1. World Health Organization. Coronavirus (COVID-19) Dashboard. Available from: https://covid19.who.int. Accessed July 21, 2021.
2. United States COVID-19 cases, deaths, and laboratory testing (NAATs) by state, territory, and jurisdiction. Available from: https://covid.cdc.gov/covid-data-tracker/?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fcoronavirus%2F2019-ncov%2Fcases-updates%2Fcases-in-us.html#cases_totalcases. Accessed July 21, 2021.
3. COVID data tracker weekly review, CDC. Available from: https://covid.cdc.gov/covid-data-tracker/#vaccination-trends_vacctrends-fully-daily. Accessed August 21, 2021.
4. Covid-19: Cases of delta variant rise by 79%, but rate of growth slows