Measles and Rubella Diagnostic and Classification Challenges in Near- and Post-Elimination Countries.

Measles and rubella are vaccine-preventable viral diseases and can be prevented by safe, highly effective vaccination with measles- and rubella-containing vaccines. Given the myriad causes of febrile exanthems, laboratory surveillance for both measles and rubella is important to document the incidence of these diseases and to track the progress and maintenance of elimination in near- and post-elimination settings. Diagnostic challenges can hinder effective surveillance and classification challenges can hinder efforts to demonstrate achievement or maintenance of elimination. In this report, we review diagnostic and classification challenges for measles and rubella in near- and post-elimination settings.

Sociodemographic Trends and Correlation between Parental Hesitancy towards Pediatric COVID-19 Vaccines and Routine Childhood Immunizations in the United States: 2021-2022 National Immunization Survey-Child COVID Module.

Multiple factors may influence parental vaccine hesitancy towards pediatric COVID-19 vaccines and routine childhood immunizations (RCIs). Using the United States National Immunization Survey-Child COVID Module data collected from parents/guardians of children aged 5-11 years, this cross-sectional study (1) identified the trends and prevalence estimates of parental hesitancy towards pediatric COVID-19 vaccines and RCIs, (2) examined the relationship between hesitancy towards pediatric COVID-19 vaccines and RCIs, and (3) assessed trends in parental hesitancy towards RCIs by sociodemographic characteristics and behavioral and social drivers of COVID-19 vaccination. From November 2021 to July 2022, 54,329 parents or guardians were interviewed. During this 9-month period, the proportion of parents hesitant about pediatric COVID-19 vaccines increased by 15.8 percentage points (24.8% to 40.6%). Additionally, the proportion of parents who reported RCIs hesitancy increased by 4.7 percentage points from November 2021 to May 2022 but returned to baseline by July 2022. Over nine months, parents' concerns about pediatric COVID-19 infections declined; however, parents were increasingly worried about pediatric COVID-19 vaccine safety and overall importance. Furthermore, pediatric COVID-19 vaccine hesitancy was more prevalent among parents of children who were White (43.2%) versus Black (29.3%) or Hispanic (26.9%) and those residing in rural (51.3%) compared to urban (28.9%) areas. In contrast, RCIs hesitancy was higher among parents of children who were Black (32.0%) versus Hispanic (24.5%) or White (23.6%). Pediatric COVID-19 vaccine hesitancy was 2-6 times as prevalent among parents who were RCIs hesitant compared to those who were RCIs non-hesitant. This positive correlation between parental hesitancy towards pediatric COVID-19 vaccines and RCIs was observed for all demographic and psychosocial factors for unadjusted and adjusted prevalence ratios. Parent-provider interactions should increase vaccine confidence, shape social norms, and facilitate behavior change to promote pediatric vaccination rates.

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.

Measles - United States, January 1, 2020-March 28, 2024.

Measles is a highly infectious febrile rash illness and was declared eliminated in the United States in 2000. However, measles importations continue to occur, and U.S. measles elimination status was threatened in 2019 as the result of two prolonged outbreaks among undervaccinated communities in New York and New York City. To assess U.S. measles elimination status after the 2019 outbreaks and to provide context to understand more recent increases in measles cases, CDC analyzed epidemiologic and laboratory surveillance data and the performance of the U.S. measles surveillance system after these outbreaks. During January 1, 2020-March 28, 2024, CDC was notified of 338 confirmed measles cases; 97 (29%) of these cases occurred during the first quarter of 2024, representing a more than seventeenfold increase over the mean number of cases reported during the first quarter of 2020-2023. Among the 338 reported cases, the median patient age was 3 years (range = 0-64 years); 309 (91%) patients were unvaccinated or had unknown vaccination status, and 336 case investigations included information on ≥80% of critical surveillance indicators. During 2020-2023, the longest transmission chain lasted 63 days. As of the end of 2023, because of the absence of sustained measles virus transmission for 12 consecutive months in the presence of a well-performing surveillance system, U.S. measles elimination status was maintained. Risk for widespread U.S. measles transmission remains low because of high population immunity. However, because of the increase in cases during the first quarter of 2024, additional activities are needed to increase U.S. routine measles, mumps, and rubella vaccination coverage, especially among close-knit and undervaccinated communities. These activities include encouraging vaccination before international travel and rapidly investigating suspected measles cases.

