Prevalence of SARS-CoV-2 infection in Baja California, Mexico: Findings from a community-based survey in February 2021 in the Mexico-United States border

Between March 2020 and February 2021, the state of Baja California, Mexico, which borders the United States, registered 46,118 confirmed cases of COVID-19 with a mortality rate of 238.2 deaths per 100,000 residents. Given limited access to testing, the population prevalence of SARS-CoV-2 infection is unknown. The objective of this study is to estimate the seroprevalence and real time polymerase chain reaction (RT-PCR) prevalence of SARS-CoV-2 infection in the three most populous cities of Baja California prior to scale-up of a national COVID-19 vaccination campaign. Probabilistic three-stage clustered sampling was used to conduct a population-based household survey of residents five years and older in the three cities. RT-PCR testing was performed on nasopharyngeal swabs and SARS-CoV-2 seropositivity was determined by IgG antibody testing using fingerstick blood samples. An interviewer-administered questionnaire assessed participants' knowledge, attitudes, and preventive practices regarding COVID-19. In total, 1,126 individuals (unweighted sample) were surveyed across the three cities. Overall prevalence of SARS-CoV-2 infection by RT-PCR was 7.8% (95% CI 5.5–11.0) and IgG seroprevalence was 21.1% (95% CI 17.4–25.2). There was no association between border crossing in the past 6 months and SARS-CoV-2 prevalence (unadjusted OR 0.40, 95%CI 0.12–1.30). While face mask use and frequent hand washing were common among participants, quarantine or social isolation at home to prevent infection was not. Regarding vaccination willingness, 30.4% (95% CI 24.4–3 7.1) of participants said they were very unlikely to get vaccinated. Given the high prevalence of active SARS-CoV-2 infection in Baja California at the end of the first year of the pandemic, combined with its low seroprevalence and the considerable proportion of vaccine hesitancy, this important area along the Mexico-United States border faces major challenges in terms of health literacy and vaccine uptake, which need to be further explored, along with its implications for border restrictions in future epidemics.

"It's hard for everyone" systemic barriers to home confinement to prevent community spread of COVID-19.

Rapid identification and isolation/quarantine of COVID-19 cases or close contacts, respectively, is a vital tool to support safe, in-person learning. However, safe isolation or quarantine for a young child also necessitates home confinement for at least one adult caregiver, as well as rapid learning material development by the teacher to minimize learning loss. The purpose of this study is to better understand barriers and supports to student home confinement. We conducted a mixed-methods study using focus group discussions and a self-administered online survey with parents and staff members from 12 elementary schools and childcare sites across San Diego County serving low-income and socially vulnerable families. Focus group participants reported that mental distress and loneliness, learning loss, childcare, food, income loss, and overcrowded housing were major barriers related to home confinement. The experiences described by FGD participants were prevalent in a concurrent community survey: 25% of participants reported that isolation would be extremely difficult for a household member who tested positive or was exposed to COVID-19, and 20% were extremely concerned about learning loss while in isolation or quarantine. Our findings suggest that there are serious structural impediments to safely completing the entire recommended course of isolation or quarantine, and that the potential for isolation or quarantine may also lead to increased hesitancy to access diagnostic testing.

BACKGROUND: During the COVID-19 pandemic, home confinement (isolation and quarantine) are important public health tools to keep children learning in-person at schools. However, isolation or quarantine for young children also means that often their caregivers must also go into home confinement, as well as forcing teachers to adapt their lessons to online teaching. PURPOSE: The purpose of this study is to better understand what makes home confinement comfortable or difficult for students and their families. METHODS: We did focus group discussions and shared an online survey with parents and staff members from 12 elementary schools and childcare centers across San Diego County vulnerable families. RESULTS: Focus group participants said that mental distress and loneliness, learning loss, childcare, food, income loss, and overcrowded housing made home confinement hard to do. Also 25% of survey participants said that isolation would be difficult for a household member who tested positive or was exposed to COVID-19, and 20% were really concerned about their child's learning loss if the family had to isolate or do quarantine. CONCLUSIONS: Our study's results suggest that there are serious structural issues for school families to safely go into isolation or quarantine, and because of this may make families more hesitant to get tested for COVID-19.

Challenges of COVID-19 Case Investigation and Contact Tracing in School Settings: An Initial Investigation.

