Real-Time Use of a Dynamic Model To Measure the Impact of Public Health Interventions on Measles Outbreak Size and Duration - Chicago, Illinois, 2024.

Measles is a highly infectious, vaccine-preventable disease that can cause severe illness, hospitalization, and death. A measles outbreak associated with a migrant shelter in Chicago occurred during February-April 2024, in which a total of 57 confirmed cases were identified, including 52 among shelter residents, three among staff members, and two among community members with a known link to the shelter. CDC simulated a measles outbreak among shelter residents using a dynamic disease model, updated in real time as additional cases were identified, to produce outbreak forecasts and assess the impact of public health interventions. As of April 8, the model forecasted a median final outbreak size of 58 cases (IQR = 56-60 cases); model fit and prediction range improved as more case data became available. Counterfactual analysis of different intervention scenarios demonstrated the importance of early deployment of public health interventions in Chicago, with a 69% chance of an outbreak of 100 or more cases had there been no mass vaccination or active case-finding compared with only a 1% chance when those interventions were deployed. This analysis highlights the value of using real-time, dynamic models to aid public health response, set expectations about outbreak size and duration, and quantify the impact of interventions. The model shows that prompt mass vaccination and active case-finding likely substantially reduced the chance of a large (100 or more cases) outbreak in Chicago.

Measles Outbreak Associated with a Migrant Shelter - Chicago, Illinois, February-May 2024.

Measles, a highly contagious respiratory virus with the potential to cause severe complications, hospitalization, and death, was declared eliminated from the United States in 2000; however, with ongoing global transmission, infections in the United States still occur. On March 7, 2024, the Chicago Department of Public Health (CDPH) confirmed a case of measles in a male aged 1 year residing in a temporary shelter for migrants in Chicago. Given the congregate nature of the setting, high transmissibility of measles, and low measles vaccination coverage among shelter residents, measles virus had the potential to spread rapidly among approximately 2,100 presumed exposed shelter residents. CDPH immediately instituted outbreak investigation and response activities in collaboration with state and local health departments, health care facilities, city agencies, and shelters. On March 8, CDPH implemented active case-finding and coordinated a mass vaccination campaign at the affected shelter (shelter A), including vaccinating 882 residents and verifying previous vaccination for 784 residents over 3 days. These activities resulted in 93% measles vaccination coverage (defined as receipt of ≥1 recorded measles vaccine dose) by March 11. By May 13, a total of 57 confirmed measles cases associated with residing in or having contact with persons from shelter A had been reported. Most cases (41; 72%) were among persons who did not have documentation of measles vaccination and were considered unvaccinated. In addition, 16 cases of measles occurred among persons who had received ≥1 measles vaccine dose ≥21 days before first known exposure. This outbreak underscores the need to ensure high vaccination coverage among communities residing in congregate settings.

Measuring Work-related Risk of Coronavirus Disease 2019 (COVID-19): Comparison of COVID-19 Incidence by Occupation and Industry-Wisconsin, September 2020 to May 2021.

BACKGROUND: Work-related exposures play an important role in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission, yet few studies have compared SARS-CoV-2 expsoure risk across occupations and industries. METHODS: During September 2020 to May 2021, the Wisconsin Department of Health Services collected occupation and industry data as part of routine coronavirus disease 2019 (COVID-19) case investigations. Adults aged 18-64 years with confirmed or probable COVID-19 in Wisconsin were assigned standardized occupation and industry codes. Cumulative incidence rates were weighted for non-response and calculated using full-time equivalent (FTE) workforce denominators from the 2020 American Community Survey. RESULTS: An estimated 11.6% of workers (347 013 of 2.98 million) in Wisconsin, ages 18-64 years, had COVID-19 from September 2020 to May 2021. The highest incidence by occupation (per 100 FTE) occurred among personal care and services workers (22.1), healthcare practitioners and support staff (20.7), and protective services workers (20.7). High-risk sub-groups included nursing assistants and personal care aides (28.8), childcare workers (25.8), food and beverage service workers (25.3), personal appearance workers (24.4), and law enforcement workers (24.1). By industry, incidence was highest in healthcare (18.6); the highest risk sub-sectors were nursing care facilities (30.5) and warehousing (28.5). CONCLUSIONS: This analysis represents one of the most complete examinations to date of COVID-19 incidence by occupation and industry. Our approach demonstrates the value of standardized occupational data collection by public health and may be a model for improved occupational surveillance elsewhere. Workers at higher risk of SARS-CoV-2 exposure may benefit from targeted workplace COVID-19 vaccination and mitigation efforts.

