Trop. Med. Infect. Dis., Volume 9, Issue 4 (April 2024) – 25 articles

The zoonotic visceral leishmaniasis is caused by the protozoan Leishmania infantum and dogs are reservoirs for this parasite. For the diagnosis of Leishmania at the species level in dogs in formalin-fixed, paraffin-embedded skin (FFPES) samples, colorimetric in situ hybridization (CISH) and quantitative real-time polymerase chain reaction (qPCR) are options, but their sensitivities are not well established. Therefore, the aim of this study was to determine the sensitivity of these two techniques in FFPES for the diagnosis of the L. infantum infection in dogs using culture as the reference standard. The FFPES of 48 dogs with cutaneous infection by L. infantum confirmed by culture and by multilocus enzyme electrophoresis were examined by CISH and qPCR using specific probes for L. infantum. The sensitivities of qPCR, CISH and their combination were, respectively, 77.0%, 58.0% and 83.3%. The sensitivities of qPCR in dogs with and without clinical signs were, respectively, 74.2% and 82.4%. The sensitivities of CISH in dogs with and without clinical signs were, respectively, 61.3% and 52.9%. The CISH and qPCR showed satisfactory sensitivities for the diagnosis of L. infantum in the FFPES of dogs, even in dogs without clinical signs, and their combination increases the sensitivity for this diagnosis. Full article

Despite ongoing efforts for elimination, malaria continues to be a major public health problem in the Republic of Panama. For effective elimination, it is key that malaria foci and areas of high transmission are identified in a timely manner. Here, we study malaria transmission records for the 2015–2022 period, a time when cases have increased by a factor of ten. Using several methods to study spatial and spatiotemporal malaria confirmed case clusters at the level of localities, including LISA and scan, we found that cases are clustered across indigenous villages located within the autonomous indigenous regions of Ngäbe–Buglé, Guna Yala, and Embera, with the latter on the eastern border of Panama (with Colombia). We discuss the different factors that might be shaping the marked increase in malaria transmission associated with these clusters, which include an inflow of malaria-exposed migrating populations hoping to reach the USA, insufficient health services, and the lack of culturally sensitive actionable tools to reduce malaria exposure among the ethnically diverse and impoverished indigenous populations of Panama. Full article

Tuberculosis (TB) is a disease caused by the bacillus Mycobacterium tuberculosis (MTB). Human immunodeficiency virus (HIV) infection and type 2 diabetes mellitus (T2DM) are among the main risk factors for the development of TB and increase the risk of drug-resistant TB developing (DR-TB). The aim of this study was to estimate the prevalence of DR-TB in patients with HIV or T2DM in Sinaloa, Mexico. This was an observational and cross-sectional study. The analysis was conducted using the clinical data of patients registered on the National Epidemiological Surveillance System for TB (SINAVE/PUI-TB) platform with a presumed diagnosis of TB during 2019 to 2021 in Sinaloa, Mexico. The prevalence of DR-TB was estimated in HIV and T2DM patients, as well as the odds ratios for their sociodemographic variables, using the Chi-square test. There were 2, 4, and 4 TB-HIV cases and 2, 6, and 9 TB-T2DM cases during 2019, 2020, and 2021, respectively, whereas there were 2 and 1 DRTB-HIV and DRTB-T2DM cases, respectively. The results indicated that the WHO guidelines for DR-TB were not properly applied to this high-risk population. Hence, the appropriate application of guidelines for TB and DR-TB detection in these patients needs to be immediately implemented by the State health system. Full article

Echinococcosis, especially alveolar echinococcosis (AE), is becoming an emerging/re-emerging disease with a growing number of cases reported globally. The diagnosis of echinococcosis is based mainly on imaging, which may be challenging when the image presentation is atypical. We reported one patient with suspected cystic echinococcosis (CE) by imaging. The cell-free DNA (cfDNA) obtained from sequencing the patient’s plasma before the operation showed that this patient probably had AE with 45 reads mapped to the Echinococcus multilocularis reference genome (Read-Pairs Per Million = 0.24). The patients underwent surgery, and the pathological result showed that the patient had AE. The conventional polymerase chain reaction (PCR) of her lesion sample extraction also indicated that the infection was caused by Echinococcus multilocularis. The follow-up ultrasound after three months indicated no recurrence. We demonstrated that the differentiation of CE and AE by imaging may not be that easy, with further elaboration on the differentiation between AE and CE in different aspects. We demonstrated that it is possible to use patients’ plasma cfDNA mapped to Echinococcus references before the operation to obtain the objective clue of the lesion to facilitate diagnosis. Full article

