WEBVTT 00:00:00.000 --> 00:00:02.946 align:middle line:90% [MUSIC PLAYING] 00:00:02.946 --> 00:00:07.250 align:middle line:90% 00:00:07.250 --> 00:00:09.000 align:middle line:84% OLAKUNLE ALONGE: Let's spend some time now 00:00:09.000 --> 00:00:11.400 align:middle line:90% and talk about the vaccine. 00:00:11.400 --> 00:00:16.320 align:middle line:84% Again, you cannot have an eradication goal without having 00:00:16.320 --> 00:00:19.860 align:middle line:84% an effective or efficacious intervention, in this case, 00:00:19.860 --> 00:00:21.100 align:middle line:90% a vaccine. 00:00:21.100 --> 00:00:24.560 align:middle line:84% So let's talk about the vaccine and polio. 00:00:24.560 --> 00:00:28.910 align:middle line:84% So earlier, like we discussed, polio was an epidemic disease. 00:00:28.910 --> 00:00:32.990 align:middle line:84% So it was occurring in the US at specific months, 00:00:32.990 --> 00:00:36.050 align:middle line:84% usually the summer months when children, I mean, 00:00:36.050 --> 00:00:38.060 align:middle line:84% are more exposed to the environment. 00:00:38.060 --> 00:00:41.675 align:middle line:84% And then you have the scenario where it will come up 00:00:41.675 --> 00:00:43.370 align:middle line:90% at specific seasons. 00:00:43.370 --> 00:00:45.230 align:middle line:84% And you will have children come down 00:00:45.230 --> 00:00:48.370 align:middle line:84% with the disease and some coming down with paralysis. 00:00:48.370 --> 00:00:50.990 align:middle line:84% And there was a lot of attention to this 00:00:50.990 --> 00:00:53.480 align:middle line:84% because it was really scary, and people really 00:00:53.480 --> 00:00:55.040 align:middle line:90% didn't understand the disease. 00:00:55.040 --> 00:00:59.930 align:middle line:84% And there was not an interest in developing a measure, a vaccine 00:00:59.930 --> 00:01:03.130 align:middle line:90% to address this disease. 00:01:03.130 --> 00:01:06.500 align:middle line:84% So there are two major types of vaccine that were developed, 00:01:06.500 --> 00:01:11.860 align:middle line:84% the Salk vaccine, which was developed in the late 1940s, 00:01:11.860 --> 00:01:16.060 align:middle line:84% slash early 1950s, which is really using 00:01:16.060 --> 00:01:19.440 align:middle line:90% a killed version of the virus. 00:01:19.440 --> 00:01:24.220 align:middle line:84% That is to say, a version that cannot cause any infection 00:01:24.220 --> 00:01:29.660 align:middle line:84% to [INAUDIBLE] development of antibodies within the host 00:01:29.660 --> 00:01:32.810 align:middle line:84% to prevent infection with [INAUDIBLE] polio virus. 00:01:32.810 --> 00:01:35.195 align:middle line:84% So that was really the first vaccine for polio that 00:01:35.195 --> 00:01:37.510 align:middle line:90% was developed by Jonas Salk. 00:01:37.510 --> 00:01:40.690 align:middle line:84% And this is delivered using an injection, a needle. 00:01:40.690 --> 00:01:46.010 align:middle line:84% And then much later on in 1963, an oral version of the vaccine 00:01:46.010 --> 00:01:46.950 align:middle line:90% was developed. 00:01:46.950 --> 00:01:51.080 align:middle line:84% Unlike the Salk vaccine, the oral version of the vaccine 00:01:51.080 --> 00:01:55.400 align:middle line:84% really contained the live virus, one attenuated. 00:01:55.400 --> 00:01:59.120 align:middle line:84% That is to say, that some part of the virus 00:01:59.120 --> 00:02:01.690 align:middle line:84% has been knocked off in the way that it suits-- 00:02:01.690 --> 00:02:02.850 align:middle line:90% it's no longer virulent. 00:02:02.850 --> 00:02:06.170 align:middle line:84% So some particular basis within the virus 00:02:06.170 --> 00:02:08.419 align:middle line:84% has been changed so that it doesn't 00:02:08.419 --> 00:02:13.430 align:middle line:84% cause any virulent infection when it is administered. 00:02:13.430 --> 00:02:16.010 align:middle line:84% But at the same time, it still retains the ability 00:02:16.010 --> 00:02:19.040 align:middle line:84% to [INAUDIBLE] production of immune properties 00:02:19.040 --> 00:02:21.600 align:middle line:84% and antibodies to fight infection. 