Update: Interim Guidance for Health Care Providers Caring for Pregnant Women with Possible Zika Virus Exposure - United States (Including U.S. Territories), July 2017.

CDC has updated the interim guidance for U.S. health care providers caring for pregnant women with possible Zika virus exposure in response to 1) declining prevalence of Zika virus disease in the World Health Organization's Region of the Americas (Americas) and 2) emerging evidence indicating prolonged detection of Zika virus immunoglobulin M (IgM) antibodies. Zika virus cases were first reported in the Americas during 2015-2016; however, the incidence of Zika virus disease has since declined. As the prevalence of Zika virus disease declines, the likelihood of false-positive test results increases. In addition, emerging epidemiologic and laboratory data indicate that, as is the case with other flaviviruses, Zika virus IgM antibodies can persist beyond 12 weeks after infection. Therefore, IgM test results cannot always reliably distinguish between an infection that occurred during the current pregnancy and one that occurred before the current pregnancy, particularly for women with possible Zika virus exposure before the current pregnancy. These limitations should be considered when counseling pregnant women about the risks and benefits of testing for Zika virus infection during pregnancy. This updated guidance emphasizes a shared decision-making model for testing and screening pregnant women, one in which patients and providers work together to make decisions about testing and care plans based on patient preferences and values, clinical judgment, and a balanced assessment of risks and expected outcomes.

Travel history among persons infected with SARS-CoV-2 variants of concern in the United States, December 2020-February 2021.

The first three SARS-CoV-2 phylogenetic lineages classified as variants of concern (VOCs) in the United States (U.S.) from December 15, 2020 to February 28, 2021, Alpha (B.1.1.7), Beta (B.1.351), and Gamma (P.1) lineages, were initially detected internationally. This investigation examined available travel history of coronavirus disease 2019 (COVID-19) cases reported in the U.S. in whom laboratory testing showed one of these initial VOCs. Travel history, demographics, and health outcomes for a convenience sample of persons infected with a SARS-CoV-2 VOC from December 15, 2020 through February 28, 2021 were provided by 35 state and city health departments, and proportion reporting travel was calculated. Of 1,761 confirmed VOC cases analyzed, 1,368 had available data on travel history. Of those with data on travel history, 1,168 (85%) reported no travel preceding laboratory confirmation of SARS-CoV-2 and only 105 (8%) reported international travel during the 30 days preceding a positive SARS-CoV-2 test or symptom onset. International travel was reported by 92/1,304 (7%) of persons infected with the Alpha variant, 7/55 (22%) with Beta, and 5/9 (56%) with Gamma. Of the first three SARS-CoV-2 lineages designated as VOCs in the U.S., international travel was common only among the few Gamma cases. Most persons infected with Alpha and Beta variant reported no travel history, therefore, community transmission of these VOCs was likely common in the U.S. by March 2021. These findings underscore the importance of global surveillance using whole genome sequencing to detect and inform mitigation strategies for emerging SARS-CoV-2 VOCs.

Murder by radiation poisoning: implications for public health.

On November 23, 2006, former Russian military intelligence officer Alexander Litvinenko died in a London hospital. Authorities determined he was deliberately poisoned with the radionuclide Polonium-210 (210Po). Police subsequently discovered that those involved in this crime had--apparently inadvertently--spread 210Po over many locations in London. The United Kingdom Health Protection Agency (HPA) contacted many persons who might have been exposed to 210Po and provided voluntary urine testing. Some of those identified as potentially exposed were U.S. citizens, whom the HPA requested that the Centers for Disease Control and Prevention (CDC) assist in contacting. CDC also provided health care professionals and state and local public health officials with guidance as to how they might respond should a Litvinenko-like incident occur in the U.S. This guidance has resulted in the identification of a number of lessons that can be useful to public health and medical authorities in planning for radiological incidents. Eight such lessons are discussed in this article.

