Public Health Laboratory Ivo de Carneri

Schistosomiasis is a parasitic disease that mostly affects school-age children in sub-Saharan Africa. Preventive chemotherapy is the mainstay of control. Other interventions, including behavior change communication (BCC), are recommended to reduce transmission and ultimately achieve elimination. We determined the effect of BCC interventions on schistosomiasis-related knowledge, attitudes, and practices (KAP) among children who were exposed to different BCC intervention frequencies and durations within the 4-year SchistoBreak project in Pemba, Tanzania. Annual surveys were carried out from 2020 to 2024 in 18 primary schools. Schistosomiasis-related KAP were assessed in randomly selected children attending grades 3-5. BCC interventions were implemented for one period (4 schools), two periods without gap (3 schools), two periods with a 1-year gap (1 school), or never (10 schools). Linear and logistic mixed-models with random effect were applied to assess associations between BCC exposure categories as predictors and knowledge or attitude scores, or unsafe washing practices as the outcome variable in 2024. A total of 4196 children participated in the surveys. Knowledge and attitude improved with continuous or repeated exposure to BCC interventions. In 2024, the knowledge scores were significantly higher in children who received BCC intervention once (difference: 1.2, 95% confidence interval (CI): 0.6-1.9) or twice (difference: 2.1, 95% CI: 1.4-2.7), as compared to children who never received BCC interventions. Children who were exposed to BCC interventions twice (difference: 1.2, 95% CI: 0.8-1.6) had significantly higher attitude scores in 2024. Washing practices improved regardless of whether or not children were exposed to BCC. The washing platforms installed in intervention areas were known by up to half of the children exposed to BCC interventions, but their use was considerably lower, varying between 7.5% and 43.1%. We demonstrated that BCC interventions were able to improve schistosomiasis-related knowledge and attitudes in schoolchildren. Repeated BCC interventions might be required for sustainable long-term impact. ISRCTN, ISRCTN91431493. Registered 11 February. 2020, https://www.isrctn.com/ISRCTN91431493.

Intestinal protozoa infections present a major public health challenge, particularly in areas with poor sanitation and limited access to clean water. Effective diagnostic methods are critical, yet traditional microscopy, though widely used for its simplicity, lacks the sensitivity and specificity of modern techniques like real-time Polymerase Chain Reaction (qPCR), making the latter a more effective tool for monitoring and assessing the burden of intestinal protozoa diseases. In this study, we implemented two duplex qPCR assays to detect Entamoeba dispar + Entamoeba histolytica and Cryptosporidium spp. + Chilomastix mesnili, along with singleplex assays for Giardia duodenalis and Blastocystis spp., using a 10 µL reaction volume. This marks the first molecular detection of Chilomastix mesnili by qPCR, enhancing diagnostic precision. Using these, we analyzed stool samples from 70 patients on Pemba Island, Tanzania, before and 54 samples after treatment with 20, 25, or 30 mg of emodepside or placebo, aiming to assess protozoa prevalence for this region and emodepside’s potential antiprotozoal effects. Our qPCR reliably detected protozoa in 74.4% of samples, with Entamoeba histolytica and Entamoeba dispar in 31.4% of cases. Notably, one-third of these infections were caused by Entamoeba histolytica. No significant reduction in protozoa was observed after emodepside treatment compared to placebo. The study highlights the utility of qPCR in providing species-level differentiation and improving the speed and cost-effectiveness of testing. The high prevalence of protozoa in this region underscores the need for continued monitoring and control efforts, though emodepside was not effective against protozoa infections.