00:02:21.600 --> 00:02:23.790 align:middle line:84% So that was the oral polio virus. 00:02:23.790 --> 00:02:26.600 align:middle line:90% So we have these two vaccines-- 00:02:26.600 --> 00:02:28.880 align:middle line:84% one, the injectable vaccine, which 00:02:28.880 --> 00:02:33.830 align:middle line:84% is based on the killed virus, and then the oral polio virus, 00:02:33.830 --> 00:02:37.010 align:middle line:84% which is a live virus, but it's attenuated. 00:02:37.010 --> 00:02:40.160 align:middle line:84% It will start to have very reduced ability 00:02:40.160 --> 00:02:43.730 align:middle line:84% to harm the recipient of the vaccine. 00:02:43.730 --> 00:02:48.170 align:middle line:84% In the picture, you see, and still talking about the Sabin 00:02:48.170 --> 00:02:52.820 align:middle line:84% virus, you will see the famous Red Sox team, 00:02:52.820 --> 00:02:57.500 align:middle line:84% really illustrating the usefulness of the oral polio 00:02:57.500 --> 00:02:59.940 align:middle line:90% vaccine or polio prevention. 00:02:59.940 --> 00:03:05.070 align:middle line:84% So this is really helpful for communication and for educating 00:03:05.070 --> 00:03:08.570 align:middle line:84% a population about the safety of the vaccine, 00:03:08.570 --> 00:03:12.422 align:middle line:84% the need for individuals to receive the vaccine, and so on. 00:03:12.422 --> 00:03:13.880 align:middle line:84% And then in the second picture, you 00:03:13.880 --> 00:03:17.140 align:middle line:84% see people lining up to receive vaccination. 00:03:17.140 --> 00:03:18.930 align:middle line:84% I mean, such a lot of the interest 00:03:18.930 --> 00:03:22.400 align:middle line:84% and the desire within the population 00:03:22.400 --> 00:03:23.450 align:middle line:90% to receive this vaccine. 00:03:23.450 --> 00:03:25.220 align:middle line:84% So again, it really described how 00:03:25.220 --> 00:03:29.450 align:middle line:84% it was important in the early '60s to address 00:03:29.450 --> 00:03:34.065 align:middle line:84% polio and people recognized that the vaccine, particularly 00:03:34.065 --> 00:03:35.580 align:middle line:90% the oral polio vaccine. 00:03:35.580 --> 00:03:38.420 align:middle line:84% So this was readily available, it doesn't require 00:03:38.420 --> 00:03:42.680 align:middle line:84% an injection, was a major vehicle for achieving 00:03:42.680 --> 00:03:47.840 align:middle line:84% mass immunization and reducing the epidemic of polio virus 00:03:47.840 --> 00:03:50.590 align:middle line:90% in the United States. 00:03:50.590 --> 00:03:53.110 align:middle line:84% Now, a disease is epidemic proportional. 00:03:53.110 --> 00:03:56.230 align:middle line:84% That is to say, that it occurs at a particular period 00:03:56.230 --> 00:03:57.480 align:middle line:90% and [INAUDIBLE]. 00:03:57.480 --> 00:04:01.240 align:middle line:84% The incident rate is noticeable over that period. 00:04:01.240 --> 00:04:03.300 align:middle line:84% It's easier to communicate effectiveness 00:04:03.300 --> 00:04:05.470 align:middle line:84% with a population of the need to use vaccines. 00:04:05.470 --> 00:04:09.500 align:middle line:84% So everybody can see the disease spreading rapidly 00:04:09.500 --> 00:04:11.620 align:middle line:90% over a period of time. 00:04:11.620 --> 00:04:14.440 align:middle line:84% You see an increased number of cases, 00:04:14.440 --> 00:04:17.420 align:middle line:84% rapid increase in the number of cases over a period of time. 00:04:17.420 --> 00:04:20.200 align:middle line:84% So these are all characteristics of an epidemic disease, which 00:04:20.200 --> 00:04:23.770 align:middle line:84% was the way the poliomyelitis was viewed back 00:04:23.770 --> 00:04:29.470 align:middle line:84% in the early '60s and in the '50s, when 00:04:29.470 --> 00:04:33.590 align:middle line:84% there was a lot of interest in using the vaccine. 