ABSTRACT
BackgroundEarly in the SARS-CoV-2 pandemic, many national public health authorities implemented non-pharmaceutical interventions to mitigate disease outbreaks. Panama established mandatory mask use two months after its first documented case. Initial compliance was high, but diverse masks were used in public areas. We studied behavioral dynamics of mask use through the first two COVID waves in Panama, to improve implementation of effective, low-cost public health containment measures, when populations are exposed to novel air-borne pathogens. MethodsMask use behavior was recorded from pedestrians in four Panamanian populations (August to December 2020). We recorded facial coverings; and if used, the type of mask, and gender and estimated age of the wearer. FindingsPeople were highly compliant (> 95%) with mask mandates, and demonstrated important population-level behaviours: 1) decreasing use of cloth masks over time, and increasing use of surgical masks; 2) mask use was 3-fold lower in sub-urban neighborhoods than other public areas; and 3) young people were least likely to wear masks. InterpretationResults help focus highly-effective, low-cost, public health interventions for managing and controlling a pandemic. Considerations of behavioural preferences for different masks, relative to pricing and availability, are essential for optimizing public health policies. Policies to increase availability of effective masks, and behavioral nudges to increase acceptance, and to facilitate mask usage, during the on-going SARS-CoV-2 pandemic, and for future pandemics of respiratory pathogens, are key tools, especially for nations lagging in access to expensive vaccines and pharmacological approaches. Funding11-2020 SNI Grant, SENACYT.
ABSTRACT
Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic, which has reached 28 million cases worldwide in eight months. The serological detection of antibodies against the virus will play a pivotal role in complementing molecular tests to improve diagnostic accuracy, contact tracing, vaccine efficacy testing and seroprevalence surveillance. Here, we aimed first to evaluate a lateral flow assays ability to identify specific IgM and IgG antibodies against SARS-CoV-2 and second, to report the seroprevalence of these antibodies among health care workers and healthy volunteer blood donors in Panama. We recruited study participants between April 30th and July 7th, 2020. For the test validation and performance evaluation, we analyzed serum samples from participants with clinical symptoms and confirmed positive RT-PCR for SARS-CoV-2, participants with other confirmed infectious diseases, and a set of pre-pandemic serum samples. We used two by two table analysis to determine the test sensitivity and specificity as well as the kappa agreement value with a 95% confidence interval. Then, we used the lateral flow assay to determine seroprevalence among serum samples from COVID-19 patients, potentially exposed health care workers, and healthy volunteer donors. Our results show this assay reached a positive percent agreement of 97.2% (95% CI 84.2-100.0%) for detecting both IgM and IgG. The assay showed a kappa of 0.898 (95%CI 0.811-0.985) and 0.918 (95% CI 0.839-0.997) for IgM and IgG, respectively. The evaluation of serum samples from hospitalized COVID-19 patients indicates a correlation between test sensitivity and the number of days since symptom onset; the highest positive percent agreement (87% (95% CI 67.0-96.3%)) was observed at [≥]15 days post-symptom onset. We found an overall antibody seroprevalence of 11.6% (95% CI 8.5-15.8%) among both health care workers and healthy blood donors. Our findings suggest this lateral flow assay could contribute significantly to implementing seroprevalence testing in locations with active community transmission of SARS-CoV-2.