Africa becomes WHO priority in fight against fast-spreading coronavirus

The likelihood of a coronavirus outbreak in Africa was “very, very high”, the World Health Organisation warns, as cases of the respiratory illness soar past the 20,000 mark, writes MedicalbriefSouth Africa along with 12 other African countries have been prioritised for screening because of their direct links with China.

The Guardian newspaper is providing live updates on the fast-spreading coronavirus.

The WHO is scaling up novel coronavirus preparedness efforts in the African region and supporting countries to implement recommendations outlined by the International Health Regulations Emergency Committee, which met in Geneva, Switzerland on 30 January. On the advice of the Emergency Committee, the WHO director-general declared the novel coronavirus outbreak a public health emergency of international concern (PHEIC).

The Emergency Committee recommends that all countries should be prepared for containment, including active surveillance, early detection, isolation and case management, contact tracing and prevention of onward spread of novel coronavirus or 2019-nCoV infection, and to share full data with WHO.

While WHO is supporting countries to investigate a number of alerts, there continues to be no reported cases of the novel coronavirus in the African region. However, there are many links between China and the African continent.

Dr Matshidiso Moeti, WHO regional director for Africa, has sent out a guidance note to all countries on how to prepare for a possible novel coronavirus outbreak.

“It is critical that countries step up their readiness and in particular put in place effective screening mechanisms at airports and other major points of entry to ensure that the first cases are detected quickly,” said Moeti. “The quicker countries can detect cases, the faster they will be able to contain an outbreak and ensure the novel coronavirus does not overwhelm health systems.”

Rapid confirmation or ruling out novel coronavirus cases, establishing a platform for isolating suspected or confirmed cases, getting good information out to the public and pre-positioning supplies are all important actions for countries to undertake.

WHO has identified 13 top priority countries (Algeria, Angola, Cote d’Ivoire, the Democratic Republic of the Congo, Ethiopia, Ghana, Kenya, Mauritius, Nigeria, South Africa, Tanzania, Uganda and Zambia) which either have direct links or a high volume of travel to China.

Active screening at airports has been established in a majority of these countries and while they will be WHO first areas of focus, the organization will support all countries in the region in their preparation efforts.

Amid the mounting concerns, medical experts appear certain that the deadly virus will also infect people on the continent, pointing to the deepening trade and travel ties between China and Africa that has seen many countries on the continent become popular tourist, business and investment destinations for the Chinese.

“We can be very certain that coronavirus will be exported to Africa,” Ngozi Erondu, associate fellow of the Global Health Programme at Chatham House is quoted in a News24 report as saying. “There is a large amount of travel between China and Africa; hubs such as Addis Ababa, Cairo and Nairobi are at particular risks due to the large amount of Chinese travellers that pass through these airports.”

Speaking at the African Union headquarters, John Nkengasong, director of the Africa Centres for Disease Control and Preventions (Africa CDC), said the institution was working closely with their Chinese counterparts, adding that, “We in Africa are watching the situation and also preparing ourselves to deal with any outbreak or cases.”

China’s ambassador in South Africa Lin Songtian says measures are in place to ensure that suspected cases of the deadly coronavirus on the continent do not spread to South Africa. “My eye is open on the continent, South Africa and China have been in contact and I assure you there are measures in place to ensure that the virus does not cross the border.”

Polity reports that Songtian was responding to a query on the suspected case of the coronavirus in Botswana, which borders South Africa. It was reported on Friday of last week that Botswana had registered its first suspected case of the coronavirus at Gaborone‘s Sir Seretse Khama International Airport. This comes after a passenger travelling from China arrived at the airport on an Ethiopian Airways flight.

To date, there is no confirmed case of the virus in the country, but South Africa remains on high alert. While Songtian could not confirm how many Chinese nationals were currently in South Africa, he clarified that those who travelled to China for the holidays had been requested “to stay there for now”.

Transnet is implementing strict health measures and extra procedures for all vessels entering South Africa’s ports to prevent the potential spread of coronavirus, reports The Times. Port health employees have been sensitised to government’s national response plan to diagnose infected people and refer them to designated sites or hospitals, Transnet SOC Ltd said.

Transnet is the custodian of the ports, rail and pipeline infrastructure in South Africa. Transnet said it was working with the department of health and National Institute of Communicable Diseases (NICD) to monitor the outbreak.

J Stephen Morrison, director of the Global Health Policy Centre at the Centre for Strategic and International Studies in Washington, said the disease risked taking root if it reaches certain African countries. According to a report in The Times, he warned that such a scenario could usher in a “global pandemic”.

Several poor African states have recently suffered disastrous viral outbreaks – and the report says, they’re keenly aware of the coronavirus outbreak threat. The Ebola virus raged through Liberia, Sierra Leone and Guinea in 2014-2016, killing about 11,300 people.

Mosoka Fallah, the head of Liberia’s public health institute, is quoted in the report as saying that the rapid spread of the new coronavirus was “catastrophic”. “Steps must be taken as early as possible to prevent it from entering here,” he said, adding that the government had ramped up airport checks.

