Middle East Respiratory Syndrome Coronavirus

Middle East respiratory syndrome coronavirus: how tough is it?

Slide tweeted by @HZowawi captured from my talk on H7N9

and MERS-CoV presented at the Royal Children's Hospital, 

Brisbane, Queensland, to the local Serology/Virology & 

Molecular Special Interest Group of the Australian Society 

of Micorbiology. 15th October, 2013.

This publication is nearly a month old so apologies if you know of it already.

For the rest of you, Doremalen , Bushmaker and Munster recently wrote in Eurosurveillance about the results of their experiments to discover how resilient MERS-CoV is on surfaces at different humidities and temperatures and how it survives in an aerosol. They also used MERS-CoV (the EMC/2012 strain) to influenza A (H1N1)pdm09 (Mexico/4108/2009 strain) virus for comparison.

Some key findings below (you can read the entire article yourself because this excellent journal has open access):

Plastic and steel surfaces behaved similarly for these viral survival studies MERS-CoV was still infectious after 48-hours at 20°C in 40% relative humidity (RH; low humidity similar to indoors).  MERS-CoV remained viable for 8-hours at high temperature (30°C)/high humidity (80% RH) and 24-hours at high temperature/low humidity (30% RH) (H1N1)pdm09 was inactivated after 4-hours at any of those conditions Viruses were aerosolised and the amount of viral RNA and viral infectivity compared at 20°C/40%RH or 20°C/70%RH, after

the aerosol was impinged into tissue culture medium. MERS-CoV viability dropped 7% at 40%RH and 89% at 70%RH - both at 20°C. Viral genome copies did not drop significantly. (H1N1)pdm09 dropped 95% and 62% respectively. SARS-CoV reportedly survives for 5-days at 22-25°C and 40-50%RHThe authors go on to conclude that MERS-CoV remains viable in the air and on surfaces for longer than a pandemic influenza virus. When you consider that a pandemic results largely from efficient transmission, of which virus stability is a component, this is a significant study.

These are pure preparations of virus under experimental conditions so it's fair to say that things would be different "in the wild". Rougher environmental conditions may accelerate viral decay although, if larger droplets were expectorated during coughing fits, extra material may act to prolong the survival of virus.

Transmission through fomites (e.g. door handles, glass screen phones, other hard surfaces, cups, utensils, clothing) is a possible route that now has some data to support it-although the current high temperatures (30s-40°C) in the Kingdom of Saudi Arabia suggest survival on surfaces, away from air

conditioning, won't be for long.

What would be nice to know next, is whether mild and moderate cases of MERS are also capable of producing aerosolised virus. And what about asymptomatic cases? What about the mysterious animal sources? Could infected animal excreta further prolong viral survival? So many questions.Posted by Ian M Mackay Email ThisBlogThis!Share to TwitterShare to Facebook   

Why palm tress in the MERS-CoV acquisition model...?

Click to enlarge. See more at earlier post.

I have palm trees drawn in as a sort of focus for my hypothetical acquisition model for the Middle

East respiratory syndrome coronavirus (MERS-CoV). 

I first posted this graphic back in late August. It shows ways in which humans might acquire/have acquired the (probably) occasional MERS-CoV infection from an (suspected) animal host/intermediate host.

You can probably see from that paragraph, that this is just some crazy thoughts and there are no data that link them together.

I was recently asked why the palm trees? My thinking here was that date palms, and perhaps other flowering trees, may attract insectivorous bats as well as providing shade, and perhaps water if nearby, for animals and humans. This could create a point of cross-over between species - even if they don't directly co-mingle there may be opportunity to come in contact with contaminated excreta, saliva or partially eaten fruit or bugs.Posted by Ian M Mackay Email ThisBlogThis!Share to TwitterShare to Facebook   

What is Coronavirus (MERC-CoV)?

Coronaviruses are a family of viruses that can cause colds, and in some cases can cause severe acute respiratory syndrome (SARS). Most cases of the virus infections have common symptoms including high temperatures, body aches, sore throat, running nose and cough. In most circumstances, these symptoms last for days and then disappear. The Ministry of Health (MOH) is working alongside with the World Health Organization (WHO) to discover more about the pathology of the virus.  

HWhy is this virus dangerous? 

There is still limited information about the characteristics and transmission of Coronavirus, the Ministry of Health is coordinating with the World Health Organization (WHO), as well as a number of international experts, to learn more about it. Medical consensus recommends that citizens, residents and visitors observe general health guidelines to contain the spread of all infectious respiratory diseases.   oHow spread out is the virus within the Kingdom of Saudi Arabia? 

Since its emergence, Coronavirus cases have been detected in a number of regions across the Kingdom. The Ministry of Health’s website is being updated on a daily basis with those numbers. It is important to keep things in perspective: the total number of cases of infection in the kingdom from the month of Shawwal 1433H (September 2012) and as of 6 May 2014 are 449 cases, with 121 fatalities. The number of verified cases of infection on May 6, 2014 was 78 active cases.w

does someone get infected with the virus? 

