Tropical Medicine and Health最新文献

Background: Plasmodium falciparum (P. falciparum) remains a significant public health challenge globally, especially in sub-Saharan Africa (SSA), where it accounts for 99% of all malaria infections. The outcomes of P. falciparum infection vary, ranging from asymptomatic to severe, and are associated with factors such as host immunity, parasite genetic diversity, and multiplicity of infection (MOI). Using seven neutral microsatellite markers, the current study investigated P. falciparum genetic diversity and MOI in both asymptomatic and symptomatic malaria individuals in Uganda.

Methods: This cross-sectional study analyzed 225 P. falciparum isolates from both asymptomatic and symptomatic malaria patients, ranging in age from 6 months to ≥ 18 years. P. falciparum genetic diversity, MOI, and multi-locus linkage disequilibrium (LD) were assessed through genotyping of seven neutral microsatellite markers: Poly-α, TA1, TA109, PfPK2, 2490, C2M34-313, and C3M69-383. Genetic data analysis was performed using appropriate genetic analysis software.

Results: P. falciparum infections exhibited high genetic diversity in both asymptomatic and symptomatic individuals. The mean expected heterozygosity (He) ranged from 0.79 in symptomatic uncomplicated malaria cases to 0.81 in asymptomatic individuals. There was no significant difference (p = 0.33) in MOI between individuals with asymptomatic and symptomatic infections, with the mean MOI ranging from 1.92 in symptomatic complicated cases to 2.10 in asymptomatic individuals. Polyclonal infections were prevalent, varying from 58.5% in symptomatic complicated malaria to 63% in symptomatic uncomplicated malaria cases. A significant linkage disequilibrium (LD) was observed between asymptomatic and symptomatic uncomplicated/complicated infections (p < 0.01). Genetic differentiation was low, with F_ST values ranging from 0.0034 to 0.0105 among P. falciparum parasite populations in asymptomatic and symptomatic uncomplicated/complicated infections.

Conclusion: There is a high level of P. falciparum genetic diversity and MOI among both symptomatic and asymptomatic individuals in Uganda. Asymptomatic carriers harbor a diverse range of parasites, which poses challenges for malaria control and necessitates targeted interventions to develop effective strategies.

Background: The primary strategy for achieving the second goal of the Global Program to Eliminate Lymphatic Filariasis (GPELF) is morbidity management and disability prevention (MMDP), aimed at alleviating the suffering of affected populations. A significant challenge in many LF-endemic areas is the effective registration and identification of individuals with LF, which is crucial for planning and ensuring access to MMDP services. This study seeks to map the geographical distribution of LF-related morbidities across 24 endemic districts in Ethiopia.

Methods: A community-based cross-sectional study was conducted to identify individuals affected by LF in 24 endemic districts using primary health care units (PHCUs). The study involved 946 trained health extension workers (HEWs) conducting house-to-house visits to identify and register cases of lymphedema and hydrocele, with support from 77 trained supervisors and 87 team leaders coordinating the morbidity mapping. Certified surgeons performed confirmatory evaluations through clinical assessments on a randomly selected sample of cases to validate HEW diagnoses, ensuring accurate identification of lymphedema and hydrocele. Statistical analysis of the data, including the severity of lymphedema and acute attacks, was conducted using STATA 17.

Results: This study involved 300,000 households with nearly 1.2 million individuals, leading to the identification of 15,527 LF cases-14,946 (96.3%) with limb lymphedema and 581 (3.7%) with hydrocele. Among those with lymphedema, 8396 (54.1%) were women. Additionally, 13,731 (88.4%) patients resided in rural areas. Of the 14,591 cases whose acute attack information was recorded, 10,710 (73.4%) reported experiencing at least one acute attack related to their lymphedema in the past 6 months, with a notable percentage of males (74.5%; n = 4981/6686). Among the 12,680 recorded cases of leg lymphedema, the percentage of acute attacks increased with severity: 64% (n = 5618) mild cases, 68% (n = 5169) moderate cases and 70% (n = 1893) severe cases.