00:04:33.590 --> 00:04:36.970 align:middle line:84% That outlook or that perspective is different from the endemic 00:04:36.970 --> 00:04:40.810 align:middle line:84% perspective, in a scenario where the disease is almost naturally 00:04:40.810 --> 00:04:43.620 align:middle line:84% occurring in the population, and you really don't-- 00:04:43.620 --> 00:04:46.643 align:middle line:84% the characteristics is continually transmitting 00:04:46.643 --> 00:04:47.560 align:middle line:90% within the population. 00:04:47.560 --> 00:04:51.450 align:middle line:84% It doesn't have like a specific season or a specific time when 00:04:51.450 --> 00:04:53.240 align:middle line:90% the disease transmits. 00:04:53.240 --> 00:04:55.570 align:middle line:90% So this has implication. 00:04:55.570 --> 00:05:00.010 align:middle line:84% So communicating about the need for vaccine for an epidemic 00:05:00.010 --> 00:05:04.720 align:middle line:84% disease is different of the way that you communicate the need 00:05:04.720 --> 00:05:07.040 align:middle line:84% for vaccines for an endemic disease. 00:05:07.040 --> 00:05:08.560 align:middle line:84% So we know that the epidemic nature 00:05:08.560 --> 00:05:10.930 align:middle line:84% of the polio in the United States in the '50s 00:05:10.930 --> 00:05:13.400 align:middle line:84% meant that it was a source of fear and dread for mothers. 00:05:13.400 --> 00:05:17.210 align:middle line:84% So it was easier to communicate the use of the vaccine, 00:05:17.210 --> 00:05:19.930 align:middle line:84% either the injectable vaccine or the oral polio 00:05:19.930 --> 00:05:21.970 align:middle line:90% vaccine within that scenario. 00:05:21.970 --> 00:05:24.490 align:middle line:84% But in most places where the Global Polio Eradication 00:05:24.490 --> 00:05:27.760 align:middle line:84% Initiative was working, mostly in low-income setting, 00:05:27.760 --> 00:05:29.270 align:middle line:90% the disease is endemic. 00:05:29.270 --> 00:05:32.020 align:middle line:84% That is to say, that it's occurring throughout the year. 00:05:32.020 --> 00:05:34.200 align:middle line:90% There is no pattern. 00:05:34.200 --> 00:05:35.850 align:middle line:84% I mean, there's no epidemic pattern 00:05:35.850 --> 00:05:38.590 align:middle line:84% in which it's classed as around a particular period. 00:05:38.590 --> 00:05:41.020 align:middle line:84% And these are simplification because the way 00:05:41.020 --> 00:05:43.540 align:middle line:84% to communicate the need for the vaccine 00:05:43.540 --> 00:05:46.510 align:middle line:84% is really peculiar, such that because there's a lot of need 00:05:46.510 --> 00:05:48.900 align:middle line:90% to do it on a continuous basis. 00:05:48.900 --> 00:05:52.520 align:middle line:84% There's a lot of need to repeat vaccination and so on. 00:05:52.520 --> 00:05:54.130 align:middle line:84% And therefore, there are strategies 00:05:54.130 --> 00:05:55.960 align:middle line:84% that the Global Polio Eradication had 00:05:55.960 --> 00:05:59.000 align:middle line:84% had to develop or evolve over time 00:05:59.000 --> 00:06:02.830 align:middle line:84% in order to overcome these challenges of maintaining 00:06:02.830 --> 00:06:07.060 align:middle line:84% interest in the vaccination at a global level 00:06:07.060 --> 00:06:09.400 align:middle line:84% and at the country level, and we think of a nation 00:06:09.400 --> 00:06:13.420 align:middle line:84% where the diseases are endemic over a protracted period 00:06:13.420 --> 00:06:14.672 align:middle line:90% of time. 00:06:14.672 --> 00:06:16.380 align:middle line:84% So I would just like you to take a moment 00:06:16.380 --> 00:06:18.010 align:middle line:84% and think again about what are some 00:06:18.010 --> 00:06:21.370 align:middle line:84% of the implications for polio communications 00:06:21.370 --> 00:06:24.340 align:middle line:84% and immunization, where you are thinking about a disease that 00:06:24.340 --> 00:06:24.970 align:middle line:90% is endemic. 00:06:24.970 --> 00:06:26.680 align:middle line:84% That is to say, a disease that is 00:06:26.680 --> 00:06:30.480 align:middle line:84% year-round within a community versus a disease that 00:06:30.480 --> 00:06:33.400 align:middle line:84% is epidemic that occurs at a time-limited period, where 00:06:33.400 --> 00:06:35.890 align:middle line:84% you have your rapid increase in number of cases. 