New publication! Snakebite victim profiles and treatment-seeking behaviors in two regions of Kenya: results from a health demographic surveillance system in Tropical Medicine and Health (BMC)
Permanent injury from a puff adder bite, Kenya, 2016
Back in 2016 or so, I nearly stepped on a headless and very dead spitting cobra on an island in Homa Bay, Kenya. The locals apparently weren’t satisfied with simply decapitating it, but smashed the head to bits presumably so it couldn’t come back to life and bite someone. That gave me a hair brained idea to do a research project on snakebites and I’m proud to say that the results of that work have been published today.
This work was a team effort under the auspices of the Nagasaki University Institute of Tropical Medicine. It couldn’t have happened without the incredible contributions of researchers, students and local partners,in Kenya, Japan and the United States.
Snakebites are a major cause of permanent injury and death among poor, rural populations in developing countries, including those in East Africa. This research characterizes snakebite incidence, risk factors, and subsequent health-seeking behaviors in two regions of Kenya using a mixed methods approach.
As a part of regular activities of a health demographic surveillance system, household-level survey on snakebite incidence was conducted in two areas of Kenya: Kwale along the Kenyan Coast and Mbita on Lake Victoria. If someone in the home was reported to have been bitten in the 5 years previous to the visit, a survey instrument was administered. The survey gathered contextual information on the bite, treatment-seeking behavior and clinical manifestations. To obtain deeper, contextual information, respondents were also asked to narrate the bite incident, subsequent behavior and outcomes.
8775 and 9206 households were surveyed in Kwale and Mbita, respectively. Out of these, 453 (5.17%) and 92 (1.00%) households reported that at least one person had been bitten by a snake in the past 5 years. Deaths from snakebites were rare (4.04%), but patterns of treatment seeking varied. Treatment at formal care facilities were sought for 50.8% and at traditional healers for 53.3%. 18.4% sought treatment from both sources. Victims who delayed receiving treatment from a formal facility were more likely to have consulted a traditional healer (OR 8.8995% CI [3.83, 20.64]). Delays in treatment seeking were associated with significantly increased odds of having a severe outcome, including death, paralysis or loss of consciousness (OR 3.47 95% CI [1.56; 7.70]).
Snakebite incidence and outcomes vary by region in Kenya, and treatment-seeking behaviors are complex. Work needs to be done to better characterize the spatial distribution of snakebite incidence in Kenya and efforts need to be made to ensure that victims have sufficient access to effective treatments to prevent death and serious injury.”
New publication: Ambient air pollution and non-communicable respiratory illness in sub-Saharan Africa: a systematic review of the literature
New publication from our Air Pollution and Health team out today in BMC Environmental Health:
Aerosol pollutants are known to raise the risk of development of non-communicable respiratory diseases (NCRDs) such as asthma, chronic bronchitis, chronic obstructive pulmonary disease, and allergic rhinitis. Sub-Saharan Africa’s rapid pace of urbanization, economic expansion, and population growth raise concerns of increasing incidence of NCRDs. This research characterizes the state of research on pollution and NCRDs in the 46 countries of Sub-Saharan Africa (SSA). This research systematically reviewed the literature on studies of asthma; chronic bronchitis; allergic rhinitis; and air pollutants such as particulate matter, ozone, NOx, and sulfuric oxide.
We searched three major databases (PubMed, Web of Science, and Scopus) using the key words “asthma”, “chronic bronchitis”, “allergic rhinitis”, and “COPD” with “carbon monoxide (CO)”, “sulfuric oxide (SO)”, “ozone (O3)”, “nitrogen dioxide (NO2)”, and “particulate matter (PM)”, restricting the search to the 46 countries that comprise SSA. Only papers published in scholarly journals with a defined health outcome in individuals and which tested associations with explicitly measured or modelled air exposures were considered for inclusion. All candidate papers were entered into a database for review.