Medical response to a major radiologic emergency: a primer for medical and public health practitioners.

UNLABELLED: There are several types of serious nuclear or radiologic emergencies that would require a specialized medical response. Four scenarios of great public health, economic, and psychologic impact are the detonation of a nuclear weapon, the meltdown of a nuclear reactor, the explosion of a large radiologic dispersal device ("dirty bomb"), or the surreptitious placement of a radiation exposure device in a public area of high population density. With any of these, medical facilities that remain functional may have to deal with large numbers of ill, wounded, and probably contaminated people. Special care and/or handling will be needed for those with trauma, blast injuries, or thermal burns as well as significant radiation exposures or contamination. In addition, radiologists, nuclear medicine specialists, and radiation oncologists will be called on to perform a number of diverse and critically important tasks, including advising political and public health leaders, interfacing with the media, managing essential resources, and, of course, providing medical care. This article describes the medical responses needed following a radiologic or nuclear incident, including the symptoms of and specific treatments for acute radiation syndrome and other early health effects. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.09090330/-/DC1.

Acute radiation syndrome: assessment and management.

Primary care physicians may be unprepared to diagnose and treat rare, yet potentially fatal, illnesses such as acute radiation syndrome (ARS). ARS, also known as radiation sickness, is caused by exposure to a high dose of penetrating, ionizing radiation over a short period of time. The time to onset of ARS is dependent on the dose received, but even at the lowest doses capable of causing illness, this will occur within a matter of hours to days. This article describes the clinical manifestations of ARS, provides guidelines for assessing its severity, and makes recommendations for managing ARS victims.

DNA damage in leukocytes of workers occupationally exposed to 1-bromopropane.

1-bromopropane (1-BP; n-propyl bromide) (CAS No. 106-94-5) is an alternative to ozone-depleting chlorofluorocarbons that has a variety of potential applications as a degreasing agent for metals and electronics, and as a solvent vehicle for spray adhesives. Its isomer, 2-brompropane (2-BP; isopropyl bromide) (CAS No. 75-26-3) impairs antioxidant cellular defenses, enhances lipid peroxidation, and causes DNA damage in vitro. The present study had two aims. The first was to assess DNA damage in human leukocytes exposed in vitro to 1- or 2-BP. DNA damage was also assessed in peripheral leukocytes from workers with occupational exposure to 1-BP. In the latter assessment, start-of- and end-of-work week blood and urine samples were collected from 41 and 22 workers at two facilities where 1-BP was used as a solvent for spray adhesives in foam cushion fabrication. Exposure to 1-BP was assessed from personal-breathing zone samples collected for 1-3 days up to 8h per day for calculation of 8h time weighted average (TWA) 1-BP concentrations. Bromide (Br) was measured in blood and urine as a biomarker of exposure. Overall, 1-BP TWA concentrations ranged from 0.2 to 271 parts per million (ppm) at facility A, and from 4 to 27 ppm at facility B. The highest exposures were to workers classified as sprayers. 1-BP TWA concentrations were statistically significantly correlated with blood and urine Br concentrations. The comet assay was used to estimate DNA damage. In vitro, 1- or 2-BP induced a statistically significant increase in DNA damage at 1mM. In 1-BP exposed workers, start-of- and end-of-workweek comet endpoints were stratified based on job classification. There were no significant differences in DNA damage in leukocytes between workers classified as sprayers (high 1-BP exposure) and those classified as non-sprayers (low 1-BP exposure). At the facility with the high exposures, comparison of end-of-week values with start-of-week values using paired analysis revealed non-sprayers had significantly increased comet tail moments, and sprayers had significantly increased comet tail moment dispersion coefficients. A multivariate analysis included combining the data sets from both facilities, log transformation of 1-BP exposure indices, and the use of multiple linear regression models for each combination of DNA damage and exposure indices including exposure quartiles. The covariates were gender, age, smoking status, facility, and glutathione S-transferase M1 and T1 (GSTM1, GSTT1) polymorphisms. In the regression models, start-of-week comet tail moment in leukocytes was significantly associated with serum Br quartiles. End-of-week comet tail moment was significantly associated with 1-BP TWA quartiles, and serum Br quartiles. Gender, facility, and GSTM1 had a significant effect in one or more models. Additional associations were not identified from assessment of dispersion coefficients. In vitro and in vivo results provide limited evidence that 1-BP exposure may pose a small risk for increasing DNA damage.