Academic, former MP and Democratic Alliance spokesperson for health, Wilmot James, who has edited a new book on South Africa’s health security, said the 2019 novel coronavirus was overwhelming hospitals in China and the South African system was “weaker and far less accessible to the majority of our population compared to China’s”, reports The Times.

The national Health Department has appointed Grey’s Hospital in Pietermaritzburg to manage any suspected coronavirus cases in KwaZulu-Natal, but health professionals there said they had not received training in handling or treating patients with the deadly virus. A Sunday Tribune report notes that during a press conference to allay fears in the country, Minister of Health Dr Zweli Mkhize said although appointed hospitals were understaffed and had equipment shortages, all had specialised units which could handle potential cases.

The report says a visit to Grey’s after the announcement, to check its level of readiness, found there were no awareness posters and some nurses were not clear on what 2019-ncov was, of its symptoms or who stood to be at risk. Paramedics in a state ambulance in the hospital’s parking lot said they had not received any special training.

A nurse said since the beginning of the outbreak, hospital management had not sent out any communiqué about the coronavirus. She said she was not aware that she would be required to handle a patient diagnosed with the virus should deadly disease make its way to the province. “None of us have been told anything about the virus and its spread,” she said. “Management has not prepared us in any way.”

KZN Health spokesperson Agiza Hlongwane, said there were no confirmed cases in the country and the Sunday Tribune’s questions were causing unnecessary panic. “Grey’s Hospital is a tertiary level health care facility with some of the best specialists, equipment and facilities in the country and continent,” said Hlongwane.

Hundreds of hospital workers in Hong Kong have gone on strike, demanding the border with mainland China be completely closed to reduce the risk of the coronavirus spreading. There have been 15 confirmed cases of the virus in the city.According to a BBC News report, Hong Kong has suspended cross-border rail and ferry services, but health workers want a total border closure.

But, the report says, authorities say closing the border completely would go against advice from the WHO.

As well as transportation closures, China has also stopped issuing visas for individual travellers to Hong Kong.

Meanwhile, new modelling research estimates that up to 75,800 individuals in the Chinese city of Wuhan may have been infected with 2019 novel coronavirus (2019-nCoV) as of 25 January, 2020. Senior author Professor Gabriel Leung from the University of Hong Kong highlights: “Not everyone who is infected with 2019-nCoV would require or seek medical attention. During the urgent demands of a rapidly expanding epidemic of a completely new virus, especially when system capacity is getting overwhelmed, some of those infected may be under-counted in the official register.”

He explains: “The apparent discrepancy between our modelled estimates of 2019-nCoV infections and the actual number of confirmed cases in Wuhan could also be due to several other factors. These include that there is a time lag between infection and symptom onset, delays in infected persons coming to medical attention, and time taken to confirm cases by laboratory testing, which could all affect overall recording and reporting.”

The new estimates also suggest that multiple major Chinese cities might have already imported dozens of cases of 2019-nCoV infection from Wuhan, in numbers sufficient to initiate local epidemics.

The early estimates underscore that it will likely take rapid and immediate scale-up of substantial public health control measures to prevent large epidemics in areas outside Wuhan. Further analyses suggest that if transmissibility of 2019-nCoV could be reduced, both the growth rate and size of local epidemics in all cities across China could be reduced.

“If the transmissibility of 2019-nCoV is similar nationally and over time, it is possible that epidemics could be already growing in multiple major Chinese cities, with a time lag of one to two weeks behind the Wuhan outbreak,” says lead author Professor Joseph Wu from the University of Hong Kong. “Large cities overseas with close transport links to China could potentially also become outbreak epicentres because of substantial spread of pre-symptomatic cases unless substantial public health interventions at both the population and personal levels are implemented immediately.”

According to Leung: “Based on our estimates, we would strongly urge authorities worldwide that preparedness plans and mitigation interventions should be readied for quick deployment, including securing supplies of test reagents, drugs, personal protective equipment, hospital supplies, and above all human resources, especially in cities with close ties with Wuhan and other major Chinese cities.”

In the study, researchers used mathematical modelling to estimate the size of the epidemic based on officially reported 2019-nCoV case data and domestic and international travel (train, air, road) data. They assumed that the serial interval estimate (the time it takes for infected individuals to infect other people) for 2019-nCoV was the same as for severe acute respiratory syndrome (SARS: table 1). The researchers also modelled potential future spread of 2019-nCoV in China and internationally, accounting for the potential impact of various public health interventions that were implemented in January 2020 including use of face masks and increased personal hygiene, and the quarantine measures introduced in Wuhan on 23 January.

The researchers estimate that in the early stages of the Wuhan outbreak (from 1 December, 2019 to 25 January, 2020) each person infected with 2019-nCoV could have infected up to 2-3 other individuals on average, and that the epidemic doubled in size every 6.4 days. During this period, up to 75,815 individuals could have been infected in Wuhan.

