Outbreak of COVID-19 among vaccinated and unvaccinated homeless shelter residents — Sonoma County, California, July 2021

In July 2021, the Sonoma County Health Department was alerted to three cases of COVID-19 among residents of a homeless shelter in Santa Rosa, California. Among 153 shelter residents, 83 (54%) were fully vaccinated; 71 (86%) vaccinated residents had received the Janssen COVID-19 vaccine and 12 (14%) received an mRNA (Pfizer BioNTech or Moderna) COVID-19 vaccine. Within 1 month, 116 shelter residents (76%) received positive SARS-CoV-2 test results, including 66 fully vaccinated residents and 50 not fully vaccinated. 9 fully vaccinated and 1 unvaccinated were hospitalized for COVID-19. All hospitalized cases had at least one underlying medical condition. Two deaths occurred, one in a vaccinated resident and one in a non-vaccinated resident. Specimens from 52 residents underwent whole genome sequencing; all were identified as SARS-CoV-2, Delta Variant AY.13 lineage. Additional mitigation measures are needed in medically vulnerable congregate setting where limited resources make individual quarantine and isolation not feasible.

Household quarantine of second degree contacts is an effective non-pharmaceutical intervention to prevent tertiary cases in the current SARS-CoV pandemic

Background Given the characteristics of SARS-CoV2 with regard to transmission before the onset of symptoms and varying manifestation indices according to age, isolation and quarantine have limited efficacy in the current pandemic. Household quarantine in second degree contacts (Hh-Q2°) outside the case household has so far only been addressed by modellers. In the literature there is no publication based on field data. Methods In a retrospective cohort study on real field data from a county health department (CHD), all PCR-confirmed cases and related contact persons put into quarantine were analysed. Hh-Q2° was used in our CHD from the onset of the pandemic. Results From 9 March to 8 December 2020, 353 PCR-confirmed cases were registered in the CHD Ploen, Northern Germany: 225 (63.7%) primary, 107 (30.3%) secondary and 21 (5.9%) tertiary cases. The 107 secondary cases resulted out of 470 (22.8%) close or 1°contacts and 21 tertiary cases out of 179 (11.7%) indirect or 2°contacts put into quarantine. The efficacy of Hh-Q2° was 51.5% (11.7%/22.8%) of that of quarantine in 1°contacts; 16.4% of all converted cases in quarantined persons were ascertained by Hh-Q2°. One in ten 1°contacts in households with tertiary cases remained asymptomatic. Conclusion The impact of Hh-Q2° in preventing further spread of SARS-CoV2 was considerable. With half the conversion rate in 2°contacts compared to 1°contacts, the efficacy of Hh-Q2° is substantial. Hh-Q2° should definitely be used routinely to control the spread of SARS-CoV2 more efficiently and national authorities should include it in their guidelines.

Improving Care for Individuals Living With Intellectual Developmental Disabilities and Dementia

Ultimately, transformation of communities can only occur through educational efforts delivered to specific community sectors. Although the portion of people with Intellectual Developmental Disabilities who develop dementia as they age is equal to that of the general population, individuals with Down syndrome are at a much higher risk. This symposium will describe how a county health department partnered with the local County Board of Developmental Disabilities to systematically incorporate Dementia Friends for Intellectual Developmental Disabilities with Alzheimer’s disease training to their staff and provider network. We will describe who to get on board with the idea, how to organize, and how to deliver specific trainings. Outcomes related to increase in participant knowledge, increases in service provision and outcomes related to staff mentoring will be discussed.

Household quarantine of second degree contacts is an effective non-pharmaceutical intervention to prevent tertiary cases in the current SARS-CoV pandemic

Background Given the characteristics of SARS-CoV2 with regard to transmission before the onset of symptoms and varying manifestation indices according to age, isolation and quarantine have limited efficacy in the current pandemic. Household quarantine in second degree contacts (Hh-Q2°) outside the case household has so far only been addressed by modellers. In the literature there is no publication based on field data. Methods In a retrospective cohort study on real field data from a county health department (CHD), all PCR-confirmed cases and related contact persons put into quarantine were analysed. Hh-Q2° was used in our CHD from the onset of the pandemic. Results From 9 March to 8 December 2020, 353 PCR-confirmed cases were registered in the CHD Ploen, Northern Germany: 225 (63.7%) primary, 107 (30.3%) secondary and 21 (5.9%) tertiary cases. The 107 secondary cases resulted out of 470 (22.8%) close or 1°contacts and 21 tertiary cases out of 179 (11.7%) indirect or 2°contacts put into quarantine. The efficacy of Hh-Q2° was 51.5% (11.7%/22.8%) of that of quarantine in 1°contacts; 16.4% of all converted cases in quarantined persons were ascertained by Hh-Q2°. One in ten 1°contacts in households with tertiary cases remained asymptomatic. Conclusion The impact of Hh-Q2° in preventing further spread of SARS-CoV2 was considerable. With 51% of the conversion rate in 2°contacts compared to 1°contacts, the efficacy of Hh-Q2° is substantial. Hh-Q2° should definitely be used routinely to control the spread of SARS-CoV2 more efficiently and national authorities should include it in their guidelines.