Deaths Associated with Pediatric Hepatitis of Unknown Etiology, United States, October 2021-June 2023.

During October 2021-June 2023, a total of 392 cases of acute hepatitis of unknown etiology in children in the United States were reported to Centers for Disease Control and Prevention as part of national surveillance. We describe demographic and clinical characteristics, including potential involvement of adenovirus in development of acute hepatitis, of 8 fatally ill children who met reporting criteria. The children had diverse courses of illness. Two children were immunocompromised when initially brought for care. Four children tested positive for adenovirus in multiple specimen types, including 2 for whom typing was completed. One adenovirus-positive child had no known underlying conditions, supporting a potential relationship between adenovirus and acute hepatitis in previously healthy children. Our findings emphasize the importance of continued investigation to determine the mechanism of liver injury and appropriate treatment. Testing for adenovirus in similar cases could elucidate the role of the virus.

Long-term Neutralizing Antibody Levels Against Measles and Rubella Viruses Among Adults With 3 Doses of Measles-Mumps-Rubella Vaccine.

Background: A third dose of measles-mumps-rubella vaccine (MMR) may be administered for various reasons, but data on long-term immunity are limited. We assessed neutralizing antibody levels against measles and rubella among adults up to 11 years after receipt of a third MMR dose. Methods: In this longitudinal study, healthy adults who received a third MMR dose as young adults (ages 18-28 years) were recalled around 5 years and 9-11 years after the third dose. Measles and rubella antibody levels were assessed by plaque-reduction and immunocolorimetric neutralization assays, respectively. Antibody concentrations <120 mIU/mL and <10 U/mL were considered potentially susceptible to measles and rubella, respectively. Geometric mean concentrations (GMCs) and 95% confidence intervals (CIs) over time were estimated from generalized estimating equation models. Results: Approximately 5 and 9-11 years after receipt of the third dose, 405 and 304 adults were assessed, respectively. Measles GMC was 428 mIU/mL (95% CI, 392-468 mIU/mL) 5 years postvaccination, declining to 381 mIU/mL (95% CI, 339-428 mIU/mL) 11 years postvaccination. At the last follow-up visit (9-11 years postvaccination), 10% of participants were potentially susceptible to measles infection. Rubella GMCs were stable throughout the follow-up period (63 U/mL to 65 U/mL); none of the participants was susceptible to rubella at the last follow-up visit. Conclusions: Eleven years after receiving a third MMR dose, measles and rubella neutralizing antibody levels remained high in adults. However, on the basis of waning antibody levels, some adults may become susceptible to measles infection over time despite receipt of 3 vaccine doses.

Modeling Poliovirus Transmission and Responses in New York State.

BACKGROUND: In July 2022, New York State (NYS) reported a case of paralytic polio in an unvaccinated young adult, and subsequent wastewater surveillance confirmed sustained local transmission of type 2 vaccine-derived poliovirus (VDPV2) in NYS with genetic linkage to the paralyzed patient. METHODS: We adapted an established poliovirus transmission and oral poliovirus vaccine evolution model to characterize dynamics of poliovirus transmission in NYS, including consideration of the immunization activities performed as part of the declared state of emergency. RESULTS: Despite sustained transmission of imported VDPV2 in NYS involving potentially thousands of individuals (depending on seasonality, population structure, and mixing assumptions) in 2022, the expected number of additional paralytic cases in years 2023 and beyond is small (less than 0.5). However, continued transmission and/or reintroduction of poliovirus into NYS and other populations remains a possible risk in communities that do not achieve and maintain high immunization coverage. CONCLUSIONS: In countries such as the United States that use only inactivated poliovirus vaccine, even with high average immunization coverage, imported polioviruses may circulate and pose a small but nonzero risk of causing paralysis in nonimmune individuals.

Paediatric acute hepatitis of unknown aetiology: a national surveillance investigation in the USA during 2021 and 2022.

