Malaria epidemiology and stratification of incidence in the malaria elimination setting in Harari Region, Eastern Ethiopia

Plastic pollution in Harari region, Ethiopia: practices and impacts on health and environment

Plastic pollution poses a significant threat to the environment and human health on a global level. This study aimed to investigate plastic pollution in the Harari region of Ethiopia. The result indicated that 62% of respondents demonstrated good knowledge about plastic waste, and 59% of them perceived plastic waste as harmful. Polyethylene terephthalate, high-density polyethylene, polyvinyl chloride, low-density polyethylene, polypropylene, polystyrene, and polycarbonates were the types of plastic waste identified. Being female (AOR = 1.82), aged 15-45 (AOR = 1.82), married (AOR = 1.83), and having families >3 (AOR = 2.15) were significantly positively associated with good plastic waste management practice. Being illiterate (AOR = 0.52), and having poor knowledge about plastic waste (AOR = 0.54) were significantly negatively associated with poor management practice. The findings indicated that the Harari region is prone to adverse health and environmental effects from plastic pollution. Policies restricting plastic use, training municipal waste collectors and health extension workers, and improving public awareness are indispensable.

Bionomic characterization of Anopheles mosquitoes in the Ethiopian highlands and lowlands

BACKGROUND

The protective effectiveness of vector control in malaria relies on how the implemented tools overlap with mosquito species-specific compositions and bionomic traits. In Ethiopia, targeted entomological data enabling strategic decision-making are lacking around high-risk migrant worker camps in the lowlands and resident communities in the highlands-resulting in suboptimal malaria control strategies for both populations. This study investigates spatial and temporal mosquito behavior, generating baseline evidence that will improve malaria control for both migrant workers in the lowlands and their home communities in the highlands.

METHODS

Hourly Centers for Disease Control and Prevention (CDC) light trap collections were performed indoors and outdoors during the peak (October to December 2022) and minor (March to May 2023) malaria transmission seasons. These seasons coincide with the post-long rain and post-short rain seasons, respectively. Eight resident households were sampled from each of four villages in the highlands and eight households/farm structures on and near farms in four villages in the lowlands. The sampling occurred between 18:00 and 06:00. Spatiotemporal vector behaviors and hourly indoor and outdoor mosquito capture rates, used as a proxy for human biting rates, were calculated for overall catches and for individual species. Adult mosquitoes were identified using morphological keys, and a subset of samples were confirmed to species by sequencing ribosomal DNA internal transcribed spacer region 2 (ITS2) and/or mitochondrial DNA cytochrome c oxidase subunit 1 (Cox1).

RESULTS

In the highlands, 4697 Anopheles mosquitoes belonging to 13 morphologically identified species were collected. The predominant species of Anopheles identified in the highlands was An. gambiae sensu lato (s.l.) (n = 1970, 41.9%), followed by An. demeilloni (n = 1133, 24.1%) and An. cinereus (n = 520, 11.0%). In the lowland villages, 3220 mosquitoes belonging to 18 morphological species were collected. Anopheles gambiae s.l. (n = 1190, 36.9%), An. pretoriensis (n = 899, 27.9%), and An. demeilloni (n = 564, 17.5%) were the predominant species. A total of 20 species were identified molecularly, of which three could not be identified to species through comparison with published sequences. In highland villages, the indoor Anopheles mosquito capture rate was much greater than the outdoor rate. This trend reversed in the lowlands, where the rate of outdoor captures was greater than the indoor rate. In both highlands and lowlands, Anopheles mosquitoes showed early biting activities in the evening, which peaked between 18:00 and 21:00, for both indoor and outdoor locations.

CONCLUSIONS

The high diversity of Anopheles vectors and their variable behaviors result in a dynamic and resilient transmission system impacting both exposure to infectious bites and intervention effectiveness. This creates gaps in protection allowing malaria transmission to persist. To achieve optimal control, one-size-fits-all strategies must be abandoned, and interventions should be tailored to the diverse spatiotemporal behaviors of different mosquito populations.

A five years malaria surveillance data analysis of North Shewa zone, Amhara region, Ethiopia: July 2018 to June 2023

BACKGROUND

Malaria is a critical public health concern in Ethiopia, with significant socioeconomic consequences. Malaria data trend analysis is essential for understanding transmission patterns and adopting evidence-based malaria control measures. The purpose of this study was to determine the 5 year distribution of malaria in North Shewa zone, Amhara region, Ethiopia, in 2023.

METHODS

A descriptive cross-sectional study design was employed to analyse the 5 year trend of malaria surveillance data in the North Shewa zone of the Amhara regional, Ethiopia, spanning from July 2018 to June 2023. The malaria indicator data were gathered from the zone's public health emergency management database. Malaria data from the previous 5 years was collected, compiled, processed, and analysed using Microsoft Excel 2019.

