Possible Pandemic: Is MERS the new SARS?

Melody Kramer

National Geographic

Published May 30, 2013

A 65-year-old man infected with a new SARS-like virus died of multiple organ failure on Monday in France.

He was the first French patient to die from the condition, which is known as Middle East Respiratory Symptom Coronavirus, or MERS-CoV. As of Wednesday, 49 people have been infected with the virus since September; of those, 27 have died.

The French man, who remains unidentified, was hospitalized in Lille last month, after returning from a vacation in Dubai, where it is believed he was infected. Another patient in France was in stable but very serious condition.

Dr. Margaret Chan, the director-general of the United Nation's World Health Organization, called the virus a "threat to the entire world" on Monday at the annual World Health Assembly in Geneva, Switzerland.

"It is not a problem that any single affected country can keep to itself or manage all by itself," she said. "We do not know where the virus hides in nature. We do not know how people are getting infected. Until we answer these questions, we are empty-handed when it comes to prevention. These are alarm bells. And we must respond."

Part of what worries global health officials about MERS-CoV is how rapidly it seems to be spreading around the globe. Most of the confirmed cases of the virus have originated in Saudi Arabia, but cases have also been reported in France, Germany, Qatar, Jordan, and Britain.

Does modern life make us more susceptible to modern pandemics? We asked virologist Nathan Wolfe, author of The Viral Storm and a National Geographic Emerging Explorer, to explain what we know and don't know about this deadly new virus. Wolfe, the founder and executive chair of Global Viral and a visiting professor at Stanford University, is working to create an early-warning system to forecast and contain new viruses before they turn into deadly pandemics.

This new virus is a type called a novel coronavirus. How does a novel coronavirus work?

The novel coronavirus, recently named Middle East Respiratory Symptom Coronavirus, or MERS-CoV, is a member of the coronavirus family; viruses from this group can cause symptoms ranging from the common cold to severe respiratory illness.

There is not yet a definitive understanding of how the virus spreads, but human-to-human transmission has been reported for several clusters, particularly in cases with sustained contact such as health-care workers. SARS, also a coronavirus, was spread through respiratory droplets from coughing or sneezing.

How is this virus different from SARS?

Both SARS and MERS are in the same family of viruses—the coronaviruses—but they differ enough genetically to allow us to conclude that they emerged independently from each other.

Why is this new coronavirus spreading so quickly? What do we know and what don't we know about it?

What we know:

MERS was first recognized in the Middle East in September 2012. As of last week, the WHO had reported a total of 49 infections and 27 deaths in eight countries including Saudi Arabia, Tunisia, Jordan, Qatar, the United Arab Emirates, the United Kingdom, and France. MERS produces severe respiratory symptoms including fever and cough, as well as gastrointestinal symptoms, pneumonia, and kidney failure.

What we don't know:

There is still much to be discovered about MERS. We do not know how MERS originated, and while human-to-human transmission has been confirmed, we do not know the precise mechanism of transmission. We still don't know definitively what percentage of people who are infected will die (i.e., the case mortality rate). While 50 percent of the identified cases have died, it may be that only sicker individuals are being identified. Individuals who have milder symptoms may not come to hospitals and [may] be less likely to be identified—if so, the current 50 percent mortality rate may be an overestimate.

You spend your days tracking new viruses all over the world. How do you know when you've found a new virus?

We regularly collect blood from people and animals throughout the world. Advances in microbial discovery techniques have increased our ability to find new viruses. For example, recently we identified a novel rhabdovirus from three cases of acute hemorrhagic fever in Central Africa. We knew the virus was novel for two reasons: first, because it had a unique genetic signature distinct from all previously identified human viruses, and second, [because] it caused symptoms previously seen only in infections from viruses from other viral families, such as Ebola, Marburg, and yellow fever.

You founded two organizations, and one of their goals is to stop pandemics. How can we stop this from becoming a pandemic?

We've established two organizations—Global Viral and Metabiota—that work in tandem to address the various facets of pandemics and biological threats. Global Viral focuses on exploratory, basic research while Metabiota assists governments and other organizations to mitigate the risks associated with pandemics and other biological threats. Our mission is to identify viruses before they become pandemics. And we do so by working with governments, NGOs, and other organizations to establish surveillance, laboratory, and data systems aimed at tracking viruses in their earliest stages of spread.

Do we need to be worried about our pets?

While there is no particular expectation that pets are or will be involved, it is possible that MERS can infect pets. The SARS coronavirus, which originated in bats, was identified in both cats and dogs.

What's the most important thing you've learned from collecting blood samples?

Over the past ten-plus years, we've collected over 200,000 blood samples from animals and humans. Probably our single biggest lesson learned is that there's a lot more out there than we're aware of!

Are pandemics increasing in frequency?

A variety of factors, including radically increased mobility among humans and animals, has undoubtedly increased the frequency of pandemics. As we move our animals and ourselves around the world and increase the complexity of our food supply chains, we increase the probability that a new virus can spread rapidly.

Does this virus originate from animals? Why is it that most viruses start from an animal, as opposed to a human?

MERS almost certainly jumped to humans from an animal. In this case it appears most likely that it was at least originally from a bat. There is an incredible reservoir of known and unknown viruses in animals around the world—each species has its own microbial repertoire. This pool of microbes is not static—it continues to mutate and mix genes, leading to a large pool of potential agents that can infect us. And while some older human viruses can spread through changing conditions, it's estimated that 75 percent of emerging infectious diseases in people originate from an animal source.

What are health officials doing now? And if this spreads, what will they be doing?

We're living in a remarkable time. While the risks of pandemics have increased dramatically, so too has the global level of scientific and public health expertise. Among the exciting trends that we've seen in both the recent outbreaks of H7N9 and MERS is a high level of international collaboration and transparency. Viruses don't respect borders between countries, and our efforts to combat them must truly be global.

How can we protect ourselves?

Protecting ourselves as a planet requires long-term commitments to closely monitor hot spots—such as where animals and human frequently come into contact—as well as the resources to equip field teams, laboratories, and data scientists with the tools they need to monitor and respond to these events. Programs like the U.S. Agency for International Development's Emerging Pandemic Threats Program, the U.S. Department of Defense's Cooperative Biological Engagement Program and Armed Forces Health Surveillance Center, and a growing number of foundations, such as the Skoll Global Threats Fund and the Wellcome Trust, work around the world with organizations like ours to help improve and fortify these efforts. These programs have already led to a range of successes, but long-term efforts are needed and the work has really only begun.

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