sub-Saharan East Africa Research Articles

Salmonella Typhi whole genome sequencing in Rwanda shows a diverse historical population with recent introduction of haplotype H58.

Salmonella enterica serovar Typhi (S. Typhi) is the cause of typhoid fever, presenting high rates of morbidity and mortality in low- and middle-income countries. The H58 haplotype shows high levels of antimicrobial resistance (AMR) and is the dominant S. Typhi haplotype in endemic areas of Asia and East sub-Saharan Africa. The situation in Rwanda is currently unknown and therefore to reveal the genetic diversity and AMR of S. Typhi in Rwanda, 25 historical (1984-1985) and 26 recent (2010-2018) isolates from Rwanda were analysed using whole genome sequencing (WGS). WGS was locally implemented using Illumina MiniSeq and web-based analysis tools, thereafter complemented with bioinformatic approaches for more in-depth analyses. Whereas historical S. Typhi isolates were found to be fully susceptible to antimicrobials and show a diversity of genotypes, i.e 2.2.2, 2.5, 3.3.1 and 4.1; the recent isolates showed high AMR rates and were predominantly associated with genotype 4.3.1.2 (H58, 22/26; 84,6%), possibly resulting from a single introduction in Rwanda from South Asia before 2010. We identified practical challenges for the use of WGS in endemic regions, including a high cost for shipment of molecular reagents and lack of high-end computational infrastructure for the analyses, but also identified WGS to be feasible in the studied setting and giving opportunity for synergy with other programs.

The ISCAP in the Shadow of the Russian-Ukrainian War

After the shock of the coronavirus, the world was hit by another blow: the Russian-Ukrainian war. This had a number of effects on the world, causing inflation and an energy price explosion. In the case of Africa, even food security was at risk due to the decline in Russian and Ukrainian grain. However, what is chaos for the world is an opportunity for jihadist movements to gain strength, as the burden on citizens increases social discontent. The situation in sub-Saharan East Africa is no different. The Islamic State's youngest province, ISCAP (Islamic State of Central Africa Province), created in 2019, remains dangerous, although the jihadist movements that make it up are not achieving the spectacular successes of the past. The Allied Democratic Forces (ADF) is based in the Congo-Uganda border region, while al-Shabaab in Mozambique has emerged in the northern province of Cabo Delgado. Their exact links to the Islamic State are not fully known, but recent reports suggest that the Islamic State of Somalia may be a center of back-and-forth communication between the two parties. The study focuses on ISCAP and the period since the Russian-Ukrainian war. In other words, what trends can be observed, how dangerous they could be and, most importantly, what opportunities they face and what kind of response is coming from the security forces. For the status of jihadist organisations, I refer to Stig Jarle Hansen's book Horn, Sahel and Rift, published in 2019. For the others, I rely on reports, analyses and, above all, recent news that may bring about changes in the way things have been done so far, one example being the LNG project being built in Cabo Delgado.

Properties and emission factors of cloud condensation nuclei from biomass cookstoves – observations of a strong dependency on potassium content in the fuel

Abstract. Residential biomass combustion is a significant source of aerosol particles on regional and global scales influencing climate and human health. The main objective of the current study was to investigate the properties of cloud condensation nuclei (CCN) emitted from biomass burning of solid fuels in different cookstoves mostly of relevance to sub-Saharan east Africa. The traditional three-stone fire and a rocket stove were used for combustion of wood logs of Sesbania and Casuarina with birch used as a reference. A natural draft and a forced-draft pellet stove were used for combustion of pelletised Sesbania and pelletised Swedish softwood alone or in mixtures with pelletised coffee husk, rice husk or water hyacinth. The CCN activity and the effective density were measured for particles with mobility diameters of ∽65, ∽100 and ∽200 nm, respectively, and occasionally for 350 nm particles. Particle number size distributions were measured online with a fast particle analyser. The chemical composition of the fuel ash was measured by application of standard protocols. The average particle number size distributions were by number typically dominated by an ultrafine mode, and in most cases a soot mode was centred around a mobility diameter of ∽150 nm. The CCN activities decreased with increasing particle size for all experiments and ranged in terms of the hygroscopicity parameter, κ, from ∽0.1 to ∽0.8 for the ultrafine mode and from ∽0.001 to ∽0.15 for the soot mode. The CCN activity (κ) of the ultrafine mode increased (i) with increasing combustion temperature for a given fuel, and (ii) it typically increased with increasing potassium concentration in the investigated fuels. The primary CCN and the estimated particulate matter (PM) emission factors were typically found to increase significantly with increasing potassium concentration in the fuel for a given stove. In order to link CCN emission factors to PM emission factors, knowledge about stove technology, stove operation and the inorganic fuel ash composition is needed. This complicates the use of ambient PM levels alone for estimation of CCN concentrations in regions dominated by biomass combustion aerosol, with the relation turning even more complex when accounting for atmospheric ageing of the aerosol.