BACKGROUND: Case investigation and contact tracing (CI/CT) are important public health tools to interrupt COVID-19 transmission. Our study aims to understand how parents and school staff perceive COVID-19 CI/CT. METHODS: Using a mixed methods approach, we distributed a community survey and conducted 15 focus group discussions (FGDs) in English and Spanish between December 2020 and March 2021 with 20 parents and 22 staff from schools in San Diego County ZIP Codes with COVID-19 rates in the top quintile as of August 2020. RESULTS: One in 4 survey respondents reported that they would be reluctant to participate in CI/CT. FGDs revealed themes of mistrust in government authorities, overburdened institutions, unfamiliarity with CI/CT, and uncertainty about its reliability. School community members emphasized that parents trust schools to be involved in CI/CT efforts, but schools are overwhelmed with this added responsibility. CONCLUSIONS: Investing in schools as community hubs is necessary so they can become important partners in prevention and mitigation in public health.

Safer at school early alert: an observational study of wastewater and surface monitoring to detect COVID-19 in elementary schools.

Background: Schools are high-risk settings for SARS-CoV-2 transmission, but necessary for children's educational and social-emotional wellbeing. Previous research suggests that wastewater monitoring can detect SARS-CoV-2 infections in controlled residential settings with high levels of accuracy. However, its effective accuracy, cost, and feasibility in non-residential community settings is unknown. Methods: The objective of this study was to determine the effectiveness and accuracy of community-based passive wastewater and surface (environmental) surveillance to detect SARS-CoV-2 infection in neighborhood schools compared to weekly diagnostic (PCR) testing. We implemented an environmental surveillance system in nine elementary schools with 1700 regularly present staff and students in southern California. The system was validated from November 2020 to March 2021. Findings: In 447 data collection days across the nine sites 89 individuals tested positive for COVID-19, and SARS-CoV-2 was detected in 374 surface samples and 133 wastewater samples. Ninety-three percent of identified cases were associated with an environmental sample (95% CI: 88%-98%); 67% were associated with a positive wastewater sample (95% CI: 57%-77%), and 40% were associated with a positive surface sample (95% CI: 29%-52%). The techniques we utilized allowed for near-complete genomic sequencing of wastewater and surface samples. Interpretation: Passive environmental surveillance can detect the presence of COVID-19 cases in non-residential community school settings with a high degree of accuracy. Funding: County of San Diego, Health and Human Services Agency, National Institutes of Health, National Science Foundation, Centers for Disease Control.

COVID-19 disproportionately impacts access to basic needs among households with disabled members.

BACKGROUND: The COVID-19 pandemic has disproportionately impacted disabled people, especially those who are members of marginalized communities that were already denied access to the resources and opportunities necessary to ensure health equity before the pandemic. OBJECTIVE: Compare COVID-19 impact on basic needs access among households with and without disabled adults. METHODS: An online survey was distributed to households with children enrolled in one of 30 socially vulnerable elementary or middle schools in San Diego County, California. We measured disability using the single-item Global Activities Limitations Indicator. We measured pandemic impacts on basic needs access using the RADx-UP common data elements toolkit. We then assessed number of impact items reported by household disability using multivariable linear regression, adjusting for household income, household size, education, parent gender, and child's ethnicity. RESULTS: Of 304 participants, 41% had at least one disabled household member. Participants reporting a disabled household member were more likely to report challenges accessing basic needs, such as food, housing, healthcare, transportation, medication, and stable income during the pandemic (all p < 0.05). Difficulty accessing basic needs was significantly associated with household income and parent gender in the final regression model. CONCLUSIONS: Households with a disabled member were significantly more likely to experience difficulty accessing basic needs during the COVID-19 pandemic. This has important implications for the disproportionate impact of COVID-19 on disabled people, especially those from low-income communities that already face barriers to accessing resources. To improve COVID-19 outcomes for disabled people, we must focus on meeting their basic needs.

Prevalence of SARS-CoV-2 infection in Baja California, Mexico: Findings from a community-based survey in February 2021 in the Mexico-United States border.

Between March 2020 and February 2021, the state of Baja California, Mexico, which borders the United States, registered 46,118 confirmed cases of COVID-19 with a mortality rate of 238.2 deaths per 100,000 residents. Given limited access to testing, the population prevalence of SARS-CoV-2 infection is unknown. The objective of this study is to estimate the seroprevalence and real time polymerase chain reaction (RT-PCR) prevalence of SARS-CoV-2 infection in the three most populous cities of Baja California prior to scale-up of a national COVID-19 vaccination campaign. Probabilistic three-stage clustered sampling was used to conduct a population-based household survey of residents five years and older in the three cities. RT-PCR testing was performed on nasopharyngeal swabs and SARS-CoV-2 seropositivity was determined by IgG antibody testing using fingerstick blood samples. An interviewer-administered questionnaire assessed participants' knowledge, attitudes, and preventive practices regarding COVID-19. In total, 1,126 individuals (unweighted sample) were surveyed across the three cities. Overall prevalence of SARS-CoV-2 infection by RT-PCR was 7.8% (95% CI 5.5-11.0) and IgG seroprevalence was 21.1% (95% CI 17.4-25.2). There was no association between border crossing in the past 6 months and SARS-CoV-2 prevalence (unadjusted OR 0.40, 95%CI 0.12-1.30). While face mask use and frequent hand washing were common among participants, quarantine or social isolation at home to prevent infection was not. Regarding vaccination willingness, 30.4% (95% CI 24.4-3 7.1) of participants said they were very unlikely to get vaccinated. Given the high prevalence of active SARS-CoV-2 infection in Baja California at the end of the first year of the pandemic, combined with its low seroprevalence and the considerable proportion of vaccine hesitancy, this important area along the Mexico-United States border faces major challenges in terms of health literacy and vaccine uptake, which need to be further explored, along with its implications for border restrictions in future epidemics.

