Safeguarding Pigs from Viral Threats: The Fight Against African Swine Fever in Nigeria

WEBVTT

00:00:10.330 --> 00:00:17.829
This is a podcast about one health the idea that the health of humans, animals, plants and the environment that we all share are intrinsically linked.

00:00:18.300 --> 00:00:22.190
Coming to you from the University of Texas Medical Branch in the Galveston National Laboratory.

00:00:22.861 --> 00:00:24.004
This is Infectious Science.

00:00:24.004 --> 00:00:25.844
We're enthusiasm for science.

00:00:26.519 --> 00:00:29.067
This is Infectious Science.

00:00:33.905 --> 00:00:36.771
Welcome to another episode of the Infectious Science podcast.

00:00:36.771 --> 00:00:38.424
This is Dr Matthew Daszho.

00:00:38.840 --> 00:00:49.033
Today we are continuing our conversation with an outstanding group of Nigerian clinicians and scientists that form part of the core of the West African Center for Emerging Infectious Diseases.

00:00:49.033 --> 00:01:02.048
In the last episode we started off by hearing from Dr Scott Weaver, professor and chair of microbiology and immunology at UTMB, about the West African Center, how that program got started and where they hoped to go moving forward.

00:01:02.048 --> 00:01:13.132
Then Dr Nathan Sheahu, a clinician scientist, and Dr Pam Luca, a veterinary scientist, shared their perspectives on emerging infectious diseases, one health and scientific collaboration.

00:01:13.132 --> 00:01:20.969
They also shared some stories about their careers, how they got to be doing the important work that they are doing to make the world a better, more safe place.

00:01:20.969 --> 00:01:45.144
In this part two of the Infectious Science on the Road in Nigeria series, dr Dennis Benta continues the conversation with West African Center for Emerging Infectious Disease colleagues Dr Pam Luca and his colleague Dr Loya Inca Asala, a scientist at the National Veterinary Research Institute, about African swine fever, the livestock production industry and producing vaccines for veterinary use in Nigeria.

00:01:50.480 --> 00:01:54.411
Let's talk about another hemorrhagic fever, but not a zoonotic one.

00:01:54.411 --> 00:01:56.808
Let's talk about hemorrhagic fever in pigs.

00:01:56.808 --> 00:01:58.465
Let's talk about African swine fever.

00:01:58.465 --> 00:02:01.007
Pam, you've worked on African swine fever.

00:02:01.007 --> 00:02:02.403
You're still working on it.

00:02:02.403 --> 00:02:07.533
It's been in the news from China to Central Europe.

00:02:07.533 --> 00:02:11.545
Was recently discovered in Hispaniola, again after 30 years.

00:02:11.545 --> 00:02:13.424
Tell us a little bit about your work.

00:02:13.424 --> 00:02:14.687
The African swine fever.

00:02:15.561 --> 00:02:18.205
African swine fever is actually a viral disease.

00:02:18.205 --> 00:02:29.556
It's not zoonotic but it's a disease of pigs that is caused by the African swine fever virus, because it was first reported in Africa, that was in Kenya in 1921.

00:02:29.556 --> 00:02:32.568
So African swine fever is like about a hundred years now.

00:02:32.568 --> 00:02:48.854
So after that first report it was thought to be an African thing And a lot of work has been done in that part of East Africa to Southern Africa, where it has also infected a lot of pigs, And eventually it moved to Europe, to Spain, Portugal.

00:02:48.854 --> 00:02:52.752
In the 60s It also got to the Caribbean at some point.

00:02:52.752 --> 00:02:58.776
All those ones got eradicated, I think before 2005, when it was reported in Georgia.

00:02:58.776 --> 00:03:03.604
Before then it was only endemic in the island of Sardinia in Italy.

00:03:03.604 --> 00:03:06.473
That was the only place that it was endemic at that time.