Wastewater Surveillance Data as a Complement to Emergency Department Visit Data for Tracking Incidence of Influenza A and Respiratory Syncytial Virus - Wisconsin, August 2022-March 2023.

Wastewater surveillance has been used to assist public health authorities in tracking local transmission of SARS-CoV-2. The usefulness of wastewater surveillance to track community spread of other respiratory pathogens, including influenza virus and respiratory syncytial virus (RSV), is less clear. During the 2022-23 respiratory diseases season, concentrations of influenza A virus and RSV in wastewater samples in three major Wisconsin cities were compared with emergency department (ED) visits associated with these pathogens. In all three cities, higher concentrations of influenza A virus and RSV in wastewater were associated with higher numbers of associated ED visits (Kendall's tau range = 0.50-0.63 for influenza-associated illness and 0.30-0.49 for RSV-associated illness). Detections of both influenza A virus and RSV in wastewater often preceded a rise in associated ED visits for each pathogen, and virus material remained detectable in wastewater for up to 3 months after pathogen-specific ED visits declined. These results demonstrate that wastewater surveillance has the potential to complement conventional methods of influenza and RSV surveillance, detecting viral signals earlier and for a longer duration than do clinical data. Continued use of wastewater surveillance as a supplement to established surveillance systems such as ED visits might improve local understanding and response to seasonal respiratory virus outbreaks.

Assessment of Anti-SARS-CoV-2 antibody levels among university students vaccinated with different COVID-19 primary and booster doses - fall 2021, Wisconsin.

BACKGROUND: University students commonly received COVID-19 vaccinations before returning to U.S. campuses in the Fall of 2021. Given likely immunologic variation among students based on differences in type of primary series and/or booster dose vaccine received, we conducted serologic investigations in September and December 2021 on a large university campus in Wisconsin to assess anti-SARS-CoV-2 antibody levels. METHODS: We collected blood samples, demographic information, and COVID-19 illness and vaccination history from a convenience sample of students. Sera were analyzed for both anti-spike (anti-S) and anti-nucleocapsid (anti-N) antibody levels using World Health Organization standardized binding antibody units per milliliter (BAU/mL). Levels were compared across categorical primary COVID-19 vaccine series received and binary COVID-19 mRNA booster status. The association between anti-S levels and time since most recent vaccination dose was estimated by mixed-effects linear regression. RESULTS: In total, 356 students participated, of whom 219 (61.5%) had received a primary vaccine series of Pfizer-BioNTech or Moderna mRNA vaccines and 85 (23.9%) had received vaccines from Sinovac or Sinopharm. Median anti-S levels were significantly higher for mRNA primary vaccine series recipients (2.90 and 2.86 log [BAU/mL], respectively), compared with those who received Sinopharm or Sinovac vaccines (1.63 and 1.95 log [BAU/mL], respectively). Sinopharm and Sinovac vaccine recipients were associated with a significantly faster anti-S decline over time, compared with mRNA vaccine recipients (P <.001). By December, 48/172 (27.9%) participants reported receiving an mRNA COVID-19 vaccine booster, which reduced the anti-S antibody discrepancies between primary series vaccine types. CONCLUSIONS: Our work supports the benefit of heterologous boosting against COVID-19. COVID-19 mRNA vaccine booster doses were associated with increases in anti-SARS-CoV-2 antibody levels; following an mRNA booster dose, students with both mRNA and non-mRNA primary series receipt were associated with comparable levels of anti-S IgG.

