Serological survey to estimate SARS-CoV-2 infection and antibody seroprevalence at a large public university: A cross-sectional study.

OBJECTIVE: This study investigated the seroprevalence of SARS-CoV-2 antibodies among adults over 18 years. DESIGN: Prospective cohort study. SETTINGS: A large public university. PARTICIPANTS: This study took volunteers over 5 days and recruited 1064 adult participants. PRIMARY OUTCOME MEASURES: Seroprevalence of SARS-CoV-2-specific antibodies due to previous exposure to SARS-CoV-2 and/or vaccination. RESULTS: The seroprevalence of the antireceptor binding domain (RBD) antibody was 90% by a lateral flow assay and 88% by a semiquantitative chemiluminescent immunoassay. The seroprevalence for antinucleocapsid was 20%. In addition, individuals with previous natural COVID-19 infection plus vaccination had higher anti-RBD antibody levels compared with those who had vaccination only or infection only. Individuals who had a breakthrough infection had the highest anti-RBD antibody levels. CONCLUSION: Accurate estimates of the cumulative incidence of SARS-CoV-2 infection can inform the development of university risk mitigation protocols such as encouraging booster shots, extending mask mandates or reverting to online classes. It could help us to have clear guidance to act at the first sign of the next surge as well, especially since there is a surge of COVID-19 subvariant infections.

Elucidating symptoms of COVID-19 illness in the Arizona CoVHORT: a longitudinal cohort study.

OBJECTIVE: To elucidate the symptoms of laboratory-confirmed COVID-19 cases as compared with laboratory-confirmed negative individuals and to the untested general population among all participants who reported symptoms within a large prospective cohort study. SETTING AND DESIGN: This work was conducted within the framework of the Arizona CoVHORT, a longitudinal prospective cohort study conducted among Arizona residents. PARTICIPANTS: Eligible participants were any individual living in Arizona and were recruited from across Arizona via COVID-19 case investigations, participation in testing studies and a postcard mailing effort. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was a comparison of the type and frequency of symptoms between COVID-19-positive cases, tested but negative individuals and the general untested population who reported experiencing symptoms consistent with COVID-19. RESULTS: Of the 1335 laboratory-confirmed COVID-19 cases, 180 (13.5%) reported having no symptoms. Of those that did report symptoms, the most commonly reported were fatigue (82.2%), headache (74.6%), aches, pains or sore muscles (66.3%), loss of taste or smell (62.8) and cough (61.9%). In adjusted logistic regression models, COVID-19-positive participants were more likely than negative participants to experience loss of taste and smell (OR 12.1; 95% CI 9.6 to 15.2), bone or nerve pain (OR 3.0; 95% CI 2.2 to 4.1), headache (OR 2.6; 95% CI 2.2 to 3.2), nausea (OR 2.4; 95% CI 1.9 to 3.1) or diarrhoea (OR 2.1; 95% CI 1.7 to 2.6). Fatigue (82.9) and headache (74.9) had the highest sensitivities among symptoms, while loss of taste or smell (87.2) and bone or nerve pain (92.9) had the high specificities among significant symptoms associated with COVID-19. CONCLUSION: When comparing confirmed COVID-19 cases with either confirmed negative or untested participants, the pattern of symptoms that discriminates SARS-CoV-2 infection from those arising from other potential circulating pathogens may differ from general reports of symptoms among cases alone.

Effect of school closure on the incidence of influenza among school-age children in Arizona.

OBJECTIVE: We assessed the impact of school closures as a viable intervention in the event of an influenza pandemic. METHODS: We evaluated the effect of scheduled, two-week winter break school closures during the 2004-2008 school years on the occurrence of influenza among children aged 5-17 years in Arizona. RESULTS: We found a consistent pattern of benefit to school-age children during winter school closures when non-school-age children and adults experienced significant increases in influenza incidence, an increase not seen among school-age children. Quantitative analysis showed that school closures may prevent or delay as much as 42% of potential influenza cases among school-age children. In addition, the ratio of illness in school-age children as compared with adults and non-school-age children decreased significantly from before to during the same school closure periods. CONCLUSION: This analysis provides evidence to suggest that school-age children may experience a slowing of influenza transmission during winter school closures compared with those not of school age. Federal, state, and local policy makers may consider these findings in their pandemic influenza and public health emergency preparedness planning efforts.

Does weight status influence perceptions of physical activity barriers among African-American women?

BACKGROUND: Many African-American women fail to participate in regular physical activity. Weight status may influence physical activity barriers. This study examined the frequency and type of barriers. METHODS: Participants in this study were enrolled in Project EXE-L (Exercising Ladies Excel), a six-month, church-based, randomized trial of moderate-intensity physical activity based in Baltimore city and county in Maryland. Participants were composed of African-American women who attended one of the participating churches, had friends who were church members, or who lived in neighborhoods surrounding one of the churches. Individuals who were between the ages of 25 and 70 years, were not regularly physically active (defined as not engaging in moderate-intensity activity more than three times per week), and were able to participate in moderate-intensity activity met eligibility criteria to participate in the trial. Barriers to physical activity were evaluated with the Steinhardt/Dishman Barriers for Habitual Physical Activity Scale at baseline. RESULTS: One hundred twenty women were classified as normal weight (body mass index [BMI]: <25 kg/m2), overweight (BMI: 25-29.9 kg/m2), or obese (BMI: > or = 30 kg/m2). Obese participants were more likely to report "lack of motivation" as a barrier compared with normal-weight participants (63% vs 31%). Normal-weight and overweight participants were more likely to report no barriers compared with the obese (31%, 0%, 5%, respectively, P<.05). CONCLUSIONS: Barriers for African-American women may vary by BMI status. By defining these unique barriers, effective physical activity interventions can be developed.