Background: Cystic echinococcosis (CE) is a neglected tropical parasitic disease that poses huge disease, social and economic burdens worldwide; however, there has been little knowledge on the global morbidity, mortality and disability-adjusted life years (DALYs) of CE until now. This study aimed to collect the most up-to-date data about the global, regional and national disease burden due to CE from 1990 to 2019 and to project trends in the next 10 years. Methods: We measured the global, regional and national morbidity, mortality and DALYs of CE from 1990 to 2019 based on the Global Burden of Disease Study 2019 (GBD 2019) data, and we examined the correlation between socioeconomic development levels and the disease burden of CE. In addition, the disease burden due to CE was projected from 2020 to 2030. Results: The age-standardized incidence rate (ASIR) of CE reduced from 2.65/10⁵ [95% UI: (1.87/10⁵ to 3.7/10⁵)] in 1990 to 2.6/10⁵ [95% UI: (1.72/10⁵ to 3.79/10⁵)] in 2019 (EAPC = −0.18%). The number of deaths, DALYs, age-standardized mortality rate (ASMR) and age-standardized DALY rate due to CE all showed a tendency to decline from 1990 to 2019. A higher disease burden of CE was measured in women than in men in 2019. There was a significant difference in the ASMR of CE by region according to the socio-demographic index (SDI), and lower burdens of CE were estimated in high-SDI regions. The global ASIR of CE is projected to decline from 2020 to 2030; however, the ASMR and age-standardized DALY rate are projected to rise. Conclusions: The global burden of CE remains high, and it is recommended that more health resources are allocated to low-SDI regions, women and the elderly aged 55 to 65 years to reduce the disease burden of CE. Full article

Background: Infective endocarditis (IE) is a serious condition which is difficult to diagnose and to treat, both medically and surgically. Objectives: The objective of this study was to evaluate the impact of the SARS-CoV-2 pandemic on the management of patients with IE. Methods: We conducted a single-centre retrospective study including patients hospitalized for IE during the pandemic (Group 2) compared with the same period the year before (Group 1). We compared clinical, laboratory, imagery, therapeutic, and patient outcomes between the two groups. Results: A total of 283 patients were managed for possible or definite IE (164 in Group 1 and 119 in Group 2). There were more intravenous drug-related IE patients in Group 2 (p = 0.009). There was no significant difference in surgery including intra-cardiac device extraction (p = 0.412) or time to surgery (p = 0.894). The one-year mortality was similar in both groups (16% versus 17.7%, p = 0.704). The recurrence rate was not significantly different between the two groups (5.9% in Group 2 versus 9.1% in Group 1, p = 0.311). Conclusions: The SARS-CoV-2 pandemic did not appear to have had a negative impact on the management of patients with IE. Maintenance of the activities of the endocarditis team within the referral centre probably contributed to this result. Nevertheless, the high proportion of intravenous drug-addicted patients in the pandemic cohort suggests that the SARS-CoV-2 pandemic had a major psychosocial impact. Full article

Glutathione transferases (GSTs EC 2.5.1.18) are critical components of phase II metabolism, instrumental in xenobiotics’ metabolism. Their primary function involves conjugating glutathione to both endogenous and exogenous toxic compounds, which increases their solubility and enables their ejection from cells. They also play a role in the transport of non-substrate compounds and immunomodulation, aiding in parasite establishment within its host. The cytosolic GST subfamily is the most abundant and diverse in helminths, and sigma-class GST (GSTσ) belongs to it. This review focuses on three key functions of GSTσ: serving as a detoxifying agent that provides drug resistance, functioning as an immune system modulator through its involvement in prostaglandins synthesis, and acting as a vaccine antigen. Full article