The variant-specific burden of SARS-CoV-2 in Michigan: March 2020 through November 2021.

Accurate estimates of the total burden of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are needed to inform policy, planning, and response. We sought to quantify SARS-CoV-2 cases, hospitalizations, and deaths by age in Michigan. Coronavirus disease 2019 cases reported to the Michigan Disease Surveillance System were multiplied by age and time-specific adjustment factors to correct for under-detection. Adjustment factors were estimated in a model fit to incidence data and seroprevalence estimates. Age-specific incidence of SARS-CoV-2 hospitalization, death, vaccination, and variant proportions were estimated from publicly available data. We estimated substantial under-detection of infection that varied by age and time. Accounting for under-detection, we estimate the cumulative incidence of infection in Michigan reached 75% by mid-November 2021, and over 87% of Michigan residents were estimated to have had ≥1 vaccination dose and/or previous infection. Comparing pandemic waves, the relative burden among children increased over time. In general, the proportion of cases who were hospitalized or who died decreased over time. Our results highlight the ongoing risk of periods of high SARS-CoV-2 incidence despite widespread prior infection and vaccination. This underscores the need for long-term planning for surveillance, vaccination, and other mitigation measures amidst continued response to the acute pandemic.

School District Prevention Policies and Risk of COVID-19 Among In-Person K-12 Educators, Wisconsin, 2021.

Objectives. To assess the rate of COVID-19 among in-person K-12 educators and the rate's association with various COVID-19 prevention policies in school districts. Methods. We linked actively working, in-person K-12 educators in Wisconsin to COVID-19 cases with onset from September 2 to November 24, 2021. A mixed-effects Cox proportional hazards model, adjusted for pertinent person- and community-level confounders, compared the hazard rate of COVID-19 among educators working in districts with and without specific COVID-19 prevention policies. Results. In-person educators working in school districts that required masking for students and staff experienced 19% lower hazards of COVID-19 than did those in districts without any masking policy (hazard ratio = 0.81; 95% confidence interval = 0.72, 0.92). Reduced COVID-19 hazards were consistent and remained statistically significant when educators were stratified by elementary, middle, and high school environments. Conclusions. In Wisconsin's K-12 school districts, during the fall 2021 academic semester, a policy that required both students and staff to mask was associated with significantly reduced risk of COVID-19 among in-person educators across all grade levels. (Am J Public Health. 2022;112(12):1791-1799. https://doi.org/10.2105/AJPH.2022.307095).

Coronavirus Occurrence and Transmission Over 8 Years in the HIVE Cohort of Households in Michigan.

BACKGROUND: As part of the Household Influenza Vaccine Evaluation (HIVE) study, acute respiratory infections (ARI) have been identified in children and adults from 2010 to 2018. METHODS: Annually, 890 to 1441 individuals were followed and contacted weekly to report ARIs. Specimens collected during illness were tested for human coronaviruses (HCoV) types OC43, 229E, HKU1, and NL63. RESULTS: In total, 993 HCoV infections were identified during the 8 years, with OC43 most commonly seen and 229E the least. HCoVs were detected in a limited time period, between December and April/May and peaked in January/February. Highest infection frequency was in children <5 years (18 per 100 person-years), with little variation in older age groups (range, 7 to 11 per 100 person-years). Overall, 9% of adult cases and 20% of cases in children were associated with medical consultation. Of the 993 infections, 260 were acquired from an infected household contact. The serial interval between index and household-acquired cases ranged from 3.2 to 3.6 days and the secondary infection risk ranged from 7.2% to 12.6% by type. CONCLUSIONS: Coronaviruses are sharply seasonal. They appear, based on serial interval and secondary infection risk, to have similar transmission potential to influenza A(H3N2) in the same population.

