Increased mask adherence after important politician infected with COVID-19.

OBJECTIVES: To quantify changes in adherence to mask and distancing guidelines in outdoor settings in Philadelphia, PA before and after President Trump announced he was infected with COVID-19.
METHODS: We used Systematic Observation of Masking Adherence and Distancing (SOMAD) to assess mask adherence in parks, playgrounds, and commercial streets in the 10 City Council districts in Philadelphia PA. We compared adherence rates between August and September 2020 and after October 2, 2020.
RESULTS: Disparities in mask adherence existed by age group, gender, and race/ethnicity, with females wearing masks correctly more often than males, seniors having higher mask use than other age groups, and Asians having higher adherence than other race/ethnicities. Correct mask use did not increase after the City released additional mask guidance in September but did after Oct 2. Incorrect mask use also decreased, but the percentage not having masks at all was unchanged.
CONCLUSIONS: Vulnerability of leadership appears to influence population behavior. Public health departments likely need more resources to effectively and persuasively communicate critical safety messages related to COVID-19 transmission.

Introduction

Prior to widespread vaccine availability, the only way to prevent the spread of COVID-19 was by wearing a mask, maintaining a physical distance of at least six feet from others, and frequent handwashing. Multiple modeling studies of the spread of COVID-19 support the importance of wearing masks and maintaining a physical distance from others [1-4]. One modeling study suggested that 80% compliance with mask wearing would reduce mortality from COVID-19 by up to 45% [2], and it has been suggested that masks may reduce the size of the inoculum, leading to milder infections [5].

The science demonstrating the effectiveness of masking is very strong [6], yet this protective behavior has become politicized. Some consider mandates to wear masks a violation of individual freedom. In spite of the persistent spread of the infection and an increasing death tally in countries like Brazil and the United States, many do not wear masks in public settings. In countries like South Korea, Japan and China, where adherence to masking mandates were high, the case rates were considerably lower than in the US and Brazil [7].

Understanding adherence to mask and distancing guidelines may be critical to controlling disease spread in the absence of a vaccine or if a large proposal of the population refuses to accept vaccination. Most studies on adherence rely on either modeling [1-4], documenting the presence or absence of policies [8-10], or self-report [11]. Direct observation has repeatedly been demonstrated to be a reliable method of measuring a variety of individual characteristics and behaviors, including the intensity of physical activity and human interactions [12-14]. The technique entails data collectors recording a limited number of visible characteristics of the individuals they observe. Respondent burden and reactivity are both eliminated as observers do not interact with subjects. When conducted in public settings, systematic observations studies are generally categorized as exempt by human subjects’ protection committees.

Given the controversy about mask use, we wondered whether President Trump’s COVID-19 infection might influence adherence to recommendations to wear masks in public settings. We capitalized on our ongoing surveillance of mask wearing in Philadelphia, the city where most of our staff are located, to determine whether adherence changed after the President reported his disease state. Understanding which factors promote better adherence to masking and distancing guidelines is critical for controlling virus spread.

Methods

We employed Systematic Observation of Mask Adherence and Distancing (SOMAD), a direct observation tool to document the number of people wearing masks correctly and keeping at least six feet away from others. The reliability of SOMAD was assessed to have less than 10% measurement errors for each variable between two independent observers and less than 1.2% when aggregated by day [14]. (The tool is available on https://www.kp-scalresearch.org/somad/).

Observations were conducted in parks, playgrounds, and commercial streets in each of Philadelphia’s 10 City Council districts, a total of 30 sites. Locations were chosen based on their having a high number of people passing through the areas under observation. Each site was observed for one hour on both a weekday and a weekend day, with each observed at the same time of day on each occasion for a total of 60 observation hours in August and another 60 hours between September 23 and October 11, 2020. Trained data collectors observed individuals in these settings, recording their characteristics and behaviors including: age group (infant/toddler ages 0–2), child (3–12), teen (13–19), adult (20–59), and senior (> = 60); gender; apparent race/ethnicity (white, black, Asian, Latino, undetermined), and mask adherence (correct use; incorrect use, but mask visible; no mask). Correct mask use was defined as having the mask covering both mouth and nose. Incorrect use was defined as either mouth or nose exposed. We also collected information simultaneously on each person’s physical activity level (sedentary, moderate, and vigorous), mode of transport (on wheels or not), group size (alone, 2, 3–5, 6–9, 10+), and physical distancing (>6 feet from others or not). At each location observers noted whether there was crowding, defined as having more people than would make it possible to stay at least 6 feet apart from others. All data were entered using a Google form. Given observers did not interact with human subjects, the study was deemed exempt by the RAND IRB.

