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.
Its always a thing to celebrate, getting these new papers out. This one covers a topic close to home. After years of doing global health work, I never thought I’d be doing domestic health and even less certain that I’d be covering topics just down the road from me.
Together with partners from Wayne State University (Health Urban Waters), UM-Dearborn and the University of Michigan Ann Arbor, we characterized the state of recurrent flooding in Detroit, MI and explore possible public health impacts. The article appears in the International Journal of Environmental Research in Public Health. This was extremely rewarding work.
Article is open access.
Household flooding has wide ranging social, economic and public health impacts particularly for people in resource poor communities. The determinants and public health outcomes of recurrent home flooding in urban contexts, however, are not well understood. A household survey was used to assess neighborhood and household level determinants of recurrent home flooding in Detroit, MI. Survey activities were conducted from 2012 to 2020. Researchers collected information on past flooding, housing conditions and public health outcomes. Using the locations of homes, a “hot spot” analysis of flooding was performed to find areas of high and low risk. Survey data were linked to environmental and neighborhood data and associations were tested using regression methods. 4803 households participated in the survey. Flooding information was available for 3842 homes. Among these, 2085 (54.26%) reported experiencing pluvial flooding. Rental occupied units were more likely to report flooding than owner occupied homes (Odd ratio (OR) 1.72 [95% Confidence interval (CI) 1.49, 1.98]). Housing conditions such as poor roof quality and cracks in basement walls influenced home flooding risk. Homes located in census tracts with increased percentages of owner occupied units (vs. rentals) had a lower odds of flooding (OR 0.92 [95% (CI) 0.86, 0.98]). Household factors were found the be more predictive of flooding than neighborhood factors in both univariate and multivariate analyses. Flooding and housing conditions associated with home flooding were associated with asthma cases. Recurrent home flooding is far more prevalent than previously thought. Programs that support recovery and which focus on home improvement to prevent flooding, particularly by landlords, might benefit the public health. These results draw awareness and urgency to problems of urban flooding and public health in other areas of the country confronting the compounding challenges of aging infrastructure, disinvestment and climate change.
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.
Is pollen associated with suicide? That’s the question we sought to answer. Pollen related allergic rhinitis is associated with depressive symptoms, discomfort, pain, sleep disruptions, isolation and reduced quality of life in people who have them. Our team, led by UM researcher Dr. Rachel Bergmans, set out to test associations of suicide mortality in Ohio with pollen exposures using data from Ohio’s vital records and a novel prognostic, model based raster of daily pollen counts from Dr. Allison Steiner’s team at UM’s College of Engineering.
We explored associations of suicide with exposure to four types of pollens and the paper can be found here (Open access for 50 days). Suicide is serious. Though the causes of suicide are complex, pollen allergies are associated with depressive symptoms, isolation, pain, discomfort and for some, complete debilitation. #suicide#pollen#epidemiology
Background Seasonal trends in suicide mortality are observed worldwide, potentially aligning with the seasonal release of aeroallergens. However, only a handful of studies have examined whether aeroallergens increase the risk of suicide, with inconclusive results thus far. The goal of this study was to use a time-stratified case-crossover design to test associations of speciated aeroallergens (evergreen, deciduous, grass, and ragweed) with suicide deaths in Ohio, USA (2007–2015).
Methods Residential addresses for 12,646 persons who died by suicide were linked with environmental data at the 4–25 km grid scale including atmospheric aeroallergen concentrations, maximum temperature, sunlight, particulate matter <2.5 μm, and ozone. A case-crossover design was used to examine same-day and 7-day cumulative lag effects on suicide. Analyses were stratified by age group, gender, and educational level.
Results In general, associations were null between aeroallergens and suicide. Stratified analyses revealed a relationship between grass pollen and same-day suicide for women (OR = 3.84; 95% CI = 1.44, 10.22) and those with a high school degree or less (OR = 2.03; 95% CI = 1.18, 3.49).
Conclusions While aeroallergens were generally not significantly related to suicide in this sample, these findings provide suggestive evidence for an acute relationship of grass pollen with suicide for women and those with lower education levels. Further research is warranted to determine whether susceptibility to speciated aeroallergens may be driven by underlying biological mechanisms or variation in exposure levels.
We published a new paper on Covid-19 and ER visits for suicide attempts/self harm incidents in Epidemiology and Community Health today
Rachel Bergmans, an epidemiologist from the University of Michigan Institute for Social Research (and soon the University of Michigan Medical School) and I recently wrote a paper on the impact of Covid-19 and Covid-19 policy in the state of Michigan on emergency room visits for suicide and self harm incidents.
I am happy to say that it appeared today in Epidemiology and Community Health and encourage everyone to read it here.
Many worried that Covid-19 and the resulting “lockdown” measures would result in rapid increases in suicide attempts due to increased unemployment and social isolation. We did not find an increase in ER visits for self harm and suicide attempts at the University of Michigan Hospital in Ann Arbor, MI. In fact, we found a decline in visits that continued into the winter.