We found a total of 362 unique research papers in the initial search of the three databases. Among these, 14 met the inclusion criteria. These papers comprised studies from just five countries. Nine papers were from South Africa; two from Malawi; and one each from Ghana, Namibia, and Nigeria. Most studies were cross-sectional. Exposures to ambient air pollutants were measured using spectrometry and chromatography. Some studies created composite measures of air pollution using a range of data layers. NCRD outcomes were measured by self-reported health status and measures of lung function (spirometry). Populations of interest were primarily schoolchildren, though a few studies focused on secondary school students and adults.
The paucity of research on NCRDs and ambient air pollutant exposures is pronounced within the African continent. While capacity to measure air quality in SSA is high, studies targeting NCRDs should work to draw attention to questions of outdoor air pollution and health. As the climate changes and SSA economies expand and countries urbanize, these questions will become increasingly important.”
New publication: “Long-Term PM2.5 Exposure Is Associated with Symptoms of Acute Respiratory Infections among Children under Five Years of Age in Kenya, 2014”
In early December, I was asked to submit a paper to a special issue on “Air pollution and health in Africa and the African Diaspora” which is great! But the deadline was Dec 31st, which is absolutely crazy. I pulled an amazing team together and somehow we made the deadline and now, here we are…. published!
Here’s the “video abstract.”
Introduction: Short-term exposures to air pollutants such as particulate matter (PM) have been associated with increased risk for symptoms of acute respiratory infections (ARIs). Less well understood is how long-term exposures to fine PM (PM2.5 ) might increase risk of ARIs and their symptoms. This research uses georeferenced Demographic Health Survey (DHS) data from Kenya (2014) along with a remote sensing based raster of PM2.5 concentrations to test associations between PM2.5 exposure and ARI symptoms in children for up to 12 monthly lags. Methods: Predicted PM2.5 concentrations were extracted from raster of monthly averages for latitude/longitude locations of survey clusters. These data and other environmental and demographic data were used in a logistic regression model of ARI symptoms within a distributed lag nonlinear modeling framework (DLNM) to test lag associations of PM2.5 exposure with binary presence/absence of ARI symptoms in the previous two weeks. Results: Out of 7036 children under five for whom data were available, 46.8% reported ARI symptoms in the previous two weeks. Exposure to PM2.5 within the same month and as an average for the previous 12 months was 18.31 and 22.1 µg/m3, respectively, far in excess of guidelines set by the World Health Organization. One-year average PM2.5 exposure was higher for children who experienced ARI symptoms compared with children who did not (22.4 vs. 21.8 µg/m3, p < 0.0001.) Logistic regression models using the DLNM framework indicated that while PM exposure was not significantly associated with ARI symptoms for early lags, exposure to high concentrations of PM2.5 (90th percentile) was associated with elevated odds for ARI symptoms along a gradient of lag exposure time even when controlling for age, sex, types of cooking fuels, and precipitation. Conclusions: Long-term exposure to high concentrations of PM2.5 may increase risk for acute respiratory problems in small children. However, more work should be carried out to increase capacity to accurately measure air pollutants in emerging economies such as Kenya.
New publication: Environmental and Household-Based Spatial Risks for Tungiasis in an Endemic Area of Coastal Kenya
New publication! I started working on this cool project on tungiasis (jiggers) with colleagues in Kenya and Japan way back in 2014. Today, I am happy to say that after much ado our work has finally seen the light of day, thanks to Nagasaki PhD student (and soon to be Dr.) Ayako Hyuga. It appears today in the journal Tropical Medicine and Infectious Disease (MDPI).
