Susceptibility to Hepatitis A and B Virus Among Clients at a Syringe Services Program in Philadelphia, 2018

Abstract

Objectives Although many people who use drugs meet criteria for vaccination against hepatitis A virus (HAV) and hepatitis B virus (HBV), estimates of susceptibility (ie, lack of immunity) are not well established. This study sought to identify the prevalence of and characteristics associated with HAV and HBV susceptibility among people who use drugs attending an urban syringe services program. Methods We initiated this seroprevalence study in 2018 among 438 clients of a syringe services program who met study criteria, including provision of a blood specimen and a self-reported history of drug use. We assessed HAV and HBV susceptibility and infection via serological testing. We examined associations between participant characteristics and serology status by using descriptive statistics and multivariable logistic regression models. Results Of the initial 438 clients identified, 353 (80.6%) met study criteria. Of 352 participants with conclusive HAV test results, 48.6% (n = 171) were HAV susceptible; of 337 participants with conclusive HBV test results, 32.6% (n = 110) were HBV susceptible, 24.3% (n = 82) showed evidence of past or present HBV infection, and 43.0% (n = 145) had vaccine-derived immunity. Compared with participants born before 1970, participants born during 1980-1989 had 5.90 (95% CI, 2.42-14.40) times the odds of HAV susceptibility and 0.18 (95% CI, 0.06-0.53) times the odds of HBV susceptibility, and participants born during 1990-1999 had 6.31 (95% CI, 2.34-17.00) times the odds of HAV susceptibility. Decreased odds of HAV susceptibility were associated with homelessness (adjusted odds ratio = 0.48; 95% CI, 0.28-0.82). Conclusion Despite applicable HAV and HBV vaccination recommendations, substantial gaps exist in HAV and HBV susceptibility among a population of people who use drugs. These findings highlight the need for increased HAV and HBV vaccination efforts among people who use drugs.

Dismantling Barriers to Hepatitis B and Delta Screening, Prevention, and Linkage to Care among the PWUD Community in Philadelphia

“…In a 2018 study conducted by the Philadelphia Department of Public Health to better understand susceptibility to hepatitis A and B viruses among PWUD in Philadelphia, 32.6% of study participants were found to be susceptible to hepatitis B. This study also revealed that 43% of individuals tested had evidence of HBV vaccine-derived immunity, and 24.3% had recovered from past HBV infection [ 5 ]. These results align closely with the results of the present study but do demonstrate a notable decline in susceptibility and an increase in vaccine-derived immunity and underscore the benefits of coordination and collaboration with public health departments, especially for the provision and administration of vaccines, which was found in the present study to be vital to the successful connection of individuals susceptible to hepatitis B with vaccines.…”

“…People who use drugs (PWUD), and particularly people who inject drugs (PWID), are susceptible to blood-borne viruses, as unsafe injection practices, such as using unsterile needles and re-using syringes, increase one’s risk of exposure to viral infections. Other factors, such as unsafe sexual practices, including transactional sex (typically necessitated by social and financial circumstances), as well as homelessness and a history of incarceration, can also heighten the risk of exposure to viral infections in this population [ 3 , 4 , 5 , 6 , 7 , 8 ]. The most common of these exposures are to human immunodeficiency virus (HIV) and hepatitis B, C, and delta [ 9 ].…”

Supporting syringe services programs in the initiation and scale-up of vaccine administration: findings from in-depth interviews

“…Despite elevated risks of viral hepatitis among people who use drugs and the availability of effective vaccines, recent studies documented vaccination rates of 32-51% for hepatitis A and 35-56% for hepatitis B among this population [10][11][12]. Accelerated vaccination schedules and incentives have been used to increase vaccination rates for hepatitis B among persons who inject drugs successfully [13].…”

Determining Herd Immunity Thresholds for Hepatitis A Virus Transmission to Inform Vaccination Strategies Among People Who Inject Drugs in 16 US States

“…Therefore, although vaccination coverage among adolescents (aged 13–17 years in 2021) is 85% (2-dose coverage [ 13 ]), it is substantially lower among adults (aged ≥19 years in 2018; 2-dose coverage, 11.9% [ 14 ]). Additionally, due to recognition of PWUD (injection and noninjection) as a population at high risk of HAV infection, PWUD have been recommended for vaccination since 1996 [ 12 ], yet vaccination coverage among this group remains suboptimal [ 15–17 ]. Transmission between PWUD can occur through multiple routes, such as close contact with lack of access to hygiene facilities, housing, and barriers to obtaining clean supplies, in addition to potential modes of ingestion of contaminated drugs, sharing contaminated supplies, and sexual contact [ 18 ].…”

“…Transmission between PWUD can occur through multiple routes, such as close contact with lack of access to hygiene facilities, housing, and barriers to obtaining clean supplies, in addition to potential modes of ingestion of contaminated drugs, sharing contaminated supplies, and sexual contact [ 18 ]. Among this population, recent estimates indicate that more than 50% of people who inject drugs (PWID) remain at risk for HAV infection [ 15–17 ]. Given the high and ongoing number of HAV outbreaks among PWID (a subset of PWUD) in the United States, this population remains of particular public health concern regarding provision of appropriate prevention efforts.…”