RESULTS

Among a total of 434,110 suspected cases 47,889 (11.03%) cases were confirmed as malaria, with an average annual malaria incidence rate of 4.4 per 1000 population in the Zone. Malaria cases exhibited an increase from Epidemiological Week (Epi week) 37 to Epi week 49 (September to November) and again from Epi week 22 to week 30 (May to July). Individuals aged 15 and above, and all districts in the Zone except Angolela were notably affected by malaria.

CONCLUSION

Despite implementing various measures to reduce malaria incidence, the disease continues to persist in the zone. Therefore, the Zone Health Department should intensify its preventive and control efforts.

Plasmodium falciparum neonatal malaria with atypical presentation: a case series from southwestern Ethiopia

BACKGROUND

Neonatal malaria is defined as the detection of asexual stages of Plasmodium species in the cord blood within the first 28 days of life. It can be congenital or acquired through mosquito bites or blood transfusions. Neonates are generally considered to be relatively protected due to the multiple innate and acquired physiological protective effects present in neonates. However, in areas where malaria is endemic, the prevalence of malaria in neonates is high. The predominant clinical feature of malaria in neonates is fever. Other clinical manifestations of neonatal malaria include respiratory distress, pallor and anaemia, hepatomegaly, refusal to feed, jaundice and diarrhoea. Atypical presentations without fever can lead to inaccurate diagnosis and contribute to neonatal morbidity and mortality. Neonates from endemic areas with any of the above symptoms should be screened for malaria.

CASE PRESENTATION

We present a series of three cases of neonatal Plasmodium falciparum malaria that presented atypically without febrile episodes and were diagnosed and managed at Mizan-Tepi University Teaching Hospital between July and September 2023. The first patient presented with vomiting, refusal to feed, pallor, severe anaemia, and splenomegaly. The second patient presented with an inconsolable cry, failure to pass feces, abdominal distention, and anaemia. The third patient presented with vomiting and anaemia. All patients received a 7-day course of intravenous artesunate; the first patient also received a blood transfusion. All patients recovered and were discharged.

CONCLUSIONS

Partial immunity resulting from repeated malaria infections in endemic regions may result in the transfer of high levels of maternal Immunoglobulin G (IgG) antibodies through the placenta and can produce different atypical clinical presentations. In malaria-endemic areas, neonates presenting with any of the presenting signs and symptoms of malaria, including afebrile presentation, require malaria screening to avoid delays in diagnosis.

Ten-year trend analysis of malaria prevalence in Gindabarat district, West Shawa Zone, Oromia Regional State, Western Ethiopia

BACKGROUND

Malaria is a major public health concern in Ethiopia, where more than half of the population lives in malaria risk areas. While several studies have been conducted in different eco-epidemiological settings in Ethiopia, there is a notable scarcity of data on the prevalence of malaria in the Gindabarat district. Therefore, this study aimed to analyse 10-year trend of malaria prevalence in Gindabarat district, West Shawa Zone of Oromia, Western Ethiopia.

METHODS

A retrospective laboratory record review was conducted at Gindabarat General Hospital and Gindabarat District Health Office from September 2011 to August 2020. The retrieved data included the date of examination, age, sex and laboratory results of the blood smears, including the Plasmodium species identified. Data were summarized and presented in the form of tables, figures, and frequencies to present the results. The data were analysed using SPSS (version 25.0) and Microsoft Excel.

RESULTS

Over the course of 10 years, a total of 11,478 blood smears were examined in the public health facilities in the district. Of the total blood smears examined, 1372 (11.95%) were microscopically confirmed malaria. Plasmodium falciparum, Plasmodium vivax and mixed infections (P. falciparum and P. vivax) accounted for 70.77%, 20.55% and 8.67% of the cases, respectively. Malaria prevalence was significantly higher among individuals aged ≥ 15 years (12.60%, x2 = 13.6, df = 2, p = 0.001) and males (14.21%, x2 = 59.7, df = 1, p = 0.001). The highest number of malaria cases was recorded from September to November.

CONCLUSION

Malaria remains a public health problem in the district. P. falciparum was the most predominant parasite species in the area. Malaria prevalence was significantly higher among individuals aged ≥ 15 years and males. There was a remarkable fluctuation in the number of malaria cases in different months and years. In the study area malaria cases peaked in 2015 and 2017 then decreasing from 2017 to 2019, with sharp increase in 2020. Moreover, this study showed malaria cases were reported in all seasons and months, but the highest was observed from September to November. Strengthening malaria control activities is essential to further reduce the burden of malaria and pave the way for the anticipated elimination.

