Analyzing Spatial Clustering and the Spatiotemporal Nature and Trends of HIV/AIDS Prevalence using GIS: The Case of Malawi, 1994-2010

bmcidBMC Infectious Diseases 2014, 14:285, Published online 23 May 2014

By Leo C Zulu, Ezekiel Kalipeni, and Eliza Johannes

Although local spatiotemporal analysis can improve understanding of geographic variation of the HIV epidemic, its drivers, and the search for targeted interventions, it is limited in sub-Saharan Africa. Despite recent declines, Malawi’s estimated 10.0% HIV prevalence (2011) remained among the highest globally. Using data on pregnant women in Malawi, this study 1) examines spatiotemporal trends in HIV prevalence 1994-2010, and 2) for 2010, identifies and maps the spatial variation/clustering of factors associated with HIV prevalence at district level.

Inverse distance weighting was used within ArcGIS Geographic Information Systems (GIS) software to generate continuous surfaces of HIV prevalence from point data (1994, 1996, 1999, 2001, 2003, 2005, 2007, and 2010) obtained from surveillance antenatal clinics. From the surfaces prevalence estimates were extracted at district level and the results mapped nationally. Spatial dependency (autocorrelation) and clustering of HIV prevalence were also analyzed. Correlation and multiple regression analyses were used to identify factors associated with HIV prevalence for 2010 and their spatial variation/clustering mapped and compared to HIV clustering.


Analysis revealed wide spatial variation in HIV prevalence at regional, urban/rural, district and sub-district levels. However, prevalence was spatially leveling out within and across ‘sub-epidemics’ while declining significantly after 1999. Prevalence exhibited statistically significant spatial dependence nationally following initial (1995-1999) localized, patchy low/high patterns as the epidemic spread rapidly. Locally, HIV “hotspots” clustered among eleven southern districts/cities while a “coldspot” captured configurations of six central region districts. Preliminary multiple regression of 2010 HIV prevalence produced a model with four significant explanatory factors (adjusted R2 = 0.688): mean distance to main roads, mean travel time to nearest transport, percentage that had taken an HIV test ever, and percentage attaining a senior primary education. Spatial clustering linked some factors to particular subsets of high HIV-prevalence districts.

Spatial analysis enhanced understanding of local spatiotemporal variation in HIV prevalence, possible underlying factors, and potential for differentiated spatial targeting of interventions. Findings suggest that intervention strategies should also emphasize improved access to health/HIV services, basic education, and syphilis management, particularly in rural hotspot districts, as further research is done on drivers at finer scale.”

Read the paper [PDF]

Geospatial Technology Speeds Analysis for US Army

Ready-to-Use Templates Quickly Deliver Critical Information to the Field

Esri has provided a recently revised set of customized templates to the US Army for its Distributed Common Ground System-Army (DCGS-A). These easy-to-use templates come with maps, analytic capabilities, and other visualization tools, as well as a simple information model for creating geospatial products.

The templates will help geospatial engineers, intelligence analysts, and geospatial intelligence (GEOINT) imagery analysts using DCGS-A to rapidly make products to support requests from commanders for operations around the world. DCGS-A is the US Army’s main system for processing and posting data; providing mapping and weather information; and sharing intelligence, surveillance, and reconnaissance (ISR) information with army units.

“Esri technology, such as the templates, gives the army an easy-to-use, technical advantage that helps soldiers optimize GEOINT capability resident in DCGS-A,” said Colonel Ed Riehle, the US Army Training and Doctrine Command’s Capability Manager for Sensor Processing.

“Esri is pleased to have partnered closely with the staff who work with the DCGS-A to deliver these important and innovative templates and tools for the US Army,” said Esri president Jack Dangermond. “We designed them so the analysts can be more productive in what is a very fast-paced operational tempo. We also believe that by adopting these tools, the value of the US Army’s investment in Esri technology will be maximized.”

The templates were customized to match the DCGS-A workflows. Esri staff worked with analysts and specialists at the US Army Intelligence Center of Excellence at Fort Huachuca, Arizona, to refine the template requirements.

These new resources will help analysts do everything from creating sketches of military compounds to making maps that show safe and suitable areas for landing helicopters. The revised templates include

  • Incident analysis to map improvised explosive device (IED) incidents or other significant events.
  • Cross-country mobility analysis to identify key terrain and sketch approach routes.
  • Intervisibility analysis to identify areas of cover and concealment.

The templates will be available on a variety of army websites including the DCGS-A Portal and the Intelligence Knowledge Network as well as in ArcGIS for the Military—Land Operations, an Esri product optimized to provide an interoperable platform to manage, visualize, analyze, and share geospatial information for land-based missions.