The World Health Organization recommends the use of the microscopy-based Kato-Katz thick smear for diagnosing soil-transmitted helminth (STH) infections. Despite its simplicity and cost-effectiveness, the Kato-Katz method faces challenges, including reader subjectivity and reduced sensitivity. Real-time polymerase chain reaction (qPCR) technology offers standardized readouts and higher sensitivity, making it suitable for STH diagnosis and monitoring the treatment efficacy of emodepside within the framework of randomized controlled trials. We evaluated the performance of Kato-Katz versus qPCR for assessing treatment efficacy in terms of cure rates, of single doses of 5, 10, 15, 20, 25 and 30 mg of emodepside compared to 400 mg albendazole. Spearman's rank correlation coefficient examined the correlation between STH eggs per gram in stool samples and qPCR Ct values. Diagnostic sensitivity of qPCR was calculated using a Bayesian latent class modelling approach with data from Ascaris lumbricoides infections. Agreement between Kato-Katz and qPCR at baseline was 93.57% for Trichuris trichiura, and 73.49% for both hookworm and A. lumbricoides. For the latter helminth qPCR demonstrated higher sensitivity (85.00% vs. 47.70%) and slightly lower specificity (93.40% vs. 99.40%) compared to Kato-Katz. We observed a fair to moderate agreement with negative correlation between Ct values and Kato-Katz egg counts. Treatment efficacy, as assessed by qPCR, was lower for all doses of emodepside and albendazole compared to Kato-Katz. Nonetheless, emodepside demonstrated higher cure rates against T. trichiura and A. lumbricoides infections compared to albendazole. Our study confirmed that qPCR is a sensitive diagnostic method for diagnosing STH infections compared to Kato-Katz and serves as a valuable tool for determining treatment efficacy in clinical trials. Furthermore, qPCR confirmed the better treatment efficacy of emodepside compared to albendazole, despite indicating lower cure rates than Kato-Katz.

BackgroundHyperglycemia during pregnancy leads to adverse maternal and fetal outcomes. Thus, strict monitoring of blood glucose levels is warranted. This study aims to determine the association of early to mid-pregnancy HbA1c levels with the development of pregnancy complications in women from three countries in South Asia and Sub-Saharan Africa.MethodsWe performed a secondary analysis of the AMANHI (Alliance for Maternal and Newborn Health Improvement) cohort, which enrolled 10,001 pregnant women between May 2014 and June 2018 across Sylhet-Bangladesh, Karachi-Pakistan, and Pemba Island-Tanzania. HbA1c assays were performed at enrollment (8 to < 20 gestational weeks), and epidemiological data were collected during 2–3 monthly household visits. The women were followed-up till the postpartum period to determine the pregnancy outcomes. Multivariable logistic regression models assessed the association between elevated HbA1c levels and adverse events while controlling for potential confounders.ResultsA total of 9,510 pregnant women were included in the analysis. The mean HbA1c level at enrollment was found to be the highest in Bangladesh (5.31 ± 0.37), followed by Tanzania (5.22 ± 0.49) and then Pakistan (5.07 ± 0.58). We report 339 stillbirths and 9,039 live births. Among the live births were 892 preterm births, 892 deliveries via cesarean section, and 532 LGA babies. In the multivariate pooled analysis, maternal HbA1c levels of ≥ 6.5 were associated with increased risks of stillbirths (aRR = 6.3, 95% CI = 3.4,11.6); preterm births (aRR = 3.5, 95% CI = 1.8–6.7); and Large for Gestational Age (aRR = 5.5, 95% CI = 2.9–10.6).ConclusionMaternal HbA1c level is an independent risk factor for predicting adverse pregnancy outcomes such as stillbirth, preterm birth, and LGA among women in South Asia and Sub-Saharan Africa. These groups may benefit from early interventional strategies.

BackgroundCopper (Cu), an essential trace mineral regulating multiple actions of inflammation and oxidative stress, has been implicated in risk for preterm birth (PTB). ObjectivesThis study aimed to determine the association of maternal Cu concentration during pregnancy with PTB risk and gestational duration in a large multicohort study including diverse populations. MethodsMaternal plasma or serum samples of 10,449 singleton live births were obtained from 18 geographically diverse study cohorts. Maternal Cu concentrations were determined using inductively coupled plasma mass spectrometry. The associations of maternal Cu with PTB and gestational duration were analyzed using logistic and linear regressions for each cohort. The estimates were then combined using meta-analysis. Associations between maternal Cu and acute-phase reactants (APRs) and infection status were analyzed in 1239 samples from the Malawi cohort. ResultsThe maternal prenatal Cu concentration in our study samples followed normal distribution with mean of 1.92 μg/mL and standard deviation of 0.43 μg/mL, and Cu concentrations increased with gestational age up to 20 wk. The random-effect meta-analysis across 18 cohorts revealed that 1 μg/mL increase in maternal Cu concentration was associated with higher risk of PTB with odds ratio of 1.30 (95% confidence interval [CI]: 1.08, 1.57) and shorter gestational duration of 1.64 d (95% CI: 0.56, 2.73). In the Malawi cohort, higher maternal Cu concentration, concentrations of multiple APRs, and infections (malaria and HIV) were correlated and associated with greater risk of PTB and shorter gestational duration. ConclusionsOur study supports robust negative association between maternal Cu and gestational duration and positive association with risk for PTB. Cu concentration was strongly correlated with APRs and infection status suggesting its potential role in inflammation, a pathway implicated in the mechanisms of PTB. Therefore, maternal Cu could be used as potential marker of integrated inflammatory pathways during pregnancy and risk for PTB.

