Epidemics begin in one of three model independent ways.
- Exponential (Incidence accelerates rapidly)
- 1918 Influenza (San Francisco, 1918)
- Plague (Bombay, 1905)
- Smallpox (Khuina, Iran, 1977)
- Power (Incidence increases day by day)
- Measles (London, 1948)
- HIV/AIDS (New York City, 1982 – 2002)
- Linear (Incidence remains constant)
- Heart Disease
COVID-19 in Mississippi has grown persistently.
Cases and deaths have both grown persistently since March 11, 2020. (Data are the daily reports given by MSDH.)
Deaths lagged by 5 days - the latency between COVID-19's first symptoms and death.
The Stay-in-Place proclamation(yellow marker) arrested the exponential growth of the cases as announced daily, leaving a quadratic growth phase (the darker red dotted trendline) until the relaxation of the Stay-at-Home orders (green marker). Since that time, there has been a fairly steady report of 275 cases a day (the lighter data points and trendline).
Deaths have continued to grow quadratically.
This dichotomy between case reports and deaths is explored in the next tab.
Two distinct COVID-19 epidemics have existed side-by-side: Community and Long Term Care Facility Residents'.
Deaths in the community have grown linearly with time, 5 deaths a day since the Stay-in-Place order (yellow dot). Case determinations have been predominantly community-based, hence the linear pattern seen in the previous tab.
LTCF deaths have accelerated up to a much faster rate - after a short delay. Since the start of the relaxation of Stay-in-Place restrictions (green dot), 8 LTCF residents have died each day, on average.
(Red dots plot the Community COVID-19 deaths, according to the date on the death certificate; the brown are the LTCF Resident deaths. The most recent data points are incomplete counts - the recording of death certificates takes a little time. )
The cumulative number of COVID-19 deaths grew exponentially for the first few days of the Mississippi epidemic, just as in New York City. This threat cannot be understated. Such an initial growth rate would point to 24 deaths a day on April 1, ∼10,000 deaths a day by May and millions a day shortly thereafter.
The mortality rate was arrested at 5/day when Stay-in-Place was ordered (left graph), causing deaths to accumulate linearly (right graph). These orders have had a lasting effect that has outlived subsequent orders (starting at the green dot) relaxing social distancing.
The per-capita number of community based COVID-19 Deaths is 12 per 100,000 thus far, which is near the median figure for the United States. This is less than a tenth of New York, so it is not surprising that few people in Mississippi know acquaintances who have contracted the virus.
- the last two or three days of data are very incomplete.
- it does take time to finally register all the deaths - up to two weeks.
- so the meaning of any small trend is uncertain.
Deaths of residents of Long Term Care Facilities now exceed half the Mississippi COVID-19 deaths.
The first LTCF death was March 21, 2020. Deaths grew as a cubic function of time, and so have caught up - and surpassed - the number of community deaths.
The daily log of LTCF deaths (per death certificates) grows linearly. The smaller numbers in the last few days reflect the lag in registering death certificates.