bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-1272. Hepatitis A Investigation and Onsite Response in a Retirement Facility, New York City, 2023
Authors: Badenhop Brittan P , Waechter HaeNa , McElroy Roisin , Latash Julia , Gu-Templin Tingting , Chen Judy , Antwi Mike O , Stavinsky Faina , Barnes Rameez , Crouch Bindy , McPherson Tristan D 
Published: January 2025

Abstract

Background
Hepatitis A is a contagious liver infection that can be transmitted by contaminated food consumption. On August 13, 2023, a healthcare provider notified the New York City Health Department of a hepatitis A case in a food handler who worked at a retirement facility while infectious. Medical frailty, mobility, and transportation limitations complicated exposed persons’ access to postexposure prophylaxis (PEP) within the recommended 2-week window. During the COVID-19 pandemic, the Health Department developed capacity to provide onsite SARS-CoV-2 testing and vaccination services within congregate settings to prevent and respond to outbreaks. We used this infrastructure to deliver timely PEP to contacts and prevent an outbreak.

Methods
Using a risk-assessment algorithm, we evaluated the food handler’s hand hygiene, type and quantity of food prepared, and contact with ready-to-eat food. Anyone who ate food the worker prepared while infectious, defined as 2 weeks before symptom onset, was considered exposed. Following Advisory Committee on Immunization Practices guidance, 1 dose of single-antigen hepatitis A vaccine was advised for exposed adults, with coadministration of 0.1 mL/kg human immunoglobulin (IG) for those age &gt; 40 years. Food handlers were required to receive PEP to prevent workplace exclusion. To enable timely PEP receipt, the Health Department worked with facility staff and a vendor to host an onsite clinic on August 23, 2023.

Results
We identified 84 exposed persons, including 42 (50%) residents, 10 (12%) food handlers, and 32 (38%) staff. Median age of those exposed was 74 years (interquartile range [IQR]: 58–88 years); residents’ median age was 89 years (IQR: 84–91 years). Of 84 exposed persons, 39 (46%) received PEP; 30 (77%) received vaccine and IG, 1 (3%) IG only, and 8 (21%) vaccine only. Seven exposed persons who received only vaccine were eligible for IG. All 10 (100%) exposed food handlers, 18 (43%) residents, and 11 (34%) staff received PEP. One secondary case was identified in a resident who declined PEP.

Conclusion
This intervention ensured residents were protected and prevented work exclusions. Providing timely, accessible clinical services within congregate settings, as was commonly done for COVID-19, might effectively prevent the spread of other infections.

Disclosures
All Authors: No reported disclosures
P-1276. Infant Treatment for Congenital Syphilis Among Syphilis-Impacted Pregnancies
Authors: Sancken Christina L , Carlson Jeffrey , Schubert Sara L , O’Callaghan Kevin P , Fountain Alison , Woodworth Kate Russell 
Published: January 2025

Abstract

Background
Congenital syphilis (CS) has been rising in the U.S. since 2013 and is a significant public health challenge1. The Sexually Transmitted Infections (STI) Treatment Guidelines provide treatment recommendations for four different clinical scenarios based on adequacy of treatment during pregnancy, laboratory testing of both the infant and birth parent, and clinical signs2. We used data from the Surveillance for Emerging Threats to Pregnant People and Infants Network3 from five U.S. state and local health departments to describe patterns of treatment among infants born to people with syphilis during pregnancy (Figure 1).

Methods
Infants were classified based on modified STI Treatment Guidelines clinical scenarios2, and included three of the four clinical scenarios: confirmed/highly probable CS, possible CS, and CS less likely. We describe the frequency of prenatal and neonatal characteristics among those who did and did not receive treatment as recommended by the STI Treatment Guidelines (Figure 2).

Results
Of the 1368 liveborn infants with complete medical record abstraction, 13% were classified as confirmed/highly probable CS, 33% as possible CS, and 54% as CS less likely (Figure 3). Frequency of receiving the standard of care was 65% for confirmed/highly probable, 76% for possible, and 34% for CS less likely. The frequency of no reported treatment was 16% for confirmed/highly probable CS, 20% for possible CS, and 45% for CS less likely. The frequency of no reported treatment among confirmed/highly probable CS was highest among infants born to people who were Black non-Hispanic, though numbers were small. Of infants with CS less likely, 18% received more than the recommended one dose (Table).

