In August 2023, 68% (n=25,900) of the Northwest Territories, Canada, evacuated from wildfires, including the never previously evacuated capital, Yellowknife. Official evacuation orders extended from August 16 to September 6 for this region, impacting health protection services (HPS) in the Territory for remaining residents, and risks on return.

The Office of the Chief Public Health Officer (OCPHO) reviewed and implemented priorities over a three-day period prior to the evacuation order for time critical HPS to continue remotely or transfer to receiving jurisdictions. On return to community, OCPHO implemented processes for reviewing surveillance objectives to assess for impacts to affected populations.

During evacuation, over 15 reports of animal exposures were assessed remotely for rabies prophylaxis. Individuals requiring sexually transmitted infection (STI) follow-up were referred to receiving jurisdictions. One patient with infectious tuberculosis was transferred to another province. Water plant operators were supported with new communication and out-of-Territory testing protocols. On return, enhanced surveillance included: respiratory viruses, STI and blood borne infections, gastrointestinal illness, and toxic drug supplies.

While some HPS continued to mitigate risks, future surveillance will assess the scale of impacts. Updates to continuity of operations plans need to include considerations for remote and local services.

Performance characteristics of SARS-CoV-2 nucleic acid detection assays are understudied within contexts of low pre-test probability, including screening asymptomatic persons without epidemiological links to confirmed cases, or asymptomatic surveillance testing. SARS-CoV-2 detection without symptoms may represent presymptomatic or asymptomatic infection, resolved infection with persistent RNA shedding, or a false-positive test. This study assessed the positive predictive value of SARS-CoV-2 real-time reverse transcription polymerase chain reaction (rRT-PCR) assays by retesting positive specimens from 5 pre-test probability groups ranging from high to low with an alternate assay.

In total, 122 rRT-PCR positive specimens collected from unique patients between March and July 2020 were retested using a laboratory-developed nested RT-PCR assay targeting the RNA-dependent RNA polymerase (RdRp) gene followed by Sanger sequencing.

Significantly fewer (15.6%) positive results in the lowest pre-test probability group (facilities with institution-wide screening having ≤3 positive asymptomatic cases) were reproduced with the nested RdRp gene RT-PCR assay than in each of the 4 groups with higher pre-test probability (individual group range, 50.0%–85.0%).

Large-scale SARS-CoV-2 screening testing initiatives among low pre-test probability populations should be evaluated thoroughly prior to implementation given the risk of false-positive results and consequent potential for harm at the individual and population level.

Approximately 1.2 million persons in Oakland County, Michigan (USA) reside less than 50 miles from the Fermi Nuclear Power Plant, Unit 2, but information is limited regarding how residents might react during a radiation emergency. Community Assessment for Public Health Emergency Response (CASPER) survey methodology has been used in disaster and nondisaster settings to collect reliable and accurate population-based public health information, but it has not been used to assess household-level emergency preparedness for a radiation emergency. To improve emergency preparedness plans in Oakland County, including how residents might respond during a radiation emergency, Oakland County Health Division (OCHD), with assistance from the Centers for Disease Control and Prevention (CDC) and the Michigan Department of Community Health (MDCH), conducted a CASPER survey.

During September 2012, a 2-stage cluster sampling design was used to select 210 representative households in Oakland County. By using in-person surveys, the proportion of households with essential needs and supplies, how residents might respond to public health authorities’ instructions, and their main source for obtaining information during a radiation emergency were assessed. Data were weighted to account for the complex sampling design.

Of the goal of 210 households, 192 (91.4%) surveys were completed: 64.7% and 85.4% of respondents indicated having 3-day supplies of water and of nonperishable food, respectively; 62.8% had a 7-day supply of prescription medication for each person who needed it. Additionally, 64.2% had a working carbon monoxide detector; 67.1% had a first-aid kit; and 52% had an alternative heat source. In response to instructions from public health officials during a radiation emergency, 93.3% of all respondents would report to a radiation screening center; 96% would evacuate; and 91.8% would shelter-in-place. During a radiation emergency, 55.8% of respondents indicated their main information source would be television, 18.4% radio, and 13.6% the Internet. The most trusted source for information would be the local public health department (36.5%), local news (23%), a physician (11.2%), and family members (11.1%). Including completed and incomplete interviews, refusals, and nonrespondents, 517 total households were contacted.

CASPER data regarding how residents might react during a radiation emergency provided objective and quantifiable information that will be used to develop Oakland County's radiation emergency preparedness plans. Survey information demonstrates the feasibility and usefulness of CASPER methodology for radiation emergency preparedness planning.

NyakuMK, WolkinAF, McFaddenJ, CollinsJ, MurtiM, SchnallA, BiesS, StanburyM, BeggsJ, BayleyegnTM. Assessing Radiation Emergency Preparedness Planning by Using Community Assessment for Public Health Emergency Response (CASPER) Methodology. Prehosp Disaster Med. 2014;29(3):1-9.

We examined the association between housing type and household emergency preparedness among households in Oakland County, Michigan.

We used interview data on household emergency preparedness from a cluster design survey in Oakland County, Michigan, in 2012. We compared survey-weighted frequencies of household demographics, medical conditions, and preparedness measures in single-detached homes versus multi-unit dwellings, and determined the unadjusted odds ratios (OR) and the income-level adjusted OR for each preparedness measure.

Households had similar demographics and medical conditions between housing types. Unadjusted ORs were statistically significant for single detached homes having a generator (11.1), back-up heat source (10.9), way to cook without utilities (5.8), carbon monoxide (CO) detector (3.8), copies of important documents (3.4), evacuation routes (3.1), and 3-day supply of water (2.5). Income level adjusted ORs remained statistically significant except for owning a CO detector.

Households in multi-unit dwellings were less likely to have certain recommended emergency plans and supplies compared to those in single detached homes. Further research is required to explore the feasibility, barriers, and alternatives for households in multi-unit dwellings in terms of complying with these measures. (Disaster Med Public Preparedness. 2014;0:1–8)