Racial differences in diurnal blood pressure and heart rate patterns: results from the Dietary Approaches to Stop Hypertension (DASH) trial.

BACKGROUND: Several studies have suggested that blacks, on average, have a blunted decline in nocturnal blood pressure (BP) as compared with nonblacks. It is unknown whether differences in traditional determinants of BP, specifically diet and obesity, account for observed differences in diurnal patterns. METHODS: We conducted an analysis of the Dietary Approaches to Stop Hypertension (DASH) trial that enrolled adults with prehypertension or stage 1 hypertension. At the end of a 3-week run-in period, ambulatory BP monitoring data were obtained on 333 participants, all of whom ate the same diet. Mean ambulatory daytime (6 am-11 pm) and nighttime (11 pm-6 am) systolic BP, diastolic BP, and heart rate (HR) were measured. Dipping was defined as a nighttime drop of less than 10% from mean daytime values. RESULTS: Office BP was similar in blacks and nonblacks, as were 24-hour and daytime BP and HR. However, blacks demonstrated a statistically significant, blunted nocturnal decline in BP and HR. Blacks were significantly more likely than nonblacks to have systolic nondipping (44.9% vs 26.7%, P = .001), diastolic nondipping (20.9% vs 11.6%, P = .03), and HR nondipping (40.9% vs 19.9%, P < .001). These differences persisted after adjustment for site, sex, age, body mass index, alcohol intake, physical activity, office BP (or HR), education, and income. CONCLUSION: Blacks with similar office BP, and who consumed the same diet as nonblacks, had a blunted nocturnal decline in systolic BP, diastolic BP, and HR, even after factors that influence BP were controlled for.

A prospective study of plasma ferritin level and incident diabetes: the Atherosclerosis Risk in Communities (ARIC) Study.

The authors performed a case-cohort study nested within the Atherosclerosis Risk in Communities (ARIC) Study to determine the association between plasma ferritin level and risk of type 2 diabetes mellitus. Persons with incident cases of type 2 diabetes diagnosed over an average follow-up period of 7.9 years (n = 599) were compared with a random sample of the cohort (n = 690). After adjustment for age, gender, menopausal status, ethnicity, center, smoking, and alcohol intake, the hazard ratio for diabetes, comparing the fifth quintile of ferritin with the first quintile, was 1.74 (95% confidence interval: 1.14, 2.65; p-trend < 0.001). After further adjustment for body mass index and components of the metabolic syndrome, the hazard ratio was 0.81 (95% confidence interval: 0.49, 1.34; p-trend = 0.87). From a causal perspective, there are two alternative interpretations of these findings. Elevated iron stores, reflected in elevated plasma ferritin levels, may induce baseline metabolic abnormalities that ultimately result in diabetes. Alternatively, elevated ferritin may be just one of several metabolic abnormalities related to the underlying process that ultimately results in diabetes, rather than a causal factor for diabetes. Longitudinal studies with repeated measurements of glucose and iron metabolism parameters are needed to establish the role of iron stores and plasma ferritin in diabetes development.

Prevalence of overweight among Baltimore City schoolchildren and its associations with nutrition and physical activity.

OBJECTIVE: To determine the prevalence of overweight and at-risk-for-overweight in schoolchildren from Baltimore City. RESEARCH METHODS AND PROCEDURES: Ten schools within city limits were randomly selected from each tertile of income, using eligibility for free school lunch as a proxy. A total of 209 third grade students from eight public schools in Baltimore City were surveyed in May 2000. Anthropometric data including height, weight, subscapular and triceps skinfold thickness, and percentage body weight from bioelectrical impedance were collected. Nutrition-related knowledge, attitudes, and behaviors were assessed using a validated questionnaire. Physical activity was assessed by questionnaire. RESULTS: Based on International Obesity Taskforce reference values for BMI-for-age, 20.7% of girls and 17.2% of boys were overweight (BMI > 95th percentile) and 15.3% of girls and 14.1% of boys were at-risk-for-overweight (BMI between the 85th and 95th percentiles). The prevalence of overweight and at-risk-for-overweight did not vary by self-reported physical activity levels or by nutrition-related knowledge and behaviors. DISCUSSION: The high prevalence of overweight and at-risk-for-overweight in this sample of inner-city children from Baltimore City highlights a need for targeted preventive and treatment interventions.

New high blood pressure guidelines create new at-risk classification: changes in blood pressure classification by JNC 7.

High blood pressure has become increasingly prevalent and is an important risk factor for cardiovascular disease. The Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) has redefined normal blood pressure as less than 120/80 mm Hg and created a new blood pressure category called "prehypertension" for those with a systolic BP of 120 to 139 mm Hg or a diastolic BP of 80 to 89 mm Hg. This new blood pressure category was created to identify adults considered to be at risk for developing hypertension and to alert both patients and healthcare providers of the importance of adopting lifestyle changes. Recognition of prehypertension provides important opportunities to prevent hypertension and cardiovascular disease.