Three Decades of Land Cover Change in East Africa

Population growth rates in Sub-Saharan East Africa are among the highest in the world, creating increasing pressure for land cover conversion. To date, however, there has been no comprehensive assessment of regional land cover change, and most long-term trends have not yet been quantified. Using a designed sample of satellite-based observations of historical land cover change, we estimate the areas and trends in nine land cover classes from 1998 to 2017 in Ethiopia, Kenya, Uganda, Malawi, Rwanda, Tanzania, and Zambia. Our analysis found an 18,154,000 (±1,580,000) ha, or 34.8%, increase in the area of cropland in East Africa. Conversion occurred primarily from Open Grasslands, Wooded Grasslands, and Open Forests, causing a large-scale reduction in woody vegetation classes. We observed far more conversion (by approximately 20 million hectares) of woody classes to less-woody classes than succession in the direction of increasing trees and shrubs. Spatial patterns within our sample highlight regional land cover conversion hotspots, such as the Central Zambezian Miombo Woodlands, as potential areas of concern related to the conservation of natural ecosystems. Our findings reflect a rapidly growing population that is moving into new areas, with a 43.5% increase in the area of Settlements over the three-decade period. Our results show the areas and ecoregions most impacted by three decades of human development, both spatially and statistically.

Maternal, neonatal and children´s health in Sub-Saharan East Africa

Maternal, neonatal and children´s health in Sub-Saharan East Africa

District Effect Appraisal in East Sub-Saharan Africa: Combating Childhood Anaemia.

Background Anaemia in children is a significant health problem that receives little attention. This study aimed at determining the factors significantly associated with anaemia in children aged 6 to 59 months in Kenya, Malawi, Tanzania, and Uganda while accounting for the spatial heterogeneity within and between the districts of the four countries. In addition, the performance of the districts with regard to their impact on anaemia was assessed and ranked. Methods A generalised additive mixed model with a spatial effect based on the geographical coordinates of the clusters was used. A district-level random effect was included to further account for the heterogeneity as well as to rank the performance of the districts based on the best linear unbiased prediction (BLUP). Results The results depicted significant spatial heterogeneity between and within the districts of the countries. After accounting for such spatial heterogeneity, child-level characteristics (gender, malaria test result, and mother's highest education level), household-level characteristics (household size, household's wealth index Z-score, the type of toilet facility available, and the type of place of residence), and the country of residence were found to be significantly associated with the child's anaemia status. There was a significant interaction between the type of place of residence and the country of residence. Based on the BLUP for the district-level random effect, the top 3 best- and worst-performing districts within each country were identified. Conclusion The ranking of the performance of the districts allows for the worst-performing districts to be targeted for further research in order to improve their anaemia control strategies, as well as for the best-performing districts to be identified to further determine why they are performing better and then to use these districts as role models in efforts to overcome childhood anaemia.

Maize Lethal Necrosis: An Emerging, Synergistic Viral Disease.

Maize lethal necrosis (MLN) is a disease of maize caused by coinfection of maize with maize chlorotic mottle virus (MCMV) and one of several viruses from the Potyviridae, such as sugarcane mosaic virus, maize dwarf mosaic virus, Johnsongrass mosaic virus or wheat streak mosaic virus. The coinfecting viruses act synergistically to result in frequent plant death or severely reduce or negligible yield. Over the past eight years, MLN has emerged in sub-Saharan East Africa, Southeast Asia, and South America, with large impacts on smallholder farmers. Factors associated with MLN emergence include multiple maize crops per year, the presence of maize thrips ( Frankliniella williamsi), and highly susceptible maize crops. Soil and seed transmission of MCMV may also play significant roles in development and perpetuation of MLN epidemics. Containment and control of MLN will likely require a multipronged approach, and more research is needed to identify and develop the best measures.