00:06:35.890 --> 00:06:39.730 align:middle line:84% What are the implications of polio presenting or manifesting 00:06:39.730 --> 00:06:41.745 align:middle line:84% as an epidemic disease in a setting 00:06:41.745 --> 00:06:45.790 align:middle line:84% and manifesting as an endemic disease in another setting? 00:06:45.790 --> 00:06:48.150 align:middle line:84% So what are the implications for how you communicate 00:06:48.150 --> 00:06:49.690 align:middle line:84% this strategy, how you communicate 00:06:49.690 --> 00:06:51.760 align:middle line:84% the vaccine, the need for the vaccine, 00:06:51.760 --> 00:06:54.970 align:middle line:84% and how you do mass immunization within each of the settings? 00:06:54.970 --> 00:06:57.400 align:middle line:84% So just take a moment and reflect on this 00:06:57.400 --> 00:07:01.240 align:middle line:84% and discuss with small groups, if you have a small group that 00:07:01.240 --> 00:07:03.520 align:middle line:90% is listening with you, discuss. 00:07:03.520 --> 00:07:06.997 align:middle line:90% 00:07:06.997 --> 00:07:09.410 align:middle line:84% And then, here, I would like you to also go, 00:07:09.410 --> 00:07:11.940 align:middle line:84% pause this presentation at this point, 00:07:11.940 --> 00:07:15.960 align:middle line:84% and then, go and watch the story about the polio vaccines. 00:07:15.960 --> 00:07:19.590 align:middle line:84% And let's think about what are the different advantages, 00:07:19.590 --> 00:07:22.900 align:middle line:84% the disadvantages of the injectable vaccine, 00:07:22.900 --> 00:07:26.070 align:middle line:84% which was first discovered and the oral polio vaccine, which 00:07:26.070 --> 00:07:30.280 align:middle line:84% was later discovered, with respect to addressing academics 00:07:30.280 --> 00:07:34.050 align:middle line:84% of polio, addressing endemic transmission, 00:07:34.050 --> 00:07:36.900 align:middle line:84% and some of the challenges with the properties of the vaccines, 00:07:36.900 --> 00:07:38.490 align:middle line:90% and so on. 00:07:38.490 --> 00:07:43.220 align:middle line:84% So take a pause now and go watch the video. 00:07:43.220 --> 00:07:46.530 align:middle line:84% So what are the advantages of having the oral polio 00:07:46.530 --> 00:07:50.020 align:middle line:84% vaccine, the OPV, which we describe 11 00:07:50.020 --> 00:07:54.140 align:middle line:84% as having a live, but attenuated, version 00:07:54.140 --> 00:07:55.000 align:middle line:90% of the vaccine. 00:07:55.000 --> 00:07:58.780 align:middle line:84% So one big advantage is that it's really inexpensive. 00:07:58.780 --> 00:08:01.370 align:middle line:90% It's less than $0.20 for a dose. 00:08:01.370 --> 00:08:04.610 align:middle line:84% And it doesn't require any trained staff to administer. 00:08:04.610 --> 00:08:06.770 align:middle line:90% And anybody can administer it. 00:08:06.770 --> 00:08:08.800 align:middle line:84% It's just to put a drop in the mouth. 00:08:08.800 --> 00:08:10.510 align:middle line:90% And that's it. 00:08:10.510 --> 00:08:13.230 align:middle line:84% And again, because it's excreted into the environment-- 00:08:13.230 --> 00:08:18.150 align:middle line:84% so remember when we talked about the way poliovirus replicates 00:08:18.150 --> 00:08:19.410 align:middle line:90% in the human body? 00:08:19.410 --> 00:08:23.120 align:middle line:84% It's merely shed from the gastrointestinal tract 00:08:23.120 --> 00:08:25.070 align:middle line:84% and it's excreted into the environment. 00:08:25.070 --> 00:08:27.800 align:middle line:84% And then, as it's circulating in the environment, 00:08:27.800 --> 00:08:29.870 align:middle line:84% people who were not even vaccinated 00:08:29.870 --> 00:08:34.250 align:middle line:84% are exposed to this circulating virus. 