Additionally, estimates suggest that cases of 2019-nCoV infection may have spread from Wuhan to multiple other major Chinese cities as of 25 January, including Guangzhou (111 cases), Beijing (113), Shanghai (98), and Shenzhen (80; figure 3). Together these cities account for over half of all outbound international air travel from China.

While the estimates suggest that the quarantine in Wuhan may not have the intended effect of completely halting the epidemic, further analyses suggest that if transmissibility of 2019-nCoV could be reduced by 25% in all cities nationally with expanded control efforts, both the growth rate and size of local epidemics could be substantially reduced.

Moreover, a 50% reduction in transmissibility could shift the current 2019-nCoV epidemic from one that is expanding rapidly, to one that is slowly growing (figure 4). “It might be possible to reduce local transmissibility and contain local epidemics if substantial, even draconian, measures that limit population mobility in all affected areas are immediately considered. Precisely what and how much should be done is highly contextually specific and there is no one-size-fits-all set of prescriptive interventions that would be appropriate across all settings,” says co-author Dr Kathy Leung from the University of Hong Kong. “On top of that, strategies to drastically reduce within-population contact by cancelling mass gatherings, school closures, and introducing work-from-home arrangements could contain the spread of infection so that the first imported cases, or even early local transmission, does not result in large epidemics outside Wuhan.”

The authors point to several limitations of their study, including that the accuracy of their estimates depend on their assumption about the zoonotic source of infection in Wuhan. They also highlight that the models assume travel behaviour was not affected by disease status and that all infections eventually have symptoms – so it is possible that milder cases have gone undetected which could underestimate the size of the outbreak. Lastly, they note that their epidemic forecast was based on inter-city mobility data from 2019, and might not reflect mobility patterns in 2020, particularly in light of the health threat posed by 2019-nCoV.

Abstract
Background: Since Dec 31, 2019, the Chinese city of Wuhan has reported an outbreak of atypical pneumonia caused by the 2019 novel coronavirus (2019-nCoV). Cases have been exported to other Chinese cities, as well as internationally, threatening to trigger a global outbreak. Here, we provide an estimate of the size of the epidemic in Wuhan on the basis of the number of cases exported from Wuhan to cities outside mainland China and forecast the extent of the domestic and global public health risks of epidemics, accounting for social and non-pharmaceutical prevention interventions.

Methods: We used data from Dec 31, 2019, to Jan 28, 2020, on the number of cases exported from Wuhan internationally (known days of symptom onset from Dec 25, 2019, to Jan 19, 2020) to infer the number of infections in Wuhan from Dec 1, 2019, to Jan 25, 2020. Cases exported domestically were then estimated. We forecasted the national and global spread of 2019-nCoV, accounting for the effect of the metropolitan-wide quarantine of Wuhan and surrounding cities, which began Jan 23–24, 2020. We used data on monthly flight bookings from the Official Aviation Guide and data on human mobility across more than 300 prefecture-level cities in mainland China from the Tencent database. Data on confirmed cases were obtained from the reports published by the Chinese Center for Disease Control and Prevention. Serial interval estimates were based on previous studies of severe acute respiratory syndrome coronavirus (SARS-CoV). A susceptible-exposed-infectious-recovered metapopulation model was used to simulate the epidemics across all major cities in China. The basic reproductive number was estimated using Markov Chain Monte Carlo methods and presented using the resulting posterior mean and 95% credibile interval (CrI).
Findings: In our baseline scenario, we estimated that the basic reproductive number for 2019-nCoV was 2·68 (95% CrI 2·47–2·86) and that 75 815 individuals (95% CrI 37 304–130 330) have been infected in Wuhan as of Jan 25, 2020. The epidemic doubling time was 6·4 days (95% CrI 5·8–7·1). We estimated that in the baseline scenario, Chongqing, Beijing, Shanghai, Guangzhou, and Shenzhen had imported 461 (95% CrI 227–805), 113 (57–193), 98 (49–168), 111 (56–191), and 80 (40–139) infections from Wuhan, respectively. If the transmissibility of 2019-nCoV were similar everywhere domestically and over time, we inferred that epidemics are already growing exponentially in multiple major cities of China with a lag time behind the Wuhan outbreak of about 1–2 weeks.
Interpretation: Given that 2019-nCoV is no longer contained within Wuhan, other major Chinese cities are probably sustaining localised outbreaks. Large cities overseas with close transport links to China could also become outbreak epicentres, unless substantial public health interventions at both the population and personal levels are implemented immediately. Independent self-sustaining outbreaks in major cities globally could become inevitable because of substantial exportation of presymptomatic cases and in the absence of large-scale public health interventions. Preparedness plans and mitigation interventions should be readied for quick deployment globally.
Funding: Health and Medical Research Fund (Hong Kong, China).

Authors
Joseph T Wu, Kathy Leung, Gabriel M Leung

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