Malaria Prevalence and Risk Factors in Outpatients at Teda Health Center, Northwest Ethiopia: A Cross-Sectional Study

Background

Despite extensive efforts and achievements made in prevention and control, malaria is still a public health problem in Ethiopia. Currently, the case number has been climbing, even changing the epidemiology to the previously low-burden reporting locations. Therefore, our study is aimed at assessing malaria prevalence and associated risk factors in outpatients, Northwest Ethiopia.

Methods

A facility-based cross-sectional study was conducted among 318 malaria-suspected outpatients from October 22 to December 15, 2022, at Teda Health Center, Northwest Ethiopia. Sociodemographic characteristics and malaria risk factors were assessed by a face-to-face interview using a pretested questionnaire. Plasmodium parasites were detected by using microscopy on a blood film stained with 10% and 3% Giemsa stain. The data were analyzed using Statistical Package for Social Sciences software version 25, and statistical significance was reported at a p value < 0.05.

Results

Of the 318 study participants, 124 (39.0%; 95%CI = 33.6% - 44.6%) tested positive for Plasmodium infection. Plasmodium vivax, P. falciparum, and mixed infections were identified in 71 (57.3%), 47 (37.9%), and 6 (4.8%), respectively, among positive study participants. Individuals above the age of 15 (AOR = 2.704, 95% CI 1.370-5.336) were more likely to be infected with Plasmodium than under-five-year-old individuals. Rural residents (AOR = 2.56, 95% CI 1.281-5.098), those who sleep or work outside at night (AOR = 1.99, 95% CI 1.020-3.875), and individuals who did not use long-lasting insecticide-treated net (AOR = 3.26, 95% CI 1.633-6.499) and had a family member with a history of malaria (AOR = 2.902, 95%CI = 1.671 - 5.041) had higher odds of acquiring Plasmodium infection than their counterparts.

Conclusion

In our study area, malaria was a major health problem, with P. vivax being the dominant species. Multiple environmental and behavioural factors were associated with the infection acquisition. Therefore, urgent holistic intervention is required.

Current Status of Malaria Control and Elimination in Africa: Epidemiology, Diagnosis, Treatment, Progress and Challenges

The African continent carries the greatest malaria burden in the world. Falciparum malaria especially has long been the leading cause of death in Africa. Climate, economic factors, geographical location, human intervention and unstable security are factors influencing malaria transmission. Due to repeated infections and early interventions, the proportion of clinically atypical malaria or asymptomatic plasmodium carriers has increased significantly, which easily lead to misdiagnosis and missed diagnosis. African countries have made certain progress in malaria control and elimination, including rapid diagnosis of malaria, promotion of mosquito nets and insecticides, intermittent prophylactic treatment in high-risk groups, artemisinin based combination therapies, and the development of vaccines. Between 2000 and 2022, there has been a 40% decrease in malaria incidence and a 60% reduction in mortality rate in the WHO African Region. However, many challenges are emerging in the fight against malaria in Africa, such as climate change, poverty, substandard health services and coverage, increased outdoor transmission and the emergence of new vectors, and the growing threat of resistance to antimalarial drugs and insecticides. Joint prevention and treatment, identifying molecular determinants of resistance, new drug development, expanding seasonal malaria chemo-prevention intervention population, and promoting the vaccination of RTS, S/AS01 and R21/Matrix-M may help to solve the dilemma. China's experience in eliminating malaria is conducive to Africa's malaria prevention and control, and China-Africa cooperation needs to be constantly deepened and advanced. Our review aims to help the global public develop a comprehensive understanding of malaria in Africa, thereby contributing to malaria control and elimination.

Malaria Burden Stratification in Malawi- A report of a consultative workshop to inform the 2023-2030 Malawi Malaria Strategic Plan

Background: Malawi's National Malaria Control Programme (NMCP) is developing a new strategic plan for 2023-2030 to combat malaria and recognizes that a blanket approach to malaria interventions is no longer feasible. To inform this new strategy, the NMCP set up a task force comprising 18 members from various sectors, which convened a meeting to stratify the malaria burden in Malawi and recommend interventions for each stratum. Methods: The burden stratification workshop took place from November 29 to December 2, 2022, in Blantyre, Malawi, and collated essential data on malaria burden indicators, such as incidence, prevalence, and mortality. Workshop participants reviewed the malaria burden and intervention coverage data to describe the current status and identified the districts as a appropriate administrative level for stratification and action. Two scenarios were developed for the stratification, based on composites of three variables. Scenario 1 included incidence, prevalence, and under-five all-cause mortality, while Scenario 2 included total malaria cases, prevalence, and under-five all-cause mortality counts. The task force developed four burden strata (highest, high, moderate, and low) for each scenario, resulting in a final list of districts assigned to each stratum. Results: The task force concluded with 10 districts in the highest-burden stratum (Nkhotakota, Salima, Mchinji, Dowa, Ntchisi, Mwanza, Likoma, Lilongwe, Kasungu and Mangochi) 11 districts in the high burden stratum (Chitipa, Rumphi, Nkhata Bay, Dedza, Ntcheu, Neno, Thyolo, Nsanje, Zomba, Mzimba and Mulanje) and seven districts in the moderate burden stratum (Karonga, Chikwawa, Balaka, Machinga, Phalombe, Blantyre, and Chiradzulu). There were no districts in the low-burden stratum. Conclusion: The next steps for the NMCP are to review context-specific issues driving malaria transmission and recommend interventions for each stratum. Overall, this burden stratification workshop provides a critical foundation for developing a successful malaria strategic plan for Malawi.

