Preventing the Spread: A Comprehensive Cancer Center's Journey to Prevent the Spread of Coronavirus Disease (Covid-19) During the 2020 Pandemic.

BACKGROUND: On March 11, 2020, the World Health Organization (WHO) declared Coronavirus Disease (COVID-19) a pandemic. Hospitals around the world began to implement infection prevention and control (IPC) measures to stop further spread and prevent infections within their facilities. Healthcare organizations were challenged to develop response plans, procure personal protective equipment (PPE) that was in limited supply while continuing to provide quality, safe care. METHODS: As a comprehensive cancer center with immunocompromised patients, our efforts began immediately. Preventative measures were established and, as of September 2020, over 14,000 patients have been tested within the facility. From March 2020 through September 2020, only one case of hospital acquired (HA) COVID-19 was identified among our patients. Two cases of suspected community acquired (SCA) cases were also identified. Following the Centers for Disease Control (CDC) guidance, IPC measures were implemented within the facility as information science about the virus developed. This article addresses the IPC measures taken, such as enhancing isolation precautions, implementing screening protocols, disinfecting and reusing N95 respirators, by the center throughout the pandemic as well as the challenges that arouse with a new and emerging infectious disease. CONCLUSIONS: The infection control measures implemented at our comprehensive cancer center during the COVID-19 pandemic allowed our center to continue to provide world class cancer care with minimal COVID-19 infection transmission among patients and team members.

Patch dynamics modeling framework from pathogens' perspective: Unified and standardized approach for complicated epidemic systems.

Mathematical models are powerful tools to investigate, simulate, and evaluate potential interventions for infectious diseases dynamics. Much effort has focused on the Susceptible-Infected-Recovered (SIR)-type compartment models. These models consider host populations and measure change of each compartment. In this study, we propose an alternative patch dynamic modeling framework from pathogens' perspective. Each patch, the basic module of this modeling framework, has four standard mechanisms of pathogen population size change: birth (replication), death, inflow, and outflow. This framework naturally distinguishes between-host transmission process (inflow and outflow) and within-host infection process (replication) during the entire transmission-infection cycle. We demonstrate that the SIR-type model is actually a special cross-sectional and discretized case of our patch dynamics model in pathogens' viewpoint. In addition, this patch dynamics modeling framework is also an agent-based model from hosts' perspective by incorporating individual host's specific traits. We provide an operational standard to formulate this modular-designed patch dynamics model. Model parameterization is feasible with a wide range of sources, including genomics data, surveillance data, electronic health record, and from other emerging technologies such as multiomics. We then provide two proof-of-concept case studies to tackle some of the existing challenges of SIR-type models: sexually transmitted disease and healthcare acquired infections. This patch dynamics modeling framework not only provides theoretical explanations to known phenomena, but also generates novel insights of disease dynamics from a more holistic viewpoint. It is also able to simulate and handle more complicated scenarios across biological scales such as the current COVID-19 pandemic.

Transmission patterns of COVID-19 in the mainland of China and the efficacy of different control strategies: a data- and model-driven study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) outbreak has seriously endangered the health and lives of Chinese people. In this study, we predicted the COVID-19 epidemic trend and estimated the efficacy of several intervention strategies in the mainland of China. METHODS: According to the COVID-19 epidemic status, we constructed a compartmental model. Based on reported data from the National Health Commission of People's Republic of China during January 10-February 17, 2020, we estimated the model parameters. We then predicted the epidemic trend and transmission risk of COVID-19. Using a sensitivity analysis method, we estimated the efficacy of several intervention strategies. RESULTS: The cumulative number of confirmed cases in the mainland of China will be 86 763 (95% CI: 86 067-87 460) on May 2, 2020. Up until March 15, 2020, the case fatality rate increased to 6.42% (95% CI: 6.16-6.68%). On February 23, 2020, the existing confirmed cases reached its peak, with 60 890 cases (95% CI: 60 350-61 431). On January 23, 2020, the effective reproduction number was 2.620 (95% CI: 2.567-2.676) and had dropped below 1.0 since February 5, 2020. Due to governmental intervention, the total number of confirmed cases was reduced by 99.85% on May 2, 2020. Had the isolation been relaxed from February 24, 2020, there might have been a second peak of infection. However, relaxing the isolation after March 16, 2020 greatly reduced the number of existing confirmed cases and deaths. The total number of confirmed cases and deaths would increase by 8.72 and 9.44%, respectively, due to a 1-day delayed diagnosis in non-isolated infected patients. Moreover, if the coverage of close contact tracing was increased to 100%, the cumulative number of confirmed cases would be decreased by 88.26% on May 2, 2020. CONCLUSIONS: The quarantine measures adopted by the Chinese government since January 23, 2020 were necessary and effective. Postponing the relaxation of isolation, early diagnosis, patient isolation, broad close-contact tracing, and strict monitoring of infected persons could effectively control the COVID-19 epidemic. April 1, 2020 would be a reasonable date to lift quarantine in Hubei and Wuhan.