00:08:34.250 --> 00:08:37.030 align:middle line:84% And they actually and it literally 00:08:37.030 --> 00:08:40.554 align:middle line:84% seeds a generation of immune properties in those 00:08:40.554 --> 00:08:41.929 align:middle line:84% aren't immunized in the villlage, 00:08:41.929 --> 00:08:44.540 align:middle line:84% So that they're able to develop antibodies 00:08:44.540 --> 00:08:47.180 align:middle line:84% to the wild poliovirus, as a result of exposure 00:08:47.180 --> 00:08:50.510 align:middle line:84% to excretion of the alive attenuated virus that 00:08:50.510 --> 00:08:53.900 align:middle line:84% was excreted by individuals that were immunized. 00:08:53.900 --> 00:08:57.110 align:middle line:84% So this confers what we'll call a "herd immunity." 00:08:57.110 --> 00:08:59.200 align:middle line:84% So you have the benefit of the vaccination 00:08:59.200 --> 00:09:03.800 align:middle line:84% that extend beyond the people that were directly immunized. 00:09:03.800 --> 00:09:06.490 align:middle line:84% Some you have other people that were secondarily 00:09:06.490 --> 00:09:12.770 align:middle line:84% immunized as a result of exposure to the virus shedding 00:09:12.770 --> 00:09:17.025 align:middle line:84% or the vaccine shedding from the individuals 00:09:17.025 --> 00:09:17.900 align:middle line:90% that we're immunized. 00:09:17.900 --> 00:09:20.140 align:middle line:84% So these are some of the relative advantages. 00:09:20.140 --> 00:09:22.490 align:middle line:84% And what these advantages translate to 00:09:22.490 --> 00:09:27.090 align:middle line:84% is that it actually allows for massive, rapid deployment. 00:09:27.090 --> 00:09:28.780 align:middle line:84% So if have your normally trained health 00:09:28.780 --> 00:09:31.220 align:middle line:84% workers to give everybody the vaccine, 00:09:31.220 --> 00:09:34.820 align:middle line:84% you can readily immunize large population 00:09:34.820 --> 00:09:36.420 align:middle line:90% with the oral poliovirus. 00:09:36.420 --> 00:09:38.150 align:middle line:84% You can go door to door, house to house. 00:09:38.150 --> 00:09:40.070 align:middle line:84% You don't need any special technique. 00:09:40.070 --> 00:09:43.390 align:middle line:84% And you can achieve a herd immunity quickly 00:09:43.390 --> 00:09:44.470 align:middle line:90% with the poliovirus. 00:09:44.470 --> 00:09:48.500 align:middle line:84% So this may be very attractive for mass-immunization 00:09:48.500 --> 00:09:50.930 align:middle line:84% campaigns, particularly in lower and middle-income country 00:09:50.930 --> 00:09:51.430 align:middle line:90% setting. 00:09:51.430 --> 00:09:55.030 align:middle line:84% And it has been the major strategy for the Global Polio 00:09:55.030 --> 00:09:58.220 align:middle line:84% Eradication Initiative in recent times. 00:09:58.220 --> 00:10:01.140 align:middle line:84% But of course, it also has some disadvantages. 00:10:01.140 --> 00:10:05.540 align:middle line:84% So even though the vaccine is relatively inexpensive, 00:10:05.540 --> 00:10:08.150 align:middle line:84% we also know that it has a lower dose 00:10:08.150 --> 00:10:12.290 align:middle line:84% efficacy than the injectable vaccine, in many contexts. 00:10:12.290 --> 00:10:14.530 align:middle line:84% So that is to say that the ability-- 00:10:14.530 --> 00:10:17.700 align:middle line:84% the effect which the vaccine is able to produce 00:10:17.700 --> 00:10:20.260 align:middle line:84% and it seeds production of immune properties 00:10:20.260 --> 00:10:24.960 align:middle line:84% in the individual, it's lower compared to the injectable. 00:10:24.960 --> 00:10:28.580 align:middle line:84% So therefore, you need more doses on the oral polio vaccine 00:10:28.580 --> 00:10:32.450 align:middle line:84% in order to achieve immunity in the individual. 00:10:32.450 --> 00:10:35.060 align:middle line:84% And then, again, even though the vaccine, 00:10:35.060 --> 00:10:37.805 align:middle line:84% the live vaccine in the oral polio vaccine-- 00:10:37.805 --> 00:10:41.960 align:middle line:84% the live virus in the oral polio vaccine has been attenuated. 