Conclusion: This study successfully mapped the geographical distribution of LF morbidities across 24 LF-endemic districts in Ethiopia, identifying a substantial number of lymphedema and hydrocele cases, particularly in rural areas where healthcare access is limited. The findings underscore the potential of Ethiopia's health extension program to identify affected individuals and ensure they receive necessary care. The findings inform targeted interventions and access to MMDP services, contributing to Ethiopia's goal of eliminating LF by 2027.

Background: Diagnosis and treatment initiation delays for tuberculosis (TB) are significant challenges in resource-limited settings. These delays can result in poor treatment outcomes, disease transmission, and increased costs. This study aimed to assess the effect of integrating traditional care with modern healthcare systems on reducing TB diagnosis delay.

Methods: A cluster randomized controlled trial was conducted among TB patients, with 510 participants, 255 individuals were assigned to the intervention group and 255 to the control group. Training in the intervention group was provided for both traditional and modern healthcare providers in three rounds to enhance their knowledge, attitudes, and skills in TB screening and referral. A non-parametric independent sample test was used to compare the baseline and end-line data. The effect size was determined using Cohen's d. To account for individual and cluster-level variations, a mixed-effect parametric survival model was employed. Furthermore, conditional (fixed only) and marginal (random effects) graphs were used to compare between the intervention and control groups.

Results: A total of 510 participants were included in the baseline study, with a similar number of participants included in the endline study. In the intervention group, the delay in diagnosis was 4.185 per 1000 person-days post-intervention, compared to 4.608 per 1000 person-days pre-intervention. In the control group, the delay for diagnosis was 4.759 per 1000 person-days pre-intervention and 5.031 per 1000 person-days post-intervention. The median time to diagnosis was 135 days. The non-parametric comparison showed that the intervention significantly reduced patient delays in the intervention group compared to the control group (p = 0.006), with a Cohen's d effect size of 0.246. The intervention also significantly reduced diagnosis delay in the intervention group compared to the control group (p = 0.036), with a Cohen's d effect size of 0.187. The diagnosis of TB was accelerated by 1.076 times due to the integration of traditional care with the modern healthcare system in the intervention group compared to the control group (δ: 1.076; 95% CI 1.021, 1.134).

Conclusions: The involvement of traditional care providers in TB control programs significantly reduced diagnosis delays in Ethiopia. These findings suggest the need for integrating traditional care with modern healthcare systems for the effective prevention of TB in high-burden countries. Clinical trial registration ClinicalTrials.gov ID: NCT05236452.

Background: The emergence of multidrug resistant Candida species to available drugs has led to renewed interest in the use of herbal medicines globally. This study scientifically verified antifungal effectiveness of five commonly used plant species in Pader district, against selected pathogenic candida strains.

Methods: Powdered roots of Momordica foetida, Sansevieria dawei and Distimake dissectus; and stem barks of Khaya anthotheca and Mitragyna rubrostipulata were extracted sequentially using petroleum ether and methanol, respectively; and total water extraction at 24.4 °C (maceration), 60 °C (decoction) and boiling water at 87 °C (hot water infusion). Extracts and their combinations, positive controls (amphotericin B, and fluconazole) and negative control (80% dimethyl sulfoxide, verified to be tolerable concentration to the tested Candida species) were screened and verified for their antifungal activity against Candida albicans (ATCC: American Type Culture Collection reference strain 10231, ATCC 90028, 0770a and 0796), C. glabrata (VVc 004, ATCC 2950) and C. tropicalis (ATCC 750 and 0210) using agar well diffusion and broth micro-dilution, respectively.

Results: Aqueous extract (24.4 °C) of M. rubrostipulata (ZOI: 18.00 ± 1.00 to 38.33 ± 0.17; MIC: 3.13 ± 0.00 to 20.83 ± 4.17; MFC: 12.50 ± 0.00 to 200.00 ± 0.00), methanol extract of K. anthotheca (10.11 ± 0.31 to 15.11 ± 0.65; 1.04 ± 0.26 to 12.50 ± 0.00; 12.50 ± 0.00 to 100.00 ± 0.00), and combination of aqueous extract (60 °C) of D. dissectus + methanol extract of K. anthotheca (7.89 ± 0.26 to 19.67 ± 0.37; 0.78 ± 0.00 to 50.00 ± 0.00; 12.50 ± 0.00 to 200.00 ± 0.00) exhibited broad spectrum antifungal activities and were fungistatic against all tested Candida species, which comprised 8 clinical/control and susceptible/resistant strains. None of the conventional drugs used demonstrated broad spectrum antifungal activity across all tested Candida species/strains.