Conclusion
This report highlights opportunities for improvement in care of infants exposed to syphilis, including racial disparities in recommended care4, that require multipronged approaches to address. Provider education and strong partnerships with well-resourced public health systems can improve coordination of care to ensure infants receive the standard of care. Efforts to improve care of syphilis exposed infants must include efforts to better address larger issues of systematic racism and historical injustices in healthcare and public health to improve equity.Table.Cohort Characteristics by Clinical Scenario and Infant Treatment Status

Disclosures
All Authors: No reported disclosures
P-1288. Changes in Social Contact Patterns Concerning the Respiratory Illness: A Chronological Study in Japan
Authors: Jeong Hwichang , Park Sehyun , Chun June Young , Kim Yongdai , Tsuzuki Shinya 
Published: January 2025

Abstract

Background
Transmission dynamics of respiratory pathogens are largely dependent on social mixing patterns, Besides, individuals who are ill might change their contact behavior according to their symptoms. However, there is a paucity of data on social mixing patterns concerning the respiratory illness.

Methods
Here, we conducted an internet-based periodic survey in Japan since 2022 to characterize the differences in mixing patterns during and after the illness. First, participants who had the respiratory illness were recruited and followed up 2 weeks later.
Contact matrices consisting of the age-specific average number of contacted persons recorded per day were obtained from the survey data, using the bootstrap method. Reciprocity was achieved by using the weighted averages according to the age-specific population sizes [1].

Results
Contact patterns were generally age-assortative, and the average contact numbers had gradually increased from March 2022 to August 2023. Most recently, the median number of contacts per day during respiratory illness was 3 (interquantile range [IQR] = 1-7) and then rose to 5 (IQR = 3-12) in August 2023. The increase ratio was 1.7 (IQR = 0.1-2.3). The baseline frequency of social contacts during illness was identical to the numbers studied in 2021 in Japan (median number of contacts = 3 [IQR = 1-6]) [2]. The number of contacts increased after illness but considering the contact frequency in the 2011 study (median number of contacts = 12), it has not yet reached the pre-COVD-19 status [3].Figure 1.Contact matrices during and after illness within the study period.

Conclusion
In this study, we found that individuals tend to decrease their contacts by up to 50% when they feel unwell. This gap was not found until March 2022 in Japan when social distancing measures against COVID-19 remain. Afterward, the frequency of social contact tends to rise but has not yet reached the pre-COVID-19 era as of August 2023.

Disclosures
All Authors: No reported disclosures
P-1295. Meningococcal Disease in Children in Argentina: A 4-year Active Sentinel Hospital Surveillance Study during the Post-Meningococcal Vaccination Era: A Difficult Impact Analysis
Authors: Gentile Angela , Bakir Julia , Maydana Mara N , Morales Juan C , Ensinck Gabriela , Ernst Adriana , Melonari Pablo A , Cardozo Ana C , Iturres Alejandro Santillan , Santos Mauricio , Efron Adriana 
Published: January 2025

Abstract

Background
In 2017, MenACWY-CRM197 vaccine was introduced in the national immunization program (NIP) in Argentina (2+1 schedule, +1 dose at 11 years). In the pre-vaccination period (preVp, 2012-2015), the meningococcal disease (MD) burden had been assessed.
The objectives of this study were: to evaluate the impact of the intervention on the burden of MD in ≤15 years during a post-vaccination period (postVp, January 2020 to December 2023) and to describe the clinical-epidemiological-bacteriological pattern of all confirmed MD cases of postVp versus preVp.

Methods
Active hospital surveillance in 6 pediatric sentinel units in Argentina. MD discharge rates per 10,000 hospital discharges between preVp and postVp was compared.

Results
In postVp, of 186,257 hospitalized patients, 1047 (0.6 %) had suspected meningitis or MD, of which 9.1 % (95/1047) had acute bacterial meningitis (ABM) and 1.1 % (11/1047) meningococcemia; 79 % (75/95) of ABM cases were confirmed by culture, corresponding 8.0 % (6/75) to Neisseria meningitidis (Nm). In addition, in 2 out of 11 meningococcemia cases a Nm was confirmed by culture. 41.4 % (12/29) of MD culture-negative cases were confirmed by PCR. Thus, there were a total of 20 MD cases, a discharge rate of 1.1 (0.7-1.7) and a reduction of 78.9 % compared to the preVp. Of the 20 MD cases in the postVp, median age was 38 months (IQR 26-95), 13 had MenACWY-CRM197. Microbiological/molecular diagnosis was made in blood/serum (9; 40.9 %) and CSF (13; 59.1 %). Capsular group was identified in 14 samples (B:13; C:1).

