In one of the first reports of the clear risk of 2019 novel coronavirus (2019-nCoV) to healthcare workers (HCWs), an outbreak in a hospital in Wuhan, China, resulted in 40 infections in clinical staff caring for patients.1
In addition, about one-fourth of the HCWs contracted the coronavirus from a single patient. That transmission is reminiscent of the “super spreader” phenomenon seen with severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS).
“One patient in the current study presented with abdominal symptoms and was admitted to the surgical department,” researchers from Zhongnan Hospital of Wuhan University in Wuhan report. “More than 10 healthcare workers in this department were presumed to have been infected by this patient.”
Workers on general wards, in the emergency department, and in the intensive care unit also were infected while caring for patients from Jan. 1-28, 2020. The clinical outcomes for the HCWs were not reported in the paper. As of Jan. 21, 2020, the World Health Organization (WHO) reported that 16 HCWs had been infected by 2019-nCoV.2 No deaths were reported.
On Feb. 2, 2020, WHO reported: “In France, for the first time outside China, a healthcare worker was diagnosed as being ill with 2019-nCoV acute respiratory disease. The health worker treated two patients who were later identified as probable cases.”3
As this story was filed, no U.S. HCWs had been infected.
The rapidly emerging 2019-nCoV follows the SARS coronavirus outbreak in 2002-2003, which also emerged out of China, resulting in 8,098 infections globally and 774 deaths. Some of the SARS infections and deaths, particularly in hospitals in Toronto, were in HCWs.
The ongoing MERS outbreak centered in Saudi Arabia has been deadly to HCWs, but has not shown the ability to sustain spread to other countries. A recently published analysis4 of reported MERS cases between December 2016 and January 2019 revealed that 26% of 403 cases in the region were HCWs. The case fatality rate was a 16% among HCWs, compared to 34% among patients. Given these predecessors, the threat of 2019-nCoV to HCWs was a point of emphasis at a recent Centers for Disease Control and Prevention (CDC) press conference.
“This is a hugely important issue and the health of our healthcare workers is very important to all of us,” said Nancy Messonnier, MD, director of the CDC National Center for Respiratory Diseases. “We are being proactive at all levels to make sure that, as much as possible, the people taking care of [these patients] are careful and cautious.”
Part of this effort is prioritizing HCW exposures to cases of coronavirus being investigated, says Aron Hall, DVM, MSPH, epidemiology task force deputy lead for the CDC response to the outbreak. “For contact investigations, we are taking an approach that assesses the risk and tries to put people into different categories based on the presumed risk they may have had for exposures,” he said. “At the highest level of potential risks are certainly HCWs that had unprotected exposure to a confirmed case. It is a relatively similar level of risk as household contact or intimate partners of confirmed cases.”
Voice of Experience
To get some insight into this issue, Hospital Infection Control & Prevention interviewed Allison McGeer, MD, director of infection control at Mount Sinai Hospital in Toronto. McGeer dealt firsthand with the SARS outbreak in 2003, and has consulted on hospital outbreaks of MERS in Saudi Arabia.
HIC: What is your impression of the report from China of 40 HCWs being infected?
McGeer: It’s hard to tell a lot from one event. I think this hospital is one of the hospitals that has had more transmission to healthcare workers than others. The good news, relatively speaking, is that it remains clear that the proportion of cases in this outbreak that are healthcare workers is much smaller than SARS. It is not the same kind hospital issue that SARS was. This hospital appears to be the exception. The key issue is that healthcare workers are now protected because there are protocols in place. The risk of outbreaks of any infectious disease is always higher from unsuspected cases. At the beginning of an outbreak they are all unsuspected.
HIC: It appears at least 10 patients were infected by an unsuspected case.
McGeer: The challenge of this virus — if there is community spread — is that it is going to be much more difficult to separate [2019-nCoV] from everything else that causes fever and respiratory symptoms. That could present a very significant challenge to protecting healthcare workers. Say a case comes to a hospital — for a reason that is completely unrelated to novel coronavirus — but happens to be incubating it and develops illness in the hospital. Your go-to diagnosis in a post-op patient who develops fever is not novel coronavirus.
HIC: Having dealt with both SARS and MERS, can you comment on how this new 2019-nCoV compares to these other coronaviruses?
McGeer: It is very clear that the timing of when people are infectious with this coronavirus is different than SARS and MERS. With SARS and MERS, people are non-infectious before they have symptoms and non-infectious usually for the first few days of symptoms, and not as infectious if they don’t get severe illness. What that means is the time when people with SARS and MERS are most infectious is when they are more seriously ill, when they are admitted to hospitals, and particularly when they are admitted to intensive care units. SARS and MERS are viruses that primarily spread in hospitals. This new coronavirus is spreading more in the community. If you look at the numbers, in SARS, more than 20% of infections were in healthcare providers, and a substantial additional fraction were hospitalized patients and in visitors to hospitals. Most cases of SARS were associated with transmission in hospitals.
HIC: Other than this paper, there doesn’t seem to be as much reported spread to HCWs with this new coronavirus.
McGeer: Yes, though it is clear that there is some hospital transmission. It may be that hospital transmission [of 2019-nCoV] is like what we usually see, for instance, with things like influenza. There is some significant paranoia among some American commentators about the Chinese hiding things. The Chinese have been remarkably open and very quick to get at this. If this was like SARS and most of [the cases] were big hospital outbreaks, we would know about it. They are talking about all sorts of things so there would be no reason why they wouldn’t tell us if they were having large hospital outbreaks.
- Wang D, Hu B, Hu C, et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus–infected pneumonia in Wuhan, China. JAMA 2020; Feb. 7. [Online ahead of print].
- World Health Organization. Novel coronavirus (2019-nCoV) situation report – 2. Jan. 21, 2020. Available at: https://bit.ly/2u4UK7v. Accessed Feb. 6, 2020.
- World Health Organization. Novel coronavirus (2019-nCoV) situation report – 12. Feb. 1, 2020. Available at: https://bit.ly/2Ou5yTy. Accessed Feb. 6, 2020.
- Al-Tawfiq JA, Memish ZA. Middle East respiratory syndrome coronavirus in the last two years: Health care workers still at risk. Am J Infect Control 2019;47:1167-1170.