Applying lessons from SARS to a newly identified coronavirus

Healthcare-Associated Infections (HAIs): Challenges and Measures Taken by the Radiology Department to Control Infection Transmission

Infections contracted during healthcare delivery in a hospital or ambulatory setting are collectively referred to as healthcare-associated infections (HAIs). Healthcare workers and patients alike are vulnerable to serious problems as a result of the risk of HAIs. In the healthcare system, HAIs are considered among the most common and serious health problems. However, the occurrence of HAIs differs between different types of clinical departments within the hospital. Recently, the risk of HAIs has been increasing in radiology departments globally due to the central role of radiology in guiding clinical decisions for the diagnosis, treatment, and monitoring of different diseases from almost all medical specialties. The radiology department is particularly vulnerable to HAIs because it serves as a transit hub for infected patients, non-infected patients, and healthcare workers. Furthermore, as the number of patients referred to radiology and the length of patient contact time has increased, thanks to modern imaging techniques such as computed tomography and magnetic resonance imaging, the risk of HAIs has also increased significantly. With the increasing use of interventional radiological procedures, patients and healthcare workers face a potentially greater risk of contracting HAIs due to the invasive nature of such procedures. Although not exhaustive, we attempted through a literature search to provide a general overview of infection prevention and control practices, address HAIs in the radiology departments, and highlight the challenges and measures taken to control infection transmission in the radiology departments.

Spatial pattern of severe acute respiratory syndrome in-out flow in 2003 in Mainland China

BACKGROUND

Severe acute respiratory syndrome (SARS) spread to 32 countries and regions within a few months in 2003. There were 5327 SARS cases from November 2002 to May 2003 in Mainland China, which involved 29 provinces, resulted in 349 deaths, and directly caused economic losses of $18.3 billion.

METHODS

This study used an in-out flow model and flow mapping to visualize and explore the spatial pattern of SARS transmission in different regions. In-out flow is measured by the in-out degree and clustering coefficient of SARS. Flow mapping is an exploratory method of spatial visualization for interaction data.

RESULTS

The findings were as follows. (1) SARS in-out flow had a clear hierarchy. It formed two main centers, Guangdong in South China and Beijing in North China, and two secondary centers, Shanxi and Inner Mongolia, both connected to Beijing. (2) "Spring Festival travel" strengthened external flow, but "SARS panic effect" played a more significant role and pushed the external flow to the peak. (3) External flow and its three typical kinds showed obvious spatial heterogeneity, such as self-spreading flow (spatial displacement of SARS cases only within the province or municipality of onset and medical locations); hospitalized flow (spatial displacement of SARS cases that had been seen by a hospital doctor); and migrant flow (spatial displacement of SARS cases among migrant workers). (4) Internal and external flow tended to occur in younger groups, and occupational differentiation was particularly evident. Low-income groups of male migrants aged 19-35 years were the main routes of external flow.

CONCLUSIONS

During 2002-2003, SARS in-out flow played an important role in countrywide transmission of the disease in Mainland China. The flow had obvious spatial heterogeneity, which was influenced by migrants' behavior characteristics. In addition, the Chinese holiday effect led to irregular spread of SARS, but the panic effect was more apparent in the middle and late stages of the epidemic. These findings constitute valuable input to prevent and control future serious infectious diseases like SARS.

Ribavirin and interferon alfa-2a for severe Middle East respiratory syndrome coronavirus infection: a retrospective cohort study

BACKGROUND

Middle East respiratory syndrome coronavirus (MERS-CoV) infection is associated with high mortality and has no approved antiviral therapy. We aimed to compare ribavirin and interferon alfa-2a treatment for patients with severe MERS-CoV infection with a supportive therapy only.

METHODS

In this retrospective cohort study, we included adults (aged ≥16 years) with laboratory-confirmed MERS-CoV infection and pneumonia needing ventilation support, diagnosed between Oct 23, 2012, and May 1, 2014, at the Prince Sultan Military Medical City (Riyadh, Saudi Arabia). All patients received appropriate supportive care and regular clinical and laboratory monitoring, but patients diagnosed after Sept 16, 2013, were also given oral ribavirin (dose based on calculated creatinine clearance, for 8-10 days) and subcutaneous pegylated interferon alfa-2a (180 μg per week for 2 weeks). The primary endpoint was 14-day and 28-day survival from the date of MERS-CoV infection diagnosis. We used χ(2) and Fischer's exact test to analyse categorical variables and the t test to analyse continuous variables.

