Biology subjects

Omer, S. B.

Publications and source records attributed to Omer, S. B..

3 recordsLinked to original sources

bioRxiv2021

Adaptive immune determinants of viral clearance and protection in mouse models of SARS-CoV-2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused more than 160 million infections and more than 3 million deaths worldwide. While effective vaccines are currently being deployed, the adaptive immune determinants which promote viral clearance and confer protection remain poorly defined. Using mouse models of SARS-CoV-2, we demonstrate that both humoral and cellular adaptive immunity contributes to viral clearance in the setting of primary infection. Furthermore, we find that either convalescent mice, or mice that receive mRNA vaccination are protected from both homologous infection and infection with a variant of concern, B.1.351. Additionally, we find this protection to be largely mediated by antibody response and not cellular immunity. These results highlight the in vivo protective capacity of antibodies generated to both vaccine and natural infection. One-Sentence SummaryDefining the roles of humoral and cellular adaptive immunity in viral clearance and protection from SARS-CoV-2 and a variant of concern.

immunology↗

bioRxiv2018

Getting personal: how vaccination exemptions shapeherd immunity

BackgroundState-mandated school entry immunization requirements in the United States play an important role in achieving high vaccine coverage and preventing outbreaks of vaccine-preventable diseases. Most states allow non-medical exemptions that let children remain unvaccinated on the basis of personal beliefs. However, the ease of obtaining such exemptions varies, resulting in a patchwork of state vaccination exemption laws, contributing to heterogeneity in vaccine coverage across the country. In this study, we evaluate epidemiological effects and spatial variations in non-medical exemption rates in the context of vaccine policies.\n\nMethods and FindingsWe first analyzed the correlation between non-medical exemption rates and vaccine coverage for three significant childhood vaccinations and found that higher rates of non-medical exemptions were associated with lower vaccination rates of school-aged children in all cases. We then identified a subset of states where exemption policy has recently changed and found that the effects on statewide non-medical exemption rates varied widely. Focusing further on Vermont and California, we illustrated how the decrease in non-medical exemptions due to policy change was concurrent to an increase in medical exemptions (in CA) or religious exemptions (in VT). Finally, a spatial clustering analysis was performed for Connecticut, Illinois, and California, identifying clusters of high non-medical exemption rates in these states before and after a policy change occurred. The clustering analyses show that policy changes affect spatial distribution of non-medical exemptions within a state.\n\nConclusionsOur work suggests that vaccination policies have significant impacts on patterns of herd immunity. Our findings can be used to develop evidence-based vaccine legislation.

epidemiology↗

bioRxiv2018

Feeding the disparities: the geography and trends of breastfeeding in the United States

There is scientific consensus on the importance of breastfeeding for the present and future health of newborns, in high- and low-income settings alike. In the United States, improving breast milk access is a public health priority but analysis of secular trends are largely lacking. Here, we used data from the National Immunization Survey of the CDC, collected between 2003 and 2016, to illustrate the temporal trends and the spatial heterogeneity in breastfeeding. We also considered the effect sizes of two key determinants of breastfeeding rates. We show that, while access to breast milk both at birth and at 6 months old has steadily increased over the past decade, large spatial disparities still remain at the state level. We also find that, since 2009, the proportion of households below the poverty level has become the strongest predictor of breastfeeding rates. We argue that, because variations in breastfeeding rates are associated with socio-economic factors, public health policies advocating for breastfeeding are still needed in particular in underserved communities. This is key to reducing longer term health disparities in the U.S., and more generally in high-income countries.

epidemiology↗