By Dora Anne Mills, MD, MPH, Chief Health Improvement Officer at MaineHealth

Originally published Sunday, August 1, 2021

COVID in Provincetown

While the news about the Delta variant means we’ve taken three steps forward and now one step back, it’s not completely unexpected (see my July 11th post about Delta). Viruses constantly mutate, and those viruses that thrive are those that find the loopholes for survival, such as becoming much more contagious and being able to grow in the noses of the fully vaccinated.

Indeed, that is what has happened. For about a month, NorDx Lab (MaineHealth’s lab) has noted and reported to government authorities high viral loads among some who are fully vaccinated and infected. Screening tests NorDx has conducted indicate these cases are all the Delta variant.

Then, Provincetown exploded. Provincetown, or Ptown, is at the very tip of Cape Cod and known as: the home of the Wampanoag and Nauset Tribes; the first place the Pilgrims from the Mayflower landed in 1620 escaping Europe for religious freedom (and signed the Mayflower Compact while moored in the harbor); a Portuguese fishing village; America’s oldest art colony; and an LGTBQ+ resort town.

It also has a rich public health history. During the 1918 pandemic, the Universalist church was converted into a hospital. During the early days of the AIDS pandemic in the 1980s, when many suffering from the then-untreatable disease were shunned by their families, Provincetown welcomed and cared for them. The town became a model of a community coming together during a crisis to care for one another, which I understand they have continued to do during the current COVID-19 pandemic.

The town has boasted a COVID-19 vaccine rate of 114% of the eligible population age 12 and older. How can a vaccine rate be over 100%? It may be that people with seasonal homes who sought refuge from the pandemic there also obtained their vaccines there. Because residency status for tax and census purposes is different than what was used to determine eligibility for vaccination, out-of-state residents could also often get vaccinated in a town if they owned property there, and get counted in the numerator but not the denominator. Also, the census population figures used for the denominator are old enough to not reflect an influx of residents from the last several years.

Regardless, by June, Provincetown had a very high vaccination rate. The two-week COVID case rate was zero. Government restrictions on masking and gathering had been lifted in May, and US CDC issued recommendations in mid-May that fully vaccinated people did not have to mask.

Clearly, Provincetown was ready for the summer of freedom from the pandemic. The year-round population of 3,000 swelled to an estimated 60,000, a usual number for pre-pandemic days.

After the crowded July 4th weekend celebrations, during which many had to take refuge indoors because of heavy rains, COVID cases started climbing. They climbed among the unvaccinated as well as the vaccinated. With such a large proportion of the population vaccinated, an increasing number of breakthrough cases is expected (since, for instance, a 5% breakthrough of a larger number of vaccinated is a bigger number than 5% breakthrough of a smaller number of vaccinated).

However, what was highly unusual is that viral loads in the nasal swab samples from some of the vaccinated who were infected were noted to be about the same as the viral loads among those who were unvaccinated. With some phenomenal community-based contact tracing, led by Massachusetts’ Community Tracing Collaborative, public health officials have been able to determine that there was likely transmission of disease among the fully vaccinated.

The town manager is now reporting almost 900 cases tied to this outbreak, including some visitors who reside out of state. US CDC reports 469 cases tied to the outbreak among Massachusetts residents, with 74% having occurred in fully vaccinated persons. 90% of the specimens tested for variants show this to be the Delta variant. Among the five who have been hospitalized, four were fully vaccinated, and two of them have significant underlying conditions.

As challenging as these numbers seem, it appears with such high vaccination rates (in the town and among Massachusetts residents, which has been tied for the second-highest rates in the country this last month), that given the proportions, the probability of one getting infected from this outbreak was much much higher if one was unvaccinated.

As of two weeks ago, the town issued a mask advisory for all indoor public places, and as of a week ago, that morphed into a mandate.

As a result of the Provincetown outbreak and reports such as from NorDx Lab of high viral loads among some who are fully vaccinated and infected with the Delta variant, the US CDC issued a recommendation last week that those living in counties with high or substantial transmission mask when indoors in public places.

For those living in counties with low or moderate transmission, the recommendation is for masking for those with a weakened immune system, or who are at increased risk for severe disease, or if someone in the household has a weakened immune system or is at increased risk for severe disease or is unvaccinated.

Several items to note:

  • The new US CDC recommendations, which are in large part a result of the Provincetown outbreak, would not have prevented the Provincetown outbreak since the town at the time of the instigating July 4th festivities not only had low transmission, but had no recorded cases for at least two weeks.
  • The metrics used to determine county levels of transmission – incidence and test positivity rates – use excellent methodology. However, because of narrow ranges between the four levels of transmission (low, moderate, substantial, and high) and because they use 7-day rolling averages updated daily, the levels of transmission can easily change and even bounce around, especially in rural counties. We’ve already seen this in Maine, with county transmission levels changing daily, with resulting changes in masking recommendations.
  • The US CDC categories – categories of counties with high or substantial transmission and categories of people who are recommended to mask regardless of county transmission rates – apply to a very large proportion of the U.S. population, which means the US CDC recommendations are close to universal masking in indoor public places.
  • Masking is already mandated by federal regulations for healthcare settings and public transportation. Universal masking is recommended by US CDC for school settings.
  • US CDC and OSHA have not issued recommendations for indoor private places such as non-public offices and workplaces that are not schools, healthcare, or transportation.

So, what should we all do? Besides adhering to required masking such as in transportation and healthcare settings, my litmus all along has been: do I want to share breathed air with people I’ll be with? And I’m a strong advocate of turning the dials of masking, distancing, and ventilation up and down.

  • If I’m with close friends and family who are fully vaccinated and healthy, I am unlikely to mask.
  • If I’m headed into a crowded supermarket, I mask.
  • If I’m planning to meet with a variety of people whose vaccine status I don’t know (but are likely vaccinated), then I’ll also examine ventilation of the venue (can we open the windows or sit outside?) and maintain at least six feet distance.

For me, there are not many changes. Delta has been known for a number of weeks to be a different virus. The vaccines are still working to protect against hospitalization and other forms of severe COVID, but Delta can break through our immunity from vaccine more easily to cause non-severe illness. With this said, the chances of getting ill from COVID, and especially severely ill, are much higher if someone is unvaccinated, and that appears true from the data we see from the Provincetown outbreak as well. Indeed, at MaineHealth, almost all of those hospitalized with COVID-19 are unvaccinated.

I think we’re moving toward a time when we’ll look at COVID and influenza as we do the weather. Just as we glance at the morning’s weather forecast to determine if we should wear a raincoat and take an umbrella with us, we may have an app or a routine report on the status of respiratory illness in our communities. Unlike the weather, I would hope the respiratory illness forecasts don’t change daily. But with such forecasts, we’ll be able to decide to what degree to mask, distance, and pay attention to ventilation.

Right now, with the Delta variant’s increased contagiousness, virulence of disease, and with some immune evasion, coupled with increasing incidence of COVID and test positivity rates across Maine, the forecast is for some rain. As a result, I’m masking, distancing, and paying attention to ventilation more stringently, in addition to myself being vaccinated and assessing the vaccination status of those around me (since even with the challenges with Delta, the unvaccinated are much more likely to become infected).

Yes, we’ve taken a step back with Delta. But over these last few months, we’ve also taken several major steps forward. I’m still enjoying the summer and feel much more protected being vaccinated than I did last summer when we were all unvaccinated. And we now have more solid evidence behind the supplementary tools of masking, distancing, and ventilation.

Whether one is in Provincetown or in Maine, it’s vacationland and vacation time, a time to rest, relax, and relish.

Sources