There is an assumption by the medical community that this strain of Coronavirus is transmitted similarly to alternate strains which includes:  

Direct transmission through droplets expelled during coughs and sneezes. Indirect transmission through touching surfaces and devices contaminated with the virus, and

then touching the mouth, nose or eyes. Direct contact with patients or infected animals or animal products.

 The Ministry of Health (MOH) is working closely with a number of international organizations, including the World Health Organization (WHO), to determine how the virus is spread, in humans and animals.   

Is the virus airborne? 

The current medical consensus and evidence suggests that this is not the case.The Ministry of Health (MOH) is working closely with a number of international organizations, including the World Health Organization (WHO), to determine how the virus is spread, in humans and animals.   

ymptoms of Infection with The Middle East Respiratory Syndrome-Coronavirus (MERC-CoV)

According to the discovered cases so far, the symptoms may include the following:

1. Fever and cough.2. Shortness of breath3. Congestion in the nose and throat4. Diarrhea.5. In advanced cases, the patient can have very serious complications, which may lead to death,

such as: severe pneumonia.

Transmission:

According to the limited information available so far, there is no accurate scientific evidence identifying the way through which the virus can be transmitted from one person to another. But, it is likely to be similar to the other kinds of Coronavirus. MOH is making every effort, in collaboration with its partners in the international organizations, including the WHO, to learn more about ways of

transmission, including through animals.

The ways of human-to-human Corona transmission include the following: 

Direct transmission through droplets produced during coughing or sneezing. Indirect transmission through touching surfaces and devices contaminated with

the virus, and then touching the mouth, nose or eyes. Direct contact with infected patients. Put on face-masks only if you are sick or visiting sick patients.

 Ways of protection against the The Middle East Respiratory Syndrome-Coronavirus (MERC-CoV)

The Ministry of Health recommends citizens and residents generally to abide by the following health guidelines to limit the outbreak of flu and infectious respiratory diseases until we know the ways of the virus transmission:

Wash your hands well and continually with water and soap, or with other disinfectants used for hand washing, especially after coughing, sneezing and using toilets. Also, don't forget to wash your hands before and after handling or preparing foods, and when dealing with patients or their personal tools.

Try as much as possible to avoid touching the eyes, nose and mouth with your hand, because it can transmit the virus after touching surfaces contaminated with the virus.

Avoid as much as possible contacting with infected people.

Use handkerchief when coughing or sneezing and cover your mouth and nose with it, then get rid of the handkerchief in a waste basket. If there are no handkerchiefs, it is preferred to cough or sneeze in the top of your arm, not in the hands (palms).

Put on face-masks only if you are sick or visiting sick patients

Adhere to hygiene.

Pay attention to other health habits as the nutritional balance and physical activity, as well as taking enough share of sleep, as it helps to increase the body's immunity.

   How to behave in case of infection with the disease?

Of course, the patient can only be known that he is infected with the disease after diagnosis at health facilities. As there is no specific treatment for this disease so far, but in general, dealing with it ought to be in the same manner as any other infectious respiratory diseases such as flu. The patient, therefore, must abide by the following guidelines:

1- Take antipyretic and painkillers medications.2- Drink a lot of fluids and take enough rest and keep on eating healthy food.

3- Follow the guidelines meant to reduce  transmission of the virus, mainly:-  Use handkerchiefs when sneezing and coughing and get rid of phlegm in a safe manner (in the trash).- Wash your hands regularly, and don’t share others in their personal tools such as towels, cups, spoons, etc.- Reduce going outdoors unless necessary.4- You have to visit the health facility immediately when necessary or if the symptoms of the disease increase.5- Elderly patients, health practitioners, people in contact with camels and people of chronic diseases or diseases affecting the immune system, have to review the health facility when feeling symptoms of the disease.

How to deal with the infected cases?

As previously noted, not much is precisely known about ways of virus transmission from one person to others (human-to-human infection). However, generally speaking, MOH recommends those contacting the infected people to follow the rules of infection control, meant to reduce the outbreak of flu and infectious respiratory diseases, mainly:

Wash your hands well and continually with water and soap, or with other disinfectants used for hand washing, after dealing with the infected patient or using any of his personal tools such as towels, eating tools, … etc.

The infected patients have to use handkerchiefs tissues when sneezing or coughing and safely get rid of them in the trash.

Avoid as much as possible contacting directly with the infected people and wear face-masks in case of  direct contact with them.

Avoid sharing the infected patients their personal tools, such as cups, spoons, towels … etc.

Isolate the infected patient in a single room, if possible.

Elderly people  and patients with chronic diseases are recommended not to visit the infected patients.   

Those directly contacting infected patients have to see a doctor immediately on the incidence of any respiratory symptoms.

SARS

Click image to enlarge.Imaging findings at presentation in Saudi patients with MERS. All images courtesy of Lancet Infectious Diseases.

As with severe acute respiratory syndrome (SARS), MERS infecti