00:10:41.960 --> 00:10:44.450 align:middle line:84% That is to say, it has been changed in a way 00:10:44.450 --> 00:10:49.250 align:middle line:84% that it's less likely to lead to an infection or virulence 00:10:49.250 --> 00:10:51.230 align:middle line:90% within the individual. 00:10:51.230 --> 00:10:53.750 align:middle line:84% We know that in rare cases, there is what we'll call 00:10:53.750 --> 00:10:57.060 align:middle line:84% "vaccine-associated paralytic poliomyelitis," 00:10:57.060 --> 00:11:01.460 align:middle line:84% which can occur when, over the course of application, 00:11:01.460 --> 00:11:06.860 align:middle line:84% the virus in the vaccine can regain its virulence factor. 00:11:06.860 --> 00:11:10.155 align:middle line:84% That is, it kind of regains its ability to cause harm, 00:11:10.155 --> 00:11:13.070 align:middle line:84% to cause paralysis, in an individual. 00:11:13.070 --> 00:11:15.820 align:middle line:84% And this is really significant because in the recent times, 00:11:15.820 --> 00:11:18.290 align:middle line:84% we've found out that these changed 00:11:18.290 --> 00:11:21.410 align:middle line:84% viruses within a vaccine can continue to circulate 00:11:21.410 --> 00:11:23.380 align:middle line:90% in the environment, right? 00:11:23.380 --> 00:11:25.950 align:middle line:84% And over the course of circulation in the environment, 00:11:25.950 --> 00:11:29.180 align:middle line:84% it can continue to gain more virulence and capable 00:11:29.180 --> 00:11:30.445 align:middle line:90% of causing paralysis. 00:11:30.445 --> 00:11:32.570 align:middle line:84% And this has been sometimes called the "circulating 00:11:32.570 --> 00:11:34.790 align:middle line:90% vaccine-derived polioviruses." 00:11:34.790 --> 00:11:38.080 align:middle line:84% So the oral poliovirus, in and of itself, as a [INAUDIBLE] 00:11:38.080 --> 00:11:41.823 align:middle line:84% in very rare cases can cause paralysis in some individuals, 00:11:41.823 --> 00:11:43.990 align:middle line:84% but grant it, individuals who are immunocompromised, 00:11:43.990 --> 00:11:46.010 align:middle line:84% individuals who, for some reason, who 00:11:46.010 --> 00:11:47.360 align:middle line:90% have very low immunity. 00:11:47.360 --> 00:11:49.820 align:middle line:84% And in other cases, it can change. 00:11:49.820 --> 00:11:53.450 align:middle line:84% The virus and the vaccine can change in the intestine. 00:11:53.450 --> 00:11:55.400 align:middle line:84% And it can be shed into the environment. 00:11:55.400 --> 00:11:59.680 align:middle line:84% And that circulating virus can again, cause paralysis 00:11:59.680 --> 00:12:01.650 align:middle line:90% within the human population. 00:12:01.650 --> 00:12:04.100 align:middle line:84% So again, a bigger challenge that the Global Polio 00:12:04.100 --> 00:12:06.920 align:middle line:84% Eradication Initiative faces right now, 00:12:06.920 --> 00:12:10.120 align:middle line:84% is as a result of some of these disadvantages. 00:12:10.120 --> 00:12:12.380 align:middle line:84% So we have instances right now, where 00:12:12.380 --> 00:12:14.890 align:middle line:84% we have more cases of circulating 00:12:14.890 --> 00:12:18.560 align:middle line:84% vaccine-derived polioviruses, which are the result of use 00:12:18.560 --> 00:12:22.760 align:middle line:84% of the oral polio vaccine, are common all over the world, 00:12:22.760 --> 00:12:25.550 align:middle line:84% even much more than the wild infection 00:12:25.550 --> 00:12:29.150 align:middle line:90% due to the wild poliovirus. 00:12:29.150 --> 00:12:31.590 align:middle line:84% And then, for the injectable polio vaccine, 00:12:31.590 --> 00:12:33.540 align:middle line:84% which it contains the killed virus, 00:12:33.540 --> 00:12:35.380 align:middle line:84% the immediate advantages is that there 00:12:35.380 --> 00:12:38.620 align:middle line:84% is no risk of vaccine-associated paralytic polio. 00:12:38.620 --> 00:12:40.870 align:middle line:84% So that is that the vaccine, in and of itself, 00:12:40.870 --> 00:12:43.100 align:middle line:90% cannot cause paralysis. 