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BACKGROUND: In Spring 2021, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.7 (Alpha) became the predominant variant in the United States. Research suggests that Alpha has increased transmissibility compared with non-Alpha lineages. We estimated household secondary infection risk (SIR), assessed characteristics associated with transmission, and compared symptoms of persons with Alpha and non-Alpha infections. METHODS: We followed households with SARS-CoV-2 infection for 2 weeks in San Diego County and metropolitan Denver, January to April 2021. We collected epidemiologic information and biospecimens for serology, reverse transcription-polymerase chain reaction (RT-PCR), and whole-genome sequencing. We stratified SIR and symptoms by lineage and identified characteristics associated with transmission using generalized estimating equations. RESULTS: We investigated 127 households with 322 household contacts; 72 households (56.7%) had member(s) with secondary infections. SIRs were not significantly higher for Alpha (61.0% [95% confidence interval, 52.4-69.0%]) than non-Alpha (55.6% [44.7-65.9%], Pâ =â .49). In households with Alpha, persons who identified as Asian or Hispanic/Latino had significantly higher SIRs than those who identified as White (Pâ =â .01 and .03, respectively). Close contact (eg, kissing, hugging) with primary cases was associated with increased transmission for all lineages. Persons with Alpha infection were more likely to report constitutional symptoms than persons with non-Alpha (86.9% vs 76.8%, Pâ =â .05). CONCLUSIONS: Household SIRs were similar for Alpha and non-Alpha. Comparable SIRs may be due to saturation of transmission risk in households due to extensive close contact, or true lack of difference in transmission rates. Avoiding close contact within households may reduce SARS-CoV-2 transmission for all lineages among household members.
Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiology , Family Characteristics , Humans , SARS-CoV-2/genetics , United States/epidemiologyABSTRACT
OBJECTIVE: To assess the household secondary infection risk (SIR) of B.1.1.7 (Alpha) and non-Alpha lineages of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among children. STUDY DESIGN: During January to April 2021, we prospectively followed households with a SARS-CoV-2 infection. We collected questionnaires, serial nasopharyngeal swabs for reverse transcription polymerase chain reaction testing and whole genome sequencing, and serial blood samples for serology testing. We calculated SIRs by primary case age (pediatric vs adult), household contact age, and viral lineage. We evaluated risk factors associated with transmission and described symptom profiles among children. RESULTS: Among 36 households with pediatric primary cases, 21 (58%) had secondary infections. Among 91 households with adult primary cases, 51 (56%) had secondary infections. SIRs among pediatric and adult primary cases were 45% and 54%, respectively (OR, 0.79; 95% CI, 0.41-1.54). SIRs among pediatric primary cases with Alpha and non-Alpha lineage were 55% and 46%, respectively (OR, 1.52; 95% CI, 0.51-4.53). SIRs among pediatric and adult household contacts were 55% and 49%, respectively (OR, 1.01; 95% CI, 0.68-1.50). Among pediatric contacts, no significant differences in the odds of acquiring infection by demographic or household characteristics were observed. CONCLUSIONS: Household transmission of SARS-CoV-2 from children and adult primary cases to household members was frequent. The risk of secondary infection was similar among child and adult household contacts. Among children, household transmission of SARS-CoV-2 and the risk of secondary infection was not influenced by lineage. Continued mitigation strategies (eg, masking, physical distancing, vaccination) are needed to protect at-risk groups regardless of virus lineage circulating in communities.
Subject(s)
COVID-19 , SARS-CoV-2 , Adult , COVID-19/epidemiology , California , Child , Colorado/epidemiology , HumansABSTRACT
Background: COVID-19 has had a significant public health impact on both the United States and Mexico. Cross-border mobility between southern California and Mexico raises questions of transmission trends between these jurisdictions. The objective of this project was to describe binational cases amongst California US-Mexico border county COVID-19 cases and compare incidence trends to cross-border Mexico jurisdictions. Methods: Interview data from persons with confirmed SARS-CoV-2 infections in San Diego County, CA and Imperial County, CA from February to June 2020 were reviewed for binational cases; demographics and connection to COVID-19 outbreaks were assessed. Graphs of COVID-19 incidence in San Diego County and Imperial County were compared to incidence graphs in cross-border Mexico jurisdictions of Tijuana and Mexicali. Results: Persons with COVID-19 and a binational case were older, more likely to be Hispanic, and reside in a border ZIP code than those without. Binational cases were a small proportion and tracked with overall cases during the study period. Conclusions: Binational cases had different trends than non-binational cases of SARS-CoV-2 in San Diego and Imperial counties from February to June 2020. Findings could inform SARS-CoV-2 mitigation strategies specific to the US-Mexico land border, particularly recommendations regarding cross-border land travel.