Household Quarantine of Second Degree Contacts Is an Effective Non- Pharmaceutical Intervention to Prevent Tertiary Cases in the Current Pandemic

Background: Given the characteristics of SARS-CoV2 in regard to transmission before the onset of symptoms and varying manifestation indices according to age, isolation and quarantine have limited efficacy in the current pandemic. Household quarantine in second degree contacts (Hh-Q2°) outside the case household was so far only addressed by modellers. There is no publication based on field data in the literature.Methods: In a retrospective cohort study on real field data from a county health department (CHD), all PCR-confirmed cases and related contact persons put into quarantine were analysed. Hh-Q2° was used in our CHD from the beginning of the pandemic.Results: From 9 March to 8 December 2020, 353 PCR-confirmed cases were registered in the CHD Ploen, Northern Germany: 225 (63.7%) primary, 107 (30.3%) secondary and 21 (5.9%) tertiary cases. The 107 secondary cases resulted out of 470 (22.8%) close or 1°contacts and 21 tertiary cases out of 179 (11.7%) indirect or 2°contacts put into quarantine. The efficacy of Hh-Q2° was 51.5% (11.7%/22.8%) of the efficacy of quarantine in 1°contacts; 16.4% of all converted cases in quarantined persons were ascertained by Hh-Q2°. One in ten 1°contacts in households with tertiary cases remained asymptomatic.Conclusion: The impact of Hh-Q2° in preventing further spread of SARS-CoV2 was considerable. With half the conversion rate in 2°contacts in comparison to 1°contacts, the efficacy of Hh-Q2° is substantial. Hh-Q2° should urgently be used routinely to control the spread of SARS-CoV2 more efficiently and national authorities should include it in their guidelines.

1653. Strong Partnership and Effective Communication Between a Tertiary Hospital and a County Health Department Were Critical in Controlling a 2019 Measles Outbreak in Southeast Michigan (SEM)

Background Measles, declared eliminated in the US 2000, is a reemerging vaccine-preventable airborne disease. The 2019 case count (704 as of April 30, 2019) has surpassed the number of 2014 cases (667), the highest since 1994. Many healthcare personnel (HCP) have not seen a case of measles, and this lack of clinical experience may contribute to missed or delayed diagnoses leading to its spread. We describe the processes and measures implemented at Beaumont Hospital, Royal Oak (B-RO) Michigan in collaboration with the Oakland County Health Department (OCHD) to prevent secondary spread during an outbreak. Methods Soon after the initial report of the index case in Oakland County in March, the B-RO epidemiology team connected with OCHD. As both exposed and suspected cases were expected to seek care at B-RO, a one-page informational document was sent to B-RO providers. This document detailed isolation precautions and testing methods, post-exposure prophylaxis (PEP), and contact information. During subsequent days, as measles cases increased, frequent calls between B-RO and OCHD addressed numerous issues, including: media notifications, contact of exposed persons, vaccine and immunoglobulin supply for PEP, safe referral of cases to the EC, and the process of measles specimen submission for testing. As needed, these communications occurred after business hours and during weekends. Serologic testing to confirm measles immunity was ramped up. Results As of April 30, 41 cases have been confirmed in MI associated with the index case. OCHD facilitated the exposure control for 40 patients, of which 6 came to B-RO during their infectious period (Figure 1). To date, there have been no secondary cases developing in B-RO patients, HCPs or visitors, which may be related to successful engineering controls, appropriate protective equipment, mandatory measles immunity confirmation as condition of Beaumont employment since the late 1980s, institution of furlough procedures, PEP for hospitalized patients, and widespread communications with patients, visitors and HCPs (Figure 2). Conclusion During an outbreak, close healthcare facility and local health department collaboration is essential in rapidly limiting an airborne disease outbreak. Disclosures All authors: No reported disclosures.