00:12:43.100 --> 00:12:45.645 align:middle line:84% Right, just-- we said that the OPV, the vaccine, 00:12:45.645 --> 00:12:48.180 align:middle line:84% administered to an individual can cause [INAUDIBLE] 00:12:48.180 --> 00:12:51.090 align:middle line:84% the risk of paralysis in the individual that 00:12:51.090 --> 00:12:52.650 align:middle line:90% receives the vaccine. 00:12:52.650 --> 00:12:55.570 align:middle line:84% And that also, the risk of a modification to the virus 00:12:55.570 --> 00:12:57.960 align:middle line:84% and the vaccine in the intestine of the individual, which 00:12:57.960 --> 00:12:59.502 align:middle line:84% is shared into the environment and we 00:12:59.502 --> 00:13:01.200 align:middle line:84% can circulate in the environment. 00:13:01.200 --> 00:13:04.530 align:middle line:84% And it'll cause the circulating vaccine-derived polioviruses, 00:13:04.530 --> 00:13:06.990 align:middle line:84% as is seen among human population. 00:13:06.990 --> 00:13:12.310 align:middle line:84% All of this does not exist with the injectable polio vaccine. 00:13:12.310 --> 00:13:15.330 align:middle line:84% And again, it produces more effective immunity 00:13:15.330 --> 00:13:16.460 align:middle line:90% in an individual. 00:13:16.460 --> 00:13:20.730 align:middle line:84% So it doesn't require the amount of the-- the per dose efficacy 00:13:20.730 --> 00:13:23.690 align:middle line:84% for the injectable polio vaccine is actually higher 00:13:23.690 --> 00:13:26.130 align:middle line:90% than the oral polio vaccine. 00:13:26.130 --> 00:13:27.910 align:middle line:84% But the disadvantage is the cost. 00:13:27.910 --> 00:13:30.910 align:middle line:84% So it's really expensive, relative to the OPV. 00:13:30.910 --> 00:13:34.860 align:middle line:84% And there are limited capacity to really produce it rapidly 00:13:34.860 --> 00:13:37.490 align:middle line:90% on scale or like the OPV. 00:13:37.490 --> 00:13:41.070 align:middle line:84% And then again, it also requires it to be administered 00:13:41.070 --> 00:13:42.290 align:middle line:90% by a trained health worker. 00:13:42.290 --> 00:13:43.860 align:middle line:84% So there's that additional cost that 00:13:43.860 --> 00:13:46.267 align:middle line:84% is required, in terms of making sure 00:13:46.267 --> 00:13:48.600 align:middle line:84% that your highly-trained health worker deliver the dose. 00:13:48.600 --> 00:13:52.020 align:middle line:84% Not anybody can deliver it, unlike the OPV. 00:13:52.020 --> 00:13:55.560 align:middle line:84% So and that's why it's less suitable for mass immunization. 00:13:55.560 --> 00:13:59.250 align:middle line:84% But clearly, in resource-poor setting or low-income setting, 00:13:59.250 --> 00:14:00.950 align:middle line:84% the one we have with one poliovirus 00:14:00.950 --> 00:14:02.550 align:middle line:90% it'll still be endemic. 00:14:02.550 --> 00:14:04.190 align:middle line:84% And then, it require hold of supplies, 00:14:04.190 --> 00:14:05.830 align:middle line:84% so like consumables, like sterile 00:14:05.830 --> 00:14:08.430 align:middle line:90% needles to administer it. 00:14:08.430 --> 00:14:10.920 align:middle line:84% And then again, experience, I know some parents are just 00:14:10.920 --> 00:14:12.487 align:middle line:90% very hesitant to injection. 00:14:12.487 --> 00:14:14.820 align:middle line:84% I mean, it's a different ballgame when you put something 00:14:14.820 --> 00:14:18.090 align:middle line:84% in the mouth, as compared to when you actually inject. 00:14:18.090 --> 00:14:21.240 align:middle line:84% And in some cases, you know that injection, in and of itself, 00:14:21.240 --> 00:14:23.263 align:middle line:84% can [INAUDIBLE] associated with increasing 00:14:23.263 --> 00:14:25.680 align:middle line:84% the risk of paralysis for people that have been previously 00:14:25.680 --> 00:14:27.390 align:middle line:90% exposed to the wild poliovirus. 00:14:27.390 --> 00:14:29.670 align:middle line:84% So again, this is all disadvantages. 00:14:29.670 --> 00:14:33.850 align:middle line:84% But to declare that you would see that both of these vaccines 00:14:33.850 --> 00:14:37.100 align:middle line:84% have their role and their relevance in an eradication 00:14:37.100 --> 00:14:37.740 align:middle line:90% initiative. 