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BACKGROUND: Approximately 20,000 people died from influenza in the US in the 2019-2020 season. The best way to prevent influenza is to receive the influenza vaccine. Persons who are foreign-born experience disparities in access to, and utilization of, preventative healthcare, including vaccination. METHODS: National Health Interview Survey data were analyzed to assess differences in influenza vaccination coverage during the 2012-2013 through 2017-2018 influenza seasons among adults by nativity, citizenship status of foreign-born persons, race/ethnicity, and language of the interview. RESULTS: Influenza vaccination coverage increased significantly during the study period for US-born adults but did not change significantly among foreign-born racial/ethnic groups except for increases among foreign-born Hispanic adults. Coverage for foreign-born adults, those who completed an interview in a non-English language, and non-US citizens, had lower vaccination coverage during most influenza seasons studied, compared with US-born, English-interviewed, and US-citizen adults, respectively. CONCLUSIONS: Strategies to improve influenza vaccination uptake must consider foreign-born adults as an underserved population in need of focused, culturally-tailored outreach. Achieving high influenza vaccination coverage among the foreign-born population will help reduce illness among the essential workforce, achieve national vaccination goals, and reduce racial and ethnic disparities in vaccination coverage in the US.
Subject(s)
Influenza Vaccines , Influenza, Human , Adult , Citizenship , Ethnicity , Humans , Influenza, Human/prevention & control , Seasons , United States , Vaccination , Vaccination CoverageABSTRACT
In February 2020, during the early days of the COVID-19 pandemic, 232 evacuees from Wuhan, China, were placed under federal 14-day quarantine upon arrival at a US military base in San Diego, California. We describe the monitoring of evacuees and responders for symptoms of COVID-19, case and contact investigations, infection control procedures, and lessons learned to inform future quarantine protocols for evacuated people from a hot spot resulting from a novel pathogen. Thirteen (5.6%) evacuees had COVID-19-compatible symptoms and 2 (0.9%) had laboratory-confirmed SARS-CoV-2. Two case investigations identified 43 contacts; 3 (7.0%) contacts had symptoms but tested negative for SARS-CoV-2 infection. Daily symptom and temperature screening of evacuees and enacted infection control procedures resulted in rapid case identification and isolation and no detected secondary transmission among evacuees or responders. Lessons learned highlight the challenges associated with public health response to a novel pathogen and the evolution of mitigation strategies as knowledge of the pathogen evolves.
Subject(s)
COVID-19 , Quarantine , United States/epidemiology , Humans , COVID-19/epidemiology , Military Facilities , Pandemics/prevention & control , SARS-CoV-2 , China/epidemiologyABSTRACT
Introduction: Mitigation behaviors are key to preventing SARS-CoV-2 transmission. We identified the behaviors associated with secondary transmission from confirmed SARS-CoV-2 primary cases to household contacts and described the characteristics associated with reporting these behaviors. Methods: Households with confirmed SARS-CoV-2 infections were recruited in California and Colorado from January to April 2021. Self-reported behaviors and demographics were collected through interviews. We investigated behaviors associated with transmission and individual and household characteristics associated with behaviors using univariable and multivariable logistic regression with generalized estimating equations to account for household clustering. Results: Among household contacts of primary cases, 43.3% (133 of 307) became infected with SARS-CoV-2. When an adjusted analysis was conducted, household contacts who slept in the same bedroom with the primary case (AOR=2.19; 95% CI=1.25, 3.84) and ate food prepared by the primary case (AOR=1.98; 95% CI=1.02, 3.87) had increased odds of SARS-CoV-2 infection. Household contacts in homes ≤2,000 square feet had increased odds of sleeping in the same bedroom as the primary case compared with those in homes >2,000 square feet (AOR=3.97; 95% CI=1.73, 9.10). Parents, siblings, and other relationships (extended family, friends, or roommates) of the primary case had decreased odds of eating food prepared by the primary case compared with partners. Conclusions: Sleeping in the same bedroom as the primary case and eating food prepared by the primary case were associated with secondary transmission. Household dimension and relationship to the primary case were associated with these behaviors. Our findings encourage innovative means to promote adherence to mitigation measures that reduce household transmission.