Uptake of Plasmodium chabaudi hemozoin drives Kupffer cell death and fuels superinfections

Kupffer cells (KCs) are self-maintained tissue-resident macrophages that line liver sinusoids and play an important role on host defense. It has been demonstrated that upon infection or intense liver inflammation, KCs might be severely depleted and replaced by immature monocytic cells; however, the mechanisms of cell death and the alterations on liver immunity against infections deserves further investigation. We explored the impact of acute Plasmodium infection on KC biology and on the hepatic immune response against secondary infections. Similar to patients, infection with Plasmodium chabaudi induced acute liver damage as determined by serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) elevation. This was associated with accumulation of hemozoin, increased of proinflammatory response and impaired bacterial and viral clearance, which led to pathogen spread to other organs. In line with this, mice infected with Plasmodium had enhanced mortality during secondary infections, which was associated with increased production of mitochondrial superoxide, lipid peroxidation and increased free iron within KCs-hallmarks of cell death by ferroptosis. Therefore, we revealed that accumulation of iron with KCs, triggered by uptake of circulating hemozoin, is a novel mechanism of macrophage depletion and liver inflammation during malaria, providing novel insights on host susceptibility to secondary infections. Malaria can cause severe liver damage, along with depletion of liver macrophages, which can predispose individuals to secondary infections and enhance the chances of death.

Antiplasmodial Activity of 80% Methanolic Extract and Solvent Fractions of Stem Bark of Acacia tortilis in Swiss Albino Mice

Background

Malarial infection has significant negative impact on the health of the world population. It is treated by modern and traditional medicines. Among traditional medicinal plants, Acacia tortilis is used by different communities as antimalarial agent. Therefore, the objective of this study is to validate antimalarial activity of the stem bark of Acacia tortilis in mice.

Methods

To evaluate antimalarial activity of the plant, 4-day suppressive, curative, and prophylactic antimalarial test models were used. Parasitemia, packed cell volume (PCV), survival time, rectal temperature, and body weight were used to evaluate the effect of the plant extracts. Data were analyzed using SPSS version 26 followed by Tukey's post hoc multiple comparison test.

Results

The crude extract and dichloromethane fraction significantly suppressed the level of parasitemia (p < 0.001) and increased mean survival time (p < 0.01) at all tested doses. Similarly, significant effects were observed in mean survival time, % change of PCV, weight, and temperature in both curative and prophylactic antimalarial test models.

Conclusions

The methanolic extract and solvent fractions of the stem bark of Acacia tortilis has shown antimalarial activity, and the finding supports the traditional use and the in vitro studies. Thus, this study can be used as an initiation for researchers to find the most active phytochemical entity and to conduct additional safety and efficacy tests.

Deletion patterns, genetic variability and protein structure of pfhrp2 and pfhrp3: implications for malaria rapid diagnostic test in Amhara region, Ethiopia

Background

Although rapid diagnostic tests (RDTs) play a key role in malaria-control strategies, their efficacy has been threatened by deletion and genetic variability of the genes pfhrp2/3. This study aims to characterize the deletion, genetic patterns and diversity of these genes and their implication for malaria RDT effectiveness, as well as their genetic evolution in the Amhara region of Ethiopia.

Methods

The study included 354 isolates from symptomatic patients from the Amhara region of Ethiopia who tested positive by microscopy. Exon 1–2 and exon 2 of genes pfhrp2 and -3 were amplified, and exon 2 was sequenced to analyse the genetic diversity, phylogenetic relationship and epitope availability.

Results

The deletion frequency in exon 1–2 and exon 2 was 22 and 4.6% for pfhrp2, and 68 and 18% for pfhrp3, respectively. Double deletion frequency for pfhrp2 and pfhrp3 was 1.4%. High genetic diversity, lack of clustering by phylogenetic analysis and evidence of positive selection suggested a diversifying selection for both genes. The amino-acid sequences, classified into different haplotypes, varied widely in terms of frequency of repeats, with novel amino-acid changes. Aminoacidic repetition type 2 and type 7 were the most frequent in all the sequences. The most frequent epitopes among protein sequences were those recognized by MAbs 3A4 and C1-13.

