Onchocerciasis is a neglected tropical disease caused by infection with the parasite Onchocerca volvulus (Ov). An estimated 180 million people are at risk for Ov infection, and 37 million people are infected, mostly in Africa. A lateral flow-based assay to detect human IgG4 antibodies to the Ov-specific antigen Ov-16 was developed as a rapid tool to detect exposure to Ov. The test, when performed on 449 sera specimens from patients with microfiladermia and Ov-negative patients, has a sensitivity of 89.1% (95% confidence interval: 86.2%–92.0%), and specificity of 97% (95% confidence interval: 95.4%–98.6%). Because the intended use of the test is for surveillance, it is highly desirable to have a stable, long-lasting result. An extended read window is thus desirable for a high-volume, busy workflow and facilitates post-surveillance quality assurance. The main restriction on achieving an extended read window for this assay was the erythrocyte lysis that can alter the signal-to-noise ratio, especially in those with low IgG4 levels (weak positives). We describe a test housing that incorporates a user-independent feature driven by assay fluid and an expanding wick that detaches the blood separation membrane from the nitrocellulose used in the assay, but before hemolysis occurs. We demonstrated material functionality at extreme operational conditions (37°C, 80% relative humidity) and a read window of a minimum of 70 days. The fluid-driven assay device performs equally as well with whole blood as with plasma, as demonstrated with 100 spiked clinical specimens (with a correlation coefficient of 0.96). We show a novel, inexpensive, and simple approach to actuating the detachment of the blood separation membrane from the nitrocellulose test with no impact on the performance characteristics of the test.

Background/Objective: Older adults are at risk for tooth loss and compromised nutritional status. Our objective was to conduct a systematic review and meta-analysis to answer the following question: Among adults aged ≥60 y living in developed countries, what are the associations between tooth loss and nutritional status as assessed by a validated nutrition screening or assessment tool? Methods: PRISMA guidelines were followed. PubMed, Scopus, CINAHL, Web of Science, and MEDLINE were searched for studies published in English between 2009 and 2019 that met inclusion criteria. Data extracted included study and participant characteristics, dentition, and nutritional status. Risk of bias was assessed with a modified Newcastle-Ottawa Scale. Random effects meta-analysis was used. Results: Of the 588 unduplicated articles identified, 78 were reviewed in full text, and 7 met inclusion criteria. Six studies were combined for a meta-analysis, which revealed that individuals who were completely edentulous or who lacked functional dentition had a 21% increased likelihood of being at risk of malnutrition or being malnourished, as compared with those who were dentulous or had functionally adequate dentition (risk ratio, 1.21; 95% CI, 1.11 to 1.32; I2 = 70%). Whether the article statistically adjusted for medical history explained most of the heterogeneity in the pooled effect. Conclusions and Implications: Findings suggest that older adults with tooth loss are at greater risk of malnutrition than those with functionally adequate dentition. Use of validated tools to assess risk of malnutrition in older adults with tooth loss is important to promote early intervention and referral to optimize nutrition and oral health status. Findings were limited by heterogeneity, risk of bias, and overall quality of the studies reviewed. Cohort studies that adjust for known confounders and use consistent approaches to assess tooth loss and nutritional status are needed. Knowledge Transfer Statement: The results of this study suggest that older adults with tooth loss are at greater risk of malnutrition than those with functionally adequate dentition. Screening of this population for malnutrition by health care professionals, including dentists and dietitians, may result in corresponding referrals to optimize nutrition and oral health status. Further research is needed with consistent approaches to assess tooth loss and nutritional status.

In the past few years, efforts to eliminate onchocerciasis from Africa have intensified. These efforts are primarily based on the mass distribution of the anti-helminthic drug Mectizan™ (ivermectin). This program has led to the development of new guidelines by the World Health Organization for the verification that transmission has been suppressed and eventually eliminated. The requirements of diagnostic tools for this purpose differ in many ways from tests used to diagnose infection in individuals. In this review, we summarize the progress that has been made to identify diagnostics that meet the specialized requirements needed to verify onchocerciasis elimination, discuss why these tests were selected and summarize the needs that still exist to complete the arsenal of diagnostic tools that will be useful as the goal of elimination is achieved.

Elimination programs for Wuchereria bancrofti and Onchocerca volvulus are in critical need of sensitive, specific, and point-ofcontact (POC) tools that can be used for surveillance years beyond cessation of mass drug administration when infection intensities are low. Previously, Wb123 and Ov16 were identified individually as potential filarial antigens for an antibody-based POC test. The present study compares single-antigen Wb123-and Ov16-based POC tests with an integrated configuration to detect antibodies to Wb123 and Ov16 simultaneously. Wb123 and Ov16 isolates were striped onto lateral flow strips containing antiIgG4. Sera from W. bancrofti-, O. volvulus-, and other helminth-infected or -uninfected individuals were added to the strips with buffer. Strips were read for the appearance of a positive or negative test line for both antigens at 20 min and following drying. Sensitivity, specificity, and predictive values were calculated for the single-antigen and biplex strips. Single and biplex lateral flow strips showed nearly identical results, with >90% sensitivity for Ov16 and >92% sensitivity for Wb123. Overall specificities for the single and biplex tests were 98% and 96% for Ov16 and Wb123, respectively. Biplex tests performed as well as the singleantigen tests regardless of the intensity of patient IgG4 response. The high sensitivity and specificity make these new biplex tests extremely useful for POC long-term surveillance following mass drug administration in Africa that should reduce time and cost in areas where bancroftian filariasis and onchocerciasis are coendemic.

bThe Global Programme to Eliminate Lymphatic Filariasis has an urgent need for rapid assays to detect ongoing transmission of lymphatic filariasis (LF) following multiple rounds of mass drug administration (MDA). Current WHO guidelines support using the antigen card immunochromatographic test (ICT), which detects active filarial infection but does not detect early exposure to LF. Recent studies found that antibody-based assays better serve this function. In the present study, two tests, a rapid IgG4 enzyme-linked immunosorbent assay (ELISA) and a lateral-flow strip immunoassay, were developed based on the highly sensitive and specific Wuchereria bancrofti antigen Wb123. A comparison of W. bancrofti-infected and -uninfected patients (with or without other helminth infections) demonstrated that both tests had high sensitivities and specificities (93 and 97% [ELISA] and 92 and 96% [strips], respectively). When the W. bancrofti-uninfected group was separated into those with other filarial/helminth infections (i.e., onchocerciasis, loiasis, and strongyloidiasis) and those who were parasite uninfected, the specificities of the assays varied between 91 and 100%. In addition, the geometric mean response by ELISA of W. bancrofti-infected patients was significantly higher than the response of those without W. bancrofti infection (P < 0.0001). Furthermore, the Wb123 ELISA and the lateral-flow strips had high positive and negative predictive values, giving valuable information on the size of survey population needed to be reasonably certain whether or not transmission is ongoing. These highly sensitive and specific IgG4 tests to the W. bancrofti Wb123 protein give every indication that they will serve as useful tools for post-MDA monitoring.