Friday, 20 September 2013

Happy 1st birthday Middle East respiratory syndrome coronavirus (MERS-CoV)

A coronavirus schematic. The spiky bits give the virus
its name(corona=crown) and represent the
receptor binding, antigenic Spike protein. 
...I can remember when you were just a novel little thing.
How you have grown young prince and how clever of you to emerge in a Kingdom of all places (corona=crown, named for it's spikey appearance). You've certainly garnered attention worthy of a King given the relatively few cases of disease you gave been associated with in the first year we've known of you.

It was September 20th when Dr Zaki 1st alerted the world to the death of a Saudi man due to what looked to be a new coronavirus (CoV). Today we have over 135 cases 58 deaths (43%).

I've previously covered Zaki's disocvery and the problems posed for the Kingdom of Saudi Arabia (KSA) by the way in which he announced that discovery, apparently without the Ministry of Health's (MOH) foreknowledge. The way in which the sample was exported from the KSA without their prior consent was also problematic for them.
Soon after we heard of it, we had virus-detection assays with which we could seek out new cases. Were they used as they might have been in the days of the SARS-CoV? Nope. And there still seems to be only a single laboratory in KSA testing for MERS-CoV (despite reports of 3), with Dr Abdullah Al-Aeeri (a director of hospital infection control) claiming a 72-hour reporting turnaround time.

Is there an antibody detection assay that has been validated using a panel of known positive sera? Nope. There are some innovative antibody-detection methods around but why do they only include a single positive control? Is there no collaboration at all? Why is the KSA not leading the charge to develop these diagnostics and to hunt for an animal host? Why wait on advice from external organizations to screen samples? Why has the necessary testing capacity not been built well before now? Is it to do with that pesky material transfer agreement? I hope not because there is little evidence for that being a real block to anything from a public health standpoint.

At least we have some new MERS-CoV sequences to celebrate the birthday with. Although they and the 9 preceding them represent less than half of the relatively small number of cases described to date. Why can't the typing region sequences be released? That should really be part of the diagnostic process. Okay, those may not inform us about the evolution of key regions of the virus but they do confirm it is the strain we know. Why not focus on full or subgenomic Spike gene sequences? They might be a better sentinel for keeping tabs on MERS-CoV change over time.

Most of the detail about MERS-CoV and cases of MERS has come through the peer-reviewed scientific literature. That is pretty normal for respiratory viruses that are not notifiable. But it's generally a slow medium. Is MERS infection a notifiable disease? It is in some countries (e.g. the US and New Zealand), but is it at the epicenter of the outbreak, the KSA? I'm not sure. It's not obviously stated as such anywhere I looked on the KSA MOH website.

The World Health Organization politely notes:

WHO encourages all Member States to enhance their surveillance for severe acute respiratory infections (SARI) and to carefully review any unusual patterns of SARI or pneumonia cases. WHO urges Member States to notify or verify to WHO any probable or confirmed case of infection with MERS-CoV.

How's that been working out? In a nice summary of the lack of communication, Helen Branswell and Declan Butler highlight that, as usual, everyone  who was asked agreed that it's not working out well at all. In fact it's pretty woeful. And to add to matters, the latest WHO Disease Outbreak News (DON) takes the form of a summary of 18 "new" cases; no extra or confirmatory detail to be had from it. SO the KSA MOH is now the source for detail.

If we were talking about wanting more data on the monthly proportion of rhinovirus infections, the KSA would be justified in saying that the world doesn't need to know (I'd like to but that's my thing). 

If we were talking about influenza, then there are plenty of international public health sites publishing these notifiable data on the internet; here's Queensland, Australia's for example.

But we're talking about an emerging disease which kills half of the people it infects, is caused by a novel virus for which no host is known, which transmits between people in a way we don't yet understand, which is shed from ill (or well) people for an undefined period of time (if at all), which remains infectious in the environment for who knows how long, which jumps to other countries, which may only cause severe disease in those who are already ill with another disease, which may be endemically spreading within the community as mild or asymptomatic infections, for which there is no vaccine or proven antiviral therapy available..I'd say it's a no-brainer that at the very least the WHO deserves regular and detailed updates of what's going on. Reading between the lines, that does not seem to be happening even behind closed doors.

The mass gathering of pilgrims known as the Hajj is fast approaching. This may trigger a large increase in MERS cases or, in the worst case, a pandemic. I personally believe it won't go that far. We shouldn't forget is the 2nd Hajj for MERS. But perhaps the virus is much more widespread than it was in October 2012. But without testing data, we can only guess.

So, it's your 1st birthday MERS-CoV. But instead of wishing you a happy birthday you opportunistic, spiky little killer, I'm wishing Dr Zaki well and congratulating him on co-parenting the birth of this novel coronavirus. Going by what we've seen to date, his actions may have been the only way we would have ever heard of this virus otherwise.

And, as noted previously, but not given much air to in the above rant (thanks to @MicorbeLover for straightening me out)...

It's very sad that there are real people in these numbers who have died from MERS. You may have noticed that I try and stick with the cold number-crunching aspect of these outbreaks. It's not because I'm a heartless b&^$# but because that is not what this blog is about. That and my editorialisation and expositionary writing consume what little time I have spare. But I don't feel that I have enough information to make any other comments about these or any other lives lost to infectious disease. I personally feel that any unexpected and acute loss of life (if I had to scale loss of life) is the worst kind of loss; it's a waste of potential, a source of great sorrow for all involved and it's something we should all strive to prevent, if we can. I know that's not much to convey, but it's all I can offer from my kinda comfy chair in Brisbane. 

The MOH says it better in anyway; May Allah have mercy upon the deceased.