Observations took place between August 11 and August 30, 2020 and between September 23 and October 11, 2020. We compared mask adherence in August and September and after October 2, 2020, the date the President’s COVID-19 infection was made public. Our analysis includes descriptive statistics as well as a Generalized Estimating Equations (GEE) model controlling for all the eight individual variables observed, as well as the setting, population density, percentage of households in poverty in the council district, and the time of the observation.

Results

During August 2020 we observed 4606 individuals across the 30 locations. Overall, 43.2% wore it correctly, 16.7% wore it incorrectly, and 40.2% did not wear a mask at all. (See Table 1). Patterns of disparities in correct mask use persisted over time. From August through the beginning of October females had higher correct mask usage than males (58.7% vs. 45.3%, p < .0001); among the four age groups seniors had the highest correct use (57.8%) while teens had only 37.5% correct use (p < .0001); Asians had the highest adherence among racial/ethnic groups (60.3%) and Hispanic/Latinex the lowest (38.2%) (P < .0001).

Table 1

Mask use adherence before and after Oct 2, 2020, Philadelphia PA.

	Before 02 October 2020					02 October 2020 and after
	N	Overall	Mask Correct	Mask Incorrect Visible	No Mask Seen	N	Overall	Mask Correct	Mask Incorrect Visible	No Mask Seen	P value comparing before/after Oct 2
(N)	2641		1166	507	968	2473		1272	239	962
Overall Mask use			44.1%	19.2%	36.7%			51.4%	9.7%	38.9%	< .0001
Gender
Male	1399	54.1%	38.7%	19.4%	41.9%	1325	53.6%	45.3%	9.8%	44.9%	< .0001
Female	1168	45.2%	50.6%	18.1%	31.3%	1144	46.3%	58.7%	9.5%	31.7%	< .0001
Non-Binary/Unknown	18	0.7%	11.1%	33.3%	55.6%	4	0.2%	0.0%	0.0%	100.0%	0.2474
Age Group
Toddler	93	3.5%	7.5%	2.2%	90.3%	59	2.4%	11.9%	0.0%	88.1%	0.3632
Child	271	10.3%	34.3%	9.6%	56.1%	233	9.5%	42.1%	5.6%	52.4%	0.0858
Teen	100	3.8%	42.0%	15.0%	43.0%	120	4.9%	37.5%	12.5%	50.0%	0.5769
Adult	1885	71.7%	46.9%	20.9%	32.1%	1791	72.8%	54.1%	9.9%	36.0%	< .0001
Senior	279	10.6%	49.1%	22.6%	28.3%	256	10.4%	57.8%	11.3%	30.9%	0.0025
Race/ethnicity
Non-Hispanic White	1419	55.1%	46.4%	10.9%	42.6%	1422	57.6%	56.7%	6.5%	36.8%	< .0001
Non-Hispanic Black/African American	771	29.9%	40.7%	31.3%	28.0%	812	32.9%	42.5%	14.5%	43.0%	< .0001
Non-Hispanic Asian	151	5.9%	64.9%	19.2%	15.9%	121	4.9%	60.3%	5.8%	33.9%	< .0001
Hispanic/Latinx	221	8.6%	24.9%	24.9%	50.2%	110	4.5%	38.2%	18.2%	43.6%	0.0378
Unknown/unable to determine	15	0.6%	33.3%	40.0%	26.7%	5	0.2%	60.0%	20.0%	20.0%	0.5594
Activity level
Sedentary	218	8.3%	26.6%	28.4%	45.0%	183	7.4%	23.5%	9.8%	66.7%	< .0001
Moderate	2282	86.4%	47.9%	17.5%	34.6%	2184	88.3%	54.7%	9.8%	35.5%	< .0001
Vigorous	141	5.3%	11.3%	31.9%	56.7%	106	4.3%	33.0%	6.6%	60.4%	< .0001
Transportation mode
On wheels	210	8.3%	23.8%	10.0%	66.2%	194	7.9%	29.4%	3.6%	67.0%	0.0282
Not on wheels	2327	91.7%	47.2%	17.4%	35.5%	2268	92.1%	53.4%	10.2%	36.4%	< .0001
Group size
Not in a group	1180	45.6%	43.7%	21.9%	34.3%	1111	45.0%	54.0%	10.4%	35.6%	< .0001
group of 2	673	26.0%	50.5%	18.1%	31.4%	799	32.3%	51.4%	8.8%	39.8%	< .0001
group of 3 to 5	555	21.5%	43.4%	11.9%	44.7%	517	20.9%	49.1%	8.9%	42.0%	0.0984
group of 6 to 9	135	5.2%	22.2%	20.0%	57.8%	25	1.0%	20.0%	24.0%	56.0%	0.8946
group of 10 or more	43	1.7%	11.6%	44.2%	44.2%	19	0.8%	0.0%	5.3%	94.7%	0.0009
Keep > 6ft distance from others
Yes	1224	46.8%	44.0%	21.2%	34.8%	1202	48.8%	51.7%	10.1%	38.1%	< .0001
No	1394	53.3%	44.8%	16.6%	38.7%	1259	51.2%	51.0%	9.1%	40.0%	< .0001
Setting
Commercial Street	1176	44.5%	48.2%	27.0%	24.7%	1266	51.2%	60.8%	11.1%	28.0%	< .0001
Neighborhood Park	925	35.0%	40.3%	15.0%	44.6%	831	33.6%	49.3%	8.4%	42.2%	< .0001
Playground	540	20.5%	41.9%	9.3%	48.9%	376	15.2%	24.5%	7.4%	68.1%	< .0001