Practical Challenges and Perspectives for the Development of Neurosurgery in a Peripheral East African Hospital During a One-Volunteer Midterm Mission.

Several strategies have been proposed for developing and spreading surgical specialties in Sub-Saharan East Africa. Regarding neurosurgery, improvements are coming from the cooperation between Western and African institutes by means of the World Federation of Neurological Surgeons and independent organizations but, far from big cities and more equipped hospitals, shortcomings in the delivery of services persist. Through the application of 1 formally trained neurosurgeon volunteer, the Foundation for International Education in Neurological Surgery and Neurocirugía, Educación y Desarrollo coordinated a 2-month neurosurgical project at Mathari Consolata Hospital in Nyeri (Kenya), designed to analyze critical points and to find suggestions for initiating and developing a neurosurgical service, providing in the meantime clinical and surgical care for patients. During the mission, general and local issues limiting the neurosurgical activities at the hospital were studied. They were discussed with the hospital board and the project supervisors, thereby ensuring short-term and medium-term solutions and possible future cooperation with the hospital. The volunteer also carried out clinics and surgery for neuro cases and neurosurgical training for nurses and doctors. The model proposed should be considered a preliminary and immersive survey to evaluate the eligibility of a decentralized East African hospital to interface with neurosurgical activities, through the support of experienced local institutes and Western organizations. Host hospitals would also have the chance to enhance clinical services currently lacking and to train its personnel at low cost. The program may represent a rewarding personal and professional opportunity for young trained neurosurgeons, which also addresses the contemporary shortage of local specialists.

Additional specimens of Diceros (Perissodactyla, Rhinocerotidae) from the Upper Miocene Nakali Formation in Nakali, central Kenya

An upper incisor and upper and lower cheek teeth of Rhinocerotidae from the Upper Miocene of Nakali in central Kenya are described. Those specimens are identified as Diceros sp. The present study confirms the presence of Diceros in sub-Saharan East Africa during Vallesian as noted by several studies. The present result and the fossil records of Diceros in Africa and Eurasia suggest that Diceros might have migrated to Eurasia from Africa by Vallesian, although more fossil records and detailed phylogenetic analysis of Diceros are needed to discuss this hypothesis.

A new Elasmotheriini (Perissodactyla, Rhinocerotidae) from the upper Miocene of Samburu Hills and Nakali, northern Kenya

Several rhinocerotid cheek teeth and mandibular fragments from the upper Miocene of the Samburu Hills and Nakali in northern Kenya are described. These specimens show characteristics that place them in the Tribe Elasmotheriini such as a constricted protocone, a developed antecrochet, and coronal cement. The present specimens are compared with other Elasmotheriini species from Eurasia and sub-Saharan East Africa. They are found to be morphologically different from the previously known species of Elasmotheriini. Morphologically, they are most similar to Victoriaceros kenyensis from the middle Miocene of Kenya, but differ from V. kenyensis in having the upper molars with the simple crochet, lingual groove of the protocone and enamel ring in the medisinus. Therefore, the present specimens are assigned to a new genus and species of Elasmotheriini: Samburuceros ishidai. A cladistic analysis tentatively places S. ishidai nov. gen., nov. sp. as a sister taxon of V. kenyensis. However, questions remain regarding a further detailed discussion of the phylogenetic relationship between the African Elasmotheriini and other Eurasian taxa because of the incompleteness of the specimens from Africa, as already noticed by several researchers.

Molecular phylogeny and biogeography of the land snail family Hygromiidae (Gastropoda: Helicoidea)