Conclusion

Deletions and high amino acidic variation in pfhrp2 and pfhrp3 suggest their possible impact on RDT use in the Amhara region, and the high genetic diversity of these genes could be associated with a diversifying selection in Ethiopia. Surveillance of these genes is, therefore, essential to ensure the effectiveness of public health interventions in this region.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-022-04306-3.

Antimalarial Activity of Crude Extract and Solvent Fractions of Leaves of Solanum nigrum L. (Solanaceae) against Plasmodium berghei in Mice

Background. Current malaria treatment is associated with continued development of drug resistance. Thus, there is a need to develop safe and effective new treatments from different sources. Solanum nigrum L. (Solanaceae) is a plant used for the treatment of malaria in Ethiopian traditional medicine. This study was aimed at evaluating of antimalarial activity of the crude extract and fractions of S. nigrum L. (Solanaceae) leaves against P. berghei infection in mice. Method. Both prophylactic and suppressive models were used in evaluating antimalarial activity using the ANKA Plasmodium strain. In these models, male mice were randomly grouped into eleven groups (n = 5). Mice in group I were given 4% Tween-80, mice from group II up to X were given 100, 200, and 400 mg/kg of plant extract, and the last group (XI) was treated with chloroquine (25 mg/kg). Data were analyzed using one-way ANOVA followed by post hoc Tukey’s multiple comparison test. Results. Crude extract of leaves of S. nigrum showed chemosuppression of 30.68 ( $P<0.05$ ), 42.42 ( $P<0.01$ ), and 50.75% ( $P<0.001$ ) at 100, 200, and 400 mg/kg doses of the extract, respectively. At doses of 100, 200, and 400 mg/kg, the chloroform fraction produced a chemosuppressive effect of 40.15% ( $P<0.01$ ), 53.78% ( $P<0.001$ ), and 65.15% ( $P<0.001$ ) and a chemoprophylactic effect of 42.7% ( $P<0.05$ ), 51.84% ( $P<0.001$ ), and 67.17% ( $P<0.001$ ) when compared with negative control. In the suppressive model, the ethyl acetate fraction demonstrated a mean chemosuppression of 56.81% ( $P<0.001$ ), 65.9% ( $P<0.001$ ), and 70.83% ( $P<0.001$ ). Similarly, in the prophylactic model, the fraction showed suppression of 42.70% ( $P<0.05$ ), 53.11% ( $P<0.001$ ), and 71.03% ( $P<0.001$ ) at 100, 200, and 400 mg/kg doses. On the acute oral toxicity test, the extracts were safe at 2 g/kg dose. Conclusion. S. nigrum L. has antimalarial activity and supports the traditional medical practice.

Stratification at the health district level for targeting malaria control interventions in Mali

Malaria is the leading cause of morbidity and mortality in Mali. Between 2017 and 2020, the number of cases increased in the country, with 2,884,827 confirmed cases and 1454 reported deaths in 2020. We performed a malaria risk stratification at the health district level in Mali with a view to proposing targeted control interventions. Data on confirmed malaria cases were obtained from the District Health Information Software 2, data on malaria prevalence and mortality in children aged 6-59 months from the 2018 Demographic and Health Survey, entomological data from Malian research institutions working on malaria in the sentinel sites of the National Malaria Control Program (NMCP), and environmental data from the National Aeronautics and Space Administration. A stratification of malaria risk was performed. Targeted malaria control interventions were selected based on spatial heterogeneity of malaria incidence, malaria prevalence in children, vector resistance distribution, health facility usage, child mortality, and seasonality of transmission. These interventions were discussed with the NMCP and the different funding partners. In 2017-2019, median incidence across the 75 health districts was 129.34 cases per 1000 person-years (standard deviation = 86.48). Risk stratification identified 12 health districts in very low transmission areas, 19 in low transmission areas, 20 in moderate transmission areas, and 24 in high transmission areas. Low health facility usage and increased vector resistance were observed in high transmission areas. Eight intervention combinations were selected for implementation. Our work provides an updated risk stratification using advanced statistical methods to inform the targeting of malaria control interventions in Mali. This stratification can serve as a template for continuous malaria risk stratifications in Mali and other countries.

Epidemic malaria dynamics in Ethiopia: the role of self-limiting, poverty, HIV, climate change and human population growth

Background

During the last two decades, researchers have suggested that the changes of malaria cases in African highlands were driven by climate change. Recently, a study claimed that the malaria cases (Plasmodium falciparum) in Oromia (Ethiopia) were related to minimum temperature. Critics highlighted that other variables could be involved in the dynamics of the malaria. The literature mentions that beyond climate change, trends in malaria cases could be involved with HIV, human population size, poverty, investments in health control programmes, among others.