BACKGROUND: Adenovirus is a known cause of hepatitis in immunocompromised children, but not in immunocompetent children. In April, 2022, following multiple reports of hepatitis of unknown aetiology and adenovirus viraemia in immunocompetent children in the USA and UK, the US Centers for Disease Control and Prevention (CDC) and jurisdictional health departments initiated national surveillance of paediatric acute hepatitis of unknown aetiology. We aimed to describe the clinical and epidemiological characteristics of children identified with hepatitis of unknown aetiology between Oct 1, 2021, and Sept 30, 2022, in the USA and to compare characteristics of those who tested positive for adenovirus with those who tested negative. METHODS: In this national surveillance investigation in the USA, children were identified for investigation if they were younger than 10 years with elevated liver transaminases (>500 U/L) who had an unknown cause for their hepatitis and onset on or after Oct 1, 2021. We reviewed medical chart abstractions, which included data on demographics, underlying health conditions, signs and symptoms of illness, laboratory results, vaccination history, radiological and liver pathology findings, diagnoses and treatment received, and outcomes. Caregiver interviews were done to obtain information on symptoms and health-care utilisation for the hepatitis illness, medical history, illness in close contacts or at school or daycare, diet, travel, and other potential exposures. Blood, stool, respiratory, and tissue specimens were evaluated according to clinician discretion and available specimens were submitted to CDC for additional laboratory testing or pathology evaluation. FINDINGS: Surveillance identified 377 patients from 45 US jurisdictions with hepatitis of unknown aetiology with onset from Oct 1, 2021, to Sept 30, 2022. The median age of patients was 2·8 years (IQR 1·2-5·0) and 192 (51%) were male, 184 (49%) were female, and one patient had sex unknown. Only 22 (6%) patients had a notable predisposing underlying condition. 347 patients (92%) were admitted to hospital, 21 (6%) subsequently received a liver transplant, and nine (2%) died. Among the 318 patients without notable underlying conditions, 275 were tested for adenovirus. Of these 116 (42%) had at least one positive specimen, and species F type 41 was the most frequent type identified (19 [73%] of 26 typed specimens were HAdV-41). Proportions of patients who had acute liver failure, received a liver transplant, and died were similar between those who tested positive for adenovirus compared with those who tested negative. Adenovirus species F was detected by polymerase chain reaction in nine pathology liver evaluations, but not by immunohistochemistry in seven of the nine with adequate liver tissue available. Interviews with caregivers yielded no common exposures. INTERPRETATION: Adenovirus, alone or in combination with other factors, might play a potential role in acute hepatitis among immunocompetent children identified in this investigation, but the pathophysiologic mechanism of liver injury is unclear. To inform both prevention and intervention measures, more research is warranted to determine if and how adenovirus might contribute to hepatitis risk and the potential roles of other pathogens and host factors. FUNDING: None.

Measles virus transmission patterns and public health responses during Operation Allies Welcome: a descriptive epidemiological study.

BACKGROUND: On Aug 29, 2021, Operation Allies Welcome (OAW) was established to support the resettlement of more than 80 000 Afghan evacuees in the USA. After identification of measles among evacuees, incoming evacuee flights were temporarily paused, and mass measles vaccination of evacuees aged 6 months or older was introduced domestically and overseas, with a 21-day quarantine period after vaccination. We aimed to evaluate patterns of measles virus transmission during this outbreak and the impact of control measures. METHODS: We conducted a measles outbreak investigation among Afghan evacuees who were resettled in the USA as part of OAW. Patients with measles were defined as individuals with an acute febrile rash illness between Aug 29, 2021, and Nov 26, 2021, and either laboratory confirmation of infection or epidemiological link to a patient with measles with laboratory confirmation. We analysed the demographics and clinical characteristics of patients with measles and used epidemiological information and whole-genome sequencing to track transmission pathways. A transmission model was used to evaluate the effects of vaccination and other interventions. FINDINGS: 47 people with measles (attack rate: 0·65 per 1000 evacuees) were reported in six US locations housing evacuees in four states. The median age of patients was 1 year (range 0-26); 33 (70%) were younger than 5 years. The age distribution shifted during the outbreak towards infants younger than 12 months. 20 (43%) patients with wild-type measles virus had rash onset after vaccination. No fatalities or community spread were identified, nor further importations after flight resumption. In a non-intervention scenario, transmission models estimated that a median of 5506 cases (IQR 10-5626) could have occurred. Infection clusters based on epidemiological criteria could be delineated into smaller clusters using phylogenetic analyses; however, sequences with few substitution count differences did not always indicate single lines of transmission. INTERPRETATION: Implementation of control measures limited measles transmission during OAW. Our findings highlight the importance of integration between epidemiological and genetic information in discerning between individual lines of transmission in an elimination setting. FUNDING: US Centers for Disease Control and Prevention.