00:14:37.740 --> 00:14:41.880 align:middle line:84% So for instance, we know that the injection mode really 00:14:41.880 --> 00:14:44.370 align:middle line:84% was credited for actually helping the United 00:14:44.370 --> 00:14:47.340 align:middle line:84% States to eliminate the epidemics of poliovirus 00:14:47.340 --> 00:14:48.570 align:middle line:90% and rapidly. 00:14:48.570 --> 00:14:52.290 align:middle line:84% Much later, the oral polio vaccine came on board. 00:14:52.290 --> 00:14:54.450 align:middle line:84% But in low and middle-income country setting, 00:14:54.450 --> 00:14:58.800 align:middle line:84% the OPV has really been very helpful in rapidly scaling up 00:14:58.800 --> 00:15:02.540 align:middle line:84% a mass immunization across different context 00:15:02.540 --> 00:15:03.530 align:middle line:90% and different setting. 00:15:03.530 --> 00:15:05.250 align:middle line:84% But now, we are seeing challenges 00:15:05.250 --> 00:15:07.680 align:middle line:84% with the circulating vaccine-derived polioviruses, 00:15:07.680 --> 00:15:09.780 align:middle line:84% which was a complication of the oral poliovirus. 00:15:09.780 --> 00:15:13.110 align:middle line:84% So again, and really a need for use of the injectable 00:15:13.110 --> 00:15:16.385 align:middle line:84% polio vaccine, which is what is under way 00:15:16.385 --> 00:15:18.510 align:middle line:84% in a lot of low and middle-income country settings. 00:15:18.510 --> 00:15:20.490 align:middle line:84% So you really do need both in order 00:15:20.490 --> 00:15:24.050 align:middle line:90% to achieve the eradication goal. 00:15:24.050 --> 00:15:26.810 align:middle line:84% Because your have three different strains 00:15:26.810 --> 00:15:29.080 align:middle line:84% of wild polioviruses-- you have type 1. 00:15:29.080 --> 00:15:31.700 align:middle line:84% You have type 2, and you have type 3-- 00:15:31.700 --> 00:15:34.160 align:middle line:84% the vaccine are produced in a way 00:15:34.160 --> 00:15:36.790 align:middle line:84% that they can address each of the strains. 00:15:36.790 --> 00:15:39.260 align:middle line:84% So you have the monovalent vaccine, 00:15:39.260 --> 00:15:42.710 align:middle line:84% which targets a single strain of the wild poliovirus. 00:15:42.710 --> 00:15:47.060 align:middle line:84% You could have the monovalent oral polio vaccine type 1, 00:15:47.060 --> 00:15:49.430 align:middle line:84% or monovalent oral polio vaccine type 2, 00:15:49.430 --> 00:15:52.160 align:middle line:84% or monovalent oral polio vaccine type 3. 00:15:52.160 --> 00:15:54.350 align:middle line:84% And then, you could also have bivalent, 00:15:54.350 --> 00:15:56.690 align:middle line:84% which really can actually-- vaccine 00:15:56.690 --> 00:16:00.350 align:middle line:84% that can address two strains of the wild poliovirus. 00:16:00.350 --> 00:16:02.840 align:middle line:84% And then, you have the trivalent, 00:16:02.840 --> 00:16:04.860 align:middle line:84% which combines a vaccine that can 00:16:04.860 --> 00:16:10.290 align:middle line:84% address the three different strains of the wild poliovirus. 00:16:10.290 --> 00:16:12.140 align:middle line:84% And we know that, even as we speak, 00:16:12.140 --> 00:16:16.930 align:middle line:84% that efforts are underway to produce other types of vaccines 00:16:16.930 --> 00:16:18.810 align:middle line:90% that are more stable. 00:16:18.810 --> 00:16:21.950 align:middle line:84% It's particularly an oral polio vaccine that are more stable, 00:16:21.950 --> 00:16:27.200 align:middle line:84% with less likelihood of gaining virulence. 00:16:27.200 --> 00:16:30.020 align:middle line:84% So that it can be used to address 00:16:30.020 --> 00:16:34.250 align:middle line:84% the scourge of the circulating vaccine-derived polioviruses, 00:16:34.250 --> 00:16:39.860 align:middle line:84% as a result of the use of the OPV, the oral polio vaccine. 00:16:39.860 --> 00:16:42.910 align:middle line:90% [MUSIC PLAYING] 00:16:42.910 --> 00:16:47.000 align:middle line:90%