The mosquito microbiota is a critical determinant of mosquito life history. It is therefore a target for novel vector control strategies like paratransgenesis. However, the microbiota in Anopheles funestus, a major African malaria vector, is poorly characterized. Thus, the study aimed to investigate the overall bacterial landscape in the salivary glands, ovaries and midguts of three laboratory strains of An. funestus differing in insecticide-resistant phenotype by sequencing the V3–V4 hypervariable region of bacterial 16S rRNA genes. When examining alpha diversity, the salivary glands harbored significantly more bacteria in terms of species richness and evenness compared to ovaries and midguts. On the strain level, the insecticide-susceptible FANG strain had significantly lower bacterial diversity than the insecticide-resistant FUMOZ and FUMOZ-R strains. When looking at beta diversity, the compositions of microbiota between the three tissues as well as between the strains were statistically different. While there were common bacteria across all three tissues and strains of interest, each tissue and strain did exhibit differentially abundant bacterial genera. However, overall, the top five most abundant genera across all tissues and strains were Elizabethkingia, Acinetobacter, Aeromonas, Cedecea and Yersinia. The presence of shared microbiota suggests a core microbiota that could be exploited for paratransgenesis efforts. Full article

Infective endocarditis (IE) is characterised by fever, heart murmurs, and emboli. Splenic emboli are frequent in left-sided IE. A systematic review of the literature published on splenic embolism (SE) between 2000 and 2023 was conducted. Search strategies in electronic databases identified 2751 studies published between 1 January 2000 and 4 October 2023, of which 29 were finally included. The results showed that the imaging tests predominantly used to detect embolisms were computed tomography (CT), magnetic resonance imaging, positron emission tomography (PET)/CT, single-photon emission computed tomography/CT, ultrasound, and contrast-enhanced ultrasound. More recent studies typically used ¹⁸F-FDG PET-CT. The proportion of SE ranged from 1.4% to 71.7%. Only seven studies performed systematic conventional CT screening for intra-abdominal emboli, and the weighted mean frequency of SE was 22% (range: 8–34.8%). ¹⁸F-FDG PET-CT was performed systematically in seven studies, and splenic uptake was found in a weighted mean of 4.5%. There was a lack of uniformity in the published literature regarding the frequency and management of splenic embolisation. CT scans were the most frequently used method, until recently, when ¹⁸F-FDG PET-CT scans began to predominate. More data are necessary regarding the frequency of SE, especially focusing on their impact on IE management and prognosis. Full article

Background: International migration is a global phenomenon with significant implications on the health–disease process due to exposures along transit routes and local/destination epidemiological indicators. We aimed to analyze the transmission and spread of tuberculosis among international migrants and refugees from a spatiotemporal perspective and the associated factors. Method: This was an ecological study of cases of tuberculosis in international migrants in Brazil, between 2010 and 2021. Annual incidence rates were calculated and spatiotemporal scan techniques were used to identify municipalities at risk. Multiple logistic regression was used to identify factors associated with tuberculosis in international migrants. Results: A total of 4037 cases of tuberculosis were reported in Brazil in international migrants. Municipalities at risk for this event were identified using the spatiotemporal scan technique, and a cluster was identified with ITT: +52.01% and ETT: +25.60%. A higher probability of TB infection was identified in municipalities with a TB incidence rate >14.40 cases/100 inhabitants, population >11,042 inhabitants, Gini index >0.49, and illiteracy rate >13.12%. A lower probability was found in municipalities with average per capita household income >BRL 456.43. Conclusions: It is recommended that health authorities implement monitoring and rigorous follow-up in affected areas to ensure proper diagnosis and treatment completion for international migrants, preventing disease spread to other communities. Full article

