Since the onset of the coronavirus disease 2019 (COVID-19) pandemic – caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) – the world has been plunged into economic and social crises on a scale unprecedented over the last century. However, this is the third pandemic in recent times caused by highly pathogenic coronaviruses.
A new paper published in the journal Medicine seeks to compare the current SARS-CoV-2 outbreak with the earlier SARS-CoV epidemic to understand the best way to respond to it sensitively and flexibly. This involves early detection, using multiple screening tests, followed by management of the clinical features as required, in order to prevent disease-related injury.
The period of maximum SARS-CoV-2 transmission is often the presymptomatic period, 48–72 hours prior to the clinical presentation. The increased contact with people during this period, and less attention to protective measures, due to lack of awareness of the presence of infectious disease, predisposes to a higher rate of spread at this time.
A novel mutation at the interface of the S1 and S2 subunits of the viral spike protein, introducing a furin cleavage site, makes the SARS-CoV-2 more infectious than the SARS-CoV, especially early in infection. A classic example is the occurrence of 621 cases onboard a cruise ship, the Diamond Princess, beginning with a single infected individual.
Transmission occurs via respiratory droplets, involving close contact between an index case and others. While the virus has been isolated from feces, the importance of urine and feces in transmission remains unclear.
SARS-CoV-2 was poised to cause a pandemic; that is, "states of an infectious disease that significantly increase in populations around the world with infections occur more or less simultaneously." While the earlier outbreak of SARS from Guangdong, China, involved just over 8,400 people in 25 countries or regions of the world, the currently circulating virus has caused over 109 million cases, with more than 2.4 million deaths, involving 192 countries and territories worldwide.
SARS-CoV-2 appears to be set to linger in the world for a longer period than the SARS outbreak that settled in seven months. More than a year after the first case was reported, infection rates continue to be high in many regions of the world.
An unusual feature of the COVID-19 pandemic is how its epicenter keeps shifting, from China's Wuhan to other countries in Asia, as well as to Europe, and then to the US and Australia.
While the Chinese economy accounted for only 4% of the global economy back in 2002, during the SARS epidemic, it now makes up 17%, as the second-ranked world economy. However, it has been affected severely by the current pandemic, raising the possibility of hitting a nadir not seen in the last three decades.
In the UK, universal credit was expected to be required by 3.5 million more people than before. US stocks are at the lowest point since 1987, with a ricochet effect on 11 other countries and regions. China being the biggest manufacturer and crude oil importer, its economic downturn is bound to set off a global recession as well.
Preventive and therapeutic measures
The mainstay of COVID-19 containment was preventive non-pharmaceutical interventions, including social distancing, scrupulous regular handwashing after possible contact with contaminated surfaces, surface disinfection, wearing masks when in public spaces, and self-isolation for contacts of infected individuals.
The Chinese health authorities have set forth a manual on COVID-19 epidemiology, signs and symptoms, clinical grading, and treatment, as well as distinguishing features between COVID-19 and other upper respiratory infections or flu-like illnesses.
This document, "Chinese Clinical Guidance for COVID-19 Pneumonia Diagnosis and Treatment," also helps to identify cases and notify the relevant authorities, in addition to the right management in all grades of severity. Criteria for discharge and follow-up are also outlined, as well as precautions to prevent the dissemination of the infection.
Chinese management of COVID-19
In contrast to the delayed awareness of the SARS outbreak, which led to misinformation and panic buying, the current pandemic was characterized by a more rapid response with greater transparency. Immediately after the identification of the first case of unknown pneumonia in Wuhan, China, in December 2019, appropriate epidemiological measures were set up.
Virus samples were taken, the epidemiological trail was investigated, and guidelines on therapy, were released within 45 days of the first case, and a rapid response was initiated. "Eight rumor-mongers were dealt with according to the law," the report says. A database was set up within a year of the first case in China.
Rapid development of testing kits
Testing kits were rapidly manufactured and marketed by the Chinese National Medical Products Administration (NMPA), with adequate efficiency and sensitivity. An acceptable polymerase chain reaction (PCR) test was made available only ten months after the first case of SARS, in the last outbreak in 2003.
In contrast, NMPA's emergency protocol brought a reverse transcription-polymerase chain reaction (RT-PCR) testing kit to the market within two weeks. With the incorporation of Real-Time Fluorescent RT-PCR test, it became possible to get the test results within three hours.
Another innovation was the mobile emergency hospital, built on a large scale to treat and follow up less sick patients, reserving the main hospitals for severe COVID-19 patients. Dating from the 1960s, this concept offers medical and technological support on a platform that allows rapid deployment where required.
Though the concept originated in Vietnam, with the US military, it was adopted for disaster situations and military operations not involving war. In the current situation, the government took over sports and exhibition halls and schools for mobile hospitals. The Wuhan outbreak was successfully contained in less than three months.
From the onset of the pandemic to March 10th, 2020, mobile emergency hospitals were set up to treat over 12,000 patients, and dismantled, having fulfilled their purpose. This is in contrast to the less than 700 cases of SARS that were treated in 2003.
Lockdown in China
SARS-CoV-2 triggered the first lockdown in over 70 years in China, involving 16 cities. The pandemic appeared near the time of the Spring Festival, where almost 3 billion visits were made to meet one's family, typically at their hometown. This comes to about 70 million trips a day over 40 days of the festival-related holiday season.
In view of the estimated spread of the virus to over 50% of the population in nearly 370 other cities in China, from Wuhan, and almost the whole population of the four largest metropolises, the authorities clamped down on public transport by road, rail, subway and air, to and from 16 cities.
A chain of command was set up to coordinate the Chinese response to COVID-19. Local governments took their cue from the special command group of the Chinese National Health Commission. They, in turn, briefed district governments on the required arrangements.
Community leaders and volunteers helped to execute the containment measures, from checking temperatures to isolating patients, and from delivering food to translating for foreigners.
The biocontainer approach used by the US government will help protect people traveling back to China from overseas from the infection until they can reach the right center for treatment.
Accident insurance for medical workers
Though medical workers were not reimbursed by insurance for the risks they ran during the SARS outbreak, the current pandemic saw temporary work subsidies and increased subsidies for preventive health and epidemic containment work. Over 20 insurance firms in China donated substantial amounts of insurance to frontline medical workers, over and above government subsidies.
Military and volunteer cooperation
Military-style management of a huge corps of student volunteers helped contain the pandemic, compared to the earlier outbreak of SARS. Over 30,000 volunteers have been engaged in COVID-19 quarantine and prevention work, for a total of over 18 million hours.
What are the implications?
The report commends China's efforts to contain the outbreak within its border by its "rigorous containment and quarantine efforts," citing these as responsible for China's emergence from the active phase of the pandemic, earliest among the world's countries.
However, notification of the Chinese Center for Disease Control occurred nearly two months after the first case of novel pneumonia, delaying the opportunity to clamp down on viral spread early in the course of the outbreak. This was a failure of the surveillance system introduced after the SARS outbreak.
Thirdly, the preparedness level in terms of personal protective equipment (PPE) and other aids was too low, with most hospitals keeping only a month's stock on hand. This led to an initial severe shortage of medical supplies required to deal with the virus's spread and its treatment.
The process of distributing PPE from the centers where it arrived was often hampered by bureaucratic procedures, leading to local shortages despite its supply from the national stockpile. Some medical workers were also unnecessarily exposed to the virus as a result.
The researchers aim to disseminate their newly developed early warning mechanism for future pandemics, and to address the deficiencies observed in local logistic units, allowing multi-channel distribution in case of emergency while maintaining adequate stockpiles.