Benign paroxysmal positional vertigo (BPPV) is a prevalent and disabling pathology. Its diagnosis and treatment according to clinical practice guidelines is carried out through canalicular repositioning maneuvers, but these maneuvers are not performed routinely in primary care consultations. To analyse the baseline data from the VERTAP randomised community trial that evaluates whether a blended course is effective in improving the adherence of primary care physicians to clinical practice guidelines. Baseline data 2021. 20 primary healthcare centers with an assigned population of 514157. sex, age, diagnoses related to vertigo/dizziness, anti-vertigo medications prescribed, number of referrals to the otolaryngologist and neurologist, complementary examinations, and sick leave. Vertigo/dizziness-related diagnoses totaled 21 359 cases, with a prevalence of 4.15%. Women made up 51.49% of cases. Median age was 52.00 (41.00, 65.00) years. Non-specific diagnoses totaled 18 617 (87.16%), including dizziness (n = 13 846, 64.83%), unspecified vestibular function disorder (n = 962, 4.50%), aural vertigo (n = 7, 0.03%), and other (n = 3802, 17.80%). Specific diagnoses totalled 2742 (12.84%), including BPPV (n = 1665, 7.80%), vestibular neuritis (n = 24, 0.11%), Menière's disease (n = 992, 4.64%), and central vertigo (n = 61, 0.29%). Anti-vertigo drugs prescribed included betahistine (n = 13 338, 62.45%), sulpiride (n = 3379, 15.82%), and dimenhydrinate (n = 20, 0.093%). Complementary examinations included computed tomography (n = 5704, 26.70%) and magnetic resonance (n = 604, 2.83%). One temporary disability for work (n = 1468, 6.87%); ≥2 temporary disability for work (n = 275, 1.29%). The majority of diagnostic records related to vertigo/dizziness were non-specific (9 out of 10). The number of prescriptions for betahistine, and referrals, mainly to an otolaryngologist, are considerable and an avoidable expense. Better knowledge about vertigo/dizziness in care could improve the diagnostic and therapeutic accuracy of this pathology as well as the social and health costs it produces.

ABSTRACT Background High-quality essential newborn care (ENC) can improve newborn health and reduce preventable newborn mortality. The World Health Organization recommends specific ENC interventions. Video recordings have potential as a tool for assessment of clinical care also in low and middle-income countries. Objective To use video observations of healthy newborns to describe ENC practices in a low-income setting and compare actual clinical practice with WHO recommendations. Method This is a cross-sectional observational study. Video records of neonatal interventions to 324 healthy newborns were assessed. They were obtained at baseline of a pre-post intervention study during a 10-week study period in Pemba, Tanzania. Data also included postnatal structured questionnaires. Eight ENC interventions and quality indicators were defined as per the WHO recommendations. Descriptive statistics were used to summarize ENC practices and maternal and neonatal characteristics. Results None of the newborns received all eight recommended ENC interventions. The median duration of separation from the mother was 25 minutes and 15 seconds (ranging from 22 seconds to 3 hours and 36 minutes), 51% of the newborns received proper thermal care during the separation. Twenty-one percent had sufficient umbilical cord care, 8% were stimulated for breathing, 69% were observed at least once by healthcare staff and 9% did undergo suctioning. None of the newborns received antibiotic ointments or vitamin K. Conclusion Video recording of healthy newborns was feasible. The study identified omission of key ENC practices including proper thermal care, skin-to-skin contact and establishment of breastfeeding within the first hour of life, vitamin K administration as well as application of unnecessary practices such as excessive suctioning of breathing newborns.

