A little over a year ago, I wrote about a measles outbreak in Ohio in the context of increasing concerns of the pandemic’s effect on vaccination rates around the world:
During the peak of the pandemic, when people were trying to stay home and avoid COVID-19, millions of children got behind on their routine immunizations. This was, and is, a worldwide phenomenon. The WHO recently estimated that 40 million children missed a dose of the measles vaccine in 2021 alone, putting them and potentially millions more around them at risk of developing this potentially deadly disease.
In addition to lack of access, the pandemic has also appeared to fuel a wave of anti-vaccine sentiment in the United States. Being against routine childhood immunization, something that has saved countless lives and prevented suffering in so many innocent children, is becoming a plank in the GOP platform. This growing number of people that are wary of vaccines is adding to the number of children who will not be protected from vaccine-preventable illnesses.
The 2022-2023 Ohio outbreak ended up putting 36 children in the hospital with 85 total measles infections. Every single infected child was not fully vaccinated, which makes sense given how amazingly effective (and safe) the vaccine is. There were no deaths during that outbreak, though it is only a matter of time. And because of the nature of measles infections, which can lie dormant and cause death years later in a small but very real percentage of cases, we can’t say with certainty that all of these children are safe.
Though some improvements in vaccination rates around the world were seen in 2022, the issues with vaccine availability, hesitancy and refusal, in many cases fueled by blatant anti-vaccine propaganda, is still a big problem. 2023 data likely won’t be available for a few months, but it is safe to say that millions of children were left at risk of this potentially debilitating and even life-threatening disease and many thousands will end up dying because of it. Certainly there will be some regions with lower rates of vaccine uptake, but every region, and every community, will continue to have problems.
A perfect example of this is currently impacting Philadelphia, which has an overall measles vaccination rate of 93%. That may sound good, but 95% is necessary in order to achieve herd immunity against measles in a community. With such a contagious virus, having 7% of children unprotected means that there are enough for outbreaks to occur, particularly if social factors result in clumping of unprotected children in specific schools, churches, or other groups. It is important to remember that even with higher vaccination rates, any unlucky at-risk individual could still be at the wrong place at the wrong time.
As of yesterday, 9 cases of measles have been reported in Philadelphia in the past month. The index case was a young child who had recently visited a high risk country and was subsequently hospitalized. It wasn’t until 2 days after their admission that he was diagnosed with measles, however, and two others were infected before appropriate containment was initiated. One of these was an infant too young to have received the MMR vaccine and the other, an older child, was unvaccinated. That child’s unvaccinated parent also became ill.
The additional cases occurred because one of the infected children was sent to daycare in violation of quarantine recommendations. The most recent reported case is the fifth originating at the daycare. So far, 6 of the 9 cases have required hospitalization but they have all been discharged home. But it’s early. An outbreak can’t be considered over until two incubation periods have passed since the last case, so about 40 days.
The measles virus can remain airborne and infectious for 2 hours, so close contact isn’t required. Simply getting into the wrong elevator is enough. Fairly nonspecific flu-like symptoms in a non-immune individual can take up to 2 weeks to appear, but the classic rash can take another 3-5 days. This means that it is very easy to be out and about in a community without realizing that you have measles, and you are able to spread the disease for a few days prior to, and a few after, the rash appears. Most people recover uneventfully, but severe lung disease and inflammation of the brain can occur (and is more common in young children), with the overall mortality rate for measles being about 1-2 per 1000.
Things are much worse in across the pond. Europe reported more than 30,000 cases of measles last year, a massive 30-fold increase from 2022. Currently England, specifically the West Midlands area, is the epicenter of measles in the region with an ongoing outbreak of at least a couple hundred cases, 50 of which required admission to a hospital for care. Numbers are higher in other regions, particularly the Middle East and Africa. Overall, 136,000 deaths were caused by measles in 2022, an increase of 43%. And again, there is a general expert agreement that this is all the result of significant decreases in vaccine rates during the early years of the pandemic.