Esri will demonstrate ArcGIS for the Military—Land Operations at the GEOINT Symposium April 14–17, in Tampa, Florida, in booth #5036.

To learn more about ArcGIS for the Military—Land Operations templates and other resources, visit

[Source: Esri press release]

OGC Encourages Attendance at AGILE and COBWEB Workshop – “Citizen Science, Quality and Standards”

OGC_Logo_Border_Blue_3DAGILE (Association of Geographic Information Laboratories for Europe) and COBWEB (Citizen OBservatory WEB, an EU FP7 Project) invite public participation in a special workshop on crowdsourced data and the environment.  The AGILE & COBWEB Workshop – “Citizen Science, Quality and Standards” will be held June 3, 2014 in Castellón, Spain in conjunction with the AGILE 2014 conference.

Crowdsourced data (“people as sensors” recording real-time observations and measurements) are a valuable source of scientific and policy-making information when enhanced with an indication of quality and fused with authoritative data. This workshop seeks to engage the scientific community in discussions about the use of quality controlled crowdsourced environmental data.

The infrastructure being developed within COBWEB exploits technological developments in ubiquitous mobile devices. It also exploits and contributes to developments in the operational standards that are used widely in public spatial data infrastructures and also increasingly used in science. COBWEB infrastructure is being designed to enable citizens living within Biosphere Reserves to collect environmental information on a range of parameters including species distribution, flooding and land cover/use. The main driver is the value that can result when citizens participate in environmental governance. It is anticipated that COBWEB work products will be useful in similar activities around the world.

To maximize impact, COBWEB is working with standards organizations. Specifically, COBWEB will aim to improve the usability of OGC Sensor Web Enablement standards and the OGC GeoPackage Encoding Standard with mobile devices, develop widespread acceptance of the data quality approach developed and maximize the applications potential of COBWEB outputs.

Details, agenda and call for brief presentations are available at:

COBWEB organizers:

  • Stephanie Ties, Environment Systems
  • Bart De Lathouwer, OGC Europe (OGCE)
  • Mike Jackson, University of Nottingham, 
  • Lars Bernard, TU Dresden
  • Mason Davis, Welsh Government

About OGC: The OGC® is an international consortium of more than 475 companies, government agencies, research organizations, and universities participating in a consensus process to develop publicly available geospatial standards. OGC standards support interoperable solutions that “geo-enable” the Web, wireless and location-based services, and mainstream IT. Visit the OGC website at

[Source: OGC press release]

Understanding and Managing Our Oceans: Esri Ocean GIS Forum, 05-07 November 2014

Esri logoSee different ways that ocean and maritime agencies are successfully using geospatial analysis to better understand the ocean’s dynamic environment and make intelligent decisions. The Esri Ocean GIS Forum is your opportunity to explore new GIS technology.

Ocean scientists, hydrographers, and GIS experts will be addressing topics that are particularly relevant to people who work for research institutions, the National Oceanic and Atmospheric Administration, seafood companies, energy providers, local and state governments, port authorities, shipping companies, the US Coast Guard, and the US Navy.

The Esri Ocean GIS Forum is a unique event that offers these activities:

  • A rigorous agenda of session topics presented by GIS users that work in the ocean and maritime industries
  • Best practice presentations by project managers from ocean agencies
  • An ocean science forum to share and exchange ideas
  • ArcGIS and ArcGIS Online technical demonstrations set in an ocean and maritime context
  • Meet-and-greet opportunities for expanding professional networks
  • On-site GIS professionals and domain experts that can answer questions and offer advice
  • An EXPO sponsored by ocean and maritime business consultants and technology providers
  • An app contest for posters and Story Maps
  • Two GIS hands-on workshops
  • Learning Lab

Immerse yourself in all things GIS at the Esri Ocean GIS Forum.

GEOFIM: A WebGIS Application for Integrated Geophysical Modelling in Active Volcanic Regions

Computers & GeosciencesComputers & Geosciences, Accepted 02 May 2014

By Gilda Currenti, Rosalba Napoli, Antonino Sicali, Filippo Greco, and Ciro Del Negro

“We present GEOFIM (GEOphysical Forward/Inverse Modeling), a WebGIS application for integrated interpretation of multiparametric geophysical observations. It has been developed to jointly interpret scalar and vector magnetic data, gravity data, as well as geodetic data, from GPS, tiltmeter, strainmeter and InSAR observations, recorded in active volcanic areas. GEOFIM gathers a library of analytical solutions, which provides an estimate of the geophysical signals due to perturbations in the thermal and stress state of the volcano. The integrated geophysical modeling can be performed by a simple trial and errors forward modeling or by an inversion procedure based on NSGA-II algorithm. The software capability was tested on the multiparametric data set recorded during the 2008-2009 Etna flank eruption onset. The results encourage to exploit this approach to develop a near-real-time warning system for a quantitative model-based assessment of geophysical observations in areas where different parameters are routinely monitored.”

