Responding to measles outbreaks in the United States puts a considerable strain on public health resources, and limited research exists about the effectiveness of containment strategies. In this paper we quantify the impact of isolation, contact tracing, and exclusion in reducing transmission during a measles outbreak in an under-vaccinated community.
BACKGROUND: Screening for asymptomatic Chlamydia trachomatis (Ct) among men has not been recommended because feasibility and efficacy are unknown. Check It is a seek-test-treat community-based Ct screening program for African American men who have sex with women and who are 15 to 24 years of age. This is an evaluation of adaptations made to the program aimed at improving index/partner notification and treatment rates.
METHODS: The original Check It intervention included free testing and treatment, contact tracing performed by a third party, expedited index therapy, and expedited partner therapy via pharmacy pickup. The intervention was adapted after a series of in-depth interviews eliciting information to refine the program. Changes included continuity of testing, notification, and treatment by the same staff; expanded hours; and patient-delivered partner therapy with a medication mail-delivery option. Rates of index male and partner treatment were compared using log-binomial models and generalized estimating equations.
RESULTS: Men in the adapted intervention (n = 85) were more likely than men in the original intervention (n = 99) to be contacted (relative risk [RR], 1.14; 95% confidence interval [CI], 1.02-1.27), make a treatment plan (RR, 1.14; 95% CI, 1.01-1.27), and complete treatment (RR, 1.45; 95% CI, 1.20-1.75). Female sexual partners were significantly more likely to complete treatment in postadaptation (n = 153) compared with preadaptation (n = 161; RR, 3.02; 95% CI, 1.81-5.05