Between September 23 and October 1, of 2641 people observed, 36.7% did not wear a mask, 44.1% wore it correctly, and 19.2% wore it incorrectly, a non-significant change from August, 2020 (p = .31). However, from October 2 through October 11, of 2473 observed, correct mask use increased to 51.4% while incorrect use dropped to 9.7% (p < .0001). Correct mask use was observed among males (17%), females (16%), younger adults (15%), seniors (18%), whites (24%), and those categorized as Latinx (53%). (See Table 1).

After controlling for individual characteristics, time and setting variables, multiple differences in mask adherence were seen (Table 2). Across age groups, senior used masks correctly the most. Females used them more than males and Asians wore masks correctly more often than all other racial/ethnic groups. Those engaged in moderate physical activity wore masks correctly more often than those who were sedentary or in vigorous activity. Consistent with this, those on wheels (e.g. bicycles, roller blades, strollers) used masks less often than those not on wheels. No differences in mask use were seen based on group size, weekdays vs. weekend days, percentage poverty level of the neighborhood setting being observed, or whether people kept at least a 6-foot distance from others. Neighborhood population density, however, was positively associated with higher correct mask use. Those observed on commercial streets were more likely to wear masks correctly compared to those in parks or playgrounds. Our model confirmed mask adherence was significantly higher in October after the President’s infection was announced than in both August and September (adjusted odds ratio = 1.377, p = .0097).

Table 2

Model of mask use over time.

Variables	estimate	SD	95% C.I.		p-value
Intercept	-2.80	-0.77	-4.83	-0.77	0.007
Toddler	-2.21	-1.67	-2.76	-1.67	< .0001
Child	-0.64	-0.27	-1.01	-0.27	0.0007
Teen	-0.91	-0.54	-1.27	-0.54	< .0001
Adult	-0.40	0.11	-0.62	-0.18	0.0004
Senior	ref	--	--	--	--
Female	0.49	0.06	0.37	0.61	< .0001
Non-Binary/Unknown	-0.19	0.46	-1.10	0.72	0.69
Male	ref	--	--	--	--
Non-Hispanic Black/African American	-0.42	0.17	-0.74	-0.09	0.01
Non-Hispanic Asian	0.52	0.19	0.16	0.89	0.005
Hispanic/Latinx	-0.74	0.22	-1.18	-0.31	0.0009
Unknown/unable to determine	0.23	0.15	-0.07	0.53	0.13
Non-Hispanic White	ref	--	--	--	--
Sedentary	-0.19	0.26	-0.70	0.31	0.46
Moderate	0.83	0.22	0.40	1.26	0.0002
Vigorous	ref	--	--	--	--
Not in a group	0.84	0.99	-1.10	2.78	0.40
group of 2	0.88	0.95	-0.99	2.74	0.36
group of 3 to 5	0.92	0.99	-1.02	2.85	0.35
group of 6 to 9	0.31	1.01	-1.68	2.29	0.76
group of 10 or more	ref	--	--	--	--
Physically distanced	-0.06	0.10	-0.26	0.14	0.55
Not physically distanced	ref	--	--	--	--
On wheels	-0.78	0.23	-1.23	-0.33	0.0007
Not on wheels	ref	--	--	--	--
Weekend	-0.17	0.12	-0.40	0.06	0.14
Weekday	ref	--	--	--	--
% households below poverty	0.003	0.01	-0.02	0.02	0.79
Commercial Street	1.05	0.27	0.52	1.58	0.0001
Neighborhood Park	0.81	0.29	0.25	1.38	0.0050
Playground	ref	--	--	--	--
Population density	0.05	0.02	0.01	0.09	0.0250
Prior to October 2, 2020	0.11	0.11	-0.10	0.32	0.3057
On or after Oct 2, 2020	0.35	0.14	0.09	0.62	0.0097
August, 2020	ref	--	--	--	--