Conclusion: Methanol extract of K. anthotheca, aqueous extract (24.4 °C) of M. rubrostipulata, and combination of aqueous extract (60 °C) of D. dissectus + methanol extract of K. anthotheca could be effective in the treatment of candidiasis. They demonstrated potential broad spectrum antifungal activity against different species and strains of tested Candida than the fluconazole and amphotericin B drugs. Their fungistatic nature showed their ability to inhibit fungal growth. Hence, these extracts/extract combination can offer better treatment option for candidiasis if they are standardized and also their active curative compounds isolated and made into antifungal drugs.

Background: Since 2012, the World Health Organization has recommended seasonal malaria chemoprevention (SMC) with sulfadoxine-pyrimethamine plus amodiaquine (SPAQ) for children aged 3-⁠59 months in regions where malaria transmission is seasonal. Full ingestion of SMC medicines without spitting or vomiting during a complete 3-day course is critical to ensure effectiveness of SMC medicines and to avoid development of antimalarial resistance. Although evidence suggests that spitting or vomiting is not rare, there is limited analytical evidence on potential factors associated with spitting or vomiting in SMC campaigns.

Methods: We utilized data from SMC coverage surveys conducted in Burkina Faso, Chad, Togo and Nigeria between 2020 and 2022. Episodes of spitting or vomiting were defined as SMC-eligible children spitting out most of the dose or vomiting the entire dose within 30 min of SPAQ administration as reported by primary caregivers. We conducted a cross-sectional study using mixed-effects logistic regression with variables including household socioeconomic variables and caregiver knowledge of SMC, to identify factors associated with spitting or vomiting.

Results: The proportion of SMC-eligible children spitting or vomiting SPAQ doses ranged from 1.81% in Nigeria to 4.36% in Chad. The odds of spitting or vomiting were lower among children administered medicines under community distributor (CD) supervision, and whose primary caregivers had a high degree of knowledge of SMC. Spitting or vomiting were negatively associated with caregiver adherence to AQ administration and caregiver reporting of children's adverse reactions to SMC medicines. Over half of the children experiencing a spitting or vomiting episode did not receive a replacement dose from CDs. Redosing was positively associated with caregiver educational attainment, caregiver knowledge of SMC, and directly supervised medicine administration.

Conclusions: CD-supervised administration of SPAQ can strengthen community engagement strategies to enhance appropriate administration and full ingestion of SMC medicines according to the SMC delivery protocol.

Background: After three years with no local transmission of malaria, an outbreak occurred in Iran in 2022. Key malaria control methods in Iran are including indoor residual spraying (IRS), long-lasting insecticide-treated nets (LLINs), and prompt diagnosis and treatment of malaria cases. Anopheles sacharovi is one of the main malaria vectors in Iran. This study aimed to determine the insecticides resistance status of An. sacharovi in northwestern Iran, to inform effective vector control programs in this region.

Methods: Larval stages of An. sacharovi were collected from various larval habitats located in the villages along the Aras River. Adult susceptibility tests were performed on An. sacharovi using diagnostic doses of insecticides accordance to World Health Organization (WHO) guidelines. The study also evaluated agricultural insecticide and fertilizer usage alongside the presence of natural mosquito predators in breeding sites in the study area.

Results: Alongside various chemicals such as silica, humic acid, superphosphate, sulfur, urea, and solupotasse at different dose levels, organophosphorus and pyrethroid insecticides are commonly used in rice fields and orchards. Anopheles sacharovi displayed diverse reactions to insecticides, demonstrating resistance to DDT but sensitivity to malathion, and showing similar reactions to carbamate and pyrethroid insecticides.