Methods

Population ecologists have developed a simple framework, which helps to explore the contributions of endogenous (density-dependent) and exogenous processes on population dynamics. Both processes may operate to determine the dynamic behaviour of a particular population through time. Briefly, density-dependent (endogenous process) occurs when the per capita population growth rate (R) is determined by the previous population size. An exogenous process occurs when some variable affects another but is not affected by the changes it causes. This study explores the dynamics of malaria cases (Plasmodium falciparum and Plasmodium vivax) in Oromia region in Ethiopia and explores the interaction between minimum temperature, HIV, poverty, human population size and social instability.

Results

The results support that malaria dynamics showed signs of a negative endogenous process between R and malaria infectious class, and a weak evidence to support the climate change hypothesis.

Conclusion

Poverty, HIV, population size could interact to force malaria models parameters explaining the dynamics malaria observed at Ethiopia from 1985 to 2007.

Prevalence and Associated Factors of Malaria Infection among Outpatients Visiting Shewa Robit Health Center, Northcentral Ethiopia

Introduction

Malaria infection is a serious health problem killing millions in tropical developing countries including Ethiopia. The present study focused on assessing malaria prevalence and identification of determinants in Shewa Robit, northcentral Ethiopia.

Methods

A cross-sectional study was conducted among 422 participants who visited Shewa Robit Health Center between 01/10/2017 and 30/04/2018, using a simple random sampling. Sociodemographic characteristics were recorded using a pre-tested semi-structured questionnaire and infection was confirmed by microscopic examination. Data were analyzed using the Statistical Program for Social Sciences (SPSS) version 20 and p < 0.05 was used to indicate the level of significance.

Results

Eighty-one (19.0%) microscopically confirmed malaria cases were recorded, P.vivax was the most frequently detected species (n = 58; 71.6%). Interestingly, 73.2% (n = 309) of the participant did not utilize LLINs due to the fear of toxicity (37.4%, n = 158), misconception (21.6%, n = 91), and shortage (14.2%, n = 60). The data showed age, gender, marital status, family size, usage of LLINs and application of IRS, proximity to mosquito breeding sites and less robust and porous walls were the determinants of the infection in the study area.

Conclusion

The prevalence of malaria in the study population was high and P. vivax being the most common causative agent. Environmental and behavioral factors related to LLIN are the potential determinants of malaria. Continued public health interventions, targeting proper utilization of bed nets, drainage of stagnant water, and improved public awareness about reducing the risk of insect bites have the potential to minimize the infection.

Five-Year Trend of Malaria Prevalence in Mojo Town, Central Ethiopia: Shifting Burden of the Disease and Its Implication for Malaria Elimination: A Retrospective Study

Introduction

Malaria continues to strike hardest against the health and economic development in Ethiopia. The peak of malaria incidence follows the main rainfall season in each year; however, its transmission tends to be highly heterogeneous within or between years and from area to area. Thus, this study was aimed to determine the trend prevalence of malaria in Mojo town, central Ethiopia.

Methods

A retrospective study was conducted in Mojo town, East Shoa zone, Ethiopia from February to March 2021. Malaria cases and related data documented between 2016 and 2020 were carefully reviewed from laboratory registration logbooks. The collected data were analyzed using descriptive statistics.

Results

A total of 19,106 blood films were examined from malaria-suspected patients. The overall microscopically confirmed prevalence of malaria was 4.2% (793/19,106). Plasmodium vivax was the predominant species accounting for 76.2% (604/793) of positive samples. Malaria cases declined from 259 in 2016 to 77 in 2020. The proportion of malaria was higher among males (64.8%, 514/793) than females (35.2%, 279/793) (P < 0.0001). Higher malaria cases were observed from the age group 15–24 years followed by the age group of 25–34 (P < 0.0001). The number of malaria cases was at a high level from September to November and lowest from December to February.

Conclusion

Despite a declining trend of malaria prevalence, it remains a public health burden in the area. P. vivax, the predominant species, should get attention during prevention and control strategies for the successful progress of the malaria elimination program.

Recent Advances in Understanding the Inflammatory Response in Malaria: A Review of the Dual Role of Cytokines

Malaria is a serious and, in some unfortunate cases, fatal disease caused by a parasite of the Plasmodium genus. It predominantly occurs in tropical areas where it is transmitted through the bite of an infected Anopheles mosquito. The pathogenesis of malaria is complex and incompletely elucidated. During blood-stage infection, in response to the presence of the parasite, the host's immune system produces proinflammatory cytokines including IL-6, IL-8, IFN-γ, and TNF, cytokines which play a pivotal role in controlling the growth of the parasite and its elimination. Regulatory cytokines such as transforming growth factor- (TGF-) β and IL-10 maintain the balance between the proinflammatory and anti-inflammatory responses. However, in many cases, cytokines have a double role. On the one hand, they contribute to parasitic clearance, and on the other, they are responsible for pathological changes encountered in malaria. Cytokine-modulating strategies may represent a promising modern approach in disease management. In this review, we discuss the host immune response in malaria, analyzing the latest studies on the roles of pro- and anti-inflammatory cytokines.