Discussion

The City of Philadelphia Health Dept engaged in extraordinary efforts to promote mask use throughout the summer and issued additional detailed instructions on appropriate wear on September 15, 2020. In spite of these efforts, increased correct mask use was not seen until after the President’s infection was announced on October 2, 2020.

Although this is a serial cross-sectional observational study and the same people were not observed on each occasion, the increase in correct mask wearing appears to be among those who already had masks, because there was virtually no change in the proportion of those without a mask. It’s possible that the news may have instilled increased fear of the disease, resulting in those having masks being more careful in their appropriate use (e.g., both nose and mouth covered) in public settings. The rise in correct mask use after the President’s COVID-19 infection suggests that the behavior of our leaders has a significant impact on population adherence to public health guidelines.

Although the City of Philadelphia did issue guidance about mask adherence, it is likely that this did not receive as much attention as the President’s infections which made headlines in the national news for many days. It’s possible that the prominence of the news was an even more likely trigger for increased adherence.

Considering the contagiousness and virulence of COVID-19, the continued lack of mask use among 36% of those observed is concerning. Although outdoor settings are considered lower risk than indoor settings, the spaces observed were all public outdoor areas where people could come into contact with others and be exposed to aerosolized droplets. Even though outdoor settings provide better ventilation when one is not distanced or protected by masks, an increasing amount of time spent in close proximity to others also increases the risk of transmission, even in an outdoor setting [15].

Because the risk of transmission is a function of both dosage and duration of exposure, settings where people spend time, like in parks or playgrounds are places where masks should be worn. Yet people were less likely to wear them in parks than on commercial streets, possibly because they may have more control over distancing in these settings.

Meanwhile, important and yet unanswered questions include whether mask wearing in one setting is a good proxy for mask adherence in other areas and whether mask adherence in outdoor settings is its own predictor of transmission risk. Further, it is important to determine whether seeing others without masks establishes a norm or signals that mask adherence is unimportant, factors that could potentially undermine COVID-19 control efforts.

The study has several limitations. All the data are based on observations and estimates from trained field staff. Although the methods have high reliability, there may have been some misclassifications. In outdoor settings the risk for transmission of COVID-19 is lower than indoors, so mask adherence in these settings may not predict transmission. We could not know the relationship of people who were not wearing masks and were not distanced from each other. It is possible they lived in the same household and thus the guidelines were not applicable to their situation. This is also an observational study, not a randomized controlled trial, so causal inferences are speculative.

Our sample size was based on prior studies using direct observations, where anywhere between 6 to 50 sites (e.g., neighborhood parks, recreation centers), have been selected for direct observations. Each observation hour was expected to allow documentation of at least 60 individuals. We expected that we would need to observe at least 1000 individuals, and this did turn out to be sufficient. The number of locations and sample size was also influenced by the limited manpower available.

Although we observed increased adherence after President Trump was infected and not after the City Health Dept issued additional mask adherence guidance, we can only hypothesize that the prominence of the news and the real-life example showing how non-adherence leads to infection is what inspired this change. Certainly, publicity and widespread dissemination of information and guidance has been shown to be a critical predictor of behavior change in many other public health interventions [16-19]. Personalizing information is also an effective advertising technique as influencers and testimonials are known to be powerful methods for promoting behavior change [20].

