Spanish Flu vs Covid-19, which is the worst pandemic?. Farzana Prior
playgrounds and dance halls, and this kept the disease from exploding, as it did in Philadelphia.
The result is clearly visible in the diagram below.
Data sourced from: Public Health Reports, Vol 45, No 39, September 26, 1930
Interestingly, when you look at the St Louis curve, you will see two peaks in the Fall and early Winter. Once the pandemic seemed to be declining, the city rolled down its lockdown measures. It did this too early, and flu deaths increased again, and health officials locked the city down again. The third wave returned that Winter and last showed up in early 1920.
The virus likely lurked around for years thereafter, not causing pandemics (global breakouts), but seasonal epidemics (national breakouts), because more people had been exposed and had developed antibodies.
Implementing an early and effective restriction on social activities is a critical action that officials need to have the courage to take when a pandemic infiltrates.
Spanish Flu in Other US Cities
Across the cities in the United States there were a range of responses to the Spanish Flu, with Philadelphia and St Louis representing the two ends of the spectrum.
In a study on the Spanish Flu, conducted in 2007, every city amongst the forty-three US cities that were analysed adopted at least one of the following three social restrictions, or lockdown measures: school closures, cancellation of public gatherings, and isolation and quarantine.
The cities that implemented all three lock down measures early and rigidly not only delayed the peak in the number of deaths, but also reduced size of the peak and the total number of deaths. There was also a direct association between increasing the number of days for which lockdown measures were implemented and reducing the total number of deaths. Meaning the longer the lockdown, the fewer people died from the Spanish Flu.
Looking in more detail at New York City, Pittsburgh, and Denver, we need to understand what is meant by total excess death rate, and public health response time.
Total mortality is expressed as total excess death rate (EDR) per 100 000 population, which means the smaller the number per 100 000 population, the fewer people that died.
Public Health Response Time (PHRT) reflects the time (in days) the city took to implement lockdown measures in relation to excess mortality occurring in the city. This figure can be a positive or negative number. If it is a positive number, the city implemented the lockdown measures after the death rate began to accelerate in the city. If the figure is negative, then the city implemented the lockdown measures early, before the weekly death rates began to accelerate.
New York City reacted quickly to the Spanish Flu pandemic by implementing sustained and rigidly applied compulsory isolation and quarantine methods, at the beginning of September, 1918, and included enforced staggered business hours, to avoid rush hour crowding, from October 5th 1918 till November 3rd 1918. Schools and theatres remained open in New York, though under strict regulations. Anti-spitting measures were also in place, through education as well as through misdemeanour fines.
During the period of the pandemic, New York City became known internationally for innovation with regards to mandatory case reporting, and for rigidly enforcing isolation and quarantine methods. Sick individuals were isolated in hospitals and makeshift facilities. And those that were exposed, but not showing symptoms, were quarantined in their homes with official placards declaring the site a quarantine location. With these early and sustained interventions, New York City experienced the lowest total excess death rate on the east coast over the 24-week analysis period, as is reflected in the 452 deaths per 100 000 population.
New York City’s Public Health Response Time was -11 days and the weekly Excess Death Rate was 0/100 000, when lockdown measures were implemented. Its first case was on the 5th of September and it implemented lockdown measures on the 18th of September (relatively early lockdown in relation to its first case and first flu death). It employed 73 days of lockdown measures (relatively long lockdown period) and the time to peak was 35 days (which is a relatively long delay in peaking) and the magnitude of the peak excess death rate was 90/100 000 (relatively low peak).
Data sourced from: Public Health Reports, Vol 45, No 39, September 26, 1930
In the middle of September, New York City made influenza and pneumonia reportable and resolved that an epidemic existed. The lockdown measures implemented from September through to November, caused the steep decline in mortality.
In Pittsburgh on the other hand, senior officials executed a public gathering ban on October 4th 1918 but their subordinates only implemented the ban on the 24th of October, around the time of school closures. Only a week later, did the city ban all public gatherings. Pittsburgh implemented its lockdown measures late and not all-at-once.
Pittsburgh’s total Excess Death Rate was 807/100 000 (higher than New York City) and achieved the worse mortality rates out of 43 US cities studied. The Public Health Response Time was +7 days, and the lockdown measures were implemented for only 53 days. A short lockdown compared to other cities.
The first case reported in Pittsburgh, was the 4th of September. The lockdown measures were implemented an entire month later, on the 4th of October. The time to peak was 32 days, only three days sooner than New York City, but produced a peak death rate much higher than New York City at 130/100 000.
From the first days of the ban, Pittsburgh city officials expressed ambivalence and hostility. They were reluctant to shut down the city’s economy and the apathy towards the longstanding health of its population, as depicted by the longstanding high coal-burning pollution levels in Pittsburgh, was reflected in the highest Spanish Flu per capita death rate in the nation.
Denver responded twice with extensive measures of lockdown measures, which included public gathering bans, school closures, isolation and quarantine including staggered business hours. This city’s first case was documented on the 17th of September and the date of the first lockdown measure was the 6th of October. Meaning Denver took a longer time to respond than New York City.
The Public Health Response Time was 9 days and the lockdown measures were applied for 151 days, double that of New York City, but these were not 151 consecutive days. The time to peak was 14 days (quicker than New York City) and the peak deaths were 55/100 000 (about half that of New York City), but the Total Excess Death Rate was 630/100 000 which was still greater than New York City. This confers that a quick lockdown saves lives, as was implemented in New York City.
During the recorded period Denver implemented lockdown, reversed the lockdown, and then implemented the lockdown again, and a two-peak mortality curve therefore developed. We can learn a lot from two-peak mortality curves in that when the lockdown measures are deactivated, deaths increase and when they are reactivated, then deaths decrease again. This confers that leaders should not end lockdowns too early.
While this further supports the need for lockdown measures as a critical component of the action plan to deal with a pandemic, there are a few additional lessons to be learnt. The death rate is inversely but directly related to the lockdown measures applied, meaning that the stricter the lockdown rules and the longer they are applied, the fewer the overall deaths from the pandemic.
Covid-19 - European Union vs United States
It’s not just with data from the Spanish Flu that we can see the value of lockdown measures. The implementation of strict lockdown strategies makes a difference in the spread of the Covid-19 disease as well. We can see this when we compare the average of new Covid-19 cases in the United States to the average of new cases in the European Union.