The Dynamics of Infectious Diseases Associated With Injection Drug Use in Lawrence and Lowell, Massachusetts

Assessment of Bacterial Infections and Antibiotic Regimens in Intravenous Drug Users

Bacterial infections in people who inject drugs (PWID) are a significant cause of hospitalizations and increased morbidity in this group. In this review, we evaluated bacterial trends in the most common infections and appropriate empiric antibiotic coverage. Articles from PubMed and Google Scholar were curated in a Google document with shared access. Discussion and development of the paper were achieved over Zoom meetings. The common infections in PWID were skin and soft tissue infections (SSTIs), infective endocarditis, septic arthritis, osteomyelitis, and bloodstream infections (BSIs). The presence of comorbidities increased susceptibility to bacterial infections. Staphylococcus aureus was the predominant species in all the infections and included methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA). The current standard of antibiotic use for Staphylococcus species was found to be sufficient. The gram-negative bacillus Serratia marcescens was prevalent in PWID as a causative agent of septic arthritis, osteomyelitis, and infective endocarditis. Its treatment required a combination of β-lactam and either a fluoroquinolone or an aminoglycoside for a prolonged duration. Streptococci were commonly implicated in SSTIs and BSIs. The appropriate response was seen with β-lactam antibiotics. In PWID, Enterococcus and Pseudomonas were implicated in infective endocarditis of native and prosthetic valves. The former being difficult to treat, a new strategy of using dual β-lactam antibiotics was found to be supported by clinical data. Anti-pseudomonal antibiotics can be avoided in other infections seen in this group, as their prevalence was low. PWID, especially those with comorbidities, have an increased risk of acquiring infections with difficult-to-treat microbes. Therefore, empiric antibiotic treatment should be relevant to the infection, for which bacterial trends and antibiotic susceptibility must be reassessed periodically.

Early OxyContin Marketing Linked To Long-Term Spread Of Infectious Diseases Associated With Injection Drug Use

The initial marketing of the opioid analgesic OxyContin in 1996 increased fatal drug overdoses over the course of the opioid epidemic in the US. However, the long-term impacts of this marketing on complications of injection drug use, a key feature of the ongoing crisis, are undetermined. This study evaluated the effects of exposure to initial OxyContin marketing on the long-term trajectories of injection drug use-related outcomes in the US. We used a difference-in-differences analysis to compare outcomes in states with high versus low exposure to initial marketing before and after the 2010 reformulation of OxyContin, which facilitated the use of illicit drugs and the spread of infectious disease. Exposure to initial OxyContin marketing statistically significantly increased rates of fatal synthetic opioid-related overdoses; acute hepatitis A, B, and C viral infections; and infective endocarditis-related deaths. The greatest burden of adverse long-term outcomes has been in states that experienced the highest exposure to early OxyContin marketing. Our findings indicate that OxyContin marketing decisions from the mid-1990s increased viral and bacterial complications of injection drug use and illicit opioid-related overdose deaths twenty-five years later.

Patterns of Infectious Disease Associated With Injection Drug Use in Massachusetts

BACKGROUND

Since 2014, multiple outbreaks of human immunodeficiency virus (HIV) among people who inject drugs have occurred across the United States along with hepatitis C virus (HCV), skin and soft tissue infections (SSTIs), and infective endocarditis (IE), creating a converging public health crisis.

METHODS

We analyzed the temporal patterns of infectious disease and overdose using a hierarchical Bayesian distributed lag logistic regression model examining the probability that a given geographic area experienced at least 1 HIV case in a given month as a function of the counts/rates of overdose, HCV, SSTI, and IE and associated medical procedures at different lagged time periods.

RESULTS

Current-month HIV is associated with increasing HCV cases, abscess incision and drainage, and SSTI cases, in distinct temporal patterns. For example, 1 additional HCV case occurring 5 and 7 months previously is associated with a 4% increase in the odds of observing at least 1 current-month HIV case in a given locale (odds ratios, 1.04 [90% credible interval {CrI}: 1.01-1.10] and 1.04 [90% CrI: 1.00-1.09]). No such associations were observed for echocardiograms, IE, or overdose.

CONCLUSIONS

Lagged associations in other infections preceding rises in current-month HIV counts cannot be described as predictive of HIV outbreaks but may point toward newly discovered epidemics of injection drug use and associated clinical sequalae, prompting clinicians to screen patients more carefully for substance use disorder and associated infections.

Implementation of a bundle to improve HIV testing during hospitalization for people who inject drugs

Background

Increased HIV testing is essential to ending the HIV epidemic. People who inject drugs (PWID) are among the highest risk for HIV infection. Previous research at Tufts Medical Center identified low HIV testing rates in hospitalized PWID. Our research team aimed to identify and overcome barriers to inpatient HIV screening of PWID using implementation science methods.

Methods

Stakeholders were engaged to gather perspectives on barriers and facilitators of HIV testing. A PWID care bundle was developed and implemented, which included (1) HIV screening; (2) hepatitis A, B, and C testing and vaccination; (3) medications for opioid use disorder; and (4) naloxone prescription. Strategies from all nine Expert Recommendations for Implementing Change (ERIC) clusters guided the implementation plan. Stakeholder feedback was gathered throughout implementation, and implementation outcomes of acceptability and feasibility were assessed.

