The holidays are fast approaching which means millions of people will be traveling. Unfortunately, this busy travel season can also amplify the spread of infectious diseases like influenza and measles.
Outbreaks of measles have become increasingly common in recent years with the growth of anti-vaccine groups and attitudes. The ongoing measles outbreak in Samoa is a prime example of when anti-vaccine ideologies take hold of isolated areas and herd immunity plummets.
Recent estimates put the outbreak on the small island at over 5267 cases
with 73 associated deaths. Vaccination rates had dropped dramatically over the years, and were recently estimated at 31% prior to response efforts
. The herd immunity threshold for measles is 93-95%,
which means that the low rates of vaccination in Samoa were essentially a ticking time bomb.
Thankfully, response efforts have gotten the islands vaccination rate up to 93%, which will hopefully slow the deadly outbreak. Currently, the island continues to be in a state of emergency, which was first declared in mid-November. The government has barred children 0-14 years of age from attending public gatherings and requires children of that age to also show proof of immunization prior to boarding inter-island ferries.
The government has also closed its offices (with the exception of public utilities) so that civil servants can aid in the response efforts. Response efforts have continued to pour in to help halt this devastating outbreak. The population of Samoa is just over 196,000 individuals and when there are more than 5000 cases, more than 2.6% of the population have been infected.
So how did Samoa get to this point? Anti-vaccine advocates have played a large role, so much so that arrests have been made. These include charges and arrests for “incitement against government order” for outspoken anti-vaccine advocates like Edwin Tamasese
. Even during his arrest, Tamasese continued to spout misinformation. A compounding factor was the 2018 death of 2 infants following their vaccination sparked fear and encouraged vaccine hesitancy, despite 2 nurses pleading guilty to manslaughter
. Coupled with lax government vaccination efforts, it is not surprising this became a perfect storm for an outbreak.
Measles is a highly contagious and poses a public health threat. The 2017 outbreak in Minnesota
is a prime example of the implications of declining vaccination coverage in communities and the role anti-vaccine advocates have played in targeting them. Responding to these outbreaks is especially challenging when vaccine hesitancy plays a role as the socio-cultural components require more than just setting up vaccination clinics.
Education and community outreach is critical, but also understanding what drove the decline of vaccination rates is important so that response can be personalized to meet the needs of the community. Samoa is an example of an isolated community that has experienced significant tragedy in the face of declining coverage and widespread vaccine hesitancy. As outbreaks like this become increasingly common, we should see this as a lesson in the socio-cultural dynamics of public health and epidemiology. Hopefully Samoa will be the last example of the dangers of vaccine hesitancy and encourage other vulnerable communities to ensure their herd immunity is adequate.