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. 2005 Nov;168(4):701-722.
doi: 10.1111/j.1467-985X.2005.00372.x.

The spatial structure of epidemic emergence: geographical aspects of poliomyelitis in north-eastern USA, July-October 1916

Barry Trevelyan  1 , Matthew Smallman-Raynor, Andrew D Cliff
Affiliations

The spatial structure of epidemic emergence: geographical aspects of poliomyelitis in north-eastern USA, July-October 1916

Barry Trevelyan et al. J R Stat Soc Ser A Stat Soc. 2005 Nov.

Abstract

The great epidemic of poliomyelitis which swept New York City and surrounding territory in the summer of 1916 eclipsed all previous global experience of the disease. We draw on epidemiological information that is included in the seminal US Public Health Bulletin 91, 'Epidemiologic studies of poliomyelitis in New York City and the northeastern United States during the year 1916' (Washington DC, 1918), to re-examine the spatial structure of the epidemic. For the main phase of transmission of the epidemic, July-October 1916, it is shown that the maximum concentration of activity of poliomyelitis occurred within a 128-km radius of New York City. Although the integrity of the poliomyelitis cluster was maintained up to approximately 500 km from the metropolitan focus, the level and rate of propagation of disease declined with distance from the origin of the epidemic. Finally, it is shown that the geographical transmission of the epidemic in north-eastern USA probably followed a process of mixed contagious-hierarchical diffusion.

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Figures

Fig. 1
Fig. 1
Monthly rate of notifications of poliomyelitis (per 100 000 population) in the USA, July 1910–December 1971: the date of introduction of inactivated poliovirus vaccine (IPV) is indicated (source: series constructed from state level notifications included in the Public Health Reports (Washington DC: Government Printing Office, 1910–1951) and Morbidity and Mortality Weekly Report (Atlanta: Centers for Disease Control, 1952–1972))
Fig. 2
Fig. 2
Poliomyelitis in north-eastern USA, July–October 1916: weekly count of notifications of poliomyelitis in New York City (■) and other localities (□), and mean distance from Brooklyn of newly notified cases of poliomyelitis plotted by week (——)
Fig. 3
Fig. 3
Notification rates of poliomyelitis (per 100 000 population) by county for sample states of north-eastern USA, 1916: annuli, set at 128 km, 230 km and 500 km from Brooklyn, are plotted for reference; the annulus at 230 km is based on Fig. 4 and marks the break point in a segmented regression analysis of county level notification rates of poliomyelitis against distance from New York City; the annuli at 128 km and 500 km are based on the spatial association analysis in Fig. 5 and delimit the area within which the maximum spatial concentration of high rates of poliomyelitis occurred (128 km) and the maximum limit of the spatial cluster of poliomyelitis around New York City (500 km) (note that the state of Pennsylvania has been omitted from the analysis on account of missing information; source, drawn from information in Lavinder et al. (1918), Tables U–DD, pages 243–251, and map BB, opposite page 287)
Fig. 4
Fig. 4
Poliomyelitis case rate (per 100 000 population) against distance from Brooklyn for 148 counties of north-eastern USA, July–October 1916: a segmented ordinary least squares regression model (with two straight line segments), defined in equation (1), was fitted at each possible division of the 148 data points;——, division which minimized the residual sum of squares
Fig. 5
Fig. 5
Spatial association of activity of poliomyelitis in north-eastern USA, July–October 1916: •, value of the Gi(d) statistic, as a standard normal deviate, for a series of distances from Brooklyn (distances are defined by the positions of 148 counties of north-eastern USA); •, poliomyelitis case rate (per 100000 population) for counties against their distance from Brooklyn; – – –, z = 1.65 line, marking the nominal significance of Gi(d) at the p = 0.05 level in a one-tailed test for the spatial association of high values
Fig. 6
Fig. 6
Contour plot of the value of the Gi(d) statistic, as a standard normal deviate, by week and by distance from Brooklyn: darker shading categories indicate greater values of Gi(d); the horizontal axis has been formed by ranking the 148 counties in terms of their straight line distance from Brooklyn; absolute distances (in kilometres) are given; beginning at the upper left-hand sector of the plot, values of the Gi(d) statistic display a tendency to reduce with spatial (horizontal axis) and temporal (vertical axis) distance from New York City
Fig. 7
Fig. 7
Diffusion of poliomyelitis in 148 counties of north-eastern USA, July–October 1916: (a) relationship between time to first appearance of poliomyelitis (ti) and distance to Brooklyn (di); (b) relationship between time to first appearance of poliomyelitis (ti) and population size (Pi) (note that ti and Pi have been logarithmically transformed; ———, linear trend lines fitted by ordinary least squares)
Fig. 8
Fig. 8
Processes of poliomyelitis diffusion in north-eastern USA, July–October 1916: the line traces plot weekly values of the spatial autocorrelation statistic, Moran's I, as a standard normal deviate for three hypothetical diffusion processes, contagious diffusion (——, nearest neighbour graph), mixed contagious–hierarchical diffusion (— —, nearest larger neighbour graph) and hierarchical diffusion (- - - - -, population hierarchy graph); ■, weekly notification rates of poliomyelitis (per 100000 population);——, z = 1.65 line, marking the nominal p = 0.5 level in a one-tailed test for positive spatial autocorrelation
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References

    1. Assunção RM, Reis EA. A new proposal to adjust Moran's I for population density. Statist. Med. 1999;18:2147–2162. - PubMed
    1. Christie AB. Infectious Diseases: Epidemiology and Clinical Practice. 4th edn. Vol. 2. Churchill Livingstone; Edinburgh: 1987.
    1. Cliff AD, Haggett P. Atlas of Disease Distributions: Analytic Approaches to Epidemiological Data. Blackwell; Oxford: 1988a.
    1. Cliff AD, Haggett P. Methods for the measurement of epidemic velocity from time-series data. Int. J. Epidem. 1988b;11:82–89. - PubMed
    1. Cliff AD, Haggett P, Ord JK. Spatial Aspects of Influenza Epidemics. Pion; London: 1986.

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