Reductions in tuberculosis (TB) incidence require identification of individuals at high risk of developing active disease, such as those with recent Mycobacterium tuberculosis (Mtb) infection. Using a prospective household contact (HHC) study in Kampala, Uganda, we diagnosed new Mtb infection using both the tuberculin skin test (TST) and interferon-gamma release assay (IGRA). Our study aimed to determine if the TST adds additional value to the characterization of IGRA converters. We identified 13 HHCs who only converted the IGRA (QFT-only converters), 39 HHCs who only converted their TST (TST-only converters), and 24 HHCs who converted both tests (QFT/TST converters). Univariate analysis revealed that TST-only converters were older. Additionally, increased odds of TST-only conversion were associated with older age (p = 0.02) and crowdedness (p = 0.025). QFT/TST converters had higher QFT quantitative values at conversion than QFT-only converters and a bigger change in TST quantitative values at conversion than TST-only converters. Collectively, these data indicate that TST conversion alone likely overestimates Mtb infection. Its correlation to older age suggests an “environmental” boosting response due to prolonged exposure to environmental mycobacteria. This result also suggests that QFT/TST conversion may be associated with a more robust immune response, which should be considered when planning vaccine studies. Full article

The World Health Organization (WHO)’s list of neglected tropical diseases (NTDs) highlights conditions that are responsible for devastating health, social and economic consequences, and yet, they are overlooked and poorly resourced. The NTD list does not include conditions caused by Gram-negative bacilli (GNB). Infections due to GNB cause significant morbidity and mortality and are prevalent worldwide. Southeast Asia is a WHO region of low- and middle-income countries carrying the largest burden of NTDs. Two significant health threats in Southeast Asia are Burkholderia pseudomallei (causing melioidosis) and hypervirulent Klebsiella pneumoniae (HvKp). Both diseases have high mortality and increasing prevalence, yet both suffer from a lack of awareness, significant under-resourcing, incomplete epidemiological data, limited diagnostics, and a lack of evidence-based treatment. Emerging evidence shows that both melioidosis and HvKp are spreading globally, including in high-income countries, highlighting the potential future global threat they pose. In this article, we review both conditions, identifying current trends and challenges in Southeast Asia and areas for future research. We also argue that melioidosis and HvKp merit inclusion as NTDs, and that mandatory global surveillance and reporting systems should be established, and we make an urgent call for research to better understand, detect, and treat these neglected diseases. Full article

In Australia, school-based human papillomavirus (HPV) vaccination was introduced initially for girls in 2007, and then also for boys in 2013. While studies have shown declines in the incidence of anogenital warts, there is a paucity of recent data analysis assessing the impact of vaccination on more severe disease. The National Hospital Morbidity Database of the Australian Institute of Health and Welfare (AIHW) hospitalisation admission data that included ICD-10-AM code A63.0 (‘anogenital warts’) as the diagnoses, for the years 2003–2020, were analysed to estimate hospitalisation rates per 100,000 mid-year population. The annual average hospitalisation rates per 100,000 population for anogenital warts in both genders combined in the age groups 10–19 years, 20–29 years, and 30–39 years decreased, respectively, from 16.9, 49.6, and 23.6 in 2003–2007 (pre-vaccine period) to 2.6, 15.2, and 14.6 in 2008–2020 (post-vaccine period), equating to declines of 84.7%, 69.4%, and 38.2%, respectively. Following the introduction of the boy’s vaccination, hospitalisation rates decreased further in the respective age bands from 4.3, 22.8, and 18.4 in 2008–2013 (early post-vaccine period) to 1.1, 9.3, and 11.7 in 2014–2020 (late post-vaccine period), equating to respective declines of 73.4%, 59.3%, and 36.4%. This analysis confirms that there is a substantial incremental decline in anogenital warts hospitalisations among Australians aged 10–39 years. Full article

Background: Although the Coxiella burnetii infection has been investigated in dogs, its role in human transmission remains to be fully established, particularly in close and daily human–dog contact settings, such as in Police K-9 Units. Methods: Accordingly, this study aimed to assess anti-C. burnetii antibodies in clinically healthy police officers by an in-house indirect immunofluorescence assay (IFA), and working dogs by a commercial IFA Kit, from the State Special Operations Battalion, Paraná, Southern Brazil. Results: Overall, 1/18 (5.5%) police officers and 9/30 (30.0%; CI 95% 16.66–47.88) dogs tested seropositive to anti-C. burnetii IgG antibodies. Conclusions: To date, this is the highest prevalence of Q fever seropositivity among military dogs worldwide. Despite the low sampling rate, a statistically significant association was found between seropositivity and female dogs (p = 0.0492). Further studies with larger sample sizes should be conducted to establish the prevalence of Q Fever in other Brazilian K-9 Units. In summary, this study is the first to conduct a concomitant serosurvey of police officers and working dogs, and its findings should be considered a warning for cross-exposure and transmission of Coxiella burnetii among Police K-9 Units in Brazil and worldwide. Full article

