Episode 5 – Avian influenza: a bird’s-eye view

Intro (00:10):

Science on the Menu, a podcast by the European Food Safety Authority.

James (00:20):

Hello, listeners, and thanks very much for joining us today on this latest episode of Science on the Menu EFSA's podcast. My name is James Ramsey, I'm the head of communications at EFSA, and today we're going to be talking about avian influenza. So avian influenza is a topic that's featured prominently in the media in recent days, and to talk us through what the virus is all about, and also the work that we are doing here at EFSA we are joined by one of our animal health experts, Francesca Baldinelli. Francesca, very warm welcome. Before we dive into things, maybe you could just tell us a bit about yourself.

Francesca (00:57):

Thank you very much for inviting me. I'm a vet, graduated in Italy. I'm Italian, and I'm an epidemiologist with a PhD in epidemiology and a postgraduate diploma in Animal Health. Before arriving to EFSA, I did several work in other institutes, and I will say that my main work was at the National Institute in Italy for public health, where I've been working for years on zoonotic diseases, so diseases that can be transmitted from animals to humans and vice versa. And then in the National Epidemiology Centre in Italy, still working again on zoonotic diseases. Then I arrived to EFSA and I thought I was working only on animal diseases, but of course, we are in a bigger framework, the one of One Health, so when we talk about human, about animal health issues, they can also develop as human health issues.

James (01:57):

Yeah. Okay. And maybe we come onto that in a bit. That's the concept of kind of One Health and, I presume, I mean, we are not working in isolation. We work with other EU agencies on these kinds of things.

Francesca (02:09):

Exactly.

James (02:10):

Yes. Okay. I presume you also have some experience working in the field as well.

Francesca (02:14):

Yes, I have it, not really as a normal vet, let's say, or what you can expect from a vet, because I've never been doing clinics or surgery, but I've been doing epidemiological work in the field working with, rodents, feral cats in islands isolated. But I should admit that, I mean, really ahead of thinking about the possibility of working i EFSA and with avian flu, I also had field experience with avian influenza.

James (02:46):

Okay. And in what sense?

Francesca (02:48):

Yeah. That’s because my husband is an ornithologist <laugh>. And I've been supporting him years ago, we are talking about 2007 and 2006, supporting him taking samples, swabs, ringing wild birds to be there later analyzed by the EURL for Avian flu.

James (03:12):

Let's talk a bit then about what avian influenza actually is. Can you just explain in kind of broad terms, you know, what the virus is about? Where it comes from, you know, how long we've been living with it, these kinds of things.

Francesca (03:28):

Yes. So first of all, avian influenza is a virus. I think we are all more familiar after the covid time with what a virus is. And the avian flu virus is really similar to the covid in the sense that it is a so-called RNA virus. So it's a virus that when multiplicated inside an host can mutate with a certain level of frequency, like the covid, when they are RNA, it is inside their behavior to mutate.

James (03:58):

So when we talk about avian flu, we are not necessarily talking about the same thing that we are seeing mentioned in the media today.

Francesca (04:05):

It's a huge universe. So we have one type of virus that can have different subtype according to the different protein, that can change. And then we have different strains. So it's really a very huge universe. And the virus evolves. And, we are seeing now viruses that emerged only two years ago or few years ago. And, of course what we see is always just a part of what is outside, because it's really depend on what we are monitoring and the type of surveillance we are doing to really monitor the evolution of the viruses.

James (04:47):

But I presume, hopefully, it goes without saying that, you know, the systems we have in place for monitoring and surveillance now are obviously much improved and continue to improve on a day-to-day basis almost, when it comes to the emergence of new viruses and these kinds of things. And EFSA has a role here as well.

Francesca (05:06):

Yes, yes. We have I will say a very good system to monitoring in the European Union the evolution of avian influenza viruses. It's a continuous collaboration among different institution in the Union. So EFSA, for the animal health side. Then we have the ECDC, from the human side.

James (05:25):

Yeah, this is the European Centre for Disease Prevention and Control.

Francesca (05:28):

Right, James. Yes. And then we also have the great collaboration from the Union Reference Laboratories for avian influenza located in Italy, which is analyzing the genetics of the viruses.

