Continuity of Trust: Health Systems' Role in Advancing Health Equity Beyond the COVID-19 Pandemic

Given COVID-19's disproportionate impact on populations that identify as Black, Indigenous, and People of Color (BIPOC) in the United States, researchers and advocates have recommended that health systems and institutions deepen their engagement with community-based organizations (CBOs) with longstanding relationships with these communities. However, even as CBOs leverage their earned trust to promote COVID-19 vaccination, health systems and institutions must also address underlying causes of health inequities more broadly. In this commentary, we discuss key lessons learned about trust from our participation in the U.S. Equity-First Vaccination Initiative, an effort funded by The Rockefeller Foundation to promote COVID-19 vaccination equity. The first lesson is that trust cannot be "surged" to meet the needs of the moment until it is no longer deemed important; rather, it must predate and outlast the crisis. Second, to generate long-term change, health systems cannot simply rely on CBOs to bridge the trust gap; instead, they must directly address the root causes of this gap among BIPOC populations.

Separating signal from noise in wastewater data: An algorithm to identify community-level COVID-19 surges in real time

Wastewater monitoring has provided health officials with early warnings for new COVID-19 outbreaks, but to date, no approach has been validated to distinguish signal (sustained surges) from noise (background variability) in wastewater data to alert officials to the need for heightened public health response. We analyzed 62 wk of data from 19 sites participating in the North Carolina Wastewater Monitoring Network to characterize wastewater metrics around the Delta and Omicron surges. We found that wastewater data identified outbreaks 4 to 5 d before case data (reported on the earlier of the symptom start date or test collection date), on average. At most sites, correlations between wastewater and case data were similar regardless of how wastewater concentrations were normalized and whether calculated with county-level or sewershed-level cases, suggesting that officials may not need to geospatially align case data with sewershed boundaries to gain insights into disease transmission. Although wastewater trend lines captured clear differences in the Delta versus Omicron surge trajectories, no single wastewater metric (detectability, percent change, or flow-population normalized viral concentrations) reliably signaled when these surges started. After iteratively examining different combinations of these three metrics, we developed the Covid-SURGE (Signaling Unprecedented Rises in Groupwide Exposure) algorithm, which identifies unprecedented signals in the wastewater data. With a true positive rate of 82%, a false positive rate of 7%, and strong performance during both surges and in small and large sites, our algorithm provides public health officials with an automated way to flag community-level COVID-19 surges in real time.

Post-Recovery Relapse of Children Treated with a Simplified, Combined Nutrition Treatment Protocol in Mali: A Prospective Cohort Study

The present study aimed to determine the 6-month incidence of relapse and associated factors among children who recovered from acute malnutrition (AM) following mid-upper arm circumference (MUAC)-based simplified combined treatment using the ComPAS protocol. A prospective cohort of 420 children who had reached a MUAC ≥ 125 mm for two consecutive measures was monitored between December 2020 and October 2021. Children were seen at home fortnightly for 6 months. The overall 6-month cumulative incidence of relapse [95%CI] into MUAC < 125 mm and/or edema was 26.1% [21.7; 30.8] and 1.7% [0.6; 3.6] to MUAC < 115 mm and/or edema. Relapse was similar among children initially admitted to treatment with a MUAC < 115 mm and/or oedema and among those with a MUAC ≥ 115 mm but <125 mm. Relapse was predicted by lower anthropometry both at admission to and discharge from treatment, and a higher number of illness episodes per month of follow-up. Having a vaccination card, using an improved water source, having agriculture as the main source of income, and increases in caregiver workload during follow-up all protected from relapse. Children discharged as recovered from AM remain at risk of relapsing into AM. To achieve reduction in relapse, recovery criteria may need to be revised and post-discharge strategies tested.

Mapping environmental suitability of Haemagogus and Sabethes spp. mosquitoes to understand sylvatic transmission risk of yellow fever virus in Brazil

BACKGROUND

Yellow fever (YF) is an arboviral disease which is endemic to Brazil due to a sylvatic transmission cycle maintained by infected mosquito vectors, non-human primate (NHP) hosts, and humans. Despite the existence of an effective vaccine, recent sporadic YF epidemics have underscored concerns about sylvatic vector surveillance, as very little is known about their spatial distribution. Here, we model and map the environmental suitability of YF's main vectors in Brazil, Haemagogus spp. and Sabethes spp., and use human population and NHP data to identify locations prone to transmission and spillover risk.

METHODOLOGY/PRINCIPAL FINDINGS

We compiled a comprehensive set of occurrence records on Hg. janthinomys, Hg. leucocelaenus, and Sabethes spp. from 1991-2019 using primary and secondary data sources. Linking these data with selected environmental and land-cover variables, we adopted a stacked regression ensemble modelling approach (elastic-net regularized GLM, extreme gradient boosted regression trees, and random forest) to predict the environmental suitability of these species across Brazil at a 1 km x 1 km resolution. We show that while suitability for each species varies spatially, high suitability for all species was predicted in the Southeastern region where recent outbreaks have occurred. By integrating data on NHP host reservoirs and human populations, our risk maps further highlight municipalities within the region that are prone to transmission and spillover.

CONCLUSIONS/SIGNIFICANCE

Our maps of sylvatic vector suitability can help elucidate potential locations of sylvatic reservoirs and be used as a tool to help mitigate risk of future YF outbreaks and assist in vector surveillance. Furthermore, at-risk regions identified from our work could help disease control and elucidate gaps in vaccination coverage and NHP host surveillance.

Genetic evidence that the Makira region in northeastern Madagascar is a hotspot of malaria transmission

BACKGROUND

Encouraging advances in the control of Plasmodium falciparum malaria have been observed across much of Africa in the past decade. However, regions of high relative prevalence and transmission that remain unaddressed or unrecognized provide a threat to this progress. Difficulties in identifying such localized hotspots include inadequate surveillance, especially in remote regions, and the cost and labor needed to produce direct estimates of transmission. Genetic data can provide a much-needed alternative to such empirical estimates, as the pattern of genetic variation within malaria parasite populations is indicative of the level of local transmission. Here, genetic data were used to provide the first empirical estimates of P. falciparum malaria prevalence and transmission dynamics for the rural, remote Makira region of northeastern Madagascar.

METHODS

Longitudinal surveys of a cohort of 698 total individuals (both sexes, 0-74 years of age) were performed in two communities bordering the Makira Natural Park protected area. Rapid diagnostic tests, with confirmation by molecular methods, were used to estimate P. falciparum prevalence at three seasonal time points separated by 4-month intervals. Genomic loci in a panel of polymorphic, putatively neutral markers were genotyped for 94 P. falciparum infections and used to characterize genetic parameters known to correlate with transmission levels.

RESULTS

Overall, 27.8% of individuals tested positive for P. falciparum over the 10-month course of the study, a rate approximately sevenfold higher than the countrywide average for Madagascar. Among those P. falciparum infections, a high level of genotypic diversity and a high frequency of polygenomic infections (68.1%) were observed, providing a pattern consistent with high and stable transmission.

CONCLUSIONS

Prevalence and genetic diversity data indicate that the Makira region is a hotspot of P. falciparum transmission in Madagascar. This suggests that the area should be highlighted for future interventions and that additional areas of high transmission may be present in ecologically similar regions nearby.