Biological concepts in human sodium channel epilepsies and their relevance in clinical practice.

OBJECTIVE: Voltage-gated sodium channels (SCNs) share similar amino acid sequence, structure, and function. Genetic variants in the four human brain-expressed SCN genes SCN1A/2A/3A/8A have been associated with heterogeneous epilepsy phenotypes and neurodevelopmental disorders. To better understand the biology of seizure susceptibility in SCN-related epilepsies, our aim was to determine similarities and differences between sodium channel disorders, allowing us to develop a broader perspective on precision treatment than on an individual gene level alone. METHODS: We analyzed genotype-phenotype correlations in large SCN-patient cohorts and applied variant constraint analysis to identify severe sodium channel disease. We examined temporal patterns of human SCN expression and correlated functional data from in vitro studies with clinical phenotypes across different sodium channel disorders. RESULTS: Comparing 865 epilepsy patients (504 SCN1A, 140 SCN2A, 171 SCN8A, four SCN3A, 46 copy number variation [CNV] cases) and analysis of 114 functional studies allowed us to identify common patterns of presentation. All four epilepsy-associated SCN genes demonstrated significant constraint in both protein truncating and missense variation when compared to other SCN genes. We observed that age at seizure onset is related to SCN gene expression over time. Individuals with gain-of-function SCN2A/3A/8A missense variants or CNV duplications share similar characteristics, most frequently present with early onset epilepsy (<3 months), and demonstrate good response to sodium channel blockers (SCBs). Direct comparison of corresponding SCN variants across different SCN subtypes illustrates that the functional effects of variants in corresponding channel locations are similar; however, their clinical manifestation differs, depending on their role in different types of neurons in which they are expressed. SIGNIFICANCE: Variant function and location within one channel can serve as a surrogate for variant effects across related sodium channels. Taking a broader view on precision treatment suggests that in those patients with a suspected underlying genetic epilepsy presenting with neonatal or early onset seizures (<3 months), SCBs should be considered.

Communicable Disease Outbreaks in Michigan Child Care Centers Compared With State and Regional Epidemics, 2014-2017.

The Michigan Child Care Related Infections Surveillance Program (MCRISP) is a novel, online illness surveillance system used by a collection of southeast Michigan child care centers. Recently established, MCRISP has not been assessed epidemiologically. We created MCRISP epidemic curves for both respiratory and gastrointestinal disease over three seasons, comparing these to data from an established statewide surveillance system. Results suggest that online child care center-based disease surveillance is timely, functional, and has potential as an early sentinel system for community epidemics.

Using wastewater surveillance for mpox as a complement to traditional case-based reporting - Chicago, March-June 2023.

The Chicago Department of Public Health tested wastewater samples for the presence of Monkeypox Virus (MPXV) from March 13 through June 26, 2023. There were persistent detections prior to reported cases. This indicated the baseline levels of MPXV prevalence might warrant routine monitoring. Detections in areas without corresponding reported clinical cases might highlight areas where cases are being under-reported by traditional surveillance.

Description of Kratom Exposure Events in Wisconsin as Reported to the Wisconsin Poison Center, January 1, 2010 to September 1, 2022.

BACKGROUND: Consumption of kratom (Mitragyna speciosa), an herbal substance, can result in adverse health effects. We characterized kratom-associated adverse events in Wisconsin to provide pertinent recommendations for clinicians and public health practitioners. METHODS: Using Wisconsin Poison Center data, we searched for and summarized all records associated with exposure to "kratom," "electronic delivery device containing kratom," or "mitragyna" from January 1, 2010, to September 1, 2022. RESULTS: Kratom-associated exposure calls to the Wisconsin Poison Center increased 3.75 times during 2016 - 2020. Among all 59 calls, 26 (44.1%) reported concomitant use of another substance, agitation was the most common symptom reported (n = 23, 39%), and 7 persons required critical care. Three unintentional ingestions were reported in children aged less than 2 years old. DISCUSSION: Kratom-associated exposure calls to the Wisconsin Poison Center generally have been increasing in frequency since 2011. Wisconsinites who choose to use kratom might benefit from education regarding health risks and safe storage practices to avoid unintentional pediatric exposure.