Medical planning and response for a nuclear detonation: a practical guide.

This article summarizes major points from a newly released guide published online by the Office of the Assistant Secretary for Preparedness and Response (ASPR). The article reviews basic principles about radiation and its measurement, short-term and long-term effects of radiation, and medical countermeasures as well as essential information about how to prepare for and respond to a nuclear detonation. A link is provided to the manual itself, which in turn is heavily referenced for readers who wish to have more detail.

Triage and treatment tools for use in a scarce resources-crisis standards of care setting after a nuclear detonation.

Based on background information in this special issue of the journal, possible triage recommendations for the first 4 days following a nuclear detonation, when response resources will be limited, are provided. The series includes: modeling for physical infrastructure damage; severity and number of injuries; expected outcome of triage to immediate, delayed, or expectant management; resources required for treating injuries of varying severity; and how resource scarcity (particularly medical personnel) worsens outcome. Four key underlying considerations are: 1.) resource adequacy will vary greatly across the response areas by time and location; 2.) to achieve fairness in resource allocation, a common triage approach is important; 3.) at some times and locations, it will be necessary to change from "conventional" to "contingency" or "crisis" standards of medical care (with a resulting change in triage approach from treating the "sickest first" to treating those "most likely to survive" first); and 4.) clinical reassessment and repeat triage are critical, as resource scarcity worsens or improves. Changing triage order and conserving and allocating resources for both lifesaving and palliative care can maintain fairness, support symptomatic care, and save more lives. Included in this article are printable triage cards that reflect our recommendations. These are not formal guidelines. With new research, data, and discussion, these recommendations will undoubtedly evolve.

Educating medical staff about responding to a radiological or nuclear emergency.

A growing body of audience research reveals medical personnel in hospitals are unprepared for a large-scale radiological emergency such as a terrorist event involving radioactive or nuclear materials. Also, medical personnel in hospitals lack a basic understanding of radiation principles, as well as diagnostic and treatment guidelines for radiation exposure. Clinicians have indicated that they lack sufficient training on radiological emergency preparedness; they are potentially unwilling to treat patients if those patients are perceived to be radiologically contaminated; and they have major concerns about public panic and overloading of clinical systems. In response to these findings, the Centers for Disease Control and Prevention (CDC) has developed a tool kit for use by hospital medical personnel who may be called on to respond to unintentional or intentional mass-casualty radiological and nuclear events. This tool kit includes clinician fact sheets, a clinician pocket guide, a digital video disc (DVD) of just-in-time basic skills training, a CD-ROM training on mass-casualty management, and a satellite broadcast dealing with medical management of radiological events. CDC training information emphasizes the key role that medical health physicists can play in the education and support of emergency department activities following a radiological or nuclear mass-casualty event.

Overview of hazard assessment and emergency planning software of use to RN first responders.

There are numerous software tools available for field deployment, reach-back, training and planning use in the event of a radiological or nuclear terrorist event. Specialized software tools used by CBRNe responders can increase information available and the speed and accuracy of the response, thereby ensuring that radiation doses to responders, receivers, and the general public are kept as low as reasonably achievable. Software designed to provide health care providers with assistance in selecting appropriate countermeasures or therapeutic interventions in a timely fashion can improve the potential for positive patient outcome. This paper reviews various software applications of relevance to radiological and nuclear events that are currently in use by first responders, emergency planners, medical receivers, and criminal investigators.