Latin America accounts for roughly one-quarter of global COVID-19 cases and one-third of deaths. Health inequalities in the region lead to barriers regarding the best use of diagnostic tests during the pandemic. There is a need for a simplified guideline in the region that takes into consideration the available health resources, international guidelines, medical literature, and local expertise.

Nine experts from different Latin American countries developed a simplified algorithm for COVID-19 diagnosis in the region, using a modified Delphi method. Twenty-four questions related to diverse diagnostic settings were initially proposed, followed by an extensive discussion of the literature and experts' experience.

According to time from close contact or symptom onset, the algorithm considers three different timeframes (≤7 days, 8–13 days, and ≥14 days) and discusses diagnostic options for each one. SARS-CoV-2 real-time reverse transcription polymerase chain reaction (rRT-PCR) continues to be the diagnostic test of choice from Day 1 to Day 14 after symptom onset or close contact, although antigen testing may be used in high-prevalence settings or in particular situations (such as from Day 0 to Days 5–7 of symptom onset). Antibody assays may be used for diagnostic confirmation, mainly after Day 14, if there is an epidemiological or individual need. If the clinical suspicion is very high, but other tests are negative, these assays may be used as an adjunct to decision-making from Days 8–13.

The proposed algorithm is intended to be used as a support for COVID-19 diagnosis decision-making in Latin America.