Comparing the Etiology of Viral Acute Respiratory Illnesses Between Children Who Do and Do Not Attend Childcare.

BACKGROUND AND OBJECTIVE: Childcare attendance is a common risk factor for acute respiratory illness (ARI) in young children. Our goal was to better understand the specific respiratory viruses that predominate in childcare, which may support the development of tailored illness prevention and intervention strategies in childcare settings. METHODS: Using data from a prospective household cohort of ARI surveillance, we assessed specimen from 1418 ARIs reported by 359 childcare-aged children over 6 study seasons (2012/2013 through 2017/2018). Respiratory swabs were tested by polymerase chain reaction for 9 respiratory viruses. A mixed-effect logistic regression model was used to compare odds of various viral detection outcomes. The Shannon's Diversity index was used to compare the richness (ie, number of species) and diversity (ie, relative species abundance) associated with respiratory viruses detected in both groups. RESULTS: At least 1 virus was detected in 75.5% of childcare-associated ARIs and in 80.1% of homecare ARIs. Compared with illnesses among homecare children, childcare illnesses were associated with significantly higher odds of detected adenovirus (odds ratio = 1.86, 95% confidence interval = 1.05-3.28) and human metapneumovirus (odds ratio = 1.76, 95% confidence interval = 1.03-3.0). The pool of viruses associated with childcare ARI was found to be significantly richer and more diverse than that of viruses associated with homecare ARI ( P < 0.0001). CONCLUSIONS: Children attending childcare experience a higher risk of adenovirus and human metapneumovirus infection and are regularly exposed to a rich and diverse pool of respiratory viruses in childcare environments. Our results underscore the necessity of thorough and multifaceted viral prevention strategies in childcare settings.

Using the MCRISP Network for Surveillance of Pediatric Exanthema in Child Care Centers.

BACKGROUND: Systematic monitoring of exanthema is largely absent from public health surveillance despite emerging diseases and threats of bioterrorism. Michigan Child Care Related Infections Surveillance Program (MCRISP) is the first online program in child care centers to report pediatric exanthema. METHODS: MCRISP aggregated daily counts of children sick, absent, or reported ill by parents. We extracted all MCRISP exanthema cases from October 1, 2014 through June 30, 2019. Cases were assessed with descriptive statistics and counts were used to construct epidemic curves. RESULTS: 360 exanthema cases were reported from 12,233 illnesses over 4.5 seasons. Children ages 13-35 months had the highest rash occurrence (45%, n = 162), followed by 36-59 months (41.7%, n = 150), 0-12 months (12.5%, n = 45), and kindergarten (0.8%, n = 3). Centers reported rashes of hand-foot-mouth disease (50%, n = 180), nonspecific rash without fever (15.3%, n = 55), hives (8.1%, n = 29), fever with nonspecific rash (6.9%, n = 25), roseola (3.3%, n = 12), scabies (2.5%, n = 9), scarlet fever (2.5%, n = 9), impetigo (2.2%, n = 8), abscess (1.95, n = 7), viral exanthema without fever (1.7%, n = 6), varicella (1.7%, n = 6), pinworms (0.8%, n = 3), molluscum (0.6%, n = 2), cellulitis (0.6%, n = 2), ringworm (0.6%, n = 2), and shingles (0.2%, n = 1). CONCLUSION: Child care surveillance networks have the potential to act as sentinel public health tools for surveillance of pediatric exanthema outbreaks.