Impact of COVID-19 on tuberculosis detection and treatment in Baja California, México.

In 2020, Mexico reported the lowest tuberculosis (TB) incidence on record, and it is unclear to what extent COVID-19 has impacted TB surveillance, diagnosis, and treatment. It is important to understand COVID-19's impact in Baja California (BC), which has the highest TB burden in Mexico. With the increasing number of migrants and asylum seekers arriving in BC, limited resources and crowded living conditions increase the risk of TB transmission. The purpose of this study was to assess the impact of COVID-19 on TB diagnosis and treatment in BC. We were also interested in health disparities experienced by migrants in BC. We conducted a mixed methods analysis using quantitative surveillance data obtained from the Mexico National TB Program (NTP) and qualitative data collected through in-depth interviews and focus group discussions with TB program directors and personnel in BC's four provincial health jurisdictions. Compared to the year prior, surveillance data from March 2020 - February 2021 revealed that TB incidence in BC declined by 30.9% and favorable TB outcomes (TB cure or treatment completion) declined by 49.8%. Elucidating differences by migrant status was complicated by the lack of standardized collection of migrant status by the NTP. Qualitative analysis revealed that TB diagnostic and treatment supplies and services became limited and disproportionately accessible across jurisdictions since the pandemic began; however, favorable adaptations were also reported, such as increased telemedicine use and streamlined care referral processes. Participants shared that migrant status is susceptible to misclassification and that TB care is difficult due to the transitory nature of migrants. This study did not identify major differences in TB service delivery or access between migrants and non-migrants in BC; however, migrant status was frequently missing. COVID-19 has overwhelmed health systems worldwide, disrupting timely TB diagnostic and treatment services, and potentially caused underdiagnosis of TB in BC. TB programs in BC should quickly restore essential services that were disrupted by COVID-19 while identifying and preserving beneficial program adaptations, such as telemedicine and streamlined care referral processes. Improved methods for documenting migrant status of TB cases are also needed.

The impact of the COVID-19 pandemic among migrants in shelters in Tijuana, Baja California, Mexico.

INTRODUCTION: Migrants, especially those in temporary accommodations like camps and shelters, might be a vulnerable population during the COVID-19 pandemic, but little is known about the impact of the pandemic in these settings in low-income and middle-income countries. We assessed SARS-CoV-2 seropositivity and RNA prevalence, the correlates of seropositivity (emphasising socially determined conditions), and the socioeconomic impacts of the pandemic among migrants living in shelters in Tijuana, a city on the Mexico-US border. METHODS: We conducted a cross-sectional, non-probability survey of migrants living in shelters in Tijuana in November-December 2020 and February-April 2021. Participants completed a questionnaire and provided anterior nasal swab and blood samples for detection of SARS-CoV-2 RNA and antibodies (IgG and IgM), respectively. We explored whether SARS-CoV-2 infection was associated with sociodemographic and migration-related variables, access to sanitation, protective behaviours and health-related factors. RESULTS: Overall, 481 participants were enrolled, 67.7% from Northern Central America, 55.3% women, mean age 33.2 years. Seven (1.5%) participants had nasal swabs positive for SARS-CoV-2 RNA and 53.0% were SARS-CoV-2 seropositive. Avoiding public transportation (OR 0.59, 95% CI 0.39 to 0.90) and months living in Tijuana (OR 1.06, 95% CI 1.02 to 1.10) were associated with seropositivity. Sleeping on the streets or other risky places and having diabetes were marginally associated with seropositivity. Most participants (90.2%) had experienced some socioeconomic impact of the pandemic (eg, diminished income, job loss). CONCLUSION: Compared with results from other studies conducted in the general population in Mexico at a similar time, migrants living in shelters were at increased risk of acquiring SARS-CoV-2, and they suffered considerable adverse socioeconomic impacts as a consequence of the pandemic. Expanded public health and other social support systems are needed to protect migrants from COVID-19 and reduce health inequities.