Community outbreak of COVID-19 among people who use drugs attending a harm reduction centre in Barcelona, Spain.

BACKGROUND: The COVID-19 pandemic particularly affected the health of vulnerable population, such as people who use drugs. Due to compromised baseline health status, certain drug uses and settings and socioeconomic deprivation related to poverty and homelessness, drug users faced higher risk of COVID-19 infection. They had difficulty in adhering to the public health measures (i.e. physical distancing, hand hygiene and mask use). Also, the struggle to implement non-pharmaceutical actions (i.e. test-trace-isolate-quarantine strategy) among SARS-COV-2-infected drug users and their close contacts challenged the public health response. Therefore, this study aimed to describe a community COVID-19 outbreak and its approach among drug users of a harm reduction programme in an outpatient drug treatment centre in Barcelona, Spain. METHODS: We conducted an observational descriptive study of an outbreak of COVID-19 among people who use drugs attending the harm reduction programme of an outpatient drug treatment centre in the city of Barcelona, between July and October 2021 (n = 440). A passive search for cases was carried out with rapid antigens tests targeting symptomatic users who attended the facilities. RESULTS: Nineteen positive COVID-19 cases were identified among symptomatic drug users, between July and October 2021, with an attack rate of 4.3%. Specific measures were taken to control the outbreak, such as offering accommodation to self-isolate in a low-threshold residential resource to homeless drug users who tested positive and intensifying the vaccination strategy. The management of the outbreak was carried out in close collaboration between the outpatient centre and the main public health stakeholders in the city of Barcelona. CONCLUSIONS: This study shows the complexity of managing and investigating COVID-19 outbreaks in vulnerable population groups. Epidemiological control measures, such as the test-trace-isolate-quarantine strategy, were challenging to implement due to technology-related barriers and socioeconomic vulnerabilities, especially homelessness. Community-based interventions, cooperation among stakeholders and housing-related policies were helpful in tackling outbreaks among people who use drugs. When addressing vulnerable and hidden populations, the perspective of inequalities should be included in epidemiological surveillance and outbreak control strategies.

Impact of 24-hour schedule of a drug consumption room on service use and number of non-fatal overdoses. A quasiexperimental study in Barcelona.

BACKGROUND: The opening hours of drug consumption rooms could constitute a barrier to access among people who use drugs (PWUD). CAS Baluard is an outpatient substance use care center in Barcelona, which provides a drug consumption room in Barcelona among other services. The objectives of our study were to compare the client profile, the facility use, the drugs used, and the number of non-fatal overdose episodes between (1) a 15-hour opening period of a drug consumption room versus a 24-hour opening period; and (2) between daytime and nighttime during the 24-hour period. METHODS: Data from CAS Baluard was obtained from March-June (15-hour opening period) and July-October (24-hour opening period), 2018. The sociodemographic characteristics of clients were gathered in both periods and in the daytime and nighttime client groups in the 24-hour period. Finally, associations were estimated between facility use and period and between facility use and opening hours. RESULTS: There were 1,089 clients in the 15-hour period and 1,262 in the 24-hour period. There were no sociodemographic differences in the clients between periods. During nighttime, there was a higher proportion of women (17%) and homeless people (47%) than during daytime (12% and 30%, respectively). Injected cocaine use was more frequent during nighttime (34%) than during daytime (25%) and injected heroin use was less frequent during nighttime (17%) than during daytime (24%). There was a non-significant increase in non-fatal overdose risk during nighttime (PR 3.9 95%CI 0.98-15.64). However, when we analyzed heroin use alone, the increase in non-fatal overdose risk was significant (PR 4.69 95%CI 1.17-18.75). CONCLUSION: During nighttime, attendance at the facility was higher among women, homeless people, and people who used stimulants. Our results point to a possible increase in overdose risk during nighttime, when most drug consumption rooms are closed.