Plasmodium vivax epidemiology in Ethiopia 2000-2020: A systematic review and meta-analysis

BACKGROUND

Ethiopia is one of the scarce African countries where Plasmodium vivax and P. falciparum co-exist. There has been no attempt to derive a robust prevalence estimate of P. vivax in the country although a clear understanding of the epidemiology of this parasite is essential for informed decisions. This systematic review and meta-analysis, therefore, is aimed to synthesize the available evidences on the distribution of P. vivax infection by different locations/regions, study years, eco-epidemiological zones, and study settings in Ethiopia.

METHODS

This study was conducted in accordance with Preferred Reposting Items for Systematic Reviews and Meta Analyses (PRISMA) guidelines. Studies conducted and published over the last two decades (2000 to 2020) that reported an estimate of P. vivax prevalence in Ethiopia were included. The Cochrane Q (χ2) and the I2 tests were used to assess heterogeneity, and the funnel plot and Egger's test were used to examine publication bias. A p-value of the χ2 test <0.05 and an I2 value >75% were considered presence of considerable heterogeneity. Random effect models were used to obtain pooled estimate of P. vivax infection prevalence. This study is registered with PROSPERO (International Prospective Register of Systematic Reviews): ID CRD42020201761.

RESULTS

We screened 4,932 records and included 79 studies that enrolled 1,676,659 confirmed malaria cases, from which 548,214 (32.69%) were P. vivax infections and 1,116,581 (66.59%) were due to P. falciparum. The rest were due to mixed infections. The pooled estimate of P. vivax prevalence rate was 8.93% (95% CI: 7.98-9.88%) with significant heterogeneity (I2 = 100%, p<0.0001). Regional differences showed significant effects (p<0.0001, and I2 = 99.4%) on the pooled prevalence of P. vivax, while study years (before and after the scaling up of interventional activities) did not show significant differences (p = 0.9, I2 = 0%). Eco-epidemiological zones considered in the analysis did show a significant statistical effect (p<0.001, I2 = 78.5%) on the overall pooled estimate prevalence. Also, the study setting showed significant differences (p = 0.001, and I2 = 90.3%) on the overall prevalence, where significant reduction of P. vivax prevalence (4.67%, 95%CI: 1.41-7.93%, p<0.0001) was observed in studies conducted at the community level. The studies included in the review demonstrated lack of publication bias qualitatively (symmetrical funnel plot) and quantitatively [Egger's test (coefficient) = -2.97, 95% CI: -15.06-9.13, p = 0.62].

CONCLUSION

The estimated prevalence of P. vivax malaria in Ethiopia was 8.93% with P. vivax prevailing in the central west region of Ethiopia, but steadily extending to the western part of the country. Its distribution across the nation varies according to geographical location, study setting and study years.

Evaluation of Antimalarial Activity of 80% Methanolic Root Extract of Dorstenia barnimiana Against Plasmodium berghei-Infected Mice

BACKGROUND

Due to resistance of parasites, costs, and safety issues with currently available drugs, there is a need to discover new antimalarials. Medicinal plants are one of the most important sources of new drugs. The purpose of this study was to evaluate the antimalarial activity of a methanolic root extract of Dorstenia barnimiana in Swiss albino mice infected with Plasmodium berghei.

METHODS

Four-day suppressive, curative, and prophylactic tests were performed on mice infected with P. berghei to evaluate the antimalarial activity of a methanolic root extract of the plant. Parasitemia suppression, survival time, body-weight change, rectal temperature change, and packed-cell volume were used to evaluate the activity of the extract. Data were analyzed using one-way ANOVA followed by Tukey's post hoc test for comparisons between and within groups, with P<0.05 considered statistically significant.

RESULTS

The D. barnimiana root extract showed significant (P<0.01) parasitemia-suppressive activities in all models compared to the negative control. The extract increased mean survival time and prevented weight loss, reduction in temperature, and anemia significantly in all tested doses in 4-day suppressive and curative tests.

CONCLUSION

Based on these findings, D. barnimiana root has promising antimalarial activity and can considered a potential source to develop new agents.