Antimicrobial resistance (AMR) is a public health concern in Uganda. We sought to conduct an extended profiling of AMR burden at selected Ugandan tertiary hospitals. We analyzed routine surveillance data collected between October 2020 and March 2023 from 10 tertiary hospitals. The analysis was stratified according to the hospital unit, age, gender, specimen type, and time. Up to 2754 isolates were recovered, primarily from pus: 1443 (52.4%); urine: 1035 (37.6%); and blood: 245 (8.9%). Most pathogens were Staphylococcus aureus, 1020 (37%), Escherichia coli, 808 (29.3%), and Klebsiella spp., 200 (7.3%). Only 28% of Escherichia coli and 42% of the other Enterobacterales were susceptible to ceftriaxone, while only 44% of Staphylococcus aureus were susceptible to methicillin (56% were MRSA). Enterococcus spp. susceptibility to vancomycin was 72%. The 5–24-year-old had 8% lower ampicillin susceptibility than the >65-year-old, while the 25–44-year-old had 8% lower ciprofloxacin susceptibility than the >65-year-old. The 0–4-year-old had 8% higher ciprofloxacin susceptibility. Only erythromycin susceptibility varied by sex, being higher in males. Escherichia coli ciprofloxacin susceptibility in blood (57%) was higher than in urine (39%) or pus (28%), as was ceftriaxone susceptibility in blood (44%) versus urine (34%) or pus (14%). Klebsiella spp. susceptibility to ciprofloxacin and meropenem decreased by 55% and 47%, respectively, during the evaluation period. During the same period, Escherichia coli ciprofloxacin susceptibility decreased by 40%, while Staphylococcus aureus gentamicin susceptibility decreased by 37%. Resistance was high across the Access and Watch antibiotic categories, varying with time, age, sex, specimen type, and hospital unit. Effective antimicrobial stewardship targeted at the critical AMR drivers is urgently needed. Full article

This study was carried out to identify the spatial distribution and characterize the clinical–epidemiological profile of Visceral Leishmaniasis (VL) in Maranhão state, Brazil, from 2009 to 2020. This descriptive ecological study collected sociodemographic and clinical data of VL cases from the Brazilian Notifiable Diseases Information System database. A spatial autocorrelation analysis (Moran statistics) was performed. From 2009 to 2020, 5699 cases of VL were reported, with incidence of 6.5 cases/100,000 and prevalence of 7.1 cases/100,000. The temporal analysis showed a significant growth in incidence from 2009 to 2018, followed by a significant decrease between 2019 and 2020. The Moran map shows hotspots of high values in the central–west and central–east regions, and hotspots of low values in the northern region of Maranhão. The profile of patients affected by VL comprises males (OR = 1.8; IC95% = 1.72–1.92), aged under 14 years, brown, and with incomplete elementary schooling. The main symptoms reported were fever, fatigue, and edema. The main diagnostic method was laboratory. The mortality rate was 6.8%, and co-infection with HIV was reported by 8.5% of patients. The results of this study indicated the increase in incidence and lethality, as well as the expansion, of leishmaniasis in the state of Maranhão. Full article

