it not high time to build our capacity?
To avert SARS importation in 2003, Mauritius suspended all flights from Singapore. Are we willing to take a similar bold measure with flights from China, or are we so economically tied with China that we falter in protecting the health of the nation? It may be argued that in its decision not to declare an international emergency, WHO prostrated to China for economic reasons and quivers to ensure global health security.
The most vulnerable sector in the community with regard to all these three notorious coronaviruses are the health care workers. Under the best of circumstances, hospital acquired infections are common in our setting; now imagine compounding this situation with a lethal coronavirus that spreads quickly in healthcare settings. It is imperative to protect our health care personnel against this novel coronavirus or other emerging pathogens because the cost of inaction may be more than the cost of delayed corrective actions.
One may ask: what is the responsibility of China to protect the world from the novel coronavirus infection? China has made substantial health commitments to health in Africa in the past several decades. It was one of the first countries to provide technical assistance in the West African Ebola crisis of 2015 and has contributed to designing the African Centres for Disease Control. There is a dearth of reported cases of novel coronavirus in Africa, underscoring the capacities of these countries to test for this virus. Will China bridge this gap, or will China’s health assistance to Africa be opportunistic rather than altruistic, as argued by some?
* Published in print edition on 31 January 2020