Conclusion
After the MenACWY-CRM197 vaccine introduction in the NIP, the burden of MD in ≤15 years was reduced almost 80%. The predominant serogroup was B.
These findings could be interpreted as an effect of the vaccine, but it is necessary to also take into account the biases inherent in vaccine impact studies (COVID-19 pandemic, lockdown measures, natural fluctuations in the incidence of MD, among others).

Disclosures
All Authors: No reported disclosures
P-1296. Community-acquired methicillin-resistant Staphylococcus aureus infections: 1 year of surveillance in 6 pediatric centers
Authors: Gentile Angela , Bakir Julia , Firpo Maria Veronica , Juarez Ximena S , Cancellara Aldo , Tapponnier Gabriela , Tinnirello Agostina , Lopez Oscar , Lopez Leandro , Pejito Maria Natalia , Papucci Santiago Lopez , Ensinck Gabriela 
Published: January 2025

Abstract

Background
Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections is emerging in the world and can have a serious evolution. The objective of this study were to study the hospitalization rate, the clinical-epidemiological and bacteriological pattern and the case fatality risk factors of CA-MRSA infection.

Methods
Cross-sectional observational epidemiological study, with prospective data capture. All patients ≤ 15 years of age with community-acquired Staphylococcus aureus (CA-SA) infection hospitalized in 6 pediatric sentinel units, between January and December 2023, were included. The rate of CA-MRSA cases per 10,000 hospital discharges was calculated. with 95 % confidence interval (95 % CI).

Results
Of a total of 201 patients with CA-SA infection, 131 (65.2 %) were CA-MRSA. The global hospitalization rate for CA-MRSA cases was 27.8 (23.3-32.9), with a higher rate in &lt; 2 years 37,7 (27,9-49,8). Of the 131 cases: 56.5 % were male, median age 48.8 months (IQR 16.4-90.4), ≥ 2 years 64.9%, complete vaccination card 77.0 %, low socioeconomic level 54.2 %, overcrowding 15.3 %, underlying disease 29.0 %, passive smoking 24.4 %. The clinical presentations were (n; %): skin and soft tissue infection (SSTI 101; 77.1 %), arthritis (17; 13.0 %), osteomyelitis (12; 9.2 %), pneumonia (16; 12.2 %; 14 with pleural effusion and 3 necrotizing), sepsis (11; 8.4 %), bacteremia (4; 3.1 %), meningitis (1; 0.8 %). Conventional microbiological diagnosis was performed in 130 cases and molecular diagnosis in one. 4 cases had coinfection with group A beta hemolytic Streptococcus. Antibiotic resistance was for erythromycin 43.1 %, clindamycin 26.0 %, gentamicin 19.9 %, TMP-SMX 1.5 %. All strains were susceptible to vancomycin. Fatality rate: 1.5 % (2/131). No deceased case had an underlying disease. 18.2 % (2/11) of sepsis cases died (2-tailed Fisher exact p 0.006), however, there was no significant association in the multivariate analysis.

Conclusion
The high burden of CA-MRSA infection, the most common clinical form of SSTI, and the high profile of antibiotic resistance, highlight the importance of continuous clinical surveillance and alert for these infections.

Disclosures
All Authors: No reported disclosures
P-1306. Establishing Respiratory Syncytial Virus (RSV) Surveillance Methodology within the Indian Health Service
Authors: Desai Keya , Apostolou Andria , Houghton Sarah , Chukwuma Uzo 
Published: January 2025

Abstract

Background
American Indian and Alaska Native (AI/AN) populations have high rates of Respiratory Syncytial Virus (RSV)-associated hospitalizations among both infants and older populations. Due to underrepresentation, most national surveillance reports do not adequately describe the burden of disease in the AI/AN population. Currently, there is no standardized approach for RSV surveillance within the IHS. This work explores establishing RSV surveillance using IHS-specific electronic medical records (EMR) data. Additionally, this work aims to implement a standardized surveillance methodology across IHS for RSV and adaptable for other infectious diseases. The objective of this abstract is to describe the process of RSV surveillance methodology within the IHS.
Venn diagram of ICD and LOINC datasets
The above image is a representation of the Venn diagram of ICD and LOINC datasets. The two datasets are merged together to identify the overlapped records and unique ICD and LOINC records for RSV.

