Tick bite risk factors and prevention measures in an area with emerging Powassan virus disease.

Background: In the United States (U.S.), Powassan virus is primarily transmitted to humans by the black-legged tick (Ixodes scapularis). Rarely, infections can present as severe neuroinvasive disease. In 2019, four neuroinvasive disease cases were reported in Sussex County, New Jersey, U.S. We administered a survey to county residents to better understand tick bite risk factors and the performance of personal prevention measures. Methods: A survey was administered in October 2019 to adult residents of randomly selected households. Questions focused on tick bite prevention and risk factors. Crude and adjusted odds ratios (ORs) and 95% confidence intervals were calculated for various outcomes. Results: Of 274 participants, 25% were previously diagnosed with a tick-borne disease, and 42% reported finding an attached tick in 2019. Yardwork and gardening (OR = 7.38) and spending >50 hours outdoors per week (OR = 8.15) were associated with finding an attached tick. Finding an attached tick was inversely associated with the number of prevention measures used, indicating that a layered approach could reduce the risk of tick bites. Those who performed post-outdoor activity prevention measures (e.g., tick checks) were less likely to have a tick attached compared to finding a crawling tick. Conclusion: Compliance with prevention recommendations was low, despite a high prevalence of reported tick bites and significant outdoor exposures. Older adults and persons who spend significant time outdoors or engage in yardwork or gardening were at the highest risk of tick bites. Additional research is needed to further understand the barriers to tick bite prevention.

Household characteristics associated with surface contamination of SARS-CoV-2 and frequency of RT-PCR and viral culture positivity-California and Colorado, 2021.

While risk of fomite transmission of SARS-CoV-2 is considered low, there is limited environmental data within households. This January-April 2021 investigation describes frequency and types of surfaces positive for SARS-CoV-2 by real-time reverse transcription polymerase chain reaction (RT-PCR) among residences with ≥1 SARS-CoV-2 infection, and associations of household characteristics with surface RT-PCR and viable virus positivity. Of 1232 samples from 124 households, 27.8% (n = 342) were RT-PCR positive with nightstands (44.1%) and pillows (40.9%) most frequently positive. SARS-CoV-2 lineage, documented household transmission, greater number of infected persons, shorter interval between illness onset and sampling, total household symptoms, proportion of infected persons ≤12 years old, and persons exhibiting upper respiratory symptoms or diarrhea were associated with more positive surfaces. Viable virus was isolated from 0.2% (n = 3 samples from one household) of all samples. This investigation suggests that while SARS-CoV-2 on surfaces is common, fomite transmission risk in households is low.

SARS-CoV-2 infection risk among vaccinated and unvaccinated household members during the Alpha variant surge - Denver, Colorado, and San Diego, California, January-April 2021.

BACKGROUND: COVID-19 vaccination reduces SARS-CoV-2 infection and transmission. However, evidence is emerging on the degree of protection across variants and in high-transmission settings. To better understand the protection afforded by vaccination specifically in a high-transmission setting, we examined household transmission of SARS-CoV-2 during a period of high community incidence with predominant SARS-CoV-2 B.1.1.7 (Alpha) variant, among vaccinated and unvaccinated contacts. METHODS: We conducted a household transmission investigation in San Diego County, California, and Denver, Colorado, during January-April 2021. Households were enrolled if they had at least one person with documented SARS-CoV-2 infection. We collected nasopharyngeal swabs, blood, demographic information, and vaccination history from all consenting household members. We compared infection risks (IRs), RT-PCR cycle threshold values, SARS-CoV-2 culture results, and antibody statuses among vaccinated and unvaccinated household contacts. RESULTS: We enrolled 493 individuals from 138 households. The SARS-CoV-2 variant was identified from 121/138 households (88%). The most common variants were Alpha (75/121, 62%) and Epsilon (19/121, 16%). There were no households with discordant lineages among household members. One fully vaccinated secondary case was symptomatic (13%); the other 5 were asymptomatic (87%). Among unvaccinated secondary cases, 105/108 (97%) were symptomatic. Among 127 households with a single primary case, the IR for household contacts was 45% (146/322; 95% Confidence Interval [CI] 40-51%). The observed IR was higher in unvaccinated (130/257, 49%, 95% CI 45-57%) than fully vaccinated contacts (6/26, 23%, 95% CI 11-42%). A lower proportion of households with a fully vaccinated primary case had secondary cases (1/5, 20%) than households with an unvaccinated primary case (66/108, 62%). CONCLUSIONS: Although SARS-CoV-2 infections in vaccinated household contacts were reported in this high transmission setting, full vaccination protected against SARS-CoV-2 infection. These findings further support the protective effect of COVID-19 vaccination and highlight the need for ongoing vaccination among eligible persons.

Seroprevalence of Powassan Virus Infection in an Area Experiencing a Cluster of Disease Cases: Sussex County, New Jersey, 2019.

In 2019, a geographically focal cluster of 3 Powassan virus neuroinvasive disease cases occurred in New Jersey. We conducted a serosurvey of 273 adult area residents and estimated that immunoglobulin M seroprevalence was 0.31% (95% confidence interval [CI], .04%-1.00%) and 23% (95% CI, 7%-100%) of infections result in neuroinvasive disease.

Behaviors Associated With Household Transmission of SARS-CoV-2 in California and Colorado, January 2021-April 2021.

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.

Using the Vape Shop Standardized Tobacco Assessment for Retail Settings (V-STARS) to Assess Product Availability, Price Promotions, and Messaging in New Hampshire Vape Shop Retailers.

OBJECTIVES: This is the first statewide census of the product availability, price promotions, and product messaging of vape shops. METHODS: A comprehensive list of New Hampshire vape shops was developed through a previously validated online search method. Store audits were conducted in 55 stores between January and February 2016 using the Vape Shop Standardized Tobacco Assessment for Retail Settings (V-STARS). RESULTS: Modifiable devices and cig-alikes were sold in 92.6% and 14.6% of stores, respectively. Cross-product promotions with tobacco products were rare, and messaging promoting e-cigarettes as effective cessation devices was found in 27.3% of all stores. Candy/fruit and menthol e-liquids were most commonly found in stores, and sampling of products was available in 83.6% of stores. Ten (18.2%) stores did not have a minimum age sign posted, and self-service sampling displays were available in about one-fifth of stores. CONCLUSIONS: Using V-STARS to conduct retail assessments of vape shops is feasible and is important for assessing the changing retail environment of vape shops. Vape shops distinguish themselves from traditional tobacco product retailers and offer a variety of products to customize a consumer's experience. Regulations and effective enforcement ensuring accurate health messages is essential.