James (05:41):

So as I mentioned before, now that there's a lot of kind of public interest, media interest in this topic, and you could say, increased concern. But why do you think this has happened recently? What is it about avian influenza now, which makes us a bit more alert and, why are we talking about this now?

Francesca (06:04):

Since 2020, October 2020, we are observing and facing the biggest epidemic ever in Europe. So that's clear. That's indicated by the data we had in the last epidemiological here, more than 6,000 cases in birds, which is really very high number of detection of avian flu. We are talking about highly pathogenic avian influenza virus in birds. And this is raising concerns about the persistence of those viruses in Europe. So let me give you some background in relation to the expected expectation avian influenza, because it is considered a seasonal disease. So it appears in Europe in birds with the migratory birds coming from outside the union into the union to winter here. And they can bring the virus along their migration roads. Then during the winter, it is expected that the virus is transmitted between wild birds, but also from wild birds to the poultry. So the domestic birds we raise in the industry. And, when there is the migration back of those wild birds, mainly water birds from the union or from Europe toward outside in Asia for the breeding season, it usually disappears. It means that during the summer there are only few cases of avian flu detected and expected, or no cases at all, as it was in the past years. Whereas after October 2020, we have seen a continuous detection of cases also during the summer, something completely unexpected and new. And what is even newer is the fact that the virus was detected in wild bird species, which were never, very rarely, affected before.

James (08:00):

So these things combined, I guess starts to raise a little bit the attention of scientists, those working in public health, animal health, that something slightly different and unusual is going on here. So no longer can be considered seasonal in the same way that it was before. We see it present in new bird species. Okay.

Francesca (08:23):

Yes, and there are also other signs of unusual presence of the viruses because this very high environmental contamination led to the continuous detection of cases also into poultry, and also to the detection of the viruses is mammals.

James (08:41):

Okay.

Francesca (08:42):

Which are susceptible to highly pathogenic avian flu because this is, let's say a poultry or a birds disease, but it can be also transmitted to humans, and to mammals. And this is what we have been observing since November, let's say 2020. And the number of mammal cases, also, these species are a little bit increasing and also, let's say worrying a little bit because we cannot really predict what will happen in the future, but we know that these are very high environmental contamination concerns all of us.

James (09:17):

In fact, I read, I mean, it's been found in maybe in mammal species that you wouldn't expect at all. Like, I don't know, sea lions.

Francesca (09:26):

Yeah. So that's a very unusual situation that was found in Peru and Chile in the past weeks. And, I mean, when you find a mammal infected, it's because most probably it had eaten an infected bird. So, it is an isolate case, let's say, of a predator of a scavenging that has eaten a burst with the virus. But in this case, there were more than 600 sea lions dead. And, from the analysis, it is proven that it was the avian flu virus causing the death of those animals.

James (10:06):

So that would suggest that there's a kind of sea lion to sea lion transmission.

Francesca (10:10):

This is hypothesis, that cannot be proven, of course. But it is also very unusual to find in that case, 100 carcasses of sea lions floating altogether in one spot.

James (10:27):

Yeah.

Francesca (10:27):

It suggests between mammals transmission or acquisition of the virus from the environment.

James (10:35):

Okay, when the virus is present in bird populations, I mean, that's obviously a big issue. So what do we know about the risks to human health at the moment from this?

Francesca (10:49):

Yes. Of course, human to human transmission has not been observed up to now for this virus. And what I can say is that we work closely with ECDC and the EURL. And according to ECDC, the risk of transmission to humans, to the general population let's say, is still low, whereas the risk of transmission to occupational exposed people, so people working with birds in the farm, because of culling activities or other activities, is considered ranging from low to moderate. But there is really a high uncertainty related to the fact that the virus is continuously mutating.

James (11:30):

So important there to say, when we talk about human cases, we are talking there about humans who have got the virus directly from animals. We're not talking about humans passing the virus among themselves.

Francesca (11:43):

Exactly.

James (11:43):

There we say, still the risk, so animal to human transmission we say the risk is low for the general population, maybe increased a bit for people working who are exposed occupationally to working with birds. What are we doing either at EFSA or, among the scientists who are working on this at an EU level to prepare to get ready in case we arrive at this unfortunate situation where we have human to human transmission.

