We have an eclectic team here at SciCulture, but none of us are experts in medicine or virology. But we still want to try and answer any questions you may currently have about the coronavirus, so we have outsourced… Meet Paul Hunter, Professor of Health Protection and expert in infectious diseases based at the University of East Anglia (UEA)
Could you introduce yourself, what is your background?
I am Paul Hunter I graduated in Medicine from Manchester University and then specialised in Medical Microbiology and Virology. After training posts in Manchester, Cardiff, and London I was Consultant at the Countess of Chester Hospital until I became Professor at the New Medical School at the University of East Anglia in 2001. My main interests are in emerging infectious diseases with a particular interest in food and waterborne diarrhoeal diseases. I have published work on SARS, Dengue, Avian influenza, cholera Ebola, Zika and now COVID-19. I am a member of the World Health Organisation.
In times of global crisis do we need to learn how to collaborate with other countries and consult experts in a trans-disciplinary fashion? How do you think this would have helped reduce the spread of the virus?
Absolutely, one of the problems with the current outbreak has been the fact that different countries have been doing radically different things. This only leads to confusion and makes it more difficult to control. this is most obvious when you look at how countries like the United States have responded to the threat Compared to countries such as South Korea.
Medical staff, I think, were in South Korea, are wearing 2 layers of personal protective equipment (PPE)….. What do you think medical staff should be wearing to protect themselves?
The issue of PPE has been one of the most contentious areas of debate. we know that the primary means of transmission is by droplets spread this can simply be managed by ordinary surgical masks, eye protection, and gowns. There may be some aerosol transmission, but this is likely to be restricted to certain aerosol-generating procedures such as tracheal intubation, cardiopulmonary resuscitation, and bronchoscopy. In these cases, additional protection such as wearing N95 respirators may be necessary. I do not think that in most circumstances two layers of PPE are necessary. Indeed current evidence is that in most circumstances being extra rigorous with PPE does not provide additional protection.
Is it possible to catch it just walking through the air where an infected person has breathed outdoors? People look at me like I’m mad when I wear a mask…. But many countries advocate masks for all.
It is certainly possible that transmission could occur in this situation, but I think it is not very likely. The wearing of masks in the community is a very contentious issue. My group has reviewed the evidence and it must be said that the quality of evidence is not good enough to make a really informed decision either way. There are two big concerns with wearing face masks in public. The first is that the demand for face masks may then mean that healthcare workers wouldn’t be able to have access to the PPE that they need. the second concern is that people wearing face masks may have a false sense of security and increase behaviors that bring them into contact with others, so spreading the infection. However, some experts consider that face mask used in the community may be a valuable additional control measure possibly by reducing spread from people who are infectious but not yet sufficiently unwell to realise they have the disease. The jury is very much still out. My personal view is that with current evidence I would not advocate for everybody to wear face masks outside of the hospital. But if people who are particularly vulnerable such as the elderly or people with the pre-existing disease have to leave home for essential shopping or to seek medical attention then wearing a face mask may be advisable. Ideally, these people should not leave their homes, but this is not always possible.
I read a paper yesterday that said that a study had found a link between the A blood group and catching coronavirus. It was a small study in Wuhan. What do you think about this?
I have not seen this paper but it would not be the first time that blood groups were associated with increased risk from certain infections. For example, norovirus is less likely to infect people with blood group B or AB.
What’s the gestation period before early signs of Infection become visible?
the incubation period is quite variable. The median incubation period is about 4.5 days. However, it is not unusual for the incubation period to be somewhat longer than this and occasional reports have suggested times longer than 14 days.
Do we have tentative medical solutions presently? What treatments/preventative measures are there currently available to medical professionals
Currently, there are no specific treatments that have been shown to be effective and so treatment is supportive. By this, we mean keeping the body going and the person alive until the bodies defence system starts to win. There are a number of treatments under investigation at the present though whether any of them are ultimately shown to be effective we will have to wait for the results of clinical trials. One therapy that I think is likely to work is using serum from recovered patients. Such serotherapy does have a long history and initial experience with this in COVID-19 does look promising but as far as I am aware that are new randomised controlled trials yet completed.
