How is measles motivating policy change?
In August 2019, the UK lost its ‘measles-free’ status. More recently, the first case of polio in 27 years was documented in a 3-year-old boy from Malaysia. There is concern that we will see a rise in frightening news headlines like these if appropriate action isn’t taken. These cases have fuelled discussions about the decline in uptake of vaccines (which could prevent these reported cases) and the possibility of introducing new vaccine policies which may help stop preventable problems like this happening in the future. Strikingly, the World Health Organisation (WHO) has stated that vaccine hesitancy is in the top 10 list of global threats. So what does it really mean to lose the ‘measles-free’ status? This is appointed by the WHO and is defined as an area or a country that has had no regular transmission of the infection in that designated area in 12 months1. The UK was given it’s ‘measles-free’ status in 2016, successfully maintaining it for less than four year.
The rise in measles cases, and the loss of the ‘measles-free’ status in the UK, Greece and several other countries in Europe and around the world, may have been caused by multiple factors. Firstly, with measles ‘under control’, it is thought that people have forgotten how serious and life-threatening measles can be. The measles virus is, in fact, one of the most infectious diseases on the planet. Symptoms include fever, light-sensitivity and a rash, which in most cases subside in a week to 10 days2. However, in some individuals, there can be complications which can prove fatal. Additionally, measles infection has a significant impact on the immune system in the short and long-term. In the first instance, measles decreases the number of white blood cells in the body. It is these cells which are responsible for fighting other infections. This means during measles infection, individuals will be more vulnerable to other pathogens. In the longer-term, a recent study has shown that measles can impact immunological memory3.
This study involved sequencing antibody genes from children before and after measles infection. It was found that memory immune cells, trained to recognise and fight secondary infection, were absent from the blood in children after measles. It was also found that the immune system was more immature post-measles infection which means other diseases the child had not yet been exposed to would also be more difficult to develop immunity against. This study has shown that a vaccine against measles infection is not only protection against measles itself, but against the many other infections a person may be exposed to in their lifetime.
It is also important to remember that it is the most vulnerable populations in society that are at the highest risk of getting infected. Young babies, the elderly and people who are immunocompromised, who cannot get vaccinated themselves, are reliant on the rest of the population being vaccinated and keeping the disease in the population low.
Another reason attributed to the rise in measles cases is the misinformation and disinformation spread surrounding the safety and efficacy of vaccines. Research from the Netherlands demonstrates the exponential damage a rise in measles can have and the importance of large vaccine coverage in a population. The MMR vaccine, protecting against measles, mumps and rubella, is 97% effective after 2 doses, and 93% after only 1 dose4. Yet, a discredited study from 1998 regarding this seems to stick in people’s minds. Andrew Wakefield published a paper in a well known medical journal linking the MMR vaccine to autism. There have been many articles since showing there is no link and the paper has been retracted, with Wakefield being found guilty of fraud. Additionally, a lot of mistrust may come from disproportionate reporting in the media.
Up until recently, measles cases were rare and therefore the frightening symptoms
were not talked about regularly. Yet a rare side effect, such as an allergic reaction from a vaccinated child, could gain a lot of media coverage and fuel the anti-vaccination movement. In the case of the Wakefield study, it gained a lot of media coverage at the time, despite the very small sample size in the study as well as other questionable methods used. 20 years on, social media makes the spread of misinformation and disinformation even easier. One study has revealed that 50% of parents with children under 5 came across negative messages regarding vaccination online5. And another study has reported that much of this messaging comes from online bots, that can churn out an alarming rate of misinformation per hour6. With the levels of misinformation appearing only to be on the rise, something needs to be done to counteract the damage. One such method that has been suggested to tackle this, is a change in vaccine policy.
In the UK currently vaccines are not compulsory, however, the policies surrounding vaccines have varied considerably over the last 2 centuries7. In 1853, a vaccine against smallpox was made compulsory for all children under 3 months. Non-compliant parents were subject to a fine. This rigorous vaccine campaign was hugely successful, resulting in the elimination of smallpox first from the UK, and globally in 1990. As such, in 1873, all vaccination was made compulsory, with fines or even risk of arrest for parents who did not comply. Yet, records suggest that the compulsory nature of vaccination discouraged parents. In the 1870s, anti-vaccination movements began to rise, with an anti-vaccination rally in Leicester in 1885 attracting over 100,000 people. Leicester was chosen as the rally site based on the fact people believed the locals had an alternative strategy to vaccination. This involved quarantine of those affected and the healthcare professionals in charge were vaccinated themselves, providing a protective gate effect. The reasons parents were wary about vaccination varied, from the use of cow protein in the vaccines, which was a difficult concept for people to understand scientifically and religiously, to mistrust about how smallpox was transmitted and therefore the need for vaccination at all8.