Francesca (12:14):

Yeah. That's a very interesting point. And this goes behind EFSA’s scope, but our ECDC colleagues are working on this, so they are preparing for this in the really unfortunate event of this will become true. But up to now, there have been no human to human transmission.

James (12:35):

So you mentioned that the risk of the general population is low. Iis there any risk to humans though exposure via food?

Francesca (12:44):

EFSA has estimated the risk of transmission by eating the poultry as negligible. So we should consider that poultry in Europe are under surveillance. They are tested in case of any signs. And, highly pathogenic avian influenza in poultry is a very severe disease. So when it's there, most of the time you can see it, you detect it, and of course, those animals are not designated to the human consumption. We reinforce this message. So negligible risk of acquiring avian influenza virus by eating chicken, let's say.

James (13:21):

Okay. That's good to know. Just, just a bit more on what EFSA is doing. So, we have these quarterly reports that we produce on request of the European Commission, and that provides a kind of update on the status of the epidemiology, how the virus is developing, if you like, what we observe of the virus in the EU and, maybe outside as well. So, what did we find there?

Francesca (13:48):

Yeah, yeah. We have this mandate received from the Commission to give every three months an update of the situation. And this will serve the Commission, the Member States for taking any decision on how to face or control what is going on. And we received recently a request to give a more frequent update starting from now, and also to issue a new report not foreseen. So the main changes are that since December up to beginning of March, we are observing unexpected number of cases in one specific wild bird categories, in gulls.

James (14:28):

Okay.

Francesca (14:28):

So gulls were never, I mean, not never, but very rarely affected before December, and now most of the cases in the wild birds are concentrated in this bird category.

James (14:41):

Okay. Does that raise a specific concern or it's just an observation that we make, that avian influenza can be found in new bird species.

Francesca (14:52):

It's an observation. It happened in the past that new wild bird species were maintaining and spreading around the virus, now it's the turn of the gulls. And of course, then we need to consider the ecology of these species because they are, let's call them, urban species. They are frequently within the city in contact with us, so we will need to consider a different kind of exposure. And according to where they will migrate from now onward, they might bring with them the viruses.

James (15:28):

Okay. So we are working with the ECDC, European Centre for Disease Prevention and Control, on these regular reports. And this gives an overview of the situation, as you said, as far as avian influenza is concerned, do we produce recommendations as well?

Francesca (15:44):

Sure. We produce recommendation every three months, and from different perspectives. Let's say that the main, for example, in relation to the poultry are of course to increase the surveillance in poultry to early detect any cases, and to react immediately to stop the epidemic, to stop the spread. Then if I think about possible cases in wild birds for the general the population, the main recommendation is of course not to touch any dead or sick wild bird you could find. This has to be done if you are well protected with personal protective equipment.

James (16:26):

What about the situation with vaccinations? There was an announcement recently the European Commission announced the rules to harmonise the use of vaccines in the Member States. Are we involved at all in any work on vaccines?

Francesca (16:44):

Yes. We are involved in it and the Commission harmonised the rules across the Member States, according to the international rules for vaccinating against highly pathogenic avian influenza, so following the WOAH standard, which is the World Animal Health Organisation. At the same time, the Commission has also mandated EFSA to assess possible vaccination strategies in poultry and possible surveillance strategies in vaccinated poultry in the Union. And we are working on it.

James (17:19):

Okay. And when's that due?

Francesca (17:22):

After summer, the first part about vaccination strategies and available vaccines that could be used against avian flu and next year March, we will deliver a second part of this work, focusing mainly on surveillance.

James (17:39):

Good. Well, Francesca, thank you very much. I think you've given us really a very comprehensive view, but explain very clearly about the avian influenza, the work we're doing, what it means for Europe and, what we should be looking out for in the future as far as EFSA's work is concerned, and the work of our partner agencies in European Centre for Disease Prevention and Control. And, maybe we can get you back on the podcast in the future at some point to update us again in case the situation changes.

Francesca (18:14):

Sure. Thank you very much.

James (18:21):

That's it for today, listeners, thanks very much for joining us on this episode of Science on the Menu. If you're enjoying the podcast, please do subscribe. And if you want more information on the topic of avian influenza, I would recommend checking out the podcast of our sister agency, the European Centre for Disease Prevention and Control. Thank you very much, and look forward to seeing you on the next episode.