Active-case finding (ACF) using chest X-ray is an essential method of finding and diagnosing Tuberculosis (TB) cases that may be missed in Indonesia’s routine TB case finding. This study compares active and passive TB case-finding strategies. A retrospective study of TB case notification was conducted. Data between 1 January and 31 December 2021, was used. The population in this study were TB cases notified from Kulon Progo District health facilities, including those found through routine activities or active-case findings. A total of 249 TB cases were diagnosed in Kulon Progo in 2021, and 102 (41%) were bacteriologically confirmed. The TB patients’ ages ranged from 0 to 85 years (median 52, IQR 31–61). The majority of cases were male (59%, 147/249) and mostly among people aged 15–59 (61.4%, 153/249). The proportion of clinical TB diagnoses among cases found from active-case findings was 74.7% (68/91) while the proportion among passive-case findings was 50% (79/158). Active-case finding contributed 91 (36.5%) TB cases to the total cases detected in Kulon Progo in 2021. The use of chest X-rays in active-case findings likely contributed to the detection of a higher proportion of clinical TB than in passive-case findings. Full article

In resourced settings, adults living with perinatally acquired HIV are approaching the 5th decade of life. Their clinical and psychological outcomes highlight potential future issues for the much larger number of adolescents growing up with HIV in sub–Saharan Africa, and will inform the development of appropriate healthcare services. Lifelong exposure to HIV, and increasingly to antiretroviral therapy throughout growth and development, contrasts with adults acquiring HIV in later life. This review describes the clinical outcomes for adults living with perinatally acquired HIV including post transition mortality, morbidity and retention in care. Rates of viral suppression, drug resistance and immunological function are explored. Co-morbidities focus on metabolic, cardiovascular, respiratory and bone health with quality-of-life data including neurocognitive functioning and mental health. Sexual and reproductive health including vaccine-preventable disease and the prevention of onward transmission to partners and infants are considered. The data gaps and future research questions to optimise outcomes for this emerging adult cohort are highlighted. Full article

Pegylated interferon alpha 2a continues to be used for the treatment of chronic hepatitis D. The reported on-treatment virologic response varies between 17 and 47%, with relapses in more than 50% of these patients. No stopping rules have been defined, and the duration of the treatment is not clearly established, but it should be between 48 and 96 weeks. In total, 76 patients with compensated liver disease treated with peg-interferon according to the Romanian National protocol for the treatment of hepatitis D were retrospectively included. The duration of treatment was up to 96 weeks, with the following stopping rules: less than a 2 log HDV RNA decrease by week 24 and less than a 1 log decrease every 6 months afterwards. Six months after stopping the treatment, it can be restarted for unlimited cycles. The inclusion criteria were aged above 18, HBs Ag-positive, HDV RNA detectable, ALT above ULN and/or liver fibrosis at least F1 at liver biopsy, or Fibrotest and/or Fibroscan higher than 7 KPa and/or inflammation at least A1 at liver biopsy or Fibrotest. We monitored our patients for a total period of 4 years (including those that repeated the cycle). After the first 6 months of treatment, 27 patients (35.5%) had a greater than 2 log HDV RNA decrease, 19 of them achieving undetectable HDV RNA. Seventeen patients (22.3%) had undetectable HDV RNA 24 weeks after stopping 96 weeks of treatment, and none relapsed in the following 2 years. Of these 17 patients, 6 were cirrhotic, and 4 had F3. Undetectable HDV RNA at 24 weeks was the only parameter that predicted a long-term suppression of HDV RNA. In 49 patients, the treatment was stopped after 6 months according to protocol, but it was restarted 6 months later. Five of these patients finished a 48-week course of treatment; none achieved undetectable HDV RNA. During the first course of therapy, 45 patients had at least one moderate adverse reaction to treatment. In one patient, the treatment was stopped due to a serious adverse event (osteomyelitis). Treatment doses had to be reduced in 29 patients. The virologic response at week 24 can select the patients who will benefit from continuing the treatment from those who should be changed to another type of medication when available. Full article