BackgroundThe treatment coverage of control programs providing benzimidazole (BZ) drugs to eliminate the morbidity caused by soil-transmitted helminths (STHs) is unprecedently high. This high drug pressure may result in the development of BZ resistance in STHs and so there is an urgent need for surveillance systems detecting molecular markers associated with BZ resistance. A critical prerequisite to develop such systems is an understanding of the gene family encoding β-tubulin proteins, the principal targets of BZ drugs.Methodology and principal findingsFirst, the β-tubulin gene families of Ascaris lumbricoides and Ascaris suum were characterized through the analysis of published genomes. Second, RNA-seq and RT-PCR analyses on cDNA were applied to determine the transcription profiles of the different gene family members. The results revealed that Ascaris species have at least seven different β-tubulin genes of which two are highly expressed during the entire lifecycle. Third, deep amplicon sequencing was performed on these two genes in more than 200 adult A. lumbricoides (Ethiopia and Tanzania) and A. suum (Belgium) worms, to investigate the intra- and inter-species genetic diversity and the presence of single nucleotide polymorphisms (SNPs) that are associated with BZ resistance in other helminth species; F167Y (TTC>TAC or TTT>TAT), E198A (GAA>GCA or GAG>GCG), E198L (GAA>TTA) and F200Y (TTC>TAC or TTT>TAT). These particular SNPs were absent in the two investigated genes in all three Ascaris populations.SignificanceThis study demonstrated the presence of at least seven β-tubulin genes in Ascaris worms. A new nomenclature was proposed and prioritization of genes for future BZ resistance research was discussed. This is the first comprehensive description of the β-tubulin gene family in Ascaris and provides a framework to investigate the prevalence and potential role of β-tubulin sequence polymorphisms in BZ resistance in a more systematic manner than previously possible.

BackgroundBabies born early and/or small for gestational age in Low and Middle-income countries (LMICs) contribute substantially to global neonatal and infant mortality. Tracking this metric is critical at a population level for informed policy, advocacy, resources allocation and program evaluation and at an individual level for targeted care. Early prenatal ultrasound examination is not available in these settings, gestational age (GA) is estimated using new-born assessment, last menstrual period (LMP) recalls and birth weight, which are unreliable. Algorithms in developed settings, using metabolic screen data, provided GA estimates within 1–2 weeks of ultrasonography-based GA. We sought to leverage machine learning algorithms to improve accuracy and applicability of this approach to LMICs settings.MethodsThis study uses data from AMANHI-ACT, a prospective pregnancy cohorts in Asia and Africa where early pregnancy ultrasonography estimated GA and birth weight are available and metabolite screening data in a subset of 1318 new-borns were also available. We utilized this opportunity to develop machine learning (ML) algorithms. Random Forest Regressor was used where data was randomly split into model-building and model-testing dataset. Mean absolute error (MAE) and root mean square error (RMSE) were used to evaluate performance. Bootstrap procedures were used to estimate confidence intervals (CI) for RMSE and MAE. For pre-term birth identification ROC analysis with bootstrap and exact estimation of CI for area under curve (AUC) were performed.ResultsOverall model estimated GA had MAE of 5.2 days (95% CI 4.6–6.8), which was similar to performance in SGA, MAE 5.3 days (95% CI 4.6–6.2). GA was correctly estimated to within 1 week for 85.21% (95% CI 72.31–94.65). For preterm birth classification, AUC in ROC analysis was 98.1% (95% CI 96.0–99.0; p < 0.001). This model performed better than Iowa regression, AUC Difference 14.4% (95% CI 5–23.7; p = 0.002).ConclusionsMachine learning algorithms and models applied to metabolomic gestational age dating offer a ladder of opportunity for providing accurate population-level gestational age estimates in LMICs settings. These findings also point to an opportunity for investigation of region-specific models, more focused feasible analyte models, and broad untargeted metabolome investigation.