Trends in COVID-19 Incidence After Implementation of Mitigation Measures — Arizona, January 22–August 7, 2020

Abstract

On October 6, 2020, this report was posted as an MMWR Early Release on the MMWR website (https://www.cdc.gov/mmwr). Mitigating the spread of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), requires individual, community, and state public health actions to prevent person-to-person transmission. Community mitigation measures can help slow the spread of COVID-19; these measures include wearing masks, social distancing, reducing the number and size of large gatherings, pausing operation of businesses where maintaining social distancing is challenging, working from or staying at home, and implementing certain workplace and educational institution controls (1-4). The Arizona Department of Health Services' (ADHS) recommendations for mitigating exposure to SARS-CoV-2 were informed by continual monitoring of patient demographics, SARS-CoV-2 community spread, and the pandemic's impacts on hospitals. To assess the effect of mitigation strategies in Arizona, the numbers of daily COVID-19 cases and 7-day moving averages during January 22-August 7, 2020, relative to implementation of enhanced community mitigation measures, were examined. The average number of daily cases increased approximately 151%, from 808 on June 1, 2020 to 2,026 on June 15, 2020 (after stay-at-home order lifted), necessitating increased preventive measures. On June 17, local officials began implementing and enforcing mask wearing (via county and city mandates),* affecting approximately 85% of the state population. Statewide mitigation measures included limitation of public events; closures of bars, gyms, movie theaters, and water parks; reduced restaurant dine-in capacity; and voluntary resident action to stay at home and wear masks (when and where not mandated). The number of COVID-19 cases in Arizona peaked during June 29-July 2, stabilized during July 3-July 12, and further declined by approximately 75% during July 13-August 7. Widespread implementation and enforcement of sustained community mitigation measures informed by state and local officials' continual data monitoring and collaboration can help prevent transmission of SARS-CoV-2 and decrease the numbers of COVID-19 cases. * Mandates and ordinances varied and were county-and city-specific. Enforcement types included educating persons on the dangers of COVID-19 spread, issuing fines to persons and businesses who refused to comply with mandates, and loss of licenses for businesses not enforcing rules or mandates. Public pools (e.g., at hotels; limited capacity) Jun 29, Jul 23 Private pools in public areas (e.g., multihousing complexes; limited capacity) Jun 29, Jul 23 Public events (<50 persons) Mar 15, Jun 29, Jul 23 Wearing masks (mandatory) Local officials able to mandate and enforce wearing masks Jun 17

Trends in County-Level COVID-19 Incidence in Counties With and Without a Mask Mandate — Kansas, June 1–August 23, 2020

“…The findings in this report are consistent with declines in COVID-19 cases observed in 15 states and the District of Columbia, which mandated masks, compared with states that did not have mask mandates ( 7 ). Mask requirements were also implemented as part of a multicomponent approach in Arizona, where COVID-19 incidence stabilized and then decreased after implementation of a combination of voluntary and enforceable community-level mitigation strategies, including mask requirements, limitations on public events, enhanced sanitation practices, and closures of certain services and businesses ( 8 ). The combining of community-level mitigation strategies including physical distancing and enhanced hygiene practices, in addition to consistent and correct use of masks, is a CDC-recommended approach.…”

The role of mask mandates, stay at home orders and school closure in curbing the COVID-19 pandemic prior to vaccination

“…Additionally, they did not adjust for epidemics beginning at different time points in different locations or socio-demographic variables ( 14 ). The studies by Kaufman et al, Chernozhukov et al and Gallaway et al all suggest wearing masks in public locations is beneficial ( 20 , 21 , 23 ).…”

“…Hypothetical mask models support these results and one such study suggested that even weak (ineffective) masks could be useful in curbing disease transmission ( 22 ). It has also been noted that widespread implementation and enforcement of sustained community mitigation measures helped with mitigation of COVID-19, noting a decline in rates once measures were implemented ( 23 ). Similarly, a study looking at daily county-level COVID-19 growth rates in 15 states and Washington, D.C., estimated that more than 200,000 COVID-19 cases could have been averted by May 22, 2020 if utilizing masks in public had been mandatory in all locations ( 24 ).…”

Determinants of COVID-19 preventive behaviours among adults with chronic diseases in the USA: an analysis of the nationally representative COVID-19 impact survey

“…31 32 Our observed geographic disparities in COVID-19 preventive behaviours may also be a reflection of variability in state or local policies regarding COVID-19 preventive behaviours across the individuals residing in US states and counties that have implemented mandatory COVID-19 preventive behaviours, including stay-at-home orders, social distancing and mandatory mask use in public, are more likely to exhibit positive individual-level COVID-19 preventive behaviours. [33][34][35] Inequities in ability or willingness to practice COVID-19 preventive behaviours may lead to inequitable risk and morbidity of COVID-19 among these at-risk groups. Future research should focus on the impact of state-level COVID-19 prevention policies to evaluate area-level differences in individual preventive behaviours and to disentangle whether certain demographics of US adults are either unwilling or unable to adhere to recommended guidelines.…”