Results

PWID overall felt comfortable with HIV testing being offered while hospitalized. Clinicians cited that the main barriers to HIV testing were discomfort and confusion around consenting requirements. Many resident physicians surveyed reported that, at times, they forgot HIV testing for PWID. Overall, though, resident physicians felt that the PWID bundle was useful and did not distract from other patient care responsibilities.

Conclusions

Engagement of key stakeholders to increase HIV testing in an inpatient setting led to the implementation of a PWID bundle, which was feasible and acceptable. Bundling evidence-informed care elements for inpatient PWID should be investigated further.

Integrated Infectious Disease and Substance Use Disorder Care for the Treatment of Injection Drug Use-Associated Infections: A Prospective Cohort Study With Historical Control

Background

To address the infectious disease (ID) and substance use disorder (SUD) syndemic, we developed an integrated ID/SUD clinical team rooted in harm reduction at a county hospital in Miami, Florida. The Severe Injection-Related Infection (SIRI) team treats people who inject drugs (PWID) and provides medical care, SUD treatment, and patient navigation during hospitalization and after hospital discharge. We assessed the impact of the SIRI team on ID and SUD treatment and healthcare utilization outcomes.

Methods

We prospectively collected data on patients seen by the SIRI team. A diagnostic code algorithm confirmed by chart review was used to identify a historical control group of patients with SIRI hospitalizations in the year preceding implementation of the SIRI team. The primary outcome was death or readmission within 90 days post-hospital discharge. Secondary outcomes included initiation of medications for opioid use disorder (MOUD) and antibiotic course completion.

Results

There were 129 patients included in the study: 59 in the SIRI team intervention and 70 in the pre-SIRI team control group. SIRI team patients had a 45% risk reduction (aRR, 0.55 [95% confidence interval CI, .32-.95]; 24% vs 44%) of being readmitted in 90 days or dying compared to pre-SIRI historical controls. SIRI team patients were more likely to initiate MOUD in the hospital (93% vs 33%, P < .01), complete antibiotic treatment (90% vs 60%, P < .01), and less likely to have patient-directed discharge (17% vs 37%, P = .02).

Conclusions

An integrated ID/SUD team was associated with improvements in healthcare utilization, MOUD initiation, and antibiotic completion for PWID with infections.

Application of machine learning algorithms for localized syringe services program policy implementation - Florida, 2017

BACKGROUND

People who inject drugs (PWID) are at an amplified vulnerability for experiencing a multitude of harms related to their substance use, including viral (e.g. HIV, Hepatitis C) and bacterial infections (e.g. endocarditis). Implementation of evidence-based interventions, such as syringe services programs (SSPs), remains imperative, particularly in locations at an increased risk of HIV outbreaks. This study aims to identify communities in Florida that are high-priority locations for SSP implementation by examining state-level data related to the substance use and overdose crises.

METHODS

State-level surveillance data were aggregated at the ZIP Code Tabulation Area (ZCTA) (n = 983) for 2017. We used confirmed cases of acute HCV infection as a proxy of injection drug use. Least Absolute Selection and Shrinkage Operator (LASSO) regression was used to develop a machine learning model to identify significant indicators of acute HCV infection and high-priority areas for SSP implementation due to their increased vulnerability to an HIV outbreak.

RESULTS

The final model retained three variables of importance: (1) the number of drug-associated skin and soft tissue infection hospitalizations, (2) the number of chronic HCV infections in people aged 18-39, and 3) the number of drug-associated endocarditis hospitalizations. High-priority SSP implementation locations were identified in both urban and rural communities outside of current Ending the HIV Epidemic counties.

CONCLUSION

SSPs are long researched, safe, and effective evidence-based programs that offer a variety of services that reduce disease transmission and assist with combating the overdose crisis. Opportunities to increase services in needed regions across the state now exist in Florida as supported by the expansion of the Infectious Disease Elimination Act of 2019. This study provides details where potential areas of concern may be and highlights regions where future evidence-based harm reduction programs, such as SSPs, would be useful to reduce opioid overdoses and disease transmission among PWID.Key messagesThe rate of acute HCV in Florida in 2017 was 1.9 per 100,000, nearly twice the national average.Serious injection related infections among PWID are significant indicators of acute HCV infection.High-priority SSP implementation locations in Florida were identified in both urban and rural communities, including those outside of current Ending the HIV Epidemic counties.

Study on the Global Stability for a Generalized SEIR Epidemic Model

In the current study, a generalized SEIR epidemic model is studied. The generalized fractional-order SEIR model (susceptible-infected-recovered (SIR) epidemic) model differentiated the population into susceptible population, exposure population, infected population, and rehabilitation population and has fundamental mentoring importance for the forecast of the probable outburst of infectious ailments. The fundamental duplicated quantity R₀ is inferred. When R₀ < 1, the disease-free equilibrium (DFE) is particular and tending towards stability. When R₀ > 1, the endemic equilibrium is sole. In addition, certain circumstances are set up to make sure the local progressive stability of disease-free and endemic equilibrium. Considering the influence of the individual behavior, a broader SEIR epidemic model is raised, which classified the population into susceptible, exposure, infected, and rehabilitation. What is more, the basic reproduction number, that regulates whether the infection will die out or not, is obtained by the spectral radius of the next-generation matrix; moreover, the global stability of DFE and endemic equilibrium are analyzed by a geometry method.