**As New Jersey begins reopening, we will be posting updates three times per week (M-W-F) at 9 a.m.**

 

KEY TAKEAWAYS (July 3, 2020)
  1. Recently, Harvard’s Global Health Institute released a set of core metrics to evaluate COVID response. Today we add a map of New Jersey using this classification system. Most of New Jersey is in the “yellow” range. According to the Global Health Institute, this means New Jersey can employ less intense control mechanisms. New Jersey has a lower rate of new cases than many states in the country.
  2. Across the state, the rates of new cases and new deaths are staying about the same, while the rates of new cases in the southern part of the state (the ‘slow’ region) are slightly higher than in the northern part of the state. Compared to earlier this week, the rates of new cases in Atlantic and Cumberland Counties, previously high, has dipped back below the 10 per 100,000 “quarantine threshold”. 

**Data like these are inherently noisy. Recently, the Johns Hopkins Coronavirus GitHub, where we get our data, has recorded “negative” increases in confirmed cases in some counties in New Jersey.  This likely reflects updates to database records in New Jersey. This could give a misleading impression about case counts. For counties with reports of “negative” new cases, we report the data as missing in the heat map. We smooth the data over a 7-day period to help account for the noise. In late June, the state began to include probable deaths as well as confirmed deaths in the numbers reported to the Johns Hopkins database.  This caused a large spike in the reported number of new deaths. We included these in the total deaths, but took the spike out of the incremental day analysis to avoid a misleading spike in the graph. Each date’s data point includes the average of data three days in the future and three days in the past. Please consider these daily plots as a useful rough sketch. State reports and detailed models provide additional information.

Contact Sarah Allred at srallred@camden.rutgers.edu

Regional Definitions (based on disease progression)

 
  • Northeast: Bergen, Essex, Hudson, Middlesex, Monmouth, Ocean, Passaic and Union counties (counties with >1000 cases on April 1).
  • Northwest: Hunterdon, Mercer, Morris, Somerset, Sussex and Warren counties.
  • South: Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester, Salem Counties.

**Note: the regional definitions are not the typical North/Central/South outlines and are based on disease progression throughout the state.**


Core metrics to evaluate COVID response

 
  • Harvard’s Global Health Institute released a set of core metrics to evaluate COVID response. This map of New Jersey uses this classification system. Most of New Jersey is in the “yellow” range. According to the Global Health Institute, this means New Jersey can employ less intense control mechanisms. New Jersey has a lower rate of new cases than many states in the country.

(Source: Harvard Global Health Institute and Harvard’s Edmond J. Safra Center for Ethics)


Where we are now: New Cases Each Day Per 100,000 Population

If the image doesn’t appear, click here.

WHAT IT MEANS
  • The density of new cases is now highest in the southern (‘slow’) region of the state.  The density of new cases is staying about the same in all parts of the state. 


Where we are now: New Deaths Each Day Per 100,000 Population

If the image doesn’t appear, click here.

 

WHAT IT MEANS
  • The density of new deaths is now about the same across the three regions of the state. The density of new deaths is staying about the same in all parts of the state.


County-Level Plots: new cases each day per 100,000 population

Atlantic County Gloucester County Ocean County
Bergen County Hudson County Passaic County
Burlington County Hunterdon County Salem County
Camden County Mercer County Somerset County
Cape May County Middlesex County Sussex County
Cumberland County Monmouth County Union County
Essex County Morris County Warren County

 

County-Level Plots: new deaths each day per 100,000 population

Atlantic County Gloucester County Ocean County
Bergen County Hudson County Passaic County
Burlington County Hunterdon County Salem County
Camden County Mercer County Somerset County
Cape May County Middlesex County Sussex County
Cumberland County Monmouth County Union County
Essex County Morris County Warren County

 


Technical notes: 
  1. Data are downloaded from JHU Github approximately 7 a.m. each day. JHU Github sometimes lags New Jersey Department of Health Dashboard.
  2. Day 10 (March 31, 2020) of the JHU Github appeared to contain incorrect data for deaths. We averaged days 9 and 11 to get day 10. Day 31 also contained incorrect data, so we performed a similar averaging procedure. On day 36, Hudson County reported a lower number of total deaths than on day 35. To avoid “negative deaths”, we adjusted the death estimates for the previous days.
  3. Population estimates are from the 2010 Census.
 
Methods: 

The plots here visualize the progress of COVID-19 across three regions in New Jersey. New cases (first figure) and new deaths (second figure) are shown on the y-axis, and time (in days) is shown on the x-axis. To account for population differences between the three regions, we plot the number of new cases (or deaths) per 100,000 population. For example, if the value on the y-axis is 10, that would mean that 10 out of every 100,000 people tested positive for COVID-19 the previous day. The first day on the graph is March 22, 2020.

We plot a rolling 7-day average of the data. This means that each days number is an average of 7 days. We do this because there are variations in the time it takes to report deaths. For example, a health department might be overwhelmed and unable to enter all the deaths on one day, making the numbers look lower than they should.

In addition to plotting data by county, we also average across three regions of the state. The first is northeastern counties. These are counties that had more than 1000 infections each on 4/1/2020, and include Bergen, Essex, Hudson, Middlesex, Monmouth, Ocean, Passaic and Union counties. The second is northwestern counties. These all had fewer than 1000 infections on 4/1/2020. The third is southern counties, including Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester, and Salem counties. These counties had fewer than 250 cases on 4/1/2020.