Measles outbreaks are often blamed on the fact that vaccines have been so successful people forget how dangerous this disease is. They allow themselves to become complacent or manipulated by antivaccine fearmongering. Vaccination coverage drops and inevitably outbreaks occur. But now with a sudden global spike in measles cases – increasing by nearly a third after years of steady decline and resulting in 110,000 deaths – forgetting is less and less the issue.
Much of this increase is due to the collapse of health systems in Venezuela, but the growing number of cases in Europe, which has seen cases increase by more than 450 per cent, and North America is also a major cause for concern, not least because we now have generations of parents who grew up having never seen measles first-hand. This begs the question of how we engage and communicate the importance of vaccination to a growing number of people who have no memory of the disease at all.
People often talk of measles being a harmless disease, but it is far from it. As recently as the 1980s it killed more than 2.5 million people every year, mainly children. Those who survived risked permanent blindness or brain damage. And even with the best health systems, a small percentage of cases lead to the brain basically dissolving with no possible treatment. It is also one of the most contagious diseases ever known. It is so infectious that it is possible to catch it from someone just by entering the same room, even hours after they have left.
This is one reason why it is so important for vaccine coverage to stay at 95 per cent or above. Compared to other diseases this is relatively high, but given the infectiousness, necessary in order to maintain herd immunity, where enough of the population is protected to prevent the spread of the virus. As soon as it drops below this level, outbreaks are inevitable.
In fact, it’s not just the proportion of children that counts, it’s also important when they are vaccinated. Last year in the UK, for example, 95 per cent of five-year-olds had received at least one shot of measles vaccine, and yet since then in 2018 so far there have been nearly 1000 cases. One reason for this is that at age two, just 92 per cent of children were protected, and in the London region it was less than 90 per cent. Given that the first dose of measles is meant to be given to one-year-olds, the difference suggests that either coverage is beginning to dip or parents may be delaying.
This needs to stop because it puts younger children at risk as well as people who cannot be vaccinated, such as those with compromised immune systems. It effectively creates a window of opportunity for the virus, helping to perpetuate its existence, and not just locally but globally too. That’s because measles knows no borders and is adept at international travel. Often outbreaks in the US can be traced back to unvaccinated people travelling overseas and bringing back the virus.
And it works both ways. In 2009 the medical journal the Lancet reported that cases of measles had been exported from Europe to poorer countries in Latin America, a region that had previously eliminated the disease. The difference being that while parents in Europe may have chosen for their children not to be vaccinated, that choice is putting vulnerable children in poor countries in mortal danger because for them the high levels of malnutrition and limited healthcare make the virus far more lethal.
Currently global measles coverage stands at just 85 per cent, which represents real progress on previous decades. But so long as vaccine hesitancy remains an issue in wealthy countries, that progress and any efforts towards controlling and perhaps one day eliminating this disease once and for all, will continue to be undermined.
So, the question is how do we encourage a generation of parents who have never had reason to fear measles, to stick to vaccine schedules, and without it having to result in outbreaks? As things stand, the best advocate for measles vaccine is the virus itself. Right now, many parents who have never witnessed this disease and therefore never considered it a threat, are discovering, through the misery of their children, that measles really is no picnic. This is made evident by the fact that in wealthy countries, whenever an outbreak does occur, there is usually a scramble to get vaccinated.
Part of the solution has to include better engagement with parents and in ways that doesn’t assume prior knowledge of the disease and doesn’t rely upon fear to communicate that knowledge. Because fear as a motivating factor will become increasingly less effective as the number of parents who have never known measles continues to grow.
No parent wants their child to suffer or die. And in all likelihood many of these hesitant parents are simply unaware of and would be appalled by the global impact that delaying or missing their children’s vaccinations can have on other children. These are people living in countries that have a history of generosity towards causes that support vulnerable children. Perhaps with knowledge of the positive impacts vaccination at home can have to the lives of the poorest children across the globe, we can encourage parents to take pride in vaccinating and protecting their children, and in doing so create a generation of vaccine activists who will not have to repeat history.
Seth Berkley is the CEO of Gavi, the Vaccine Alliance