Photos: ArcNews Editor Tom Miller’s Retirement

Yesterday, long-time ArcNews editor and my friend Tom Miller retired.

He leaves a monumental legacy: 79 issues of a magazine that today reaches about a million people each quarter.

In a time when many people pass their lives by simply checking boxes and plodding through life, Tom was a true creator.  Whether putting together an issue of ArcNews or writing another book, Tom was–is–a master at taking a random assortment of half-baked ideas and rough drafts and nurturing them and growing them into documents that have meaning.

Jack Dangermond had some very kind words for Tom during his farewell lunch yesterday.  He praised Tom for his editing skills, but more importantly for the enormous impact his creations have had on the GIS community.

Tom's retirement lunch in the "Zen Room" in the Esri Cafe'.

Tom’s retirement lunch in the “Zen Room” in the Esri Cafe’.


Bill Derrenbacher, Esri’s director of professional services, chatting with Dr. Dawn Wright, Esri’s chief scientist.


Tammy Johnson, who designed many of Tom’s 79 issues of ArcNews; Monica Pratt, ArcUser editor and Publication Team Lead; and the man of the hour, Tom Miller.


Tom’s wife Jayne chatting with Pete Schreiber, Esri legal counsel.


Let’s eat!


After lunch, many friends and co-workers gathered for Tom’s retirement cake. The tables were covered with enlarged copies of ArcNews issues he created over the years.


ArcUser editor and Publication Team Lead Monica Pratt sharing some stories about Tom.


Karen Hurlbut, who was editor of ArcNews before Tom took over some 20 years ago, shares some stories.


Enough talking! Cut the cake!


Tom with his “card”–a custom issue of ArcNews with tongue-in-cheek articles, such as the one pasted below.


Nobel Prize for Literature Awarded to ArcNews Editor

The 2014 Nobel Prize for Literature was awarded to Thos. Kent Miller, editor of Esri’s ArcNews quarterly tabloid newspaper, for the issue titled “Spring 2014”.

While it is unusual for an editor of a newspaper to receive this prestigious honor, Dr. Borgus Jerkenhammer, Permanent Secretary of the Swedish Academy and assistant to the director of the Nobel Prize for Literature Search Committee and Curling Team, noted that “Miller’s reoccurring story of the power and benefits of geospatial technology across different organizations and industries gives hope to a hopeless world.  And that article about Roger Tomlinson had me in tears from ‘It is with great sadness…’.”

Nobody was more surprised with the award than Miller himself.  “When they called and told me I had received the 2014 Nobel Prize for Literature, I assumed it was because of my latest masterwork of H. Rider Haggard/Great Detective pastiche, Allan Quatermain at the Dawn of Time, which is now available on,” Miller said.  “When they said the award was for ArcNews, I though, wait, this must be a crank phone call.  I mean, ArcNews?  Really?”

Miller plans to use part of the $1.2 million in prize money to finally fix the heater in his Jacuzzi.  “Editing ArcNews is a very physically demanding job, and by the end of the issue my body feels like it’s been hit by a truck,” notes Miller.  “It will be nice to have that damn Jacuzzi working again.”

Enjoy your retirement, Tom–you certainly deserve it!

And I’ll leave everyone with this:

“Tom, you have left very big shoes to fill,” said Jack Dangermond.  “By the way, what size shoes do you wear?”


GeoPlanner for ArcGIS Enables Resilient Design

Create and Share Plans Easily with Esri Geodesign Application

Esri recently released a web app called GeoPlanner for ArcGISthat brings the power of geodesign to land-based planning. GeoPlanner for ArcGIS is a JavaScript-based application that requires no plug-ins and has been designed to run in web browsers on both desktop and standard-sized tablet devices supporting a minimum 1024 x 768 resolution.

GeoPlanner for ArcGISincorporates each aspect of a complete planning workflow—project creation, data identification, comparative analysis, and reporting—into a single web-based application. The app helps planners from a wide range of industries create and report on alternative planning scenarios to make geographically informed decisions.

Create, analyze, and report on alternative planning scenarios using the new GeoPlanner for ArcGIS app.

Create, analyze, and report on alternative planning scenarios using the new GeoPlanner for ArcGIS app.

GeoPlanner for ArcGIS comes with several ready-to-use planning templates for land-use planning, special event planning, and more, and it can be easily configured using ArcGIS for Desktop to meet the needs of your specific industry or organization.

You can purchase the GeoPlanner for ArcGIS app from ArcGIS Marketplace. You will need an ArcGIS Online subscription or a trial account to start using the app.

People outside the United States should contact Esri Offices in their area.

[Source: Esri press release]