We conducted a cross sectional study to assess 1) the association between access to basic sanitation and fecal contamination of sentinel toy balls and 2) if other sanitation factors such as shared use and cleanliness are associated with fecal contamination of sentinel toy balls. We assessed sanitation facilities in 454 households with a child aged 6–24 months in rural Bangladesh. We defined “basic” sanitation as access to improved sanitation facilities (pit latrine with a slab or better) not shared with other households. In each household, an identical toy ball was given to the target child. After 24 hours, the balls were rinsed to enumerate fecal coliforms as an indicator of household fecal contamination. Households with basic sanitation had lower fecal coliform contamination than households with no access to basic sanitation (adjusted difference in means: −0.31 log₁₀ colony forming units [CFU]/toy ball; 95% confidence interval [CI]: −0.61, −0.01). Shared sanitation facilities of otherwise improved type were more likely to have visible feces on the latrine slab compared with private facilities. Among households with access to improved sanitation, households with no visible feces on the latrine slab had less toy ball contamination than households with visible feces on the latrine slab (adjusted difference in means: −0.38 log₁₀ CFU/toy ball; 95% CI: −0.77, 0.02). Access to basic sanitation may prevent fecal contamination of the household environment. An Improved sanitation facility used by an individual household may be better in preventing household fecal contamination compared with improved facilities shared with other households.

Purpose As of 2024, 123.2 million people had been forcibly displaced as a result of persecution, armed conflict or climate-related catastrophes, and these numbers are predicted to rise. There is a growing awareness of possible intergenerational effects of trauma on life-course health and well-being, however few studies have followed individuals longitudinally starting prenatally. This paper describes the first large prenatal birth cohort study in a refugee context in a lower middle-income country. This study aims to investigate the potential lifespan health and developmental implications of being born into a protracted humanitarian context, and what factors can buffer from the adversity posed by conflict and displacement. Participants We outline our approach of recruiting, consenting and gathering data from pregnant Rohingya refugee and host community women (N=2888; 80% Rohingya) over the course of 12 months in Cox’s Bazar, Bangladesh. Findings to date A fifth wave of data collection, when children were 6 months old, was completed in April 2025. Rohingya women were substantially less literate; were marrying and having children at slightly younger ages, were more likely to live in crowded, resource-limited households and exhibited higher rates of clinically significant post-traumatic stress disorder and anxiety than host community women. Future plans There is a critical need for research in displaced populations in order to elucidate potentially lasting transgenerational impacts of experiencing conflict and displacement trauma, and the prenatal and postnatal factors that support health and development across the life span. The next follow-up is planned when the children turn 36 months of age (starting March 2026).

Dengue (DENV), Chikungunya (CHIKV), and Zika (ZIKV) are emerging arboviral threats in Bangladesh, transmitted by Aedes mosquitoes thriving in urban Dhaka. Overlapping symptoms complicate diagnosis, and Bangladesh-specific data on arboviral antibody reactivity are limited. In four hospitals of Dhaka, we conducted a cross-sectional study on 438 febrile patients aged ≥10 years, collecting samples between September and December 2023 to describe arboviral antibody reactivity and their distribution across selected demographic and environmental characteristics. Rapid diagnostic tests (RDTs) for DENV and CHIKV were performed, followed by enzyme-linked immunosorbent assay (ELISA) on RDT-reactive samples. Participants had a mean age of 30 years (±13.5); two-thirds were male, and most lived in crowded, low-income households. RDTs indicated DENV/CHIKV antibody reactivity in 40% of participants; 170 samples underwent ELISA, suggesting DENV IgG reactivity in 33.5% and IgM reactivity in 15.5%. CHIKV IgG reactivity (0.7%) was low and ZIKV IgG was reactive in 21% of total samples, and IgM was reactive in one (0.2%); most ZIKV IgG-reactive samples also showed DENV IgG reactivity, suggesting cross-reactivity. DENV IgG and IgM reactivity were associated with lower education, while ZIKV IgM reactivity was associated with older age. Awareness of Aedes mosquitoes was low, and environmental risk factors were common. This study provides cross-sectional data on serological reactivity against DENV, CHIKV, and ZIKV among febrile patients attending four hospitals of Dhaka, without aiming to establish etiologic causes of illness. ZIKV IgG antibody reactivity requires confirmatory testing to distinguish true infections from other arboviral cross-reactivity. Strengthened community-based surveys, better public awareness, and sustained vector control are critical for reducing arboviral disease risks in urbanizing settings like Dhaka, Bangladesh.

Gestational weight gain (GWG) is a critical determinant of maternal and neonatal health, yet its patterns and consequences in displaced populations remain understudied. This study examined the association between GWG and birth outcomes among Forcibly Displaced Rohingya (FDR) women in Cox’s Bazar, Bangladesh. We conducted a longitudinal cohort study from October 2022 to October 2024, enrolling 2888 pregnant women at different stages of pregnancy. Among them, 301 were recruited in the first trimester and followed through the third trimester, with 231 neonatal outcomes recorded within 72 hours of delivery. Overall, 66.8% of women experienced inadequate GWG. Despite the high prevalence of inadequate GWG, mean birth weight (2.79 kg) and mean gestational age at delivery (38.6 weeks) were within favorable ranges. Inadequate GWG was more common in mothers aged 30–39 years (p = 0.061) but significantly less common in underweight mothers (p = 0.012). GWG was positively associated with neonatal birth weight, length, and weight–length ratio (WLR) Z score, but not with gestational age. After adjusting for confounding factors, inadequate GWG showed a significant independent association with lower birth length (p = 0.016). These findings highlight the need for targeted interventions in displaced populations.