From a health point of view, vaccination in the 1800s was certainly more dangerous than it is now due to the technology available and legislation around health care providers and people did die as a result. However, as is true now, the benefits for most far outway the risks. After years of protests from Leicester and beyond, in 1898 there was an amendment made to the vaccination act that removed the fines for non-compliance. This policy gave parents the right to choose what they deemed safe for their child. This was subject to an application to magistrates to gain an exemption certificate, which had to be approved before a child was 4 months old. However, there were often delays, or exemptions not granted which meant in 1907, another act was passed that removed the need for an exemption certificate making it even easier for parents to make the decision not to vaccinate.
The WHO are not responsible for suggesting the means by which countries can increase the vaccination uptake and different countries take a variety of approaches. Australia offers a financial incentive for complying with vaccines – parents choosing to vaccinate their children will be given two payments of $129 Australian dollars when children complete their vaccinations in 2 age brackets9. Within the US, policies vary from state to state. Vaccines are compulsory, however, exemptions are granted on various grounds including religion or philosophical beliefs as well as medical reasons. Studies have shown that the easier it is to file for an exemption from mandatory vaccination, the more people will apply for such exemption. Slovenia also has compulsory vaccination programmes yet this country is a good example that demonstrates the benefits mandatory vaccination can have on compliance. Vaccination against 9 diseases, including polio and tuberculosis, are compulsory and the country has achieved a 95% compliance rate. Conversely, the human papillomavirus (HPV) vaccination is non-mandatory and unfortunately has a compliance rate of less than 50%.
It appears that the vaccine policy landscape across the globe is extremely varied and it’s not a one size fits all approach. So what approach should the UK take? There have been discussions in the last year with the health secretary that there will be a take on a ‘no jab, no school’ policy. This would mean children without compulsory vaccines, for diseases including measles, would be unable to attend school (where diseases like measles are likely to spread). France has implemented a policy similar to this – children have 11 compulsory vaccines, without which they cannot attend school. This was mandated in 2018, an increase in 9 compulsory vaccinations. Non-compliance can result in a fine or imprisonment.
Italy, who suffered 37% of all measles deaths in Europe between January 2016 and June 2017, also has a policy which states school attendance is reliant on vaccine compliance10. When enrolling children in preschools or schools run by the state, proof of vaccination will be required. If this can’t be provided, parents will be fined. The success of these campaigns has been difficult to establish so far. In France, there is no central hub for collecting data on vaccine uptake, so it may take some time before success can reliably be measured. In Italy, since the compulsory vaccine mandate, vaccination rates for MMR and polio have increased. However, there are concerns about access to vaccines across the country which may require improvements in infrastructure and funding, if the mandate is to be a true success.
A recent study has tried to answer the question of the effectiveness of these policies on vaccine uptake and disease prevention in high-income countries11. This study noted that these countries pose a significant challenge, as there is a higher proportion of elderly individuals than in lower-income countries. This means there is a higher level of the population susceptible to measles or other diseases if there is an outbreak, meaning high vaccine coverage is crucial. The research took the approach of computationally modelling the levels of measles immunity in seven countries between 2018 and 2050 based on various methods to increase vaccine compliance. They showed that the numbers of measles-susceptible individuals would increase in all countries studied if no changes to policy were made. The results from this study suggested that by adjusting current methods measles would be eliminated in the UK, Ireland, the US and Italy but not Singapore and South Korea. The research also suggested that focusing efforts on implementing policies for compulsory vaccination was not enough and educational programmes for adults would be needed.
At the moment, the measles virus is gaining increasingly more power. Vaccines themselves are incredibly effective if they are used, there just needs to be a better way to enable this. So whether it be a new policy, adult education programmes, a way to stop misinformation spread or a combination of all of these let’s hope that a successful strategy is found sooner rather than later.
This article was specialist edited by Anna Andrusaite and copy edited by Ailish McCafferty.