Seroprevalence of SARS-CoV-2 infection in the general population of Nepal during the first and second generalized waves of the COVID-19 pandemic-2020-2021.

Few seroprevalence studies have been conducted on coronavirus disease (COVID-19) in Nepal. Here, we aimed to estimate seroprevalence and assess risk factors for infection in the general population of Nepal by conducting two rounds of sampling. The first round was in October 2020, at the peak of the first generalized wave of COVID-19, and the second round in July-August 2021, following the peak of the wave caused by the delta variant of SARS-CoV-2. We used cross-sectional probability-to-size (PPS)-based multistage cluster sampling to estimate the seroprevalence in the general population of Nepal at the national and provincial levels. We tested for anti-SARS-CoV-2 total antibody using the WANTAI SARS-CoV-2 Ab ELISA kit. In Round 1, the overall national seroprevalence was 14.4%, with provincial estimates ranging from 5.3% in Sudurpaschim to 27.3% in Madhesh Province. In Round 2, the estimated national seroprevalence was 70.7%, with the highest in the Madhesh Province (84.8%) and the lowest in the Gandaki Province (62.9%). Seroprevalence was comparable between males and females (Round 1, 15.8% vs. 12.2% and Round 2, 72.3% vs. 68.7%). The seroprevalence in the ecozones-Terai, hills, and mountains-was 76.3%, 65.3%, and 60.5% in Round 2 and 17.7%, 11.7%, and 4.6% in Round 1, respectively. In Nepal, COVID-19 vaccination was introduced in January 2021. At the peak of the first generalized wave of COVID-19, most of the population of Nepal remained unexposed to SARS-CoV-2. Towards the end of the second generalized wave in April 2021, two thirds of the population was exposed.

Sensor-as-a-Service: Convergence of Sensor Analytic Point Solutions (SNAPS) and Pay-A-Penny-Per-Use (PAPPU) Paradigm as a Catalyst for Democratization of Healthcare in Underserved Communities.

In this manuscript, we discuss relevant socioeconomic factors for developing and implementing sensor analytic point solutions (SNAPS) as point-of-care tools to serve impoverished communities. The distinct economic, environmental, cultural, and ethical paradigms that affect economically disadvantaged users add complexity to the process of technology development and deployment beyond the science and engineering issues. We begin by contextualizing the environmental burden of disease in select low-income regions around the world, including environmental hazards at work, home, and the broader community environment, where SNAPS may be helpful in the prevention and mitigation of human exposure to harmful biological vectors and chemical agents. We offer examples of SNAPS designed for economically disadvantaged users, specifically for supporting decision-making in cases of tuberculosis (TB) infection and mercury exposure. We follow-up by discussing the economic challenges that are involved in the phased implementation of diagnostic tools in low-income markets and describe a micropayment-based systems-as-a-service approach (pay-a-penny-per-use-PAPPU), which may be catalytic for the adoption of low-end, low-margin, low-research, and the development SNAPS. Finally, we provide some insights into the social and ethical considerations for the assimilation of SNAPS to improve health outcomes in marginalized communities.

Nanoparticle-Based Biosensing of Tuberculosis, an Affordable and Practical Alternative to Current Methods.

Access to community-based point-of-care, low-cost, and sensitive tuberculosis (TB) diagnostics remains an unmet need. OBJECTIVE: The objective of this study was to combine principles in nanotechnology, TB biology, glycochemistry, and engineering, for the development of a nanoparticle-based colorimetric biosensing assay (NCBA) to quickly and inexpensively detect acid-fast bacilli (AFB) in sputum samples. METHODS: In NCBA, the isolation of AFB from sputum samples was accomplished through glycan-coated magnetic nanoparticles (GMNP) interacting with AFB and then using a simple magnet to separate the GMNP-AFB complex. Acid-fastness and cording properties of mycobacteria were utilized to provide visually observable red-stained clumps of bacteria that were surrounded by brown nanoparticles under a light microscope on prepared smears. The NCBA technique was compared against sputum smear microscopy (SSM) and Xpert MTB/RIF in 500 samples from patients that were suspected to have TB. RESULTS: Statistical analysis showed that NCBA had sensitivity and specificity performances in perfect agreement with Xpert MTB/RIF as gold standard for all 500 samples. SSM had a sensitivity of 40% for the same samples. CONCLUSION: NCBA technique yielded full agreement in terms of sensitivity and specificity with the Xpert MTB/RIF in 500 samples. The method is completed in 10⁻20 min through a simple process at an estimated cost of $0.10 per test. Implementation of NCBA in rural communities would help to increase case finding and case notification, and would support programs against drug-resistance. Its use at the first point-of-contact by patients in the healthcare system would facilitate quick treatment in a single clinical encounter, thus supporting the global "End TB Strategy" by 2035.

Prevalence of HIV-1 Subtypes and Antiretroviral Drug Resistance Mutations in Nepal.

BACKGROUND: There have been very few reports of HIV-1 subtypes and drug resistance mutations (DRMs) from Nepal which is geographically located between two high-prevalence HIV-1 infection countries, China and India. OBJECTIVE: The aim of this study was to determine prevalence of acquired and transmitted DRMs and HIV-1 subtypes in Nepal. METHODS: Thirty-five HIV-1 seropositive samples from central region of Nepal were collected in 2011. The subjects were divided into two groups, antiretroviral (ARV) drug naïve group (n=15) and antiretroviral treatment (ART) group (n=20), 90% (18/20) of them received zidovudine, lamivudine and nevirapine (AZT/3TC/NVP) regimen. HIV pol (protease and reverse transcriptase regions) nucleotide sequences were analyzed by Viroseq HIV-1 Genotyping System. Nearly full-length genomic (NFLG) sequences of 10 samples were performed. RESULTS: NFLG genotyping revealed that 80% of samples were infected with subtype C and 20% with recombinants (C/D/H and C/A). Phylogenetic analysis of 35 pol sequences from Nepal were subtype C. The prevalence of acquired DRMs to NNRTIs and NRTIs was 15% (3/20). DRMs to NVP, K103N and V179D, and to NRTIs were observed at 11.1% (2/18) and 5% (1/20), respectively. The prevalence of DRMs to rilpivirine for E138A/G was 5.7%. The minor protease inhibitors (PI) associated mutations (A71T/V and T74S) were observed in 5/35 (14.3%) subjects. CONCLUSION: This is the first report of NFLG HIV-1 genomic sequences and DRMs from Nepal. National surveillance of HIV DRMs to ARVs and molecular epidemiology study should be done annually for better prevention and treatment of HIV infection in Nepal.