Early childhood outcomes of NICU graduates with cytomegalovirus infection in California.

BACKGROUND: To assess demographics and outcomes up to 3 years of age among children with cytomegalovirus (CMV) infection in California neonatal intensive care units (NICUs) during 2010-2021. METHODS: The California Perinatal Quality Care Collaborative (CPQCC) collects data on all very low birth weight (VLBW, birth weight ≤ 1500 g) and acutely ill infants with birth weight > 1500 g across 92% of NICUs in California. VLBW infants and those with neurological conditions are referred to a statewide high-risk infant follow-up (HRIF) program. CMV infection was defined as a positive culture or PCR identified during the NICU hospitalization. RESULTS: During 2010-2021, CMV reporting rates averaged 3.5/1000 VLBW infants (n = 205) and 1.1/1000 infants >1500 g (n = 128). Among all 333 infants with CMV, 314 (94%) were discharged home alive, 271 (86%) were referred for HRIF and 205 (65%) had ≥1 visit. Whereas infants born to mothers <20 years of age had highest CMV reporting rates and those born to Hispanic mothers comprised 49% of all infected infants, they had the highest loss of follow-up. At the 12-month visit (n = 152), 19 (13%) infants with CMV had bilateral blindness and 18 (12%) had hearing loss. At the 24-month visit, 5 (5%) of 103 had severe cerebral palsy. CONCLUSIONS: Among infants admitted to the NICU, those with CMV diagnoses may over represent infants with more severe CMV disease and outcomes. The CPQCC and HRIF program findings may help inform implementation of surveillance for congenital CMV infection in other U.S. states and guide strategies to reduce disparities in access to services.

Evaluation of Ethiopia's field epidemiology training program - frontline: perspectives of implementing partners.

BACKGROUND: Field Epidemiology Training Program (FETP) has been adopted as an epidemiology and response capacity building strategy worldwide. FETP-Frontline was introduced in Ethiopia in 2017 as a three-month in-service training. In this study, we evaluated implementing partners' perspectives with the aim of understanding program effectiveness and identifying challenges and recommendations for improvement. METHODS: A qualitative cross-sectional design was utilized to evaluate Ethiopia's FETP-Frontline. Using a descriptive phenomenological approach, qualitative data were collected from FETP-Frontline implementing partners, including regional, zonal, and district health offices across Ethiopia. We collected data through in-person key informant interviews, using semi-structured questionnaires. Thematic analysis was conducted, assisted with MAXQDA, while ensuring interrater reliability by using the consistent application of theme categorization. The major themes that emerged were program effectiveness, knowledge and skills differences between trained and untrained officers, program challenges, and recommended actions for improvement. Ethical approval was obtained from the Ethiopian Public Health Institute. Informed written consent was obtained from all participants, and confidentiality of the data was maintained throughout. RESULTS: A total of 41 interviews were conducted with key informants from FETP-Frontline implementing partners. The regional and zonal level experts and mentors had a Master of Public Health (MPH), whereas district health managers were Bachelor of Science (BSc) holders. Majority of the respondents reflected a positive perception towards FETP-Frontline. Regional and zonal officers as well as mentors mentioned that there were observable performance differences between trained and untrained district surveillance officers. They also identified various challenges including lack of resources for transportation, budget constraints for field projects, inadequate mentorship, high staff turnover, limited number of staff at the district level, lack of continued support from stakeholders, and the need for refresher training for FETP-Frontline graduates. CONCLUSIONS: Implementing partners reflected a positive perception towards FETP-Frontline in Ethiopia. In addition to scaling-up the program to reach all districts to achieve the International Health Regulation 2005 goals, the program also needs to consider addressing immediate challenges, primarily lack of resources and poor mentorship. Continued monitoring of the program, refresher training, and career path development could improve retention of the trained workforce.