Environmental and Household-Based Spatial Risks for Tungiasis in an Endemic Area of Coastal Kenya
“#Tungiasis is a #cutaneous #parasitosis caused by an embedded female sand flea. The distribution of cases can be spatially heterogeneous even in areas with similar risk profiles. This study assesses household and remotely sensed environmental factors that contribute to the geographic distribution of tungiasis cases in a rural area along the Southern Kenyan Coast. Data on household tungiasis case status, demographic and socioeconomic information, and geographic locations were recorded during regular survey activities of the Health and Demographic Surveillance System, mainly during 2011. Data were joined with other spatial data sources using latitude/longitude coordinates. Generalized additive models were used to predict and visualize spatial risks for tungiasis. The household-level prevalence of tungiasis was 3.4% (272/7925). There was a 1.1% (461/41,135) prevalence of infection among all participants. A significant spatial variability was observed in the unadjusted model (p-value < 0.001). The number of children per household, earthen floor, organic roof, elevation, aluminum content in the soil, and distance to the nearest animal reserve attenuated the odds ratios and partially explained the spatial variation of tungiasis. Spatial heterogeneity in tungiasis risk remained even after a factor adjustment. This suggests that there are possible unmeasured factors associated with the complex ecology of sand fleas that may contribute to the disease’s uneven distribution.” #environmental #kenya #NTD #NeglectedTropicalDisease #parasitology #globalhealth #publichealth
New publication: An urban-to-rural continuum of malaria risk: new analytic approaches characterize patterns in Malawi
12 years in the making! Our new paper from partners at the University of Michigan and the #Malawi College of Medicine on new approaches to defining urban and rural environments in the context of malaria risk is now out in #Malaria Journal.
It was the last chapter in my dissertation to be published (all the rest were published when I was still in grad school.)Short version: malaria is complicated and really local. Malaria transmits poorly in urban and environments and well in rural environments. There’s urban like spaces in “rural” areas and rural-like spaces in “urban” areas, demanding a more nuanced view of what those terms really mean.
We know that malaria is a “rural” problem, but not all “rural” spaces are the same. Even in the country, there are “urban like” spaces and in “rural like” spaces even in the largest cities in Sub-Saharan Africa. Could those spaces impact malaria risk? If so, shouldn’t we redefine what we mean by urban vs. rural to inform intervention strategies to better target resources?
Here, we combine GIS and statistical methods with a house to house malaria survey in Malawi to create and test a new composite index of urbanicity and apply that to create a more nuanced risk map.
The urban–rural designation has been an important risk factor in infectious disease epidemiology. Many studies rely on a politically determined dichotomization of rural versus urban spaces, which fails to capture the complex mosaic of infrastructural, social and environmental factors driving risk. Such evaluation is especially important for Plasmodium transmission and malaria disease. To improve targeting of anti-malarial interventions, a continuous composite measure of urbanicity using spatially-referenced data was developed to evaluate household-level malaria risk from a house-to-house survey of children in Malawi.
Children from 7564 households from 8 districts in Malawi were tested for presence of Plasmodium parasites through finger-prick blood sampling and slide microscopy. A survey questionnaire was administered and latitude and longitude coordinates were recorded for each household. Distances from households to features associated with high and low levels of development (health facilities, roads, rivers, lakes) and population density were used to produce a principal component analysis (PCA)-based composite measure for all centroid locations of a fine geo-spatial grid covering Malawi. Regression methods were used to test associations of the urbanicity measure against Plasmodium infection status and to predict parasitaemia risk for all locations in Malawi.
Infection probability declined with increasing urbanicity. The new urbanicity metric was more predictive than either a governmentally defined rural/urban dichotomous variable or a population density variable. One reason for this was that 23% of cells within politically defined rural areas exhibited lower risk, more like those normally associated with “urban” locations.
Are dogs associated with infections by a skin burrowing flea in Kenya? Masanobu Ono and I with Kensuke Goto, Satoshi Kaneko, mwatasa Changoma just published a paper on #tungiasis in the journal Tropical Medicine and Health.
Most people haven’t heard of tungiasis, an ectopic skin disease caused by the skin burrowing parasite, T. pentrans. It causes itching, pain, is associated with serious secondary bacterial infections, gangrene, social exclusion and debilitation. It primarily afflicts the very young and very old and is found almost exclusively in the poorest parts of the poorest parts of the world. It fits the classic definition of a neglected tropical disease.
We explored associations of wildlife and domesticated animals with household level tungiasis in Kenya using a two stage complex sampling based survey in an area adjacent to a wildlife preserve.