Why has this virus been so particularly contagious compared to previous outbreaks (Sars, Bird Flu etc)? What would be the impact if the gestation period was longer?
When we first heard about COVID-19 many of us believed it would be like SARS and we would be able to control it. However, there is one big difference. In SARS, patients were generally most infectious at about 10 days after developing symptoms. So when SARS patients were most infectious they were almost always in the hospital. With COVID-19 patients are infectious very soon after becoming ill and maybe even before. It is much more difficult to control an infection that is infectious before people really know that they are unwell. For some other infections, like influenza it may not be that COVID-19 is more infectious it is more than the population has no prior immunity.
Countries are currently trying to tackle the pandemic and flatten the curve. Once that is overcome, how do we ensure that the pandemic doesn’t come back? Vaccines are still a while away and talk of a resurgence in autumn is already making the rounds.
I think if you can answer this question you will be in line for a Nobel Prize. I personally believe that we will get a second wave towards the end of the year. However, I suspect it will not be quite as severe as what we are seeing now. However, during the winter we are likely to be having problems with influenza and many other seasonal infections which will add further to the burden on our health services. If one of the possible drugs currently under review is shown to be effective then this could have a dramatic impact on the risk and severity of COVID-19 if we see more cases later in the year. I think that there is a growing consensus that COVID-19 will be with us for many years. It is however less likely to become more severe over time as immunity levels build in the population either following natural infection or vaccine-derived immunity.
Is there an increased danger of being exposed to the virus more than once? What does viral load mean?
There are suggestions in the media that certain patients have become re-infected after recovery from that first illness. I am not sure I believe these reports and consider them to represent extended infections. Viral load essentially means the amount of virus in the body, usually the concentration in body fluids such as sputum or nasal fluids. If the viral load is high in certain body fluids, then the person may be particularly infectious.
Is cleaning surfaces with a hot steam jet safe or does it cause viruses to become airborne/aerosol? What is the best method for cleaning surfaces to prevent the spread of the virus?
The WHO says “It is important to ensure that environmental cleaning and disinfection procedures are followed consistently and correctly. Thoroughly cleaning environmental surfaces with water and detergent and applying commonly used hospital-level disinfectants (such as sodium hypochlorite) are effective and sufficient procedures.
How important is having a reliable test, why are some countries being hesitant in rolling out wider testing schemes?
Very important. There are two types of tests. A test for the virus usually using a throat or a nose swab. This tells you whether or not you are currently infected. This is essential for the diagnosis of an ill person or early detection of someone who may be infectious. The antibody test tells you whether or not you have had the infection and are, therefore, likely to be immune. The antibody test only becomes positive about 10 to 14 days after the onset of symptoms and so is useless to diagnose an acutely ill person. But it will tell you whether or not you have had the infection and so are immune. This will be helpful for people to be able to work in settings where they may be exposed but not to worry about getting the infection again or be a risk to their families. The virus detection test was developed early in the pandemic. The problem is that the reagents needed are in short supply and those countries that had not expected to have to do a lot of tests found that global demand for reagent had outstripped supply. The antibody test is available but the goal of having one that can be used in people’s homes has not to be realised as some available tests may not have been sensitive enough.
Are we facing an increased risk of these sorts of pandemics more often? Will this become a common occurrence? What can we do to remedy this?
We are. You only have to look back on the past few years. COVID-19, Zikavirus, Ebola, cholera, avian influenza. There are several really important steps that we need to follow. Ban the trade in wild animals as many epidemics have a zoonotic origin in that they come from animal species. Protect environments so those wild animals are not forced into close proximity to humans. Reduce human conflict and work to stop wars. Also, maintain public health infrastructure.
Beyond the urgency of attending to the COVID-19 emergency, are there any unexpected insights about health (whether public health or individual health) that have emerged or become clearer in the current context?
Don’t assume a new epidemic will always be the same as the previous epidemic just because it is a very similar virus. A lot of the problems we are now facing are because we tended to think it would be like SARS or even influenza.
Thank you, Professor Hunter for your time.
Stay safe everyone.