00:03:06.473 --> 00:03:39.764
But I think now when it got to Georgia, from Georgia to the Russian Federation and then before it moved to China and then before it came back to center Europe, then moving in and got into the wild boars, The challenge with African Swine fever is that when pigs get infected they actually die from it, Because hardly do you have survivors And when you do, some of them have been described as carriers, whether they shed or they don't shed, But I think the hypothesis is that they shed the virus in the environment.

00:03:39.865 --> 00:03:48.997
So you need to call them And when they come down, what you see is that if it's a subacute case, you just come into the pen and find pigs dead.

00:03:48.997 --> 00:04:00.971
But if it's an acute case, sometimes you come in and maybe you feed the pigs and then much later, when they are supposed to have eaten all the feed, you still find feed in their troughs And sometimes they huddle together.

00:04:00.971 --> 00:04:13.812
There's high fever And you could also have bleeding, and you also bleeding through the nose and things like that, And you could also have subcutaneous hemorrhages on the skin And before you know it, they also die.

00:04:13.812 --> 00:04:21.264
And those ones who will eventually recover, maybe chronic cases, like I said, and they go on to become carriers.

00:04:21.264 --> 00:04:33.153
So you wouldn't want carriers on your farm And because these are animals that are being consumed in high proportion, I think in terms of peak consumption globally, I think peak comes number one at some point.

00:04:33.153 --> 00:04:40.076
So a lot of people consume pork And if it's getting to your farm it's not something you can eliminate easily.

00:04:40.076 --> 00:04:50.935
So nobody wants to have airsave on this farm because of the volume of mortality that you have, And it also doesn't have vaccine and there's also no therapy.

00:04:51.204 --> 00:04:55.797
So the basic thing people do now is we encourage farmers on biosecurity.

00:04:55.797 --> 00:05:07.093
You know, if you have a good biosecurity you're going to keep the virus away from the farm, But if you have a very poor biosecurity, in terms of your practices, your hygiene, you're going to be at risk.

00:05:07.093 --> 00:05:12.336
So that's a disease that actually is not even transmitted by the peak itself.

00:05:12.336 --> 00:05:31.608
Human beings are seen as the major carriers or the major vectors in terms of the transmission of the virus, Although you also have the sylvatic cycle of the virus that has been transmitted by the onyxodoros, but that is a soft tick which has only been reported in East Africa and some part of Southern Africa.

00:05:31.608 --> 00:05:39.182
But for us here in West Africa is basically the domestic cycle, as the peak to peak transmission that we have.

00:05:39.182 --> 00:05:44.242
The vector has not really been established to be responsible for transmission.

00:05:44.829 --> 00:05:47.418
So you have African swine fever in Nigeria.

00:05:47.850 --> 00:05:48.411
Yes, we do.

00:05:48.411 --> 00:05:56.416
It was first reported in 1996 and since then it has been with us And we have terrible cases of African swine fever.

00:05:56.416 --> 00:06:00.817
And I think right now, almost on a yearly basis, we have reports of African swine fever.

00:06:00.817 --> 00:06:04.252
So it's there and that has been having its toll on farmers.

00:06:04.252 --> 00:06:25.023
And so, on a routine basis, what we do is that we receive samples from farmers When there are outbreak cases, samples are collected and sent to the lab for diagnosis and confirmation, which we do so that farmers will be able to be guided in what they do And the health authorities are also informed on what they need to do in terms of control measures.

00:06:25.889 --> 00:06:38.543
So if the soft tick that's known to probably transmit but also maybe also maintain the virus in East Africa and South Africa is not present in Nigeria, where does the virus hide?

00:06:38.543 --> 00:06:46.214
Is it always consistently imported, Or is there some sort of an endemic cycle of African swine fever?

00:06:46.569 --> 00:07:03.761
Yeah, it is endemic And sometimes it's maybe transmitted to formites, like I said, because you find in some places where farmers share a lot of farm implements or where a particular community will have a single boa that will be used to serve the other selves.

00:07:03.761 --> 00:07:11.122
So if that peak is infected, for example, the farm is infected, the virus is in the environment.

00:07:11.122 --> 00:07:14.096
You can easily get it because the virus is a little bit hardy.

