Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2005 Mar;99(3):218-25.
doi: 10.1016/j.trstmh.2004.06.010.

The household distribution of trachoma in a Tanzanian village: an application of GIS to the study of trachoma

S R Polack  1 , A W Solomon, N D E Alexander, P A Massae, S Safari, J F Shao, A Foster, D C Mabey
Affiliations

The household distribution of trachoma in a Tanzanian village: an application of GIS to the study of trachoma

S R Polack et al. Trans R Soc Trop Med Hyg. 2005 Mar.

Abstract

The distribution of active trachoma in Kahe Mpya, Tanzania, an endemic village of approximately 1000 people, was mapped spatially and analysed for associated risk factors and evidence of clustering. An association between distance to water source and active disease was demonstrated, although this was reduced after accounting for the lack of independence between cases in the same household. Significant clustering of active trachoma within households was demonstrated, adding support to the hypothesized importance of intra-familial transmission. The spatial distribution of trachoma was analysed using the spatial scan statistic, and evidence of clustering of active trachoma cases detected. Understanding the distribution of the disease has implications for understanding the dynamics of transmission and therefore appropriate control activities. The demonstrated spatial clustering suggests inter-familial as well as intra-familial transmission of infection may be common in this setting. The association between active trachoma and geographical information system (GIS) measured distance to water may be relevant for planning control measures.

PubMed Disclaimer

Conflict of interest statement

Conflicts of interest statement.

The authors have no conflicts of interest concerning the work reported in this paper.

Figures

Figure 1
Figure 1
Spatial clustering of active trachoma in Kahe Mpya – the number of cases out of total number of people per household with the location of significant clusters of active trachoma as identified by the spatial scan statistic.
Figure 2
Figure 2
Prevalence of active trachoma by GIS-determined walking time to the sub-village water source.
Figure 3
Figure 3
The distribution of cases of active trachoma by bedroom in Kahe Mpya - the location of bedrooms within households with active trachoma
See this image and copyright information in PMC

References

    1. Bailey R, Osmond C, et al. Analysis of the household distribution of trachoma in a Gambian village using a Monte Carlo simulation procedure. Int J Epidemiol. 1989;18(4):944–51. - PubMed
    1. Ballard RC, Fehler HG, et al. The epidemiology and geographical distribution of trachoma in Lebowa. S Afr Med J. 1981;60(14):531–5. - PubMed
    1. Cairncross S, Feachem R. Environmental health engineering in the tropics. 2nd ed. London: John Wiley & Sons; 1993.
    1. Cairncross S. Trachoma and water. Community Eye Health. 1999;12(32):58–59. - PMC - PubMed
    1. Courtright P, Sheppard J, et al. Latrine ownership as a protective factor in inflammatory trachoma in Egypt. Br J Ophthalmol. 1991;75(6):322–5. - PMC - PubMed

Publication types

MeSH terms