Tungiasis is a ectopic skin disease caused by some species of fleas in the Tunga genus, most notably T. penetrans. The disease afflicts poor and marginalized communities in developing countries. Transmission of tungiasis comprises a complex web of factors including domesticated animals and wildlife. This research explores animal and environmental risk factors for tungiasis in an area adjacent to a wildlife reserve in Kwale, Kenya.
A two-stage complex sampling strategy was used. Households were selected from three areas in and around Kwale Town, Kenya, an area close to the Kenyan Coast. Households were listed as positive if at least one member had tungiasis. Each household was administered a questionnaire regarding tungiasis behaviors, domesticated animal assets, and wild animal species that frequent the peridomiciliary area. Associations of household tungiasis were tests with household and environmental variables using regression methods.
The study included 319 households. Of these, 41 (12.85%) were found to have at least one person who had signs of tungiasis. There were 295 (92.48%) households that possessed at least one species of domesticated animal. It was reported that wildlife regularly come into the vicinity of the home 90.59% of households. Presence of dogs around the home (OR 3.85; 95% CI 1.84; 8.11) and proximity to the park were associated with increased risk for tungiasis infestation in humans in a multivariate regression model.
Human tungiasis is a complex disease associated with domesticated and wild animals. Canines in particular appear to be important determinants of household level risk.
There really isn’t much out there. I found 15 papers on PubMed and Web of Science. I am looking for more.
(Davidson, 1970; Erulu, Okumu, Ochola, & Gikunju, 2018)
I found two case reports. The first was from 1970 documenting a case of a white woman being bitten in Voi when a black-necked spitting cobra (Naja nigricollis) entered her bed at night. She received prompt care of polyvalent antivenom, travelled to Mombasa the next day, received treatment again and was relatively mobile within a week. It too three months for a hole in her foot to finally heal and for normal sensation to return to her toes.
The second documented a bite from a black mamba (Dendroaspis polylepis) in Watamu. A 13-year-old boy presented to Watamu Hospital with labored breathing, frothing at the mouth, severe ptosis, pupils non-responsive with unreadable blood pressure and elevated heat rate. He was administered the SAVP polyvalent antivenom and the boy recovered.
Hospital based surveillance and clinician surveys
(Coombs et al., 1997; Ochola, Okumu, Muchemi, Mbaria, & Gikunju, 2018; M. Okumu et al., 2018; M. O. Okumu et al., 2019; Ooms et al., 2020)
Coombs, et al gathered data from four areas of Kenya using Ministry of Health records. It was found that bite cases varied by region. Documented deaths are rare. The incidence rate of snakebites varied by region, with Kakamega being low and areas like Samburu and Baringo being high. Documentation of snake bites was often incomplete. Many bites were recorded as “Other” in hospital records. Though environmental factors and habitats account for some variation in bite incidence rates, a lack of coordination of health facilities and inconsistent record keeping might also be a factor. Authors conclude that surveillance capacity needs to improve and that community should be educated to identify bites and provide appropriate treatment (i.e. only using tourniquets for neurotoxic bites from snakes like mambas.) Transport and proximity are noted as barriers to treatment.
Ochola, et al. Study on snakebites from four hospitals including Kakamega Provincial, Makueni District and two others. Two year retrospective study of hospital records form 2007-2009. 176 total bites, 91 in 2009. Bites peaked at 1-15 years of age, 132/176 bites occurred on the lower extremities. 49/176 were given antivenom. Most bites occurred in the dry season, in the bush and in the evening. Mortality was 2.27%. Authors found that antivenom was often not available, and use was inconsistent. Patients presented to hospitals 2 to 6 hours after the bite, mostly due to travel distance. 75% if clinicians believe that patients saw traditional healers before arriving at the hospital. Manual laborers at highest risk.
Ooms et al. study of health care workers in three countries including Kenya. HCWs reported that there was no gender disparity in snakebite victims, that most victims are between 21 and 30 and that most people are bitten when conducting farm related activities or walking. Only 12% of HCWs received training in snakebite management. Only 20% claimed that medicines were available. Snakebite incidence occurred in both urban and rural areas of all countries. Half of all respondents claimed that people seek traditional treatments before coming to formal facilities.