00:07:14.096 --> 00:07:18.841
You know it's hardy but it's also liberal in terms of disinfectant.

00:07:18.841 --> 00:07:21.250
But it could also survive in the environment.

00:07:21.250 --> 00:07:29.055
It could survive in your sausages for a very long time at certain degrees, in fact in your minus 80, to survive for years.

00:07:29.055 --> 00:07:36.338
So if you have some of these infected animal products, it could serve in preserving the disease in the environment.

00:07:36.939 --> 00:07:40.875
And again, like I said, it's possible also that we have the tick around.

00:07:40.875 --> 00:07:54.163
But we have been trying to look for the ticks because they are nocturnal, they feed only at night, they don't have eyes, so they only come, feed on the peak and then drop off and hide in cracks and crevices.

00:07:54.163 --> 00:08:04.463
So it's wanting to look for those ticks Because, interestingly, there was a time we checked for antibodies to tick, salivary antigens And some of the ticks had those antibodies.

00:08:04.463 --> 00:08:21.790
So which means those peaks were exposed to tick bites, although not all of them had ASF, some, a few, maybe two, three which suggests that possibly the tick is around, but the role it plays in terms of transmission, that is yet to be established, but we can't rule that out.

00:08:22.892 --> 00:08:23.754
Very interesting.

00:08:23.754 --> 00:08:31.495
So with African swine fever you said there's no treatment, so the animals have to be probably destroyed.

00:08:31.495 --> 00:08:41.081
I assume that in Nigeria you have wild boars are correct And they're probably persistent to or not as susceptible as the domestic pigs.

00:08:41.081 --> 00:08:41.702
is that correct?

00:08:42.529 --> 00:08:43.932
We don't have wild boars.

00:08:43.932 --> 00:08:46.619
The wild boars are usually Europe.

00:08:46.619 --> 00:09:01.732
What we have are what hawks, what hawks, bush pigs And even those ones you know, people in Nigeria hunt a lot, so the population of those ones are not much in terms of, maybe, interaction between, let's say, the wild and human interface.

00:09:01.732 --> 00:09:03.515
It's not so much there.

00:09:03.515 --> 00:09:07.082
What we're thinking is responsible for the transmission.

00:09:07.470 --> 00:09:19.243
Maybe periodic outbreaks is as a result of human activities, but in terms of what hawks, bush pigs, red river hawks is not well established because there's no much contact with those ones.

00:09:19.243 --> 00:09:28.120
Usually you find them deep into the forest, deep into the wildlife reserve parks, so they usually don't have them coming close to human habitation.

00:09:28.120 --> 00:09:33.802
And I think there was a time people went in there to sample those ones and none has been tested positive.

00:09:33.802 --> 00:09:44.654
So we wouldn't want to say that they have a role for say, but what we think is that if from the domestic it gets into the wild, it also supports the Sylvatic circle.

00:09:45.115 --> 00:09:48.263
One last question I had for you, maybe to wrap up that topic.

00:09:48.263 --> 00:09:52.437
Can you tell us about the pig industry in Nigeria?

00:09:52.437 --> 00:10:01.001
What is it compared to cattle, to chickens, and where and what parts of the country are the main producers?

00:10:01.889 --> 00:10:04.212
The pig population is not like the cattle.

00:10:04.212 --> 00:10:11.989
I think we have about seven, eight million pigs in the country in terms of population And it's not evenly distributed really.

00:10:11.989 --> 00:10:24.191
You have more large-scale farmers in the southern part of the country and then up north you have small-scale farmers, those who keep in small numbers five to ten, maybe at most 50.

00:10:24.191 --> 00:10:34.004
And those ones are usually rural farmers who keep them in small numbers because it serves as a source of income When they are in need of money.

00:10:34.004 --> 00:10:37.768
they need to pay school fees, they need to take their children to hospital.

00:10:37.768 --> 00:10:42.032
they sell one, get quick money and then solve one or two problems.