Conclusions: These results provide significant insights into agricultural practices and the presence of mosquito larvae in the study area. The extensive use of a specific herbicide illustrates its popularity among farmers for weed control, while other agricultural products focus on enhancing soil fertility and productivity. The absence of mosquito larvae in habitats with predators indicates the usefulness of these predators in controlling the population of mosquitoes. The resistance of mosquitoes to certain insecticides highlights the need for careful selection and intermittent use of insecticides in vector control programs. These findings can inform the development of targeted strategies to reduce malaria transmission risks. Further research is essential for assessing the effectiveness of these interventions.

Hepatitis B virus (HBV) poses a significant public health threat, particularly in developing countries with high endemicity but poor vaccination among healthcare workers (HCWs). Needlestick injuries increase HCWs' risk, yet only about 42% of HCWs are fully vaccinated compared to 97% in high-income countries. Challenges to vaccine uptake include availability, demanding schedules with frequent unit rotations hindering access, high cost of acquiring shots, and stock shortages resulting in missed opportunities. Mandatory, cost-free HBV vaccinations for HCWs, supported by legislation, international aid, and digital reminders, could ensure self-protection and safety while contributing to the global objective of eradicating HBV by 2030.

Background: Intestinal worm infections are a significant public health concern for pregnant women in low- and middle-income countries. These infections can lead to anaemia, malnutrition, and adverse pregnancy outcomes, including premature birth and low birth weight. Deworming medication during pregnancy is a safe and effective strategy to prevent these complications and improve maternal and child health. This study aims to investigate the trends and inequalities in the use of deworming medication during pregnancy among women in Sierra Leone between 2008 and 2019.

Methods: The study utilised data from the Sierra Leone Demographic Health Surveys conducted in 2008, 2013, and 2019. We used the Health Equity Assessment Toolkit developed by the World Health Organisation to calculate various measures of inequality, including difference, ratio, population attributable risk, and population attributable fraction. An inequality assessment was conducted for five stratifiers: age, economic status, level of education, place of residence, and sub-national province.

Results: The prevalence of deworming medication during pregnancy was 43.8% in 2008, 72.4% in 2013, and 83.5% in 2019 in Sierra Leone. There was a decrease in age-related inequality from a difference of 3.7% in 2008 to -0.8% in 2019. Economic-related inequality increased from a difference of -8.5% in 2008 to -8.2% in 2019. Both population attributable fraction and population attributable risk were zero in all survey years for economic status, indicating no improvement in the setting average without economic-related inequality. Inequality in education increased from a difference of -8.9% in 2008 to -8.4% in 2019 and decreased from a difference of -2.6% in 2008 to -5.5% in 2019 for place of residence. Provincial inequality decreased from a difference of 29.5% in 2008 to 11.8% in 2019. The population attributable risk for province reveals that the setting average could have been 10.5 percentage points lower in 2008, 8.2 percentage points lower in 2013, and 5.9 percentage points lower in 2019 without provincial inequality.

Conclusion: The prevalence of deworming medication use during pregnancy substantially increased from 2008 to 2019 (43.8% to 83.5%) in Sierra Leone. This suggests a positive public health trend in maternal healthcare access and education. Inequalities related to economic status and education increased slightly while age-related, place of residence and provincial inequalities decreased. This indicates an inequitable distribution of this essential healthcare intervention across these stratifiers. The government and policymakers should continue efforts to raise awareness and promote the use of deworming medication during pregnancy.

The study by Mwatenga et al. found a tuberculosis (TB) prevalence of 10.2% and an HIV prevalence of 19.1% among inmates, with all TB cases co-infected with HIV. Education level, smoking history, and substance use are key predictors of coinfections. Although informative, its single-centred design and reliance on sputum samples may be insufficient for some patient groups, potentially compromising diagnostic accuracy. Expanding the study to include several jails and employing more diagnostic procedures may increase reliability and the ability to generalize. The report also notes the lack of debate on broader socioeconomic variables and structural barriers to healthcare in jails, which are crucial to understanding inmates' health challenges. Overcrowding, malnutrition, and a poor healthcare system are examples of environmental factors that probably contribute to the spread of tuberculosis and make managing HIV more difficult. Additionally, not enough is known about the dietary habits of prisoners and other health conditions like diabetes or mental health, which may have an impact on the course of HIV and TB. Future studies should take these extra characteristics into account to create more comprehensive approaches to controlling HIV coinfections and TB in prison populations. This will help build more effective therapies.