Post-campaign coverage evaluation of a measles and rubella supplementary immunization activity in five districts in India, 2019-2020.

BACKGROUND: In alignment with the Measles and Rubella (MR) Strategic Elimination plan, India conducted a mass measles and rubella vaccination campaign across the country between 2017 and 2020 to provide a dose of MR containing vaccine to all children aged 9 months to 15 years. We estimated campaign vaccination coverage in five districts in India and assessed campaign awareness and factors associated with vaccination during the campaign to better understand reasons for not receiving the dose. METHODS AND FINDINGS: Community-based cross-sectional serosurveys were conducted in five districts of India among children aged 9 months to 15 years after the vaccination campaign. Campaign coverage was estimated based on home-based immunization record or caregiver recall. Campaign coverage was stratified by child- and household-level risk factors and descriptive analyses were performed to assess reasons for not receiving the campaign dose. Three thousand three hundred and fifty-seven children aged 9 months to 15 years at the time of the campaign were enrolled. Campaign coverage among children aged 9 months to 5 years documented or by recall ranged from 74.2% in Kanpur Nagar District to 90.4% in Dibrugarh District, Assam. Similar coverage was observed for older children. Caregiver awareness of the campaign varied from 88.3% in Hoshiarpur District, Punjab to 97.6% in Dibrugarh District, Assam, although 8% of children whose caregivers were aware of the campaign were not vaccinated during the campaign. Failure to receive the campaign dose was associated with urban settings, low maternal education, and lack of school attendance although the associations varied by district. CONCLUSION: Awareness of the MR vaccination campaign was high; however, campaign coverage varied by district and did not reach the elimination target of 95% coverage in any of the districts studied. Areas with lower coverage among younger children must be prioritized by strengthening the routine immunization programme and implementing strategies to identify and reach under-vaccinated children.

Human solid tumors and clinical relevance of the enhanced permeation and retention effect: a 'golden gate' for nanomedicine in preclinical studies?

Nanocarriers passively accumulate in solid tumors through irregular wide fenestrations in neovasculature and increased retention due to poor lymphatic drainage, a phenomenon termed the enhanced permeation and retention (EPR) effect. Although several preclinical reports have described the role of EPR in nanomedicine, its role in human solid tumor is obscure. There are several distinct factors for tumors in mice versus humans, including size, heterogeneity and nanomedicine pharmacokinetics. This review focuses on preclinical and clinical studies demonstrating the role of the EPR effect and passive targeting. The article illustrates the gaps that limit clinical effectiveness of the EPR effect and elaborates strategies to boost its efficiency, relaying future clinical outcomes for designing clinically applicable EPR-based nanomedicine.

Unlike healthy organ vasculature in organs, solid tumor vasculature is leaky with poor lymphatic drainage. Nanoparticles <200 nm are reported to be selectively taken up in the tumor due to this tumor physiology, a process referred to as the enhanced permeation and retention (EPR) effect. Despite lots of preclinical evidence, there is lack of clinical success observed for EPR effect in human tumors. There are several factors responsible for this poor preclinical to clinical rendition of nanomedicine delivery to tumors by EPR effect. We have highlighted key differences between murine and human tumor models as well as listed effective approaches to boost the EPR effect in nanomedicine. These strategies will bridge the gaps that limit clinical translation of EPR-based nanomedicine and lay the groundwork to design effective anticancer therapies.

Evaluating the effect of measles and rubella mass vaccination campaigns on seroprevalence in India: a before-and-after cross-sectional household serosurvey in four districts, 2018-2020.

BACKGROUND: India did phased measles-rubella supplementary immunisation activities (MR-SIAs; ie, mass-immunisation campaigns) targeting children aged 9 months to less than 15 years. We estimated measles-rubella seroprevalence before and after the MR-SIAs to quantify the effect on population immunity and identify remaining immunity gaps. METHODS: Between March 9, 2018 and March 19, 2020 we did community-based, cross-sectional serosurveys in four districts in India before and after MR-SIAs. 30 villages or wards were selected within each district, and one census enumeration block from each was selected as the survey cluster. Households were enumerated and 13 children in the younger age group (9 months to <5 years) and 13 children in the older ager group (5 to <15 years) were randomly selected by use of computer-generated random numbers. Serum samples were tested for IgG antibodies to measles and rubella viruses by enzyme immunoassay. FINDINGS: Specimens were collected from 2570 children before the MR-SIA and from 2619 children afterwards. The weighted MR-SIA coverage ranged from 73·7% to 90·5% in younger children and from 73·6% to 93·6% in older children. Before the MR-SIA, district-level measles seroprevalence was between 80·7% and 88·5% among younger children in all districts, and between 63·4% and 84·5% among older children. After the MR-SIA, measles seroprevalence among younger children increased to more than 90% (range 91·5 to 96·0) in all districts except Kanpur Nagar, in which it remained unchanged 80·4%. Among older children, measles seroprevalence increased to more than 90·0% (range 93·7% to 96·5%) in all districts except Hoshiarpur (88·7%). A significant increase in rubella seroprevalence was observed in all districts in both age groups, with the largest effect in Dibrugarh, where rubella seroprevalence increased from 10·6% to 96·5% among younger children. INTERPRETATION: Measles-rubella seroprevalence increased substantially after the MR-SIAs but the serosurvey also identified remaining gaps in population immunity. FUNDING: The Bill & Melinda Gates Foundation and Indian Council of Medical Research.