00:10:42.032 --> 00:10:50.530
So the population here is not as high as down south, because in the south you have people keeping up to a thousand, two thousand pigs.

00:10:50.530 --> 00:10:54.350
Yeah, a single individual can have that number of pigs in his farm.

00:10:54.740 --> 00:11:05.009
It's a growing industry and I think a lot of people now have turned to eating pork and we also have a lot of Chinese who are coming in, so Chinese also patronize a lot of the pig industry.

00:11:05.009 --> 00:11:13.727
So it's a growing industry because the pig is considered as a very good bio-converter, because it converts any waste material.

00:11:13.727 --> 00:11:18.051
So people don't really put in much but you get something at the end of the day.

00:11:18.051 --> 00:11:20.326
So I would say it's a growing industry.

00:11:20.326 --> 00:11:23.168
But again up north we have the pig market.

00:11:23.229 --> 00:11:25.326
here The pig markets are in the north.

00:11:25.326 --> 00:11:34.671
We collect pigs from individuals from different locations into the central market and they are being purchased and taken down south where most of the consumers are.

00:11:34.671 --> 00:11:42.544
So at the end of the day, when you have those ones are infected and they're taken to the market and then some of them are sold.

00:11:42.544 --> 00:11:43.528
some are not sold.

00:11:43.528 --> 00:11:47.729
the ones that are not sold are taken back but they already be mixed with infected ones.

00:11:47.729 --> 00:11:56.533
So you take an infection back to your farm and then the ones that are taken down south, if they are being infected or have come in contact with infected pigs, they are also taken.

00:11:56.533 --> 00:12:06.504
So the pig market also serves as a mixing point for healthy and infected, and then healthy ones become infected Or they become carriers.

00:12:06.504 --> 00:12:11.504
so you end up contaminating the environment and other pigs also come down Very interesting.

00:12:11.563 --> 00:12:12.386
Thank you, yeah.

00:12:16.240 --> 00:12:19.048
Don't let the name West Nile Virus trick you.

00:12:19.048 --> 00:12:23.871
Outbreaks of this virus happen all across the United States and even in Texas.

00:12:23.871 --> 00:12:33.149
According to the CDC, there were almost 2,700 cases in the United States and 77 cases in Texas in 2021.

00:12:33.149 --> 00:12:39.231
It's transmitted through mosquitoes, which means wear your insect repellent during the summer fall months.

00:12:39.231 --> 00:12:51.013
One in five people develop symptoms such as fevers, rash and headaches, but some people can develop serious symptoms such as convulsions, vision loss and paralysis.

00:12:51.013 --> 00:12:54.529
Seven Texans died last year to the West Nile Virus.

00:12:54.529 --> 00:13:01.807
There are no vaccines or cures, so prevention is our best solution, and now you know about the West Nile Virus.

00:13:01.807 --> 00:13:03.466
This has been a viral minute.

00:13:06.179 --> 00:13:16.741
So we had the chance today to see the National Veterinary Research Institute and I saw that you're actually producing 20 vaccines locally, dr Asala.

00:13:16.741 --> 00:13:27.809
maybe you can tell us a little bit about what it takes to produce locally, and I'm especially interested in the vaccine acceptance and how do you distribute the vaccines to the end users.

00:13:27.809 --> 00:13:29.524
Is this an easy process?

00:13:29.524 --> 00:13:32.291
I know cost of vaccines is always an issue.

00:13:32.860 --> 00:13:35.788
Yeah, for the National Veterinary Research Institute.

00:13:35.788 --> 00:13:48.409
Looking at our history, we will be 100 years in two years' time and actually how the city came to be was as a result of Rindapest that ravaged some parts of West Africa, the cattle population.

00:13:48.409 --> 00:13:58.244
So then we were under the British colonial rule and through the initiative, we're producing hyperimmune sera in order to tackle the disease.

00:13:58.244 --> 00:14:06.210
And so After Rindapest I think in 2011, nigeria finally declared free of Rindapest, so we're Rindapest free at the moment.

