The spread of Middle East respiratory syndrome (MERS) to South Korea, and now to China, is an important signal of the need for increased vigilance in global health security measures. As reported in Correspondence in this week's issue, the rapid transmission of MERS in South Korea led to 12 laboratory-confirmed cases over a 2-week period in May, and many more cases since, with relatives, medical staff, and a fellow patient all contracting the disease, which started with one 68-year-old man who had travelled to the Middle East. The son of one of these South Korean patients, after visiting his father in hospital, then developed symptoms but nevertheless travelled into mainland China via Hong Kong. He is now in isolation with confirmed MERS in Huizhou, Guangdong province, and high-risk contacts are under surveillance.
This outbreak of MERS in Seoul is the largest case cluster outside the Middle East. Poor hospital infection control measures are likely to be important in the transmission of MERS here, as with previous outbreaks in Saudi Arabia. Lack of monitoring of close contacts for signs of infection, and prevention of travel to China, are other notable failures. With the exact mode of transmission and source of the MERS coronavirus still unknown, the development of treatments, let alone vaccines, remain a long way off, making prevention all the more important. The spectre of a previous coronavirus infection, which caused severe acute respiratory syndrome (SARS), still hangs over China, contributing to widespread concern and confusion about MERS now.
With new cases of Ebola still occurring in west Africa, frequent influenza epidemics worldwide, MERS (and previously SARS) adds to the infectious disease threat to global health security. As David Hui and colleagues call for in The Lancet Respiratory Medicine, we need “bold leadership…to generate the best evidence base for formulating effective public health, infection control and treatment interventions required to effectively tackle these infections”. Our global health security depends upon such leadership.
For more on MERS see Seminar Lancet 2015; published online June 3. http://dx.doi.org/10.1016/S0140-6736(15)60454-8
© 2015 Ami Images/Science Photo Library