Impact of Rapid Susceptibility Testing and Antibiotic Selection Strategy on the Emergence and Spread of Antibiotic Resistance in Gonorrhea.

Background: Increasing antibiotic resistance limits treatment options for gonorrhea. We examined the impact of a hypothetical point-of-care (POC) test reporting antibiotic susceptibility profiles on slowing resistance spread. Methods: A mathematical model describing gonorrhea transmission incorporated resistance emergence probabilities and fitness costs associated with resistance based on characteristics of ciprofloxacin (A), azithromycin (B), and ceftriaxone (C). We evaluated time to 1% and 5% prevalence of resistant strains among all isolates with the following: (1) empiric treatment (B and C), and treatment guided by POC tests determining susceptibility to (2) A only and (3) all 3 antibiotics. Results: Continued empiric treatment without POC testing was projected to result in >5% of isolates being resistant to both B and C within 15 years. Use of either POC test in 10% of identified cases delayed this by 5 years. The 3 antibiotic POC test delayed the time to reach 1% prevalence of triply-resistant strains by 6 years, whereas the A-only test resulted in no delay. Results were less sensitive to assumptions about fitness costs and test characteristics with increasing test uptake. Conclusions: Rapid diagnostics reporting antibiotic susceptibility may extend the usefulness of existing antibiotics for gonorrhea treatment, but ongoing monitoring of resistance patterns will be critical.

Effect of temperature on the occurrence and distribution of colorado potato beetle (Coleoptera: Chrysomelidae) in China.

Colorado potato beetle, Leptinotarsa decemlineata (Say), is the most destructive pest of potato in many countries of the world. It first invaded China from Kazakhstan in 1990s and now is a major pest of potato in many areas of Xinjiang Uygur Autonomous Region (Xinjiang). The objective of this study was to determine the effect of temperature on the spread of Colorado potato beetle in China after its invasion. Cold temperature in winter (December) and high temperature in summer (July) were analyzed in accordance with the absence and presence of Colorado potato beetle in Xinjiang. The boundary between the absence and presence of Colorado potato beetle in Xinjiang nearly coincided with the -8°C isotherm of monthly mean minimum temperature in winter. The stress of the low temperature in winter for Colorado potato beetle basically disappeared in the southeastern Hexi Corridor in Gansu Province of China, suggesting that the Hexi Corridor is the best channel to prevent any long-distance invasions of Colorado potato beetle into the Central Plains region. However, in Turpan City in northeastern Xinjiang, the extremely hot weather in the summer prevents the local colonization of Colorado potato beetle. Furthermore, according to our monitoring, high temperature in summer also limited Colorado potato beetle to diffuse eastward through Turpan. Results of this study suggest that it is essential to strengthen inspection and quarantine measures to prevent any artificial transmissions of Colorado potato beetle spreading eastward and thus to ensure the sustainable production of potato and other Solanaceae crops in northwest regions of China.

Sociodemographic characteristics and drug abuse patterns of treatment-seeking illicit drug abusers in Finland, 1997-2008: the Huuti study.