00:14:06.210 --> 00:14:15.214
So the course of the journey, other outbreaks of other diseases of importance came into being, like Newcastle, brucellosis and all that.

00:14:15.214 --> 00:14:21.217
And with that, vaccines were developed with expertise and support from also British government.

00:14:21.217 --> 00:14:25.955
And over the years, as time went on, we kept on improving on what we were doing.

00:14:25.955 --> 00:14:33.570
From using tissue culture we came to sell culture and actually we're still producing using the conventional vaccine technology.

00:14:33.570 --> 00:14:42.955
And with that, vorma's actually, or NVR has actually made a name and we have the only vaccine producing institution or establishment in Nigeria.

00:14:43.885 --> 00:14:49.357
And for the demand, in short, we are able to meet the national demand.

00:14:49.357 --> 00:14:55.157
So government also, or pharmacy, rely on importation of other foreign vaccines to be able to meet the demand.

00:14:55.157 --> 00:15:13.312
So for distribution and acceptance, in short, we're overwhelmed by requests and like we're always at our toes to produce, like I was in the meeting I had to leave three times because one call or the other one vaccine that needed to be dispensed And for us to facilitate distribution around the country.

00:15:13.312 --> 00:15:24.695
We have about 23 outstations, so we have our stations in 23 states out of the 36 where we have staff via which also render both diagnosis, also facilitate distribution.

00:15:24.695 --> 00:15:35.197
So we move vaccines from Vorma to such places and then it can easily be reached by farmers and also the staff and our outfit also render services to farmers, to farms.

00:15:35.197 --> 00:15:48.807
That way our vaccine coverage is national and sometimes we also have requests from sister colleagues like West Africa, for vaccines like against transbound diseases, like CBPP, fmt and that.

00:15:49.706 --> 00:15:58.453
So Dr Luca was talking about the smaller big holders in the north, not so much the big markets or owners in the in the south.

00:15:58.453 --> 00:16:01.133
Do they have the means to afford these vaccines?

00:16:01.133 --> 00:16:06.947
I would imagine they are the lowest cost, but still is this for those smaller producers like doable?

00:16:07.409 --> 00:16:17.792
Yeah, and for us, remember, we national institute, so our boxes are usually subsidized by the government, And then we have a lot of government interventions.

00:16:17.792 --> 00:16:32.736
At the moment, for instance, for the rabies and the rabies vaccine, there's a national campaign and we are to produce about 2 million doses of rabies vaccines and it's distributed free to all the states, and so all what the state government needs to do is just to mobilize strategies for vaccination.

00:16:32.736 --> 00:16:46.331
So every year we have a lot of states coming in to mitigate and give support to farmers by procuring vaccines from us, and the veterinary ministries or outfits will now go out to get those animals vaccinated.

00:16:46.331 --> 00:17:09.269
And even if you look at the cost of our vaccines, they're still relatively cheap and affordable, because compared to other foreign vaccines, maybe it's cheaper and those sizes are usually smaller, so that it can easily be affordable, because we are not really for profit if we look at it, because we have a lot of subversion and also support yearly from government in order to be able to produce these vaccines.

00:17:09.711 --> 00:17:10.874
Okay, thank you very much.

00:17:13.128 --> 00:17:15.455
Thanks for listening to the Infectious Science podcast.

00:17:15.455 --> 00:17:23.473
Be sure to hit subscribe and visit infectiousscienceorg to join the conversation, access the show notes and to sign up for our newsletter and receive our free materials.

00:17:24.065 --> 00:17:32.236
If you enjoyed this new episode of Infectious Science, please leave us a review on Apple Podcasts at Spotify and go ahead and share this episode with some of your friends.

00:17:32.807 --> 00:17:37.349
Also, don't hesitate to ask questions and tell us what topics you'd like us to cover for future episodes.

00:17:37.349 --> 00:17:41.695
To get in touch, drop a line in the comments section or send us a message on social media.

00:17:42.105 --> 00:17:47.692
So we'll see you next time for a new episode, and in the meantime, stay happy stay healthy, stay healthy, stay interested.