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Importance: As self-collected home antigen tests become widely available, a better understanding of their performance during the course of SARS-CoV-2 infection is needed. Objective: To evaluate the diagnostic performance of home antigen tests compared with reverse transcription-polymerase chain reaction (RT-PCR) and viral culture by days from illness onset, as well as user acceptability. Design, Setting, and Participants: This prospective cohort study was conducted from January to May 2021 in San Diego County, California, and metropolitan Denver, Colorado. The convenience sample included adults and children with RT-PCR-confirmed infection who used self-collected home antigen tests for 15 days and underwent at least 1 nasopharyngeal swab for RT-PCR, viral culture, and sequencing. Exposures: SARS-CoV-2 infection. Main Outcomes and Measures: The primary outcome was the daily sensitivity of home antigen tests to detect RT-PCR-confirmed cases. Secondary outcomes included the daily percentage of antigen test, RT-PCR, and viral culture results that were positive, and antigen test sensitivity compared with same-day RT-PCR and cultures. Antigen test use errors and acceptability were assessed for a subset of participants. Results: This study enrolled 225 persons with RT-PCR-confirmed infection (median [range] age, 29 [1-83] years; 117 female participants [52%]; 10 [4%] Asian, 6 [3%] Black or African American, 50 [22%] Hispanic or Latino, 3 [1%] Native Hawaiian or Other Pacific Islander, 145 [64%] White, and 11 [5%] multiracial individuals) who completed 3044 antigen tests and 642 nasopharyngeal swabs. Antigen test sensitivity was 50% (95% CI, 45%-55%) during the infectious period, 64% (95% CI, 56%-70%) compared with same-day RT-PCR, and 84% (95% CI, 75%-90%) compared with same-day cultures. Antigen test sensitivity peaked 4 days after illness onset at 77% (95% CI, 69%-83%). Antigen test sensitivity improved with a second antigen test 1 to 2 days later, particularly early in the infection. Six days after illness onset, antigen test result positivity was 61% (95% CI, 53%-68%). Almost all (216 [96%]) surveyed individuals reported that they would be more likely to get tested for SARS-CoV-2 infection if home antigen tests were available over the counter. Conclusions and Relevance: The results of this cohort study of home antigen tests suggest that sensitivity for SARS-CoV-2 was moderate compared with RT-PCR and high compared with viral culture. The results also suggest that symptomatic individuals with an initial negative home antigen test result for SARS-CoV-2 infection should test again 1 to 2 days later because test sensitivity peaked several days after illness onset and improved with repeated testing.
Subject(s)
COVID-19 , Adult , COVID-19/diagnosis , Child , Cohort Studies , Female , Humans , Prospective Studies , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2/genetics , Sensitivity and SpecificityABSTRACT
BACKGROUND: Achieving health literacy is a critical step to improving health outcomes and the health of a nation. However, there is a lack of research on health literacy in low-resource countries, where maternal health outcomes are at their worst. OBJECTIVES: To examine the usefulness and feasibility of providing focused antenatal care (FANC) in a group setting using picture cards to improve patient-provider communication, patient engagement, and improve health literacy. DESIGN: An exploratory, mixed methods design was employed to gather pilot data using the Health Literacy Skills Framework. SETTINGS: A busy urban district hospital in the Ashanti Region of Ghana was used to gather data during 2014. PARTICIPANTS: A facility-driven convenience sample of midwives (n=6) aged 18 years or older, who could speak English or Twi, and had provided antenatal care at the participating hospital during the previous year prior to the start of the study participated in the study. METHODS: Data were collected using pre-test and post-test surveys, completed three months after the group FANC was implemented. A semi-structured focus group was conducted with four of the participating midwives and the registered nurse providing support and supervision for the study (n=5) at the time of the post-test. Data were analyzed concurrently to gain a broad understanding of patient communication, engagement, and group FANC. RESULTS: There were no significant differences in the mean communication (t(df=3)=0.541, p=0.626) and engagement (t(df=3)=-0.775, p=0.495) scores between the pre- and post-test. However, the focus group revealed the following themes: (a) improved communication through the use of picture cards; (b) enhanced information sharing and peer support through the facilitated group process and; and (c) an improved understanding of patient concerns. CONCLUSIONS: The improved communication noted through the use of picture cards and the enhanced information sharing and peer support elicited through the group FANC undoubtedly provided patients with additional tools to invoke self-determination, and carry out the behaviors they thought were most important to improve pregnancy outcomes.