The Hygromiidae is a highly diverse group of land snails with a distribution range stretching throughout the Palearctic region from the Macaronesian Islands to the Russian Far East and reaching southwards to the north-eastern Ethiopian region. So far, the classification of the family largely rested on the structure of the dart apparatus, an accessory genital organ. We used nuclear and mitochondrial DNA sequences of almost all genera to reconstruct the phylogeny of the Hygromiidae. Several of the clades found in the molecular phylogenetic analyses represent regional radiations that partly show a high variation in the structure of the dart apparatus. Thus, several of the currently accepted subdivisions of the family, which included taxa with similar dart apparatus from different regions, turned out to be polyphyletic. We newly delimit three subfamilies within the family, Hygromiinae, Leptaxinae and Trochulinae on the basis of our phylogenetic analyses. The Hygromiinae are further subdivided into Hygromiini and Perforatellini trib. nov. The Leptaxinae are classified in Leptaxini, Metafruticicolini and Cryptosaccini trib. nov. The Trochulinae are the most diverse group including Ciliellini, Archaicini, Ganulini trib. nov., Urticicolini trib. nov., Trochulini, Caucasigenini trib. nov., Ashfordini trib. nov., Halolimnohelcini and Monachaini. Moreover, two new genera, Coronarchaica gen. nov. from Central Asia and Noricella gen. nov. from the Alps, are described. The Hygromiidae originated in the western Palaearctic, from where the Central Asian mountain regions, the Macaronesian Islands, the Caucasus region and sub-Saharan East Africa were colonized. The radiation of the Hygromiidae as well as those of several other land snail families was dispersal limited. Because of the low dispersal abilities of land snails, the period until an isolated region is colonized by a group by chance dispersal is comparatively longer than the period necessary for morphological and ecological diversification of the group within the newly colonized region. Some of the regional radiations coincided with orogeny in the respective areas and were probably triggered by the development of geographical barriers and new niches.

Profits and Charitable Missions: Funding Volunteerism in the Developing World

Several strategies have been proposed for developing and spreading surgical specialties in Sub-Saharan East Africa. Regarding neurosurgery, improvements are coming from the cooperation between Western and African institutes by means of the World Federation of Neurological Surgeons and independent organizations but, far from big cities and more equipped hospitals, shortcomings in the delivery of services persist.Through the application of 1 formally trained neurosurgeon volunteer, the Foundation for International Education in Neurological Surgery and Neurocirugía, Educación y Desarrollo coordinated a 2-month neurosurgical project at Mathari Consolata Hospital in Nyeri (Kenya), designed to analyze critical points and to find suggestions for initiating and developing a neurosurgical service, providing in the meantime clinical and surgical care for patients.During the mission, general and local issues limiting the neurosurgical activities at the hospital were studied. They were discussed with the hospital board and the project supervisors, thereby ensuring short-term and medium-term solutions and possible future cooperation with the hospital. The volunteer also carried out clinics and surgery for neuro cases and neurosurgical training for nurses and doctors.The model proposed should be considered a preliminary and immersive survey to evaluate the eligibility of a decentralized East African hospital to interface with neurosurgical activities, through the support of experienced local institutes and Western organizations. Host hospitals would also have the chance to enhance clinical services currently lacking and to train its personnel at low cost. The program may represent a rewarding personal and professional opportunity for young trained neurosurgeons, which also addresses the contemporary shortage of local specialists.

Genetic Polymorphisms of TLR4 and MICA are Associated with Severity of Trachoma Disease in Tanzania.

To examine the association of TLR4 Asp299Gly and MICA exon 5 microsatellites polymorphisms with severity of trachoma in a sub-Saharan East Africa population of Tanzanian villagers. The samples were genotyped for MICA exon 5 microsatellites and the TLR4 299 A/G polymorphism by Restriction Fragment Length Polymorphism (RFLP), and GeneScan®, respectively. The association of TLR4 Asp299Gly and MICA exon 5 microsatellites with inflammatory trachoma (TI) and trichiasis (TI) were examined. The results showed an association between TLR4 and MICA polymorphisms and trachoma disease severity, as well as with protection. TLR4 an allele was significantly associated with inflammatory trachoma (p=0.0410), while the G allele (p=0.0410) was associated with protection. TLR4 and MICA may modulate the risk of severity to trachoma disease by modulating the immune response to Ct. In addition; the increased frequency of MICA-A9 heterozygote in controls may suggest a positive selection of these alleles in adaptation to environments where Ct is endemic.

Number of People Blind or Visually Impaired by Cataract Worldwide and in World Regions, 1990 to 2010.