Methods
We investigated the utility of using administrative data from Federal, Tribal, and Urban Indian health facilities for RSV surveillance among AI/AN population for Fiscal Year (FY) 2023. We evaluated RSV administrative codes, such as Logical Observation Identifiers Names and Codes (LOINC), International Classification of Diseases (ICD) 9 and 10, to develop an algorithm for RSV records. The records that contained either an ICD 9 or ICD 10 code for RSV came from the ICD dataset; records that contained RSV-specific LOINC code came from the LOINC dataset. Final set of records were flagged as positive and negative RSV records.Table 1.Distribution of unique LOINC records by the type of tests
The table shows the distribution of the unique LOINC records by the four categories of type of tests. The categories include PCR, Antigen, Antibody and Culture tests.

Results
In FY 2023, 16396 records came from the ICD dataset and 151542 records came from the LOINC dataset. On merging ICD and LOINC datasets, 4623 records overlapped, 11830 records were unique to ICD dataset and 146959 records were unique to LOINC dataset. Of the records unique to LOINC dataset (146959), 81% (n=119698) represent PCR tests while antigen (n=13722) and antibody (n=13384) tests represent 9% respectively.

Conclusion
This study highlights the importance of using both ICD and LOINC codes for identifying RSV cases in EMR. It aids in understanding trends and burden among AI/AN population. Currently, we are conducting site validations to evaluate the surveillance methods across IHS. Additionally, surveillance reports and epidemiological studies generated using this standard approach could help target interventions for RSV and other infectious diseases.

Disclosures
All Authors: No reported disclosures
P-1307. AI-Optimized Assessment of Vaccination Strategies in Smallpox Reemergence: an LA Case Study
Authors: Learoyd Tristan , Pittman John E 
Published: January 2025

Abstract

Background
The resilience of Los Angeles (LA) to smallpox was evaluated using a modified Susceptible, Exposed, Infectious, Recovered, Hospitalized, Deceased (SEIRHD) model, which simulated its spread via an artificial intelligence (AI) mobility matrix and assessed different vaccination regimens (one dose primary series vs a two dose primary series) for outbreak control.

Methods
The matrix combined data from travel surveys, transportation authorities, GPS caches, and population density estimates from LA County. Fifteen LA government districts plus a 30-mile radius city limit were considered for differential force of infection and mobility matrix variables. Transmission parameters, derived from a review of 20th-century epidemics, assigned 90% transmission to households and 80% to workplaces. Residual immunity against smallpox was set at 8.8%. Intensive care unit (ICU) capacity within 30 miles of LA city limits was set as 2,500 beds per the California Health and Human Services Open Data Portal. One and two dose ring vaccine regimens initiated at day 7 were assessed in 16 districts and as a dispersed city model to understand zonal resilience in eradication and if contagion exceeded ICU capacity limits via an R-programed scenario.

Results
The naïve general scenario had an infection peak at day 73, with a hospitalization peak of 5,600,227 (day 80) of a susceptible population of 18,833,640. With a 50% effective one dose vaccine, contagion remained below the ICU threshold in the basic 30-mile radius model. However, in specific districts (1, 6-9, and 13-15), even a 95% effective one dose vaccine couldn’t maintain contagion below the ICU threshold according to the AI-assisted zonal model. Hypothetical one dose primary series vaccination regimens outperformed two dose regimens in both city-wide and zonal scenarios (P&lt; 0.05). Zonal analysis based on housing conditions and mobility revealed that even with the most effective hypothetical one dose vaccine (95% efficacy after 7 days), 7 out of 15 LA district ICU thresholds were exceeded, indicating the importance of geospatial modelling.

Conclusion
The model highlights the importance of zone-based evaluations in preparedness and the need for high-efficacy single-dose vaccinations in ring vaccination.

Disclosures
Tristan Learoyd, MPharm MA MSc MBA PhD MRPharmS, Emergent: Employee John E. Pittman, PharmD, Emergent: Employee
P-1308. Survey of U.S. Hunters: Behaviors that May Increase Exposure to Chronic Wasting Disease
Authors: Boney Colton P , Lindenmuth Connor R , Trapp Nicholas J , Milbert Kevin J , Moore Tony L , Parker Robert W 
Published: January 2025

Abstract

Background
Chronic Wasting Disease (CWD) is caused by a prion leading to transmissible spongiform encephalopathy primarily in members of the Cervidae family such as deer, elk, and moose. At this time, there is insufficient data to suggest possible zoonosis. Although there have been no recorded cases of CWD in humans, studies have shown that squirrel monkeys (Saimiri sciureus) are susceptible to transmission of CWD in a laboratory setting. The goal of this survey was to collect and examine data about safe handling practices, awareness of CWD, testing use, and meat consumption among United States hunters.