Objective: This study aimed to improve dengue fever predictions in Singapore using a machine learning model that incorporates meteorological data, addressing the current methodological limitations by examining the intricate relationships between weather changes and dengue transmission. Method: Using weekly dengue case and meteorological data from 2012 to 2022, the data was preprocessed and analyzed using various machine learning algorithms, including General Linear Model (GLM), Support Vector Machine (SVM), Gradient Boosting Machine (GBM), Decision Tree (DT), Random Forest (RF), and eXtreme Gradient Boosting (XGBoost) algorithms. Performance metrics such as Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and R-squared ($R^2$) were employed. Results: From 2012 to 2022, there was a total of 164,333 cases of dengue fever. Singapore witnessed a fluctuating number of dengue cases, peaking notably in 2020 and revealing a strong seasonality between March and July. An analysis of meteorological data points highlighted connections between certain climate variables and dengue fever outbreaks. The correlation analyses suggested significant associations between dengue cases and specific weather factors such as solar radiation, solar energy, and UV index. For disease predictions, the XGBoost model showed the best performance with an MAE = 89.12, RMSE = 156.07, and $R^2$ = 0.83, identifying time as the primary factor, while 19 key predictors showed non-linear associations with dengue transmission. This underscores the significant role of environmental conditions, including cloud cover and rainfall, in dengue propagation. Conclusion: In the last decade, meteorological factors have significantly influenced dengue transmission in Singapore. This research, using the XGBoost model, highlights the key predictors like time and cloud cover in understanding dengue’s complex dynamics. By employing advanced algorithms, our study offers insights into dengue predictive models and the importance of careful model selection. These results can inform public health strategies, aiming to improve dengue control in Singapore and comparable regions. Full article

Melioidosis is a potentially life-threatening infection. This study aimed to assess the melioidosis knowledge among distinct participant groups in the tropical Top End of the Northern Territory (NT) of Australia. Participants were categorised into three groups: NT medical students and health research staff (Group 1: Hi-Ed), Aboriginal Rangers and Aboriginal Healthcare Workers (Group 2: Rangers/AHWs), and patients with a history of melioidosis infection (Group 3: Patients). A questionnaire was developed to collect data on demographics, risk and protective factor awareness, and knowledge acquisition sources. We used responses to calculate indices for risk knowledge (RKI), protective knowledge (PKI), overall melioidosis knowledge (MKI), and information sources (ISI). We found that 93.6% of participants in Group 1 (Hi-Ed) said that they had heard of melioidosis, followed by 81.5% in Group 3 (Patients), and 72.0% in Group 2 (Rangers/AHWs). Group 1 (Hi-Ed) participants demonstrated greater knowledge of risk-increasing behaviours but had gaps in knowledge of clinical risks like diabetes. Multiple regression revealed that the number of resources used was the only significant predictor of MKI. There are varying melioidosis knowledge levels across different NT participant groups. Targeted educational interventions are needed to enhance melioidosis awareness. A weblink with an interactive summary of our analysis can be found under Results part. Full article

Background: The birthrate of Black preterm (BPT) infants is 65% higher than White preterm (WPT) infants with a BPT mortality that is 2.3 times higher. The incidence of culture-positive late-onset sepsis is as high as 41% in very-preterm infants. The main purpose of this study was to examine thermal gradients and the heart rate in relation to the onset of infection. This report presents disparities in very-preterm infection incidence, bacteria, and mortality data amongst BPT and WPT infants. Methods: 367 preterms born at <32 weeks gestational age (GA) between 2019–2023 in five neonatal intensive care units (NICUs) were enrolled to study the onset of infections and dispositions; REDCap data were analyzed for descriptive statistics. Results: The 362 infants for analyses included 227 BPTs (63.7%) and 107 WPTs (29.6%), with 28 infants of other races/ethnicities (Hispanic, Asian, and other), 50.6% female, mean GA of 27.66 weeks, and 985.24 g birthweight. BPT infants averaged 968.56 g at birth (SD 257.50), and 27.68 (SD 2.07) weeks GA, compared to WPT infants with a mean birthweight of 1006.25 g (SD 257.77, p = 0.2313) and 27.67 (SD 2.00, p = 0.982) weeks GA. Of the 426 episodes of suspected infections evaluated across all the enrolled infants, the incidence of early-onset sepsis (EOS) was 1.9%, with BPT infants having 2.50 times higher odds of EOS than WPT infants (p = 0.4130, OR (odds ratio) = 2.50, p_or = 0.408). The overall incidence of late-onset sepsis (LOS) was 10.8%, with LOS in 11.9% of BPT infants versus 9.3% (p = 0.489, OR = 1.21, p_or = 0.637) of WPT infants. BPT infants made up 69.2% of the 39 infants with Gram-positive infections vs. 25.6% for WPT infants; 16 infants had Gram-negative culture-positive infections, with 81.2% being BPT infants versus 18.8% being WPT infants. Of the 27 urinary tract infections, 78% were in BPTs. The necrotizing enterocolitis incidence was 6.9%; the incidence in BPT infants was 7.5% vs. 6.5% in WPT infants. The overall mortality was 8.3%, with BPTs at 8.4% vs. WPT infants at 9.3%, (p = 0.6715). Conclusions: BPTs had a higher rate of positive cultures, double the Gram-negative infections, a much higher rate of urinary tract infections, and a higher rate of mortality than their WPT counterparts. This study emphasizes the higher risk of morbidity and mortality for BPTs. Full article