Current Epidemiological Characteristics of Imported Malaria, Vector Control Status and Malaria Elimination Prospects in the Gulf Cooperation Council (GCC) Countries

Malaria is the most common vector-borne parasitic infection causing significant human morbidity and mortality in nearly 90 tropical/sub-tropical countries worldwide. Significant differences exist in the incidence of malaria cases, dominant Plasmodium species, drug-resistant strains and mortality rates in different countries. Six Gulf Cooperation Council (GCC) countries (Bahrain, Kuwait, Qatar, Oman, Saudi Arabia and United Arab Emirates, UAE) in the Middle East region with similar climates, population demographics and economic prosperity are aiming to achieve malaria elimination. In this narrative review, all studies indexed in PubMed describing epidemiological characteristics of indigenous and imported malaria cases, vector control status and how malaria infections can be controlled to achieve malaria elimination in GCC countries were reviewed and discussed. These studies have shown that indigenous malaria cases are absent in Bahrain, Kuwait, Qatar and UAE and have progressively declined in Oman and Saudi Arabia. However, imported malaria cases continue to occur as GCC countries have large expatriate populations originating from malaria-endemic countries. Various malaria control and prevention strategies adopted by GCC countries including more stringent measures to reduce the likelihood of importing malaria cases by prior screening of newly arriving expatriates and vector elimination programs are likely to lead to malaria elimination in this region.

An evaluation of repellency and feeding inhibition of ethno-medicinal plants against major malaria vectors in southern Ethiopia

Background

Plant-based mosquito control methods may use as a supplementary malaria vector control strategy. This study aimed to evaluate the effect of smoking ethno-medicinal plants on indoor density and feeding activity of malaria vectors at early hours of the night and its residual effect after midnight in southern Ethiopia.

Methods

Both field and tent trials were conducted to evaluate the impact of smoking Juniperus procera leaves, Eucalyptus globulus seeds and Olea europaea leaves in Kolla Shara Village from July 2016 to February 2017. For the field trial, five grass-thatched traditional huts (three for ethno-medicinal plants and two as control [only charcoal smoking and non-charcoal smoking]) were used. Indoor host-seeking mosquitoes were collected by CDC light traps. A Latin square design was employed to minimize the bias due to the variation in house location and different sampling nights. For the tent experiment, 25 3–5-day-old starved wild female Anopheles mosquitoes reared from the larvae were released into the tents where a calf was tethered at the mid-point of each tent.

Results

A total of 614 Anopheles mosquitoes belonging to 5 species were collected from 5 huts, of which 93.4% was An. arabiensis; O. europaea, E. globulus and J. procera reduced the indoor density of An. arabiensis, with the mean percentage drop of 80%, 73% and 70%, respectively. In the tent trial, smoking of these plants had significant knockdown effects and inhibited feeding on the calves (F = 383.5, DF = 3, P < 0.01). The mean knockdown effect due to O. europaea was relatively high (17.7 ± 0.54; 95% CI 16.8–18.6), while it was only 0.9 ± 0.1 (95% CI 0.29–1.52) in the control tents. All the test plants used in the tent trial caused significantly inhibited feeding activity of An. arabiensis on the host (F = 383.5, DF = 3, P < 0.01). About 94.5%, 89.5% and 86% of mosquitoes were unfed because of the smoking effect of O. europaea, E. globulus and J. procera, respectively, whereas only 19.5% were unfed in the control tent.

Conclusions

Smoking ethno-medicinal plant materials reduced indoor density of malaria vectors and inhibited feeding on calves inside the tents. Thus, plant-based mosquito control methods may play a vital role in reducing mosquito bites in the early hours of the night and thereby reduce residual malaria transmission.

Current Status and the Epidemiology of Malaria in the Middle East Region and Beyond

Vector-borne parasitic infectious diseases are important causes of morbidity and mortality globally. Malaria is one of the most common vector-borne parasitic infection and is caused by five Plasmodium species, namely P. falciparum, P. vivax, P. ovale, P. malariae, and P. knowlesi. Epidemiologically, differences in the patterns of malaria cases, causative agent, disease severity, antimicrobial resistance, and mortality exist across diverse geographical regions. The world witnessed 229 million malaria cases which resulted in 409,000 deaths in 2019 alone. Although malaria cases are reported from 87 countries globally, Africa bears the brunt of these infections and deaths as nearly 94% of total malaria cases and deaths occur in this continent, particularly in sub-Saharan Africa. Most of the Middle East Region countries are malaria-free as no indigenous cases of infection have been described in recent years. However, imported cases of malaria continue to occur as some of these countries. Indeed, the six Gulf Cooperation Council (GCC) countries have large expatriate population originating from malaria endemic countries. In this review, the current status and epidemiology of malaria in the Middle East Region countries and other malaria-endemic countries that are home to a large migrant workforce being employed in Middle East Region countries are discussed.