Okumu et al Paper on general poisonings. Snakebites are only one part of the paper but make up 33% of all cases that appeared at Jaramogi Oginga Odinga Teaching and Referral Hospital. Antivenom used in 58% of all snakebite case. “Black snakes” accounted for 37% of bites. Victims were not able to identify snake species in 38.6% of bites.
Okumu, 2019 Paper on cost of snakebite treatment. 127 snakebite victims attending JOOOTRH between January 2011 and Dec 2016. Most victims were 13024 years of age, 64 were female, 94 were from rural areas, 92 were bitten on the lower limbs. 49 bitten at night, 43 attempted to self-treat, median time to the hospital was 4.5 hours. Outcomes included cellulitis, compartment syndrome, gangrenous foot, psychiatric disorder and death. 1-5 days in the hospital. Median cost $26. Authors call for public health programs to educate the public on how to identify and treat snakebites.
(Snow et al., 1994)
Retrospective study of 4,712 households. Most bites were not from venomous snakes. Most people identified both venomous and non-venomous snakes as being potentially venomous. 68% of people sought treatment from traditional healers. Authors suggest that traditional healers be integrated int primary health care and hospital-based systems. Household heads were approached and administered a questionnaire in Kilifi and ask to retrospectively report bites. Out of 4,712 visits there were 121 case of snake bite reported, 57% were male. Most were Giriama. 55% were bitten at night. A73% on the foot. 94% bitten outdoors. Only 39% could reliably describe the snake. No deaths were recorded. 79% performed some kind of first aid immediately after the bite. 88% sought treatment, with 78% visiting the healer. Only 29% visited a hospital. There was evidence to suggest clustering of bites.
(Anne-Sophie, Neil, & Aida, 2017; Eucabeth & Augustine, 2017; Omara, 2020; B. O. Owuor & Kisangau, 2006; Bethwell O. Owuor, Mulemi, & Kokwaro, 2005)
(Benson, Mohamed, Soliman, Hassan, & Abou Mandour, 2017; Harrison et al., 2017; Omara, 2020)
Anne-Sophie, D., Neil, D. B., & Aida, C.-S. (2017). Medicinal Plant Trade in Northern Kenya: Economic Importance, Uses, and Origin^sup 1. Economic Botany, 71(1), 13.
Benson, R. A., Mohamed, N. M. A., Soliman, M., Hassan, M., & Abou Mandour, M. A. (2017). Application of k 0-INAA for the determination of essential and toxic elements in medicinal plants from West Pokot County, Kenya. Journal of Radioanalytical and Nuclear Chemistry, 314(1), 23. Retrieved from https://link.springer.com/content/pdf/10.1007%2Fs10967-017-5370-3.pdf
Coombs, M. D., Dunachie, S. J., Brooker, S., Haynes, J., Church, J., & Warrell, D. A. (1997). Snake bites in Kenya: a preliminary survey of four areas. Transactions of the Royal Society of Tropical Medicine and Hygiene, 91(3), 319-321. doi:10.1016/s0035-9203(97)90091-2
Davidson, R. A. (1970). Case of African cobra bite. British medical journal, 4(5736), 660-660. doi:10.1136/bmj.4.5736.660
Erulu, V., Okumu, M., Ochola, F., & Gikunju, J. (2018). Revered but Poorly Understood: A Case Report of Dendroaspis polylepis (Black Mamba) Envenomation in Watamu, Malindi Kenya, and a Review of the Literature. Tropical medicine and infectious disease, 3(3), 104. doi:10.3390/tropicalmed3030104
Eucabeth, O. a.-M. a., & Augustine, A. (2017). Identity Construction in Three AbaGusii Bewitchment Narratives. International Journal of Society, Culture & Language, 5(1), 29.
