High SARS-CoV-2 Seroprevalence and Rapid Neutralizing Antibody Decline among Agricultural Workers in Rural Guatemala, June 2020–March 2021

• Published in: Vaccines (Basel) Vol. 10; no. 7; p. 1160
• Main Authors: Iwamoto, Chelsea, Lesteberg, Kelsey E., Lamb, Molly M., Calvimontes, Diva M., Guo, Kejun, Barrett, Bradley S., Mickens, Kaylee L., Duca, Lindsey M., Monzon, Jose, Chard, Anna N., Guzman, Gerber, Barrios, Edgar, Rojop, Neudy, Arias, Kareen, Gomez, Melissa, Paiz, Claudia, Bolanos, Guillermo Antonio, Edwards, Kathryn M., Zielinski Gutierrez, Emily, Azziz-Baumgartner, Eduardo, Asturias, Edwin J., Santiago, Mario L., Beckham, J. David, Olson, Daniel
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 21.07.2022; MDPI
• Subjects: Agribusiness; agricultural workers; Agriculture; Antibodies; Antigens; cohort; Coronaviruses; Cough; COVID-19; Disease transmission; Employment; Enrollments; Farmworkers; Guatemala; Illnesses; Immunoassay; Immunoglobulin G; Infections; Influenza; Neutralizing; Nucleocapsids; Occupational exposure; Occupational health; Pandemics; Population; Risk analysis; Risk factors; SARS-CoV-2; Serology; seroprevalence; Severe acute respiratory syndrome coronavirus 2; Stability analysis; Vaccination; Workers; Guatemala; COVID-19; Guatemala; seroprevalence; cohort; SARS-CoV-2; agricultural workers
• ISSN: 2076-393X; 2076-393X
• DOI: 10.3390/vaccines10071160

Essential agricultural workers work under occupational conditions that may increase the risk of SARS-CoV-2 exposure and transmission. Data from an agricultural worker cohort in Guatemala, and anti-SARS-CoV-2 nucleocapsid IgG (anti-N IgG) testing were used to estimate past infections and analyze risk factors associated with seropositivity at enrollment and association with SARS-CoV-2 infection. The stability of neutralizing antibody (NAb) responses were assessed in a subset of participants. The adjusted relative risk (aRR) for seroprevalence at enrollment was estimated accounting for correlations within worksites. At enrollment, 616 (46.2%) of 1334 (93.2%) participants had anti-N IgG results indicating prior SARS-CoV-2 infection. A cough ≤ 10 days prior to enrollment (aRR = 1.28, 95% CI: 1.13–1.46) and working as a packer (aRR = 2.00, 95% CI: 1.67–2.38) or packing manager within the plants (aRR = 1.82, 95% CI: 1.36–2.43) were associated with increased risk of seropositivity. COVID-19 incidence density among seronegative workers was 2.3/100 Person-Years (P-Y), higher than seropositive workers (0.4/100 P-Y). Most workers with follow-up NAb testing (65/77, 84%) exhibited a 95% average decrease in NAb titers in <6 months. While participants seropositive at baseline were less likely to experience a symptomatic SARS-CoV-2 infection during follow-up, NAb titers rapidly waned, underscoring the need for multipronged COVID-19 prevention strategies in the workplace, including vaccination.