Methods
The survey included questions regarding basic demographics, butchering, taxidermy, awareness of CWD, testing frequency/behaviors, and barriers to testing. Participants were recruited through state organizations as well as hunting/outdoors-associated social media pages. Hunters of deer, elk, or moose were invited to participate in the study if they had harvested one of those game species in the past five years. States were grouped in accordance with CDC-described regions to compare for statistical trends among the data.

Results
125 individuals participated in the survey. The majority consumed meat from all (82%) or most (9.6%) of their game. Respondents commonly tested none (67%) or some (20%) of the meat they consumed. Though 33.1% tested their harvest for CWD, 58% of those who tested did not wait for CWD test results before consuming the meat. In addition to meat consumption, 66% used meat processing plants, 86% participated in field dressing, and 41% taxidermized their animals at home. Barriers to testing included the belief that CWD was not in their respective area (44%) or that they did not have access to testing equipment and/or other resources (39%).

Conclusion
The survey highlighted that hunters who frequently consume meat from members of the Cervidae family in states with CWD are not frequently testing due to poor accessibility and lack of data monitoring endemic spread. This may lead to increased exposure risk for those unaware of the illness or believe that CWD is not in their game populations. More data is needed to understand the full extent of exposure risk as transmission risk of CWD to humans is further researched.

Disclosures
All Authors: No reported disclosures
P-1312. MPox Seroprevalence and Seroincidence among People who Inject Drugs in the Mexico-U.S. Border Region
Authors: Rimoin Anne , Halbrook Megan , Artamanova Irina , Panayampalli Subbian Satheshkumar , Townsend Michael , Priyamvada Lalita , Carson Will , Abramovitz Daniela , Chaillon Antoine , Smith David , Harvey-Vera Alicia , Vera Carlos F , Skaathun Britt , Strathdee Steffanie , Das Nabojeet , Rangel Gudelia 
Published: January 2025

Abstract

Background
We assessed seroprevalence and seroincidence against orthopoxvirus (OPXV) among people who inject drugs (PWID) in the U.S./Mexico border region during the COVID-19 pandemic.

Methods
Between 09/21-11/23, PWID who lived in either San Diego (SD; N=129) or Tijuana (TJ; N=343) underwent a baseline and follow-up visit involving interviewer-administered surveys and venipuncture. Sera were batch tested at the U.S. Center for Disease Control and Prevention using an OPXV generic IgG ELISA using JYNNEOS® vaccine as the viral antigen. Optical densities (OD) ≥0.1 were conservatively considered seropositive. Mpox seroprevalence was assessed after excluding known sources of anti-OPXV antibodies

Results
Of 472 participants enrolled, median age was 45 (IQR:38-53), 72.9% were male (3.2% of whom reported sex with men), 11.3% had HIV and 25.8% were unhoused. Although no symptoms consistent with Mpox were reported during the study, 50 (10.6%) had seropositive results at baseline, follow-up or both. Baseline OPXV seroprevalence was 19.4% in SD and 3.2% in TJ, and Mpox seroincidence was 8.97 (95%CI:4.09-13.85) per 100 person-years in TJ vs. 1.81 (95%CI: 0.00-5.35) in SD, with a median of 5.8 months of follow-up (IQR: 4.53 – 6.31 months). Excluding participants who reported Mpox vaccination (N=3), smallpox vaccination (N=73), or those born prior to 1971 who could have received smallpox vaccination (N=140), likely Mpox seroprevalence was 7.8% (23/296), with 13/23 seronegative at baseline but seropositive at follow-up. Of these 13 seroconveters, 5 were female of whom 2 were HIV+.

Conclusion
These preliminary data suggest a undetected Mpox circulation in the Mexico-U.S. border region between 2022 and 2023 and that asymptomatic or mildly symptomatic Mpox infection may be more common than previously recognized. Although the clinical implications of these findings remain unclear, expansion of Mpox vaccination to PWID may be warranted.

Disclosures
David Smith, MD, MAS, Bayer: Advisor/Consultant|Gilead: Advisor/Consultant|Model Medicines: Advisor/Consultant|Red Queen Therapuetics: Advisor/Consultant