Harrison, R. A., Oluoch, G. O., Ainsworth, S., Alsolaiss, J., Bolton, F., Arias, A. S., . . . Casewell, N. R. (2017). Preclinical antivenom-efficacy testing reveals potentially disturbing deficiencies of snakebite treatment capability in East Africa. PLoS Negl Trop Dis, 11(10), e0005969. doi:10.1371/journal.pntd.0005969
Ochola, F. O., Okumu, M. O., Muchemi, G. M., Mbaria, J. M., & Gikunju, J. K. (2018). Epidemiology of snake bites in selected areas of Kenya. Pan Afr Med J, 29, 217. doi:10.11604/pamj.2018.29.217.15366
Okumu, M., Patel, M., Bhogayata, F., Olweny, I., Ochola, F., & Onono, J. (2018). Acute Poisonings at a Regional Referral Hospital in Western Kenya. Tropical medicine and infectious disease, 3(3), 96. doi:10.3390/tropicalmed3030096
Okumu, M. O., Patel, M. N., Bhogayata, F. R., Ochola, F. O., Olweny, I. A., Onono, J. O., & Gikunju, J. K. (2019). Management and cost of snakebite injuries at a teaching and referral hospital in Western Kenya. F1000Res, 8, 1588. doi:10.12688/f1000research.20268.1
Omara, T. (2020). Plants Used in Antivenom Therapy in Rural Kenya: Ethnobotany and Future Perspectives. J Toxicol, 2020, 1828521. doi:10.1155/2020/1828521
Ooms, G. I., Van Oirschot, J., Waldmann, B., Von Bernus, S., Van Den Ham, H. A., Mantel-Teeuwisse, A. K., & Reed, T. (2020). The Current State of Snakebite Care in Kenya, Uganda, and Zambia: Healthcare Workers’ Perspectives and Knowledge, and Health Facilities’ Treatment Capacity. The American Journal of Tropical Medicine and Hygiene. doi:10.4269/ajtmh.20-1078
Owuor, B. O., & Kisangau, D. P. (2006). Kenyan medicinal plants used as antivenin: a comparison of plant usage. J Ethnobiol Ethnomed, 2(1), 7. doi:10.1186/1746-4269-2-7
Owuor, B. O., Mulemi, B. A., & Kokwaro, J. O. (2005). Indigenous Snake Bite Remedies of the Luo of Western Kenya. Journal of Ethnobiology, 25(1), 129-141. doi:10.2993/0278-0771(2005)25[129:Isbrot]2.0.Co;2
Snow, R. W., Bronzan, R., Roques, T., Nyamawi, C., Murphy, S., & Marsh, K. (1994). The prevalence and morbidity of snake bite and treatment-seeking behavior among a rural Kenyan population. Annals of Tropical Medicine and Parasitology, 88.
Ancestor worship is a common theme in African lore, particulary in the traditional arts. So while people are singing the praises of their dead relatives, I always wanted to ask what to do if my ancestors were horrible people?
I was recently speaking with some people whose parents were refugees from Romania, ostensibly people who were fleeing life under the dictator Nicolae Ceaușescu, a forgotten piece of Stalinist work who made the lives of Romanians miserable for decades. While Ceaușescu and his government were vile, the people who came to the US were refugees and likely middle class families decended from peasants back home.
The contrast with my and many Americans’ heritage is stark. I am decended from a family of Mitchells, a distinguished Scottish family of wealthy means who decided to take a gamble and invest in agricultural ventures in the Southern United States. The first to come was a man named Thomas Mitchell, my maternal great x 10 grandfather, who arrived in US, fought in the Revolutionary War and set subsequently set up shop for the family business in Georgia.
Thomas, like many Scots who came to the Southern United States, came to profit not only off land and agricultural products that could be exported to Europe, but also off the promise of cheap, forced labor from Africa. Thomas Mitchell was a slaver.
From slave based agriculature, the Mitchell family became extremely wealthy in the South, producing numerous politicians, lawyers, administrators and academics. There is still a county named for the Mitchell family in Georgia.
In 1836, the Mitchell family expanded their land holdings by assembling a militia of 75 men and committing a genocide against the Native American residents of their land “in which all the Indians except five were killed, their arms, campage, etc. falling into the hands of the whites.”