The epidemiological part of the Huume tietokanta (HUUTI) consortium research project is the first large-scale longitudinal study of treatment-seeking illicit drug abusers in Finland. The objective of this report was to describe the sociodemographic characteristics and drug abuse patterns of treatment-seeking clients at their first visit. This study analysed baseline data of 4817 clients (3365 men and 1452 women) aged 11-65 years who sought treatment for drug abuse between 1997 and 2008 at Helsinki Deaconess Institute. Data were collected using a structured questionnaire. The majority (56%) of clients were between 15 and 24 years, educated at elementary school level (75%), and unemployed (57%). Opiates (30%) were the primary drugs of abuse. The primary drugs were mostly injected (45%) and were abused daily during the past month (44%). Cannabis was the most common secondary drug of abuse (34%). The secondary drugs were predominantly smoked (39%) or taken orally (38%) and were abused once per week or less frequently during the past month (33%). Age at initiation of illicit drug abuse ranged from 5 to 49 years. Polydrug abuse was common, with a mean consumption of 3.5 concurrent polydrug use, which were combined from 3 or more drug classes. The prevalence of lifetime/ever intravenous drug abuse was 64% and past month intravenous drug abuse was 64%, respectively, and 13% reported sharing injecting equipment during the past month. Early initiation, polydrug abuse, and risky consumption of illicit drugs were major areas of concern among the study population. Injecting drug use could place considerable burden on health services in view of complications and transmission of infectious diseases.

Hospital networks and the dispersal of hospital-acquired pathogens by patient transfer.

Hospital-acquired infections (HAI) are often seen as preventable incidents that result from unsafe practices or poor hospital hygiene. This however ignores the fact that transmissibility is not only a property of the causative organisms but also of the hosts who can translocate bacteria when moving between hospitals. In an epidemiological sense, hospitals become connected through the patients they share. We here postulate that the degree of hospital connectedness crucially influences the rates of infections caused by hospital-acquired bacteria. To test this hypothesis, we mapped the movement of patients based on the UK-NHS Hospital Episode Statistics and observed that the proportion of patients admitted to a hospital after a recent episode in another hospital correlates with the hospital-specific incidence rate of MRSA bacteraemia as recorded by mandatory reporting. We observed a positive correlation between hospital connectedness and MRSA bacteraemia incidence rate that is significant for all financial years since 2001 except for 2008-09. All years combined, this correlation is positive and significantly different from zero (partial correlation coefficient r = 0.33 (0.28 to 0.38)). When comparing the referral pattern for English hospitals with referral patterns observed in the Netherlands, we predict that English hospitals more likely see a swifter and more sustained spread of HAIs. Our results indicate that hospitals cannot be viewed as individual units but rather should be viewed as connected elements of larger modular networks. Our findings stress the importance of cooperative effects that will have a bearing on the planning of health care systems, patient management and hospital infection control.

Optimal timing of disease transmission in an age-structured population.

It is a common medical folk-practice for parents to encourage their children to contract certain infectious diseases while they are young. This folk-practice is controversial, in part, because it contradicts the long-term public health goal of minimizing disease incidence. We study an epidemiological model of infectious disease in an age-structured population where virulence is age-dependent and show that, in some cases, the optimal behavior will increase disease transmission. This provides a rigorous justification of the concept of "endemic stability," and demonstrates that folk-practices may have been historically justified.

Results of a general hepatitis C lookback program for persons who received blood transfusions in a neonatal intensive care unit between January 1975 and July 1992.

OBJECTIVE: To notify persons who received a blood transfusion in a neonatal intensive care unit between January 1975 and July 1992 of their risk for hepatitis C infection and to encourage them to seek hepatitis C antibody testing. DESIGN: Neonatal intensive care unit, blood bank, and public access records were queried to identify current mailing addresses and persons deceased. All persons were notified by letter. SETTING: Anchorage, Alaska. PARTICIPANTS: Persons who received health care in an integrated health care system, the Alaska Native Medical Center, or in the private sector. Main Exposure Transfusion in the neonatal period. MAIN OUTCOME MEASURES: Prevalence of test results positive for the hepatitis C virus antibody and RNA and awareness of having received a blood transfusion in a neonatal intensive care unit. RESULTS: Alaska Native Medical Center (n = 401) and private sector (n = 1396) persons were targeted for notification. Letters were mailed to 277 Alaska Native Medical Center (69%) and 374 private sector (27%) persons, with 151 (55%) and 65 (17%) screened for hepatitis C, respectively. Among those screened (n = 216), 7 (3%) were hepatitis C antibody positive, with 6 (<3%) also hepatitis C virus-RNA positive. Among 147 persons who responded, 75 (51%) were unaware they had received a transfusion. CONCLUSIONS: Compared with the private sector, a higher proportion of persons were identified and tested from the integrated health care system and more than half of respondents were unaware of their transfusion history. It would be prudent to screen neonatal intensive care unit patients who received transfusions before July 1992 for hepatitis C virus infection.