To estimate prevalence and number of people visually impaired or blind due to cataract. Based on the Global Burden of Diseases Study 2010 and ongoing literature research, we examined how many people were affected by moderate to severe vision impairment (MSVI; presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60) due to cataract. In 2010, of overall 32.4 million blind and 191 million vision impaired, 10.8 million people were blind and 35.1 million were visually impaired due to cataract. Cataract caused worldwide 33.4% of all blindness in 2010, and 18.4% of all MSVI. These figures were lower in the high-income regions (<15%) and higher (>40%) in South and Southeast Asia and Oceania. From 1990 to 2010, the number of blind or visually impaired due to cataract decreased by 11.4% and by 20.2%, respectively; the age-standardized global prevalence of cataract-related blindness and MSVI reduced by 46% and 50%, respectively, and the worldwide crude prevalence of cataract-related blindness and MSVI reduced by 32% and 39%, respectively. The percentage of global blindness and MSVI caused by cataract decreased from 38.6% to 33.4%, and from 25.6% to 18.4%, respectively. This decrease took place in almost all world regions, except East Sub-Saharan Africa. In 2010, one in three blind people was blind due to cataract, and one of six visually impaired people was visually impaired due to cataract. Despite major improvements in terms of reduction of prevalence, cataract remains a major public health problem.

A systematic analysis of global anemia burden from 1990 to 2010.

Previous studies of anemia epidemiology have been geographically limited with little detail about severity or etiology. Using publicly available data, we estimated mild, moderate, and severe anemia from 1990 to 2010 for 187 countries, both sexes, and 20 age groups. We then performed cause-specific attribution to 17 conditions using data from the Global Burden of Diseases, Injuries and Risk Factors (GBD) 2010 Study. Global anemia prevalence in 2010 was 32.9%, causing 68.36 (95% uncertainty interval [UI], 40.98 to 107.54) million years lived with disability (8.8% of total for all conditions [95% UI, 6.3% to 11.7%]). Prevalence dropped for both sexes from 1990 to 2010, although more for males. Prevalence in females was higher in most regions and age groups. South Asia and Central, West, and East sub-Saharan Africa had the highest burden, while East, Southeast, and South Asia saw the greatest reductions. Iron-deficiency anemia was the top cause globally, although 10 different conditions were among the top 3 in regional rankings. Malaria, schistosomiasis, and chronic kidney disease-related anemia were the only conditions to increase in prevalence. Hemoglobinopathies made significant contributions in most populations. Burden was highest in children under age 5, the only age groups with negative trends from 1990 to 2010.

A systematic analysis of global anaemia burden between 1990 and 2010

BackgroundAnaemia is associated with increased maternal and neonatal mortality, with young children most at risk of developing long-term ramifications. Most previous studies have been geographically limited with little detail about severity or aetiology. In this analysis, we completed the most comprehensive survey of anaemia burden to date. MethodsUsing publicly available data, we estimated mild, moderate, and severe anaemia in 1990 and 2010 for 187 countries, both sexes, and 20 age groups. We then performed cause-specific attribution to 17 conditions using data and resources of the Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study 2010. FindingsGlobal anaemia prevalence in 2010 was 32·9%, causing 68·36 million years lived with disability (95% CI 40·98–107·54 million; 8·8% of the total for all conditions, 95% CI 6·3–11·7). Prevalence dropped for both sexes from 1990 to 2010, though more so for males. Females' prevalence was higher in most regions and age groups. South Asia and central, west, and east sub-Saharan Africa had the highest burden, while east, southeast, and south Asia saw the greatest reductions. Ten different conditions were among the top three in prevalence, depending on the region. Malaria, schistosomiasis, and chronic kidney disease-related anaemia were the only conditions to increase in prevalence. Haemoglobinopathies made significant contributions to the anaemia burden in both sexes, most regions, and all time periods. Burden was highest in children under 5 years old, the only age groups with negative trends from 1990 to 2010. InterpretationAnaemia is a heterogeneous and complex condition. Despite significant progress, many challenges remain. Regional differences remain stark, some conditions are growing as a proportion of overall anaemia, the gender gap is widening, and the total disease burden remains high. Worryingly, young children, the most vulnerable group, appear to be doing worse over the past 20 years. Targeted surveillance and intervention in high-risk populations should be a greater priority. FundingFunding for GBD 2010 was provided by the Bill & Melinda Gates Foundation.