There are multiple implications of our findings. The relatively low adherence rates in commercial settings provided a strong rationale for the Dept. of Public Health to act, which they did. However, their resources did not match the avalanche of publicity that accompanied the news of President Trump’s infection. This suggests that local public health agencies need more resources for information campaigns and enforcement activities. Given the multiple sources of misinformation about the pandemic, directing resources to disseminate clear and factual information about prevention is sorely needed. Given that the percentage of persons with no masks remained consistently high even after the President became infected, suggests that even widely disseminated information campaigns may be insufficient to obtain compliance.

The need for mask wearing is likely to continue, not only due to variants of COVID-19, like Delta, but also due to the potential emergence of other viruses, given our recent experience with H1NI and MERS just in the past few decades [21,22]. Additional consideration should be made for increasing monitoring and possibly stronger enforcement efforts in higher risk public settings where people may spend an extended time in close proximity to others.

7 Jul 2021

PONE-D-20-38624

Increased Mask Adherence after President Trump Infected with COVID-19

PLOS ONE

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Reviewer #1: The article presents a relevant and innovative theme. Some small adjustments must be made, they are:

- Improve the introduction, putting an international panorama on the theme (how is the relation of the use of masks in other countries)?

- Improve at the end of the discussion, what are the limitations of the study.

- Create a paragraph at the end of the discussion with the practical / clinical implications of your study.

- Improve completion by detailing in a topic.

Reviewer #2: I am pleased to share my comment, for the article entitled: Increased Mask Adherence after President Trump Infected with COVID-19

Use the word leader or politicians instead of the names of people in the title.

The necessity and importance of the study is not properly explained.

Why Philadelphia was studied

What is the importance of the study results?

Who will benefit from the research results?

In the introduction, use more studies and explain the importance of study.

The method part should be described step by step and in more detail.

How was the correct use of the mask by people examined?

Did people know they were being watched by the research team?

People are constantly moving and reorienting, how did you measure the appropriate social distance?

30 locations, why only parks, playgrounds and shopping streets? Are restaurants, passages (shopping malls) and entertainment centers less important?

How can you verify the accuracy of your observations?

How many days were the survey days? How many hours were observed each day?

Were the weather conditions different between the review days and the days before?

Mention study limitations?

Conclusions should be based on the findings of the study.

What are the benefits of the study for the health system?

In the discussion section: in addition to describing the study and its important findings, Compare the findings with other studies and describe the solutions and challenges in this context

Reviewer #3: Title: appropriate

Abstract: appropriate and adequate

Introduction: Authors have indicated the justification to do the study.

Methodology: It was not stated the number of adequate sample size for this research. The justification in choosing the location to be observed was not clearly expelled in the methodology. The characteristics of observers in the study were not clearly stated and various background may promotes bias that may affect the findings of the study. It must be addressed as limitation if there is.

The SOMAD protocol showing that authors made attempt in standardising the research tool and data collection.

Results: appropriate

Discussion: the limitation of the study ie potential bias, limitation on generalisation of the findings were not discussed.

**********

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Reviewer #1: Yes: Mateus A.

Reviewer #2: No

Reviewer #3: No

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17 Nov 2021

We revised the cover letter to include the funding statement.

(RAND is not a commercial company but a non-profit research institute.)

Reviewer #1: The article presents a relevant and innovative theme. Some small adjustments must be made, they are:

- Improve the introduction, putting an international panorama on the theme (how is the relation of the use of masks in other countries)?

We added Brazil as a country where mask adherence has been politicized.

- Improve at the end of the discussion, what are the limitations of the study.

We added additional limitations.

- Create a paragraph at the end of the discussion with the practical / clinical implications of your study.

We added this.

- Improve completion by detailing in a topic. Not sure what this means, but hope we provided sufficient detail.

Reviewer #2: I am pleased to share my comment, for the article entitled: Increased Mask Adherence after President Trump Infected with COVID-19

Use the word leader or politicians instead of the names of people in the title.

We changed to world leader.

The necessity and importance of the study is not properly explained.

The importance is due to prevention of spread of a deadly virus. Mask adherence is critical. Countries that have higher adherence have lower case rates.

Why Philadelphia was studied.

This was a matter of convenience, it is where our staff was located. We had instituted surveillance prior to President Trumps Covid-19 infection.

What is the importance of the study results?

