We need more data to prepare for the new coronavirus outbreak
In the six weeks since an outbreak of a novel coronavirus was first recognized in Wuhan, China, scientific discovery has unfolded at an unprecedented rate. Genomes of 73 samples of the virus, known for now as 2019-nCoV, from 12 countries have already been published, as have at least five academic papers describing clinical and epidemiological features of the disease.
Despite these efforts, there are critical information gaps that make planning for the outbreak more challenging and uncertain. In addition to a better understanding of severity and case fatality, as well as rigorous examination of the mechanisms by which the virus spreads (all of which have been called for elsewhere), we see three other urgent priorities: understanding health care worker infections, understanding the circumstances around deaths from these coronavirus infections, and the surveillance strategy for 2019-nCoV across China.
Health care worker infections
During infectious disease outbreaks, understanding whether and how health care workers become infected while caring for patients is key. That information provides a picture of how transmissible an infectious disease is and how effectively it can spread within health care institutions.
When health care infections happen early in an outbreak, it indicates that engineering controls, administrative controls, personal protective equipment, and other preventive measures were not yet in place to keep workers protected. But if these infections continue to happen as an outbreak evolves, it suggests that the workers are not wearing the necessary protective equipment or aren’t wearing it in the right way, or that controls are otherwise unsuccessful. These lessons can help others avoid making the same mistakes and are vital for protecting health care professionals across the rest of China and around the world.
A recent paper in the Journal of the American Medical Association provides some information on 40 health-care-associated coronavirus infections in China, which was the first indication that transmission in hospitals is common. But that information comes from just a single hospital in Wuhan, and there are more than two dozen facilities in the province currently treating coronavirus patients. The paper did not give details about when or how the workers were infected, leaving many questions about what other health care workers should do differently to stay safe.
One example of the kind of information that would help hospitals prepare is a study from Abu Dhabi that carefully investigated clusters of health care workers infected with the coronavirus that causes Middle East respiratory syndrome (MERS). The paper describes in detail the circumstances, outcomes, and clinical course of infected workers. With similar data on 2019-nCoV, hospitals could act now to keep their personnel safe while treating coronavirus patients.
Clinical details surrounding coronavirus deaths
As of Feb. 9, China has reported 908 deaths from 2019-nCoV, more deaths than were caused by severe acute respiratory syndrome (SARS). Although some details on a small number of deaths have been provided in clinical case series published in top academic journals, more data are needed.
Governments, public health authorities, clinicians, and hospitals trying to prevent deaths from 2019-nCoV would benefit from knowing, for example, what was the time elapsed between the first appearance of symptoms and the time of death? What percentage of deaths occurred due to resource constraints, such the lack of availability of mechanical ventilators or high-flow oxygen? What percentage occurred despite access to mechanical ventilation? What percentage occurred because of co-infection or some other disease mechanism? Are there any early symptoms or indicators of a poor outcome?
A paper describing SARS-related deaths provides some of that kind of clinical information that would be useful if collected for 2019-nCoV. Given the extraordinary pressures related to patient care in Wuhan, it may be that such information will be difficult to write up in a scientific paper in that detail in the near term. If that is the case, it would be valuable to present it in more informal ways.
Surveillance approach in China
It is clear from daily situation reports published by China’s National Health Commission that 2,000-3,000 new cases of 2019-nCoV are reported each day, mostly in Hubei province. What isn’t clear is how that number fits into the overall diagnostic testing strategy for this coronavirus. It would be valuable to learn how many diagnostic tests are being done each day in China, what percentage of them are positive and negative, and what’s the backlog for testing, if any. Given emerging reports that the current tests have poor sensitivity, it would also be useful to know how many people with early negative test results then go on to test positive for the coronavirus.
It is also important to understand the criteria for diagnostic testing across China. Outside of Hubei province, are only people with a relevant travel or contact history being tested, or have the testing criteria been expanded? Is any diagnostic testing being done on people with mild respiratory symptoms, perhaps through sentinel surveillance? Are any serosurveys underway?
This information would facilitate a better understanding of the true burden of 2019-nCoV. It would also help inform our understanding of the pathogen’s overall severity, which is needed to assess the outbreak’s impact and to gauge how to respond. SARS, with a mortality rate around 10%, falls on the high end of the coronavirus spectrum of severity, while the seasonal coronaviruses we live with every winter fall on the low end, causing mostly mild illness. We do not yet have a clear picture of where 2019-nCoV sits on this spectrum.
Information that yields a greater understanding of the severity of 2019-nCoV, its risk factors, capacity to cause health care worker infections, mechanism of death, and China’s surveillance strategy would be of great value to those preparing for and responding to this disease around the world. Governments, ministries of health, hospitals, and clinicians could improve their efforts to slow the spread of the virus, care for those infected with it, and protect both the public health and the health care work force in response to 2019-nCoV.
Caitlin M. Rivers, Ph.D., is a senior scholar at the Johns Hopkins Center for Health Security and assistant professor in the Department of Environmental Health and Engineering at Johns Hopkins University. Tom Inglesby, M.D., is director of the Johns Hopkins Center for Health Security and professor in the Department of Environmental Health and Engineering at Johns Hopkins Bloomberg School of Public Health.