HIV-malaria co-infection: effects of malaria on the prevalence of HIV in East sub-Saharan Africa

HIV and malaria have an overlapping distribution in tropical areas, particularly in sub-Saharan Africa, and any of their clinical, diagnostic and therapeutic interactions might have important effects on patient care and public health policy. Therefore, in the past decade research has been conducted on this topic. Cuadros et al. recently aggregated population-based HIV and malaria data across studies and concluded that malaria is a risk factor for concurrent HIV infection at the population level. Although there is a large geographical overlap between malaria and HIV, the age-distributions of the two are very different. Malaria infection in 2to 10-year-old children in the community is used as a proxy for malaria in adults aged 15–49 years. However, age-prevalence curves alter with transmission intensity. In high transmission areas, the peak is typically in younger children and when transmission decreases, the peak lowers and occurs at an older age till ultimately the whole population is at risk. Therefore, the authors need to consider which malaria metrics are the most relevant for adults who have different levels of acquired malaria immunity. More importantly, the authors presuppose that having malaria will increase an individual’s risk for becoming HIV seropositive. This does not seem as biologically plausible as the opposite presupposition; namely, when an individual is HIV seropositive, they have an increased risk of malaria infection. Indeed, there is increasing evidence that people who are infected with HIV are more susceptible to malaria and may be at risk of experiencing greater severity. As more of the demographic and health surveys continue to be conducted with a good assessment of both HIV and malaria simultaneously and adding parameters such as CD4 cell count, more information may become available leading to a better understanding of the causality of the reported association.

Authors' Response to: HIV-malaria co-infection: effects of malaria on the prevalence of HIV in East sub-Saharan Africa

Authors' Response to: HIV-malaria co-infection: effects of malaria on the prevalence of HIV in East sub-Saharan Africa

Fatty acid compositions of preterm and term colostrum, transitional and mature milks in a sub-Saharan population with high fish intakes

BackgroundThere are no data on the fatty acid (FA) compositions of preterm and term milks for sub-Saharan African populations with advancing lactation. However, it is generally acknowledged that our ancestors evolved in sub-Saharan East-Africa, where they inhabited the land-water ecosystems. MethodsWe compared the FA-compositions of preterm (28–36 weeks) and term (37–42) colostrum (2–5 day), transitional (6–15) and mature (16–56) milks in rural African women with stable dietary habits and lifelong high freshwater fish intakes. ResultsFrom colostrum to mature milk: the median docosahexaenoic acid (DHA) content decreased from 1.11 to 0.75; and arachidonic acid (AA) from 0.93 to 0.69g% in preterm milk. In term milk, DHA decreased from 0.81 to 0.53 and AA from 1.08 to 0.55g%. Medium-chain saturated-FA (MCSAFA) increased from 16.9 to 33.7, and 7.92–29.0g%, while mono-unsaturated FA (MUFA) decreased from 32.5 to 22.6, and 40.0–26.5g%, in preterm and term milk, respectively. Consistent with the literature, preterm colostrum contained higher DHA and MCSAFA, and lower MUFA compared to term colostrum. These differences vanished rapidly with advancing lactation. MUFA and MCSAFA were inversely related. ConclusionsThe presently found DHA in preterm colostrum and mature milks and AA in premature mature milk proved the highest reported in the literature so far, as derived from analysis with capillary GC-columns. We confirmed the much higher MCSAFA and lower MUFA contents in milk of rural African, compared to Westernized women. The milk FA composition of this traditional population might show us the FA composition on which our species evolved and consequently to which our genome has become adapted to optimally support (infant) health.

HIV-malaria co-infection: effects of malaria on the prevalence of HIV in East sub-Saharan Africa

To examine the association between malaria and HIV prevalence in East sub-Saharan Africa. Using large nationally representative samples of 19,735 sexually active adults from the 2003-04 HIV/AIDS indicator surveys conducted in Kenya, Malawi and Tanzania, and the atlas malaria project, we analysed the relationship between malaria and HIV prevalence adjusting for important socioeconomic and biological cofactors. In adjusted models, individuals who live in areas with high Plasmodium falciparum parasite rate (PfPR > 0.42) had increased estimated odds of being HIV positive than individuals who live in areas with low P. falciparum parasite rate (PfPR ≤ 0.10) [men: estimated odds ratio (OR) 2.24, 95% confidence interval (CI) 1.62-3.12; women: estimated OR 2.44, 95% CI 1.85-3.21]. This is the first study to report malaria as a risk factor of concurrent HIV infection at the population level. According to our results, individuals who live in areas with high P. falciparum parasite rate have about twice the risk of being HIV positive compared with individuals who live in areas with low P. falciparum parasite rate. Our work emphasizes the need for field studies focused on quantifying the interaction among parasitic infections and risk of HIV infection, and studies to explore the impact of control interventions. Programmes focused on reducing malaria transmission will be important to address, especially in HIV-infected individuals.