There are others, but the point is, does it make sense to venerate one’s ancestors when they were clearly committing crimes against humanity? The Romanians I spoke with probably have terrible members of their family, but likely have not had their lives shaped by a horrible past.
I am not unique. Just about any white person in the South whose family was their during the 18th and 19th centuries was involved in the buying, selling and use of humans. If they have money now, it is a direct result of slavery and the ethnic cleansing of Native Americans in the South. We should never forget, because that’s how we got here, the past that shapes our present. Our current lives were made possible by terrible people doing reprehensible things to other people.
So no, not going to sing any praise songs to my ancestors any time soon. Maybe I’ll do the opposite instead.
New chapter from myself in a Springer volume: “Access to Health Care in Sub-Saharan Africa: Challenges in a Changing Health Landscape in a Context of Development”
I wrote a chapter for “Health in Ecological Perspectives in the Anthropocene” edited by Watanabe Toru and Watanabe Chiho. I have no idea if they are related. Either way, my chapter “Access to Health Care in Sub-Saharan Africa: Challenges in a Changing Health Landscape in a Context of Development” occupies pages 95-106 in the volume.
Check it out, you can buy the book through Amazon for a cool $109, or just my chapter through the Springer site for $29 or you can simply write me and I’ll give you a synopsis.
Here’s the abstract for the book:
This book focuses on the emerging health issues due to climate change, particularly emphasizing the situation in developing countries. Thanks to recent development in the areas of remote sensing, GIS technology, and downscale modeling of climate, it has now become possible to depict and predict the relationship between environmental factors and health-related event data with a meaningful spatial and temporal scale. The chapters address new aspects of environment-health relationship relevant to this smaller scale analyses, including how considering people’s mobility changes the exposure profile to certain environmental factors, how considering behavioral characteristics is important in predicting diarrhea risks after urban flood, and how small-scale land use patterns will affect the risk of infection by certain parasites, and subtle topography of the land profile. Through the combination of reviews and case studies, the reader would be able to learn how the issues of health and climate/social changes can be addressed using available technology and datasets.
The post-2015 UN agenda has just put forward, and tremendous efforts have been started to develop and establish appropriate indicators to achieve the SDG goals. This book will also serve as a useful guide for creating such an indicator associated with health and planning, in line with the Ecohealth concept, the major tone of this book. With the increasing and pressing needs for adaptation to climate change, as well as societal change, this would be a very timely publication in this trans-disciplinary field.
I am always looking for free alternatives to ArcGIS for making pretty maps. R is great for graphics and the new-to-me ggmap package is no exception.
I’m working with some data from Botswana for a contract and needed to plot maps for several years of count based data, where the GPS coordinates for facilities were known. ArcGIS is unwieldy for creating multiple maps of the same type of data based on time points, so R is an ideal choice…. the trouble is the maps I can easily make don’t look all that good (though with tweaking can be made to look better.)
ggmap offered me an easy solution. It downloads a topographic base map from Google and I can easily overlay proportionally sized points represent counts at various geo-located points. This is just a map of Botswanan health facilities (downloaded from Humanitarian Data Exchange) with the square of counts chosen from a normal distribution. The results are rather nice.
#read in grographic extent and boundary for bots
btw <- admin<-readOGR(“GIS Layers/Admin”,”BWA_adm2″) #from DIVA-GIS
# fortify bots boundary for ggplot
btw_df <- fortify(btw)
# get a basemap
btw_basemap <- get_map(location = “botswana”, zoom = 6)
# get the hf data
# create random counts
# Plot this dog
geom_polygon(data=btw_df, aes(x=long, y=lat, group=group), fill=”red”, alpha=0.1) +
geom_point(data=HFs.open.street.map, aes(x=X, y=Y, size=Counts, fill=Counts), shape=21, alpha=0.8) +
scale_size_continuous(range = c(2, 12), breaks=pretty_breaks(5)) +
scale_fill_distiller(breaks = pretty_breaks(5))