FINDINGS

We analysed 20 patients who received ribavirin and interferon (treatment group; initiated a median of 3 days [range 0-8] after diagnosis) and 24 who did not (comparator group). Baseline clinical and laboratory characteristics were similar between groups, apart from baseline absolute neutrophil count, which was significantly lower in the comparator group (5·88 × 10(9)/L [SD 3·95] vs 9·88 × 10(9)/L [6·63]; p=0·023). 14 (70%) of 20 patients in the treatment group had survived after 14 days, compared with seven (29%) of 24 in the comparator group (p=0·004). After 28 days, six (30%) of 20 and four (17%) of 24, respectively, had survived (p=0·54). Adverse effects were similar between groups, apart from reduction in haemoglobin, which was significantly greater in the treatment group than in the comparator group (4·32 g/L [SD 2·47] vs 2·14 g/L [1·90]; p=0·002).

INTERPRETATION

In patients with severe MERS-CoV infection, ribavirin and interferon alfa-2a therapy is associated with significantly improved survival at 14 days, but not at 28 days. Further assessment in appropriately designed randomised trials is recommended.

FUNDING

None.

Clinical features and viral diagnosis of two cases of infection with Middle East Respiratory Syndrome coronavirus: a report of nosocomial transmission

BACKGROUND

Human infection with a novel coronavirus named Middle East Respiratory Syndrome coronavirus (MERS-CoV) was first identified in Saudi Arabia and the Middle East in September, 2012, with 44 laboratory-confirmed cases as of May 23, 2013. We report detailed clinical and virological data for two related cases of MERS-CoV disease, after nosocomial transmission of the virus from one patient to another in a French hospital.

METHODS

Patient 1 visited Dubai in April, 2013; patient 2 lives in France and did not travel abroad. Both patients had underlying immunosuppressive disorders. We tested specimens from the upper (nasopharyngeal swabs) or the lower (bronchoalveolar lavage, sputum) respiratory tract and whole blood, plasma, and serum specimens for MERS-CoV by real-time RT-PCR targeting the upE and Orf1A genes of MERS-CoV.

FINDINGS

Initial clinical presentation included fever, chills, and myalgia in both patients, and for patient 1, diarrhoea. Respiratory symptoms rapidly became predominant with acute respiratory failure leading to mechanical ventilation and extracorporeal membrane oxygenation (ECMO). Both patients developed acute renal failure. MERS-CoV was detected in lower respiratory tract specimens with high viral load (eg, cycle threshold [Ct] values of 22·9 for upE and 24 for Orf1a for a bronchoalveolar lavage sample from patient 1; Ct values of 22·5 for upE and 23·9 for Orf1a for an induced sputum sample from patient 2), whereas nasopharyngeal specimens were weakly positive or inconclusive. The two patients shared the same room for 3 days. The incubation period was estimated at 9-12 days for the second case. No secondary transmission was documented in hospital staff despite the absence of specific protective measures before the diagnosis of MERS-CoV was suspected. Patient 1 died on May 28, due to refractory multiple organ failure.

INTERPRETATION

Patients with respiratory symptoms returning from the Middle East or exposed to a confirmed case should be isolated and investigated for MERS-CoV with lower respiratory tract sample analysis and an assumed incubation period of 12 days. Immunosuppression should also be taken into account as a risk factor.

FUNDING

French Institute for Public Health Surveillance, ANR grant Labex Integrative Biology of Emerging Infectious Diseases, and the European Community's Seventh Framework Programme projects EMPERIE and PREDEMICS.

Transmission scenarios for Middle East Respiratory Syndrome Coronavirus (MERS-CoV) and how to tell them apart

Detection of human cases of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infection internationally is a global public health concern. Rigorous risk assessment is particularly challenging in a context where surveillance may be subject to under-ascertainment and a selection bias towards more severe cases. We would like to assess whether the virus is capable of causing widespread human epidemics, and whether self-sustaining transmission is already under way. Here we review possible transmission scenarios for MERS-CoV and their implications for risk assessment and control. We discuss how existing data, future investigations and analyses may help in reducing uncertainty and refining the public health risk assessment and present analytical approaches that allow robust assessment of epidemiological characteristics, even from partial and biased surveillance data. Finally, we urge that adequate data be collected on future cases to permit rigorous assessment of the transmission characteristics and severity of MERS-CoV, and the public health threat it may pose. Going beyond minimal case reporting, open international collaboration, under the guidance of the World Health Organization and the International Health Regulations, will impact on how this potential epidemic unfolds and prospects for control.