Credit Wikipedia
# 8614
The news yesterday that a second MERS infected Health Care Worker (HCW) flew into the United States from Saudi Arabia is additional proof (as if we needed it) that airlines are a competent vector of infectious diseases, and that oceans and borders offer little protection against the proliferation of emerging viruses.
The early (prodromal) presentation of MERS can be mild and non-specific enough (typically fever, chills, malaise) to convince most patients – even HCWs who have recently worked in a MERS hot zone – that what they have is nothing more than a `summer cold’.
Add in the fact that these early symptoms don’t present until days after exposure – well, short of placing Samuel L. Jackson on every international flight - there’s not much hope (warning: gratuitous movie reference ahead) in eliminating Shakes on a Plane.
Granted, one would hope that in this age of emerging infectious disease, anyone feeling unwell on an airline flight would request - and be provided with - a surgical facemask. HCWs, particularly those coming from an area where MERS is active, should certainly give extra consideration to the fact that they might be infected.
Hopefully some appropriate signage at airports informing passengers of the symptoms of MERS, and that they should notify the flight crew if they feel unwell, will lead to these sorts of measures.
But the reality is, denialism – combined with an overwhelming desire to `get home’ – may induce some people to wait to see if they feel worse before saying anything that might endanger their itinerary. During the initial outbreak of H1N1, we saw airline passengers taking fever-reducers to beat the airport scanners in order to get home (see Vietnam Discovers Passengers Beating Thermal Scanners).
During yesterday’s CDC press conference, CDC Director Tom Frieden addressed the topic of airport screening for possible MERS cases:
In terms of the border issues, CDC has quarantine stations at all of the major airports of entry in the U.S. If someone has symptoms, we are immediately contacted. If need be, we will go on board the plane. We do not recommend screening of people coming off. We don't find that to be productive. First off, many people who may be ill may not be identified as being ill. And second, many people who will be ill with routine colds and minor conditions would be. So we've looked at that and not found that to be something we would recommend at this time.
A bit of a misnomer, `quarantine stations’ aren’t actually quarantine facilities, but are stations - located at 20 ports of entry and land-border crossings (see map below) - that are staffed by CDC medical and public health officers.
Location of US CDC Quarantine Stations
The CDC Quarantine Station FAQ lists their Mandate:
Authority and Scope
CDC has the legal authority to detain any person who may have an infectious disease that is specified by Executive Order to be quarantinable. If necessary, CDC can deny ill persons with these diseases entry to the United States. CDC also can have them admitted to a hospital or confined to a home for a certain amount of time to prevent the spread of disease.
Daily Activities
Medical and public health officers at U.S. Quarantine Stations perform these activities:
Response
- Respond to reports of illnesses on airplanes, maritime vessels, and at land-border crossings
- Distribute immunobiologics and investigational drugs
- Plan and prepare for emergency response
Quarantinable Diseases by Executive Order
- Cholera
- Diphtheria
- Infectious tuberculosis
- Plague
- Smallpox
- Yellow fever
- Viral hemorrhagic fevers
- SARS
- New types of flu (influenza) that could cause a pandemic
Migration
- Monitor health and collect any medical information of new immigrants, refugees, asylees, and parolees
- Alert local health departments in the areas where refugees and immigrants resettle about any health issues that need follow up
- Provide travelers with essential health information
- Respond to mass migration emergencies
Inspection
- Inspect animals, animal products, and human remains that pose a potential threat to human health
- Screen cargo and hand-carried items for potential vectors of human infectious diseases
Partnerships
- Build partnerships for disease surveillance and control
Although it isn’t what most people want to hear, there is no technological barrier that can effectively keep infected people from traveling internationally. It is the price we pay for having an increasingly mobile, and interconnected, society.
Last month, in MERS: The Limitations Of Airport Screening, we looked at the poor performance of airport screening programs during the H1N1 pandemic, and the scientific consensus that screening programs are unlikely to provide much benefit (see Helen Branswell’s Airport disease screening rarely worthwhile, study suggests).
The good news – at least as far as we know today – is that MERS shows no signs of being anywhere near as contagious as influenza, and that the risks of contracting it through casual contact with an infected person is thought exceedingly low. Family members, care givers, those with close, prolonged contact, and HCWs appear to be most at risk.
Meaning that simply sharing the same air flight, or standing in queue at the air terminal with someone who is infected, is unlikely to present much risk.
The concern is, that over time MERS may gain transmissibility, making it a greater public health threat. If that will happen is unknowable, but each human infection gives the virus another opportunity to `figure us out’.
But whether the next pandemic threat turns out to be due to MERS, one of the many strains of avian or swine flu (or something completely out of left field), our best defense is for emerging viruses be identified and quashed at the source, before they have the opportunity to board a plane and spread globally.
Making investments in global health, research, and human (and animal) surveillance relatively cheap insurance for a world that is increasingly vulnerable to another great pandemic.
Apparently I’m not the only one with MERS and Travel on the brain this morning, as Dr. Ian Mackay has his own offering called:
"Assessment of the MERS-CoV epidemic situation in the Middle East region."
Reprinted with kind permission of author (Dr Vittoria Colizza, pers comm).Click on image to enlarge.
This is perhaps a timely reminder of where cases of MERS-CoV may pop-up if we look at the author's analysis of destinations from major departure airports in the Kingdom of Saudi Arabia, Jordan, Qatar and the United Arab Emirates.