Distinct influenza surveillance networks and their agreement in recording regional influenza circulation: Experience from Southeast Michigan.

INTRODUCTION: In Southeast Michigan, active surveillance studies monitor influenza activity in hospitals, ambulatory clinics, and community households. Across five respiratory seasons, we assessed the contribution of data from each of the three networks towards improving our overall understanding of regional influenza circulation. METHODS: All three networks used case definitions for acute respiratory illness (ARI) and molecularly tested for influenza from research-collected respiratory specimens. Age- and network-stratified epidemic curves were created for influenza A and B. We compared stratified epidemic curves visually and by centering at seasonal midpoints. RESULTS: Across all seasons (from 2014/2015 through 2018/2019), epidemic curves from each of the three networks were comparable in terms of both timing and magnitude. Small discrepancies in epidemics recorded by each network support previous conclusions about broader characteristics of particular influenza seasons. CONCLUSION: Influenza surveillance systems based in hospital, ambulatory clinic, and community household settings appear to provide largely similar information regarding regional epidemic activity. Together, multiple levels of influenza surveillance provide a detailed view of regional influenza epidemics, but a single surveillance system-regardless of population subgroup monitored-appears to be sufficient in providing vital information regarding community influenza epidemics.

Expanding Surveillance Toward Sharing Data with the Community: Qualitative Insights from a Childcare Center Illness Surveillance Program.

Childcare attendance is a recognized independent risk factor for pediatric infectious diseases due to the pathogen-sharing behaviors of young children and the crowded environments of childcare programs. The Michigan Child Care Related Infections Surveillance Program (MCRISP) is a novel online illness surveillance network used by community childcare centers to track disease incidence. It has been used to warn local public health departments about emerging outbreaks. The flow of data from MCRISP, however, remains largely unidirectional-from data reporter to public health researchers. With the intent to ultimately improve the system for users, we wanted to better understand how community illness data collected by MCRISP might best benefit childcare stakeholders themselves. Using a ground-up design approach, we conducted a series of focus groups among childcare directors participating in MCRISP. All primary data reporters from each of the 30 MCRISP-affiliated childcare centers were eligible to participate in the focus groups. A thematic assessment from the focus groups revealed that participants wanted surveillance system improvements that would (1) support subjective experiences with objective data, (2) assist with program decision making, (3) provide educational resources, and (4) prioritize the user's experience. Our findings support a framework by which community disease surveillance networks can move toward greater transparency and 2-way data flow. Ultimately, a more mutually beneficial surveillance system improves stakeholder engagement, provides opportunities for rapid mitigation strategies, and can help allocate timely resources in responding to emerging outbreaks and pandemics.

Variation in surface decontamination practices among Michigan child care centers compared to state and national guidelines.

BACKGROUND: Environmental decontamination is one of the most effective methods to prevent transmission of infectious pathogens in child care centers (CCCs). Alongside state recommendations, national organizations-including the American Academy of Pediatrics (AAP)-offer best-practice policies. In Michigan, these sets of guidelines differ, and the extent to which CCC practices agree with either set of protocols is unknown. METHODS: A survey of environmental decontamination practices was administered at a professional meeting of CCC directors (N = 24) in a single Michigan county. CCC practices (eg, products, locations, frequencies) were compared to state and AAP guidelines. Bivariate analyses investigated CCC characteristics as predictors of decontamination policy agreement. RESULTS: CCC agreement with established policy was slightly higher for national AAP guidelines (66%) than Michigan standards (59%). The use of an outside child care health consultant was strongly associated with a significantly higher level of agreement with state decontamination policy (P = .01). CONCLUSION: We noted substantial disagreement between county CCC practices and state/national guidelines, regardless of CCC size or director experience. Results highlight opportunities to improve CCC director familiarity with current state and nationally advised protocols, to consolidate state licensing and AAP guidelines, and to promote the use of child care health consultants.