Hospitalized patients with severe COVID-19 have an increased incidence of insulin resistance, impaired beta cell function, glucose intolerance (prediabetes), and overt type 2 diabetes (T2D) compared to non-hospitalized patients with COVID-19 and COVID-19 negative individuals on long-term follow up.

The purpose of this research study is to understand the long-term effects of COVID-19 infection on individuals without any prior history of diabetes. This study will look at several measures of diabetes, such as glycemic control (blood glucose/sugar levels), function of beta cells (cells that make insulin to control sugar), insulin secretion and insulin sensitivity (fasting insulin levels).

The following participants will be enrolled: 1) have had COVID-19 infection and were hospitalized and recovered, or 2) have had mild COVID-19 infection and were seen at outpatient clinics or ER and were not required to be hospitalized, or 3) have not had COVID-19 infection but were seen in outpatient clinics or ER during the same time period.

The researchers hope to learn the long-term effects of COVID-19 infection in hospitalized patients. Specifically, they will be focusing on the subsequent development of diabetes and associated metabolic disturbances, such as impaired insulin secretion and insulin resistance. A relationship between COVID-19 and diabetes needs to be investigated.

Inclusion Criteria:

• Body Mass index (BMI) < 40 kg/m2

Exclusion Criteria:

• History of diabetes prior to SARS-CoV-2 infection
• Took medications used to treat diabetes prior to SARS-CoV-2 infection
• History of myocardial infarction or stroke within 6 months
• History of major organ system disease prior to COVID-19 infection

Three groups from background (general) population including Mexican ancestry will be studied, who have no history of diabetes or treatment with diabetes drugs prior to COVID-19 infection.