Everyone seems to be asking about a possible COVID-19 vaccine: will a vaccine be developed? When? How effective will it be? However, ironically, COVID-19 is causing a large drop in uptake for existing vaccines that protect our population from equally, or more dangerous, infectious diseases.
The United States almost lost its measles elimination status last year
2019 was a bad year for vaccine preventable disease (VPD) outbreaks in the US – with ongoing measles outbreaks from New York to Michigan to Washington, which nearly cost the US its measles elimination status (which was granted in 2000). Elimination status requires no circulating measles transmission chains for a year or more, and coming close to losing that elimination status indicates we are at risk of endemic transmission, which would result in far more cases and deaths from measles. However, measles is not the only preventable disease making an unwelcome comeback.
COVID-19 is further reducing childhood vaccination rates
Reduced rates of vaccination and rising rates of non-medical vaccine exemptions make it more likely that VPDs will re-emerge, threatening to increase health care burden and cause avoidable deaths from diseases for which there are effective vaccines. COVID-19 is making matters worse as people avoid hospitals and routine outpatient visits, and most current care occurs via telemedicine, a format that doesn’t allow for vaccinations to be administered. The New York Times reported that MMR (measles-mumps-rubella) vaccination rates have dropped by 50%, pertussis vaccinations dropped by 42%, and HPV vaccinations by almost 75% compared to this time last year. This is a widespread phenomenon, with news outlets in Virginia and Miami reporting similar findings.
What happens when we re-open with low vaccination coverage?
This decrease in vaccination rates might not seem like too serious of a problem – after all, everyone is staying home. However, if states start to re-open and contact picks up again, cases of preventable diseases could spread, and if schools re-open in the fall and student immunization rates are too low to prevent outbreaks, VPDs could spread in addition to COVID-19. Though the burden of these diseases has been dramatically reduced by effective and widespread vaccination, if vaccination rates plummet enough, the United States could witness a devastating toll from preventable pediatric diseases like measles, pertussis, and meningitis when schools open again.
Many vaccine preventable diseases are more serious for children – in contrast to COVID-19
Unlike COVID-19, where children seem to be spared the worst of the symptoms, for some vaccine-preventable infectious diseases the worst complications are seen in young children. Measles has a low case fatality rate (the death rate among those infected) of about 0.2%, but most complications like pneumonia (which occurs in 6% of cases), and deaths are seen in those under age 5. Similarly, while pertussis is very rarely fatal, pneumonia secondary to the whooping cough can occur in 5.2% of cases, and 11.8% of cases among those under age 6 months. Diphtheria, though not commonly seen anymore due to a highly effective vaccine, has a case fatality rate of 5-10%, which is as high as 20% for those under 5 and over age 40. Finally, meningitis has a case fatality rate of 10-15%, even with appropriate treatment, and up to 1 in 5 survivors have long term complications such as hearing loss or limb amputation.
The US is not alone: vaccination rates are dropping on a global scale
This phenomenon of reduced vaccinations due to COVID-19 is not isolated to the United States. Global immunization campaigns are being suspended for measles and polio. This is perhaps especially devastating for polio, where the global polio eradication initiative (GPEI) has been working to eradicate the poliomyelitis virus (i.e. eliminate it from ALL countries) for decades. Endemic transmission only remains in three countries: Afghanistan, Nigeria, and Pakistan, but all countries employing polio preventive campaigns have had to pause these campaigns temporarily, which could allow for polio to resurge – representing a dangerous backslide against this years-long effort to eradicate the virus.
We need to plan now for the fall
This global drop in childhood vaccination rates could be especially dangerous come fall, when experts predict that COVID-19 cases will surge again, following the pattern of four common coronaviruses that typically peak in the fall and winter seasons. Such a peak in COVID-19 infections could create a perfect storm – by coinciding with flu season, which is often a time of stretched hospital capacity in a normal year. Flu and COVID occurring simultaneously would place additional burden on hospitals to provide respiratory support. In addition to efforts to increase uptake of the flu vaccine in the coming year, it is more important than ever to focus on ways to increase childhood vaccination rates so that surges in VPDs do not further stress respiratory care capacity. Outbreaks of measles, pertussis, or other infections could further overwhelm healthcare systems and cause unnecessary, preventable disease and death.