Serological surveillance of healthcare workers to evaluate natural infection- and vaccine-derived immunity to SARS-CoV-2 during an outbreak in Dili, Timor-Leste oleh Paul Arkell, Celia Gusmao, Sarah L Sheridan, Maria Y Tanesi, Nelia Gomes, Tessa Oakley, Johanna Wapling, Lucsendar Alves, Stacey Kopf, Nevio Sarmento, Ismael Da Costa Barreto, Salvador Amaral, Anthony DK Draper, Danina Coelho, Helio Guterres, Antonio Salles, Filipe Machado, Nicholas SS Fancourt, Jennifer Yan, Ian Marr, Kristine Macartney, Joshua R Francis