The Arbovirus Mapping and Prediction (ArboMAP) system for West Nile virus forecasting

Objectives

West Nile virus (WNV) is the most common mosquito-borne disease in the United States. Predicting the location and timing of outbreaks would allow targeting of disease prevention and mosquito control activities. Our objective was to develop software (ArboMAP) for routine WNV forecasting using public health surveillance data and meteorological observations.

Materials and Methods

ArboMAP was implemented using an R markdown script for data processing, modeling, and report generation. A Google Earth Engine application was developed to summarize and download weather data. Generalized additive models were used to make county-level predictions of WNV cases.

Results

ArboMAP minimized the number of manual steps required to make weekly forecasts, generated information that was useful for decision-makers, and has been tested and implemented in multiple public health institutions.

Discussion and Conclusion

Routine prediction of mosquito-borne disease risk is feasible and can be implemented by public health departments using ArboMAP.

An Outbreak Investigation of Vibrio parahaemolyticus Infections in the United States Linked to Crabmeat Imported from Venezuela: 2018

Vibrio parahaemolyticus is the leading cause of seafood-related foodborne illness globally. In 2018, the U.S. federal, state, and local public health and regulatory partners investigated a multistate outbreak of V. parahaemolyticus infections linked to crabmeat that resulted in 26 ill people and nine hospitalizations. State and U.S. Food and Drug Administration (FDA) laboratories recovered V. parahaemolyticus, Salmonella spp., and Listeria monocytogenes isolates from crabmeat samples collected from various points of distribution and conducted phylogenetic analyses of whole-genome sequencing data. Federal, state, and local partners conducted traceback investigations to determine the source of crabmeat. Multiple Venezuelan processors that supplied various brands of crabmeat were identified, but a sole firm was not confirmed as the source of the outbreak. Travel restrictions between the United States and Venezuela prevented FDA officials from conducting on-site inspections of cooked crabmeat processors. Based on investigation findings, partners developed public communications advising consumers not to eat crabmeat imported from Venezuela and placed potentially implicated firms on import alerts. While some challenges limited the scope of the investigation, epidemiologic, traceback, and laboratory evidence identified the contaminated food and country of origin, and contributed to public health and regulatory actions, preventing additional illnesses. This multistate outbreak illustrates the importance of adhering to appropriate food safety practices and regulations for imported seafood.

COVID-19 Outbreaks Linked to Workplaces, 23 US Jurisdictions, August-October 2021

OBJECTIVES

Early in the COVID-19 pandemic, several outbreaks were linked with facilities employing essential workers, such as long-term care facilities and meat and poultry processing facilities. However, timely national data on which workplace settings were experiencing COVID-19 outbreaks were unavailable through routine surveillance systems. We estimated the number of US workplace outbreaks of COVID-19 and identified the types of workplace settings in which they occurred during August-October 2021.

METHODS

The Centers for Disease Control and Prevention collected data from health departments on workplace COVID-19 outbreaks from August through October 2021: the number of workplace outbreaks, by workplace setting, and the total number of cases among workers linked to these outbreaks. Health departments also reported the number of workplaces they assisted for outbreak response, COVID-19 testing, vaccine distribution, or consultation on mitigation strategies.

RESULTS

Twenty-three health departments reported a total of 12 660 workplace COVID-19 outbreaks. Among the 12 470 workplace types that were documented, 35.9% (n = 4474) of outbreaks occurred in health care settings, 33.4% (n = 4170) in educational settings, and 30.7% (n = 3826) in other work settings, including non-food manufacturing, correctional facilities, social services, retail trade, and food and beverage stores. Eleven health departments that reported 3859 workplace outbreaks provided information about workplace assistance: 3090 (80.1%) instances of assistance involved consultation on COVID-19 mitigation strategies, 1912 (49.5%) involved outbreak response, 436 (11.3%) involved COVID-19 testing, and 185 (4.8%) involved COVID-19 vaccine distribution.

CONCLUSIONS

These findings underscore the continued impact of COVID-19 among workers, the potential for work-related transmission, and the need to apply layered prevention strategies recommended by public health officials.

Rapid Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 in Detention Facility, Louisiana, USA, May-June, 2020

To assess transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a detention facility experiencing a coronavirus disease outbreak and evaluate testing strategies, we conducted a prospective cohort investigation in a facility in Louisiana, USA. We conducted SARS-CoV-2 testing for detained persons in 6 quarantined dormitories at various time points. Of 143 persons, 53 were positive at the initial test, and an additional 58 persons were positive at later time points (cumulative incidence 78%). In 1 dormitory, all 45 detained persons initially were negative; 18 days later, 40 (89%) were positive. Among persons who were SARS-CoV-2 positive, 47% (52/111) were asymptomatic at the time of specimen collection; 14 had replication-competent virus isolated. Serial SARS-CoV-2 testing might help interrupt transmission through medical isolation and quarantine. Testing in correctional and detention facilities will be most effective when initiated early in an outbreak, inclusive of all exposed persons, and paired with infection prevention and control.

Public Health Response to COVID-19 Cases in Correctional and Detention Facilities - Louisiana, March-April 2020

Correctional and detention facilities face unique challenges in the control of infectious diseases, including coronavirus disease 2019 (COVID-19) (1-3). Among >10 million annual admissions to U.S. jails, approximately 55% of detainees are released back into their communities each week (4); in addition, staff members at correctional and detention facilities are members of their local communities. Thus, high rates of COVID-19 in correctional and detention facilities also have the potential to influence broader community transmission. In March 2020, the Louisiana Department of Health (LDH) began implementing surveillance for COVID-19 among correctional and detention facilities in Louisiana and identified cases and outbreaks in many facilities. In response, LDH and CDC developed and deployed the COVID-19 Management Assessment and Response (CMAR) tool to guide technical assistance focused on infection prevention and control policies and case management with correctional and detention facilities. This report describes COVID-19 prevalence in correctional and detention facilities detected through surveillance and findings of the CMAR assessment. During March 25-April 22, 489 laboratory-confirmed COVID-19 cases, including 37 (7.6%) hospitalizations and 10 (2.0%) deaths among incarcerated or detained persons, and 253 cases, including 19 (7.5%) hospitalizations and four (1.6%) deaths among staff members were reported. During April 8-22, CMAR telephone-based assessments were conducted with 13 of 31 (42%) facilities with laboratory-confirmed cases and 11 of 113 (10%) facilities without known cases. Administrators had awareness and overall understanding of CDC guidance for prevention of transmission in these facilities but reported challenges in implementation, related to limited space to quarantine close contacts of COVID-19 patients and inability of incarcerated and detained persons to engage in social distancing, particularly in dormitory-style housing. CMAR was a useful tool that helped state and federal public health officials assist multiple correctional and detention facilities to better manage COVID-19 patients and guide control activities to prevent or mitigate transmission.

COVID-19 in Correctional and Detention Facilities - United States, February-April 2020

An estimated 2.1 million U.S. adults are housed within approximately 5,000 correctional and detention facilities^† on any given day (1). Many facilities face significant challenges in controlling the spread of highly infectious pathogens such as SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19). Such challenges include crowded dormitories, shared lavatories, limited medical and isolation resources, daily entry and exit of staff members and visitors, continual introduction of newly incarcerated or detained persons, and transport of incarcerated or detained persons in multiperson vehicles for court-related, medical, or security reasons (2,3). During April 22-28, 2020, aggregate data on COVID-19 cases were reported to CDC by 37 of 54 state and territorial health department jurisdictions. Thirty-two (86%) jurisdictions reported at least one laboratory-confirmed case from a total of 420 correctional and detention facilities. Among these facilities, COVID-19 was diagnosed in 4,893 incarcerated or detained persons and 2,778 facility staff members, resulting in 88 deaths in incarcerated or detained persons and 15 deaths among staff members. Prompt identification of COVID-19 cases and consistent application of prevention measures, such as symptom screening and quarantine, are critical to protecting incarcerated and detained persons and staff members.

Expanded Molecular Testing on Patients with Suspected West Nile Virus Disease

Most diagnostic testing for West Nile virus (WNV) disease is accomplished using serologic testing, which is subject to cross-reactivity, may require cumbersome confirmatory testing, and may fail to detect infection in specimens collected early in the course of illness. The objective of this project was to determine whether a combination of molecular and serologic testing would increase detection of WNV disease cases in acute serum samples. A total of 380 serum specimens collected ≤7 days after onset of symptoms and submitted to four state public health laboratories for WNV diagnostic testing in 2014 and 2015 were tested. WNV immunoglobulin M (IgM) antibody and RT-PCR tests were performed on specimens collected ≤3 days after symptom onset. WNV IgM antibody testing was performed on specimens collected 4-7 days after onset and RT-PCR was performed on IgM-positive specimens. A patient was considered to have laboratory evidence of WNV infection if they had detectable WNV IgM antibodies or WNV RNA in the submitted serum specimen. Of specimens collected ≤3 days after symptom onset, 19/158 (12%) had laboratory evidence of WNV infection, including 16 positive for only WNV IgM antibodies, 1 positive for only WNV RNA, and 2 positive for both. Of specimens collected 4-7 days after onset, 21/222 (9%) were positive for WNV IgM antibodies; none had detectable WNV RNA. These findings suggest that routinely performing WNV RT-PCR on acute serum specimens submitted for WNV diagnostic testing is unlikely to identify a substantial number of additional cases beyond IgM antibody testing alone.