Though it is impossible to know (from this data) what the actual reasons for this decline were, these results suggest that the Covid-19 crisis might not be comparable to previous economic downturns. It might suggest that efforts to financially support those left out of work by the shutdown might mitigate the worst effects of an rapid unemployment.
I am very proud of this work, here is the abstract:
Objective Determine the early impact of the COVID-19 pandemic on emergency department (ED) encounters for suicide attempt and intentional self-harm at a regional tertiary academic medical centre in Washtenaw County, Michigan, which is one of the wealthier and more diverse counties in the state.
Methods Interrupted time series analysis of daily ED encounters from October 2015 through October 2020 for suicide attempt and intentional self-harm (subject n=3002; 62% female; 78% Caucasian) using an autoregressive integrated moving average modelling approach.
Results There were 39.9% (95% CI 22.9% to 53.1%) fewer ED encounters for suicide attempt and intentional self-harm during the first 12 weeks of the COVID-19 pandemic (ie, on or after 10 March 2020, when the first cases of COVID-19 were identified in Michigan).
Conclusions Fewer individuals sought emergency care for suicide-related behaviour during the earlier phase of the COVID-19 pandemic than expected when compared to prior years. This suggests initial outbreaks of COVID-19 and state of emergency executive orders did not increase suicide-related behaviour in the short term. More work is needed to determine long-term impacts of the COVID-19 pandemic on suicide-related behaviour and whether there are high-risk groups.
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.
Among other things. Check out the full interview here:
To date, there has been no data on incidence of Covid 19 cases in the workplace in Michigan.
The State of Michigan, as part of Executive Order 2020-114 requires that businesses immediately notify the local public health department and any co-workers, contractors, or suppliers who may have come into contact with the person with a confirmed case of COVID-19 within 24 hours. Businesses must also shut down operations when any person is found to show symptoms of Covid 19 in the establishment and has a positive test.
But anecdotal reports are suggesting that compliance with the directive is spotty. No doubt, businesses will be hesitant to shut down operations with little notice or to draw undue attention to themselves. However, after one local business (so far the only one to do so) issued a public statement that one of their employees tested positive for the disease, the public is becoming skeptical of the private sector’s commitment to responding to potential exposures.
Rumors are flying through service workers that businesses are slow to respond or are actively covering up information on cases that have appeared in their workplaces. Of course, these are rumors and anecdotes, but even if the incidents are wholly unsubstantiated, public skepticism on social media is not. The public does not trust businesses, and particularly service businesses to adhere to the guidelines spelled out in the executive order.
Clearly, we are in real trouble. Cases have spiked in the past week, hospitalizations are up, and many states have lost or are about to lose the gains they have made. Hospitals in Texas are overflowing. Even the US military has extended bans on movement or personnel into specific states, most notably, my own while lifting them for other states.
We need businesses to adhere to the guidelines for reporting in the executive order, but we also need to use that data to inform the public on risks for infection when visiting businesses. While businesses are required to report to local health authorities, there is no indication that the data will be made public and very little indication that the data will be disseminated in a manner that will facilitate research on specific risks in different types of businesses.
Supposedly, you can call your local health department and they will tell you if you if you might have been exposed when you went to Place X. That requires a lot of work on the part of the consumer, and how are they going to know to ask about a specific business without having an alarm raised anyway? I can’t see how that can work.
Public health authorities and the private sector MUST work together to implement systems and information sharing that protects the public health. While businesses are right to be concerned about their survival, becoming the center of a superspreader event will be a public relations disaster as we saw in Lansing, MI over the weekend.
Bars and restaurants need to develop systems to inform customers when a staff member tests positive for Covid 19
Fauci noted that “Bars are bad news” during a Senate hearing on covid 19 today, and he’s right. No one should be going to a bar right now. No one should be playing music in a bar. No one should be working in a bar right now. Just a terrible idea all around.
But people are doing it anyway, and, though the risks are very high, there have to be systems in place to minimize that risk and help insure the safety of customers and workers.
At least two bars in Ann Arbor, MI have had staff members test positive for Covid 19 within the past week. One did the right thing. They shut down operations and had their entire staff tested immediately. A couple of days later, they issued a statement informing the public of what happened and what they did. The other has yet to do anything at all, unfortunately.
Closures and public statements are good things, but maybe there’s another step that businesses can take to inform customers in a timely manner. I suggest collected phone or email contact information from customers each night.
Businesses would send out a text or an email message informing the customer a staff member tested positive and it is possible that they may have been exposed to covid19 and should get tested and isolate as soon as possible.
As this system would be voluntary, no privacy would be violated. It is likely that most patrons would consent to receiving such notices. Personally, I would like to know. I would also like to receive that information sooner rather than later.
A QR code app based system such as that being implement in South Korea would be preferable, but it is unlikely that such a system would be acceptable in the US, aside from issues of cost. A simple email list might be an easy, low cost method of informing the public when they might have been at risk for infection.