Background: The red imported fire ant (RIFA) is one of the world’s most destructive invasive species. RIFA stings are painful and can lead to allergic reactions, including life-threatening anaphylaxis, yet health impacts remain inadequately defined. Methods: We searched MEDLINE (Ovid) and Google Scholar (grey literature) from inception until 20 September 2023 for articles in English using search terms related to red imported fire ants and allergies, including anaphylaxis. Results: Approximately a third of the population in RIFA-infested areas are stung each year. The most frequent reaction is a sterile 1–2 mm pseudo pustule on the skin. Approximately 20% of stings cause a large local reaction and between about 0.5% and 2% stings cause a systemic allergic reaction which can range from skin symptoms to life-threatening anaphylaxis. Local biodiversity is also significantly disrupted by invading RIFA and may lead to complex adverse effects on human health, from agriculture losses to expanded ranges for pathogen vectors. Conclusions: The potential for red imported fire ants to establish themselves as an invasive species in the Western Pacific presents a substantial and costly health issue. Successful eradication and surveillance programs, to identify and eradicate new incursions, would avoid substantial health impacts and costs. Full article

Snakebite envenoming (SBE) is a neglected tropical disease (NTD). Community-based studies from sub-Saharan Africa are urgently required as data on the incidence are scarce. This study aimed to determine the lifetime prevalence of snakebites in rural Gabon by preparing the conduct of a larger regional survey. A cross-sectional community-based epidemiological survey in Sindara, Ngounie province, was conducted. Households were interviewed about the history of snakebites of household members to calculate lifetime prevalence. In addition, the average annual incidence rate per 100,000 over the last 5 years was calculated. A total of 771 inhabitants were enrolled, of which 5 (0.65%; 95% confidence interval (95% CI: 0.2–1.5%)) were victims of snakebites. Over the past 5 years, annual incidence was 77 bites per 100,000 (95% CI: 0–620). This study provides a first rough estimate of the incidence of SBE from rural central Gabon, demonstrating the importance of this NTD. Key Contribution: The estimated annual incidence of snakebites found was 77 per 100,000. Snakebites occurred mainly during agricultural activities. Full article

Vaccination is one of the main advancements in public health in the prophylaxis of infectious diseases. We intend to describe the general knowledge about vaccines/vaccination among Brazilian immigrants in Portugal, characterize their attitudes toward vaccination, and describe their knowledge of the yellow fever (YF) vaccine. A cross-sectional study was conducted using a self-completion questionnaire (face-to-face or remote). A total of 542 people participated in the study; the mean age was 36.81 years; 40.1% were male; 44.8% had their 12th year of schooling; and 27.0% had resided for ≥10 years in Portugal. Regarding general knowledge about vaccination, 53.8% answered at least 6/8 questions correctly. A total of 37.1% tended to have a favorable attitude toward vaccination. Concerning traveling, 76.7% attributed the risk of disease at the destination as the main reason for accepting vaccines. A total of 89.3% knew that there was a risk of YF in Brazil. A total of 40% answered correctly only one question about the YF vaccine; 21.6% did not answer any questions correctly. Thus, most of the Brazilian immigrants in this study have high general knowledge about vaccines/vaccination, few have a favorable attitude, and their knowledge about the YF vaccine is scarce. This could limit vaccination adherence when visiting Brazil, making health education actions necessary to increase knowledge and prevent YF risks. Full article