The findings demonstrate the importance of messaging and media. People paid more attention when President Trump was infected than to health department warnings. Possibly giving examples and making the consequences more real maybe more effective.

Who will benefit from the research results?

Leaders, public health professionals and health care providers who want to increase adherence to public health guidance.

In the introduction, use more studies and explain the importance of study.

We added information on the importance of our study, but there are no similar studies that have used direct observation to monitor mask adherence.

The method part should be described step by step and in more detail.

We expanded.

How was the correct use of the mask by people examined?

By observation. Correct use was defined as covering both mouth and nose.

Did people know they were being watched by the research team? This is unknown. We had no interaction with those being observed.

People are constantly moving and reorienting, how did you measure the appropriate social distance?

This was a visual estimate.

30 locations, why only parks, playgrounds and shopping streets? Are restaurants, passages (shopping malls) and entertainment centers less important?

We stuck to outdoor locations for safety of the data collectors.

How can you verify the accuracy of your observations?

We conducted reliability testing. The results have been published and these are now referenced.

How many days were the survey days? How many hours were observed each day?

Each site was observed for one hour on the day and time of day over time.

Were the weather conditions different between the review days and the days before?

Yes, weather follows the seasons and the summer is typically warmer than the fall.

Mention study limitations? We added some more limitations.

Conclusions should be based on the findings of the study. We agree

What are the benefits of the study for the health system?

We added a paragraph on the implications.

In the discussion section: in addition to describing the study and its important findings, Compare the findings with other studies and describe the solutions and challenges in this context.

We are not aware of other published studies that have conducted serial observations of mask adherence. Nevertheless, there are multiple other studies employing direct observation that successfully document behavioral trends.

Reviewer #3: Title: appropriate

Abstract: appropriate and adequate

Introduction: Authors have indicated the justification to do the study.

Methodology: It was not stated the number of adequate sample size for this research. The justification in choosing the location to be observed was not clearly expelled in the methodology. The characteristics of observers in the study were not clearly stated and various background may promotes bias that may affect the findings of the study. It must be addressed as limitation if there is.

Because this is an innovative study there were no prior data informing sample size calculations. Our sample size was based on three considerations. First, the number of observation locations was similar to our previous studies of direct observations of human physical activity behavior in built environment. In many of our past studies, we usually selected anywhere between 6 to 50 sites (e.g., neighborhood parks, recreation centers), in a city for direct observations. Second, the number of observed subjects needs to be sufficient to draw inference for the outcome of interest. Since our outcome is a binary random variable in this paper, a total of 1000 or more subjects yielded sufficient power under the regular power setting of 2-sided p<.05 and power>.8 and for a small to medium effect size. As shown in Table 2, in retrospect we did have sufficient statistical power to declare significance for many substantive predictors. Third, the sample size was also constrained by the available manpower we could deploy during the critical study period. We were not able to further increase the number of locations given the available and trained observers.

We added this to the limitations.

The SOMAD protocol showing that authors made attempt in standardising the research tool and data collection.

Results: appropriate

Discussion: the limitation of the study ie potential bias, limitation on generalisation of the findings were not discussed.

We expanded the discussion of limitations.

Submitted filename: response to reviewers.docx

Click here for additional data file.

22 Nov 2021

PONE-D-20-38624R1Increased Mask Adherence after World Leader Infected with COVID-19PLOS ONE

Dear Dr. Cohen,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

==============================

The reviewer has suggested minor revision. Kindly address the comments

==============================

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We look forward to receiving your revised manuscript.

Kind regards,

Kingston Rajiah

Academic Editor

PLOS ONE

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Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #2: I Don't Know

**********

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The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #2: Yes

**********

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Reviewer #2: Yes

**********

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Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #2: The title of the study will become more general by changing the form below:

Increased Mask Adherence after Important politicians Infected with COVID-19

Other corrections appear to have been made.

**********

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Reviewer #2: No

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26 Nov 2021

I changed the title as suggested.

Submitted filename: Response to reviewersPO.docx

Click here for additional data file.

2 Dec 2021

Increased Mask Adherence after Important Pollitician Infected with COVID-19

PONE-D-20-38624R2

Dear Dr. Cohen,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Kingston Rajiah

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

20 Dec 2021

PONE-D-20-38624R2

Increased Mask Adherence after Important Politician Infected with COVID-19

Dear Dr. Cohen:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

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Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Kingston Rajiah

Academic Editor

PLOS ONE