Infectious diseases occurring in the context of substance use disorders: A concise review

Prevalence of infectious diseases is substantially higher among patients with substance use disorders (SUD). Factors associated with drug use including sharing needles and injecting supplies, presence of contaminants in drugs and drug use related paraphernalia, risky behaviors associated with drug use, immune suppression secondary to chronic drug use, poverty and homelessness all increase the risk of infections. Persons with SUD have low rates of health care utilization and may miss opportunities for early diagnosis and care of infectious complications of substance use. When infectious diseases are comorbid with drug use, they are associated with substantial morbidity and mortality and result in significant healthcare costs. Patients with SUD may be rescued from an overdose, detoxified or treated for a SUD but facilities and clinicians are often reluctant to assume responsibility for evaluation and treatment of concurrent infectious or medical diseases. Increased screening for these disorders, utilizing vaccinations and other preventative strategies including clean supplies and safe injecting sites and providing comprehensive substance use and infectious disease treatment have the potential to significantly improve patient related outcomes and enhance public health. In this paper we review the prevalence of various common infectious diseases among persons who use drugs, their clinical presentation, mode of transmission, screening and diagnosis. We detail some of the common mechanisms by which persons who use drugs are at increased risk of contracting infections. We also discuss preventive and treatment strategies for infectious diseases occurring in the context of SUD.