Adeno-associated virus type 2 in US children with acute severe hepatitis.

As of August 2022, clusters of acute severe hepatitis of unknown aetiology in children have been reported from 35 countries, including the USA1,2. Previous studies have found human adenoviruses (HAdVs) in the blood from patients in Europe and the USA3-7, although it is unclear whether this virus is causative. Here we used PCR testing, viral enrichment-based sequencing and agnostic metagenomic sequencing to analyse samples from 16 HAdV-positive cases from 1 October 2021 to 22 May 2022, in parallel with 113 controls. In blood from 14 cases, adeno-associated virus type 2 (AAV2) sequences were detected in 93% (13 of 14), compared to 4 (3.5%) of 113 controls (P < 0.001) and to 0 of 30 patients with hepatitis of defined aetiology (P < 0.001). In controls, HAdV type 41 was detected in blood from 9 (39.1%) of the 23 patients with acute gastroenteritis (without hepatitis), including 8 of 9 patients with positive stool HAdV testing, but co-infection with AAV2 was observed in only 3 (13.0%) of these 23 patients versus 93% of cases (P < 0.001). Co-infections by Epstein-Barr virus, human herpesvirus 6 and/or enterovirus A71 were also detected in 12 (85.7%) of 14 cases, with higher herpesvirus detection in cases versus controls (P < 0.001). Our findings suggest that the severity of the disease is related to co-infections involving AAV2 and one or more helper viruses.

Congenital cytomegalovirus surveillance in the United States.

BACKGROUND: Congenital cytomegalovirus (cCMV) is not a nationally notifiable condition, and little is known about how U.S. health departments (HDs) currently conduct cCMV surveillance. METHODS: We surveyed U.S. HDs that conduct cCMV surveillance or screening activities identified through a web-based assessment. Meetings were held with each HD to enhance our understanding of survey responses. RESULTS: Ten states are systematically collecting cCMV case data to track cCMV cases during early infancy and to provide resources and services to families. Cases are ascertained using cCMV diagnostic codes, reported diagnosis, or laboratory results. Data elements collected for each case include demographics (all 10 states), clinical signs (8 states), laboratory data (4 states), treatment (4 states), and long-term outcomes (1 state). Annual number of cases reported by HDs ranged from 3 to 47 cases/year in seven states, which was much lower than the expected number of cCMV cases. All 10 HDs have the ability to analyze data collected and four disseminate findings. Major challenges of surveillance reported by HDs were lack of standardized case definitions, personnel constraints, and limited funding. CONCLUSIONS: A comprehensive account of cCMV disease burden is severely limited by low case ascertainment and paucity of data on long-term outcomes. A standardized public health case definition for cCMV would improve consistency in measuring disease prevalence across jurisdictions and over time. Surveillance for cCMV has the potential to increase disease awareness and inform strategies to prevent cCMV-associated disabilities.

Rapid virtual training and field deployment for COVID-19 surveillance officers: experiences from Ethiopia.

Rapid scale-up of surveillance activities is the key to successful coronavirus disease 2019 (COVID-19) pandemic prevention and mitigation. Ethiopia did not have a sufficient number of active surveillance officers for the public health COVID-19 response. Training of surveillance officers was needed urgently to fill the gap in the workforce needed. Subject-matter experts from the United States and Ethiopia developed applicable training modules including background on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), contact investigation, and communications. The training modules were delivered live in real-time via web-based virtual presentation. Seventy-seven health surveillance officers were hired, trained, and deployed in two weeks to assist with surveillance activities in Ethiopia. Electronic capacity building is needed in order to improve Web-based training in resource-limited settings where internet access is limited or unreliable. Web-based synchronously delivered course was an effective platform for COVID-19 surveillance training. However, strengthening public and private information technology capacity, literacy, and internet availability will improve Web-based education platforms in resource-limited countries.

Incorporating COVID-19 into Acute Febrile Illness Surveillance Systems, Belize, Kenya, Ethiopia, Peru, and Liberia, 2020-2021.

Existing acute febrile illness (AFI) surveillance systems can be leveraged to identify and characterize emerging pathogens, such as SARS-CoV-2, which causes COVID-19. The US Centers for Disease Control and Prevention collaborated with ministries of health and implementing partners in Belize, Ethiopia, Kenya, Liberia, and Peru to adapt AFI surveillance systems to generate COVID-19 response information. Staff at sentinel sites collected epidemiologic data from persons meeting AFI criteria and specimens for SARS-CoV-2 testing. A total of 5,501 patients with AFI were enrolled during March 2020-October 2021; >69% underwent SARS-CoV-2 testing. Percentage positivity for SARS-CoV-2 ranged from 4% (87/2,151, Kenya) to 19% (22/115, Ethiopia). We show SARS-CoV-2 testing was successfully integrated into AFI surveillance in 5 low- to middle-income countries to detect COVID-19 within AFI care-seeking populations. AFI surveillance systems can be used to build capacity to detect and respond to both emerging and endemic infectious disease threats.

Wastewater Testing and Detection of Poliovirus Type 2 Genetically Linked to Virus Isolated from a Paralytic Polio Case - New York, March 9-October 11, 2022.

In July 2022, a case of paralytic poliomyelitis resulting from infection with vaccine-derived poliovirus (VDPV) type 2 (VDPV2)§ was confirmed in an unvaccinated adult resident of Rockland County, New York (1). As of August 10, 2022, poliovirus type 2 (PV2)¶ genetically linked to this VDPV2 had been detected in wastewater** in Rockland County and neighboring Orange County (1). This report describes the results of additional poliovirus testing of wastewater samples collected during March 9-October 11, 2022, and tested as of October 20, 2022, from 48 sewersheds (the community area served by a wastewater collection system) serving parts of Rockland County and 12 surrounding counties. Among 1,076 wastewater samples collected, 89 (8.3%) from 10 sewersheds tested positive for PV2. As part of a broad epidemiologic investigation, wastewater testing can provide information about where poliovirus might be circulating in a community in which a paralytic case has been identified; however, the most important public health actions for preventing paralytic poliomyelitis in the United States remain ongoing case detection through national acute flaccid myelitis (AFM) surveillance†† and improving vaccination coverage in undervaccinated communities. Although most persons in the United States are sufficiently immunized, unvaccinated or undervaccinated persons living or working in Kings, Orange, Queens, Rockland, or Sullivan counties, New York should complete the polio vaccination series as soon as possible.

Interim Analysis of Acute Hepatitis of Unknown Etiology in Children Aged <10 Years - United States, October 2021-June 2022.

On April 21, 2022, CDC issued a health advisory† encouraging U.S. clinicians to report all patients aged <10 years with hepatitis of unknown etiology to public health authorities, after identification of similar cases in both the United States (1) and Europe.§ A high proportion of initially reported patients had adenovirus detected in whole blood specimens, thus the health advisory encouraged clinicians to consider requesting adenovirus testing, preferentially on whole blood specimens. For patients meeting the criteria in the health advisory (patients under investigation [PUIs]), jurisdictional public health authorities abstracted medical charts and interviewed patient caregivers. As of June 15, 2022, a total of 296 PUIs with hepatitis onset on or after October 1, 2021, were reported from 42 U.S. jurisdictions. The median age of PUIs was 2 years, 2 months. Most PUIs were hospitalized (89.9%); 18 (6.1%) required a liver transplant, and 11 (3.7%) died. Adenovirus was detected in a respiratory, blood, or stool specimen of 100 (44.6%) of 224 patients.¶ Current or past infection with SARS-CoV-2 (the virus that causes COVID-19) was reported in 10 of 98 (10.2%) and 32 of 123 (26.0%) patients, respectively. No common exposures (e.g., travel, food, or toxicants) were identified. This nationwide investigation is ongoing. Further clinical data are needed to understand the cause of hepatitis in these patients and to assess the potential association with adenovirus.