Hepatitis A outbreak among MSM linked to casual sex and gay saunas in Copenhagen, Denmark.

During an outbreak of hepatitis A predominantly among men who have sex with men (MSM) in Copenhagen, Denmark, in 2004, we did a case-control study to determine risk factors for infection. A case was an MSM >17 years, living in Copenhagen, with IgM positive hepatitis A infection diagnosed between June and August 2004, and without a household contact with a hepatitis A case before onset of illness. Controls were selected at the Copenhagen Pride Festival. The study included 18 cases and 64 controls. Sixteen of 18 cases and 36/63 controls had sex with casual partners (ORMH 5.6, 95% CI 1.2-26.9). Eleven of 18 cases and 14/62 controls had sex in gay saunas (ORMH 4.2, 95% CI 1.5-11.5). Sex at private homes appeared to be protective (ORMH 0.2, 95% CI 0.1-0.7). Casual sex including sex in gay saunas was an important risk factor for the spread of HAV among MSM in Copenhagen. The results are in accordance with findings in other European outbreaks. As the general immunity to hepatitis A decreases and the outbreak potential increases, we recommend health education and hepatitis A vaccination to all MSM not living in monogamous relationships, especially if they visit gay saunas or other places with frequent partner change. To stop spread of hepatitis A among MSM in Europe, a European consensus on prevention and control measures may be required.

Hepatitis C virus prevalence and outcomes among injecting drug users on opioid replacement therapy.

OBJECTIVES: To determine hepatitis C virus (HCV) prevalence among injecting drug users (IDUs) receiving opioid replacement therapy in a referred office setting, and assess potential needs for hepatitis C treatment and care. METHODS: Data were collected on 178 IDUs receiving opioid replacement therapy who underwent clinical assessment between January 2002 and June 2003. Standard clinic protocols included HCV and hepatitis B virus (HBV) serology, liver biochemistry and HCV RNA analysis for patients with a positive HCV antibody and normal alanine aminotransferase (ALT) levels. RESULTS: HCV prevalence was 75.3%, similar for males (75.5%) and females (74.4%), and increased with age from 60.8% for 19-30 years to 93.9% above 40 years. Among patients with HCV antibodies and no prior HCV antiviral therapy (n = 130), 53.1% had normal ALT levels and 25.4% were HCV-RNA negative. Older patients were more likely to have normal ALT levels (P = 0.02), and be HCV-RNA negative (P = 0.02). Younger patients were more likely to have been HBV vaccinated (P < 0.001), however, were less likely to have either vaccine or natural immunity (P = 0.006). Of 97 patients with probable chronic HCV infection, 58 patients met pre-liver biopsy criteria for HCV treatment, 34 had relative contraindications to treatment and 6 had been referred for treatment assessment. CONCLUSION: Clinical characterization in a setting of high HCV prevalence has enabled the differentiation of patients into groups with no evidence of HCV viraemia, with chronic HCV infection, and those most appropriate for HCV treatment referral. These clinical assessments along with appropriate referral should be instituted in drug dependency treatment settings.

The public health impact of prion diseases.

Several prion disease-related human health risks from an exogenous source can be identified in the United States, including the iatrogenic transmission of Creutzfeldt-Jakob disease (CJD), the possible occurrence of variant CJD (vCJD), and potential zoonotic transmission of chronic wasting disease (CWD). Although cross-species transmission of prion diseases seems to be limited by an apparent "species barrier," the occurrence of bovine spongiform encephalopathy (BSE) and its transmission to humans indicate that animal prion diseases can pose a significant public health risk. Recent reports of secondary person-to-person spread of vCJD via blood products and detection of vCJD transmission in a patient heterozygous at codon 129 further illustrate the potential public health impacts of BSE.