Highlights We nested a measles and rubella serological survey in a vaccination coverage survey. Measles and rubella immunity was significantly higher than expected by vaccination. Study revealed immunity gap in young adults and risk of congenital rubella syndrome. Adding serology to a survey leveraged resources and provided complementary information.

Diagnosis of asymptomatic malaria poses a great challenge to global disease elimination efforts. Healthcare infrastructure in rural settings cannot support existing state-of-the-art tools necessary to diagnose asymptomatic malaria infections. Instead, lateral flow immunoassays (LFAs) are widely used as a diagnostic tool in malaria endemic areas. While LFAs are simple and easy to use, they are unable to detect low levels of parasite infection. We have developed a field deployable Magnetically-enabled Biomarker Extraction And Delivery System (mBEADS) that significantly improves limits of detection for several commercially available LFAs. Integration of mBEADS with leading commercial Plasmodium falciparum malaria LFAs improves detection limits to encompass an estimated 95% of the disease reservoir. This user-centered mBEADS platform makes significant improvements to a previously cumbersome malaria biomarker enrichment strategy by improving reagent stability, decreasing the processing time 10-fold, and reducing the assay cost 10-fold. The resulting mBEADS process adds just three minutes and less than $0.25 to the total cost of a single LFA, thus balancing sensitivity and practicality to align with the World Health Organization’s ASSURED criteria for point-of-care (POC) testing.

Background Measles and congenital rubella syndrome remain significant causes of morbidity and mortality despite available vaccines. HIV-infected youth may be at increased risk of measles because of greater waning immunity following vaccination. At a population level, they constitute a potentially large pool of susceptibles to measles and rubella. More data among HIV-infected youth in sub-Saharan Africa are needed to guide vaccination policy and control strategies. Methods This cross-sectional study was nested within two ongoing studies of malaria and HIV in Zambia. Dried blood spot cards from youth (5–15 years) in these studies from 2009–2013 were tested for IgG antibodies to measles and rubella viruses. HIV-uninfected youth, HIV-infected treatment-naïve youth, and HIV-infected youth receiving antiretroviral therapy (ART) were compared. Results 617 HIV-uninfected, 144 HIV-infected treatment-naïve, and 128 HIV-infected youth receiving ART were included in the study. The proportion seropositive for measles virus was significantly higher among HIV-uninfected youth (92.5%) compared to HIV-infected treatment-naïve youth (74.1%) and HIV-infected youth receiving ART (71.9%). No differences by age were observed. The proportion seropositive for rubella virus was significantly higher among HIV-uninfected youth (54.7%) compared with HIV-infected treatment-naïve youth (41.7%) and HIV-infected youth receiving ART (49.6%), with increases observed by age for all groups. Conclusions Measles seroprevalence was lower among HIV-infected than uninfected youth, consistent with waning immunity following measles vaccination. HIV-infected youth would likely benefit from revaccination. Half of all youth in rural Zambia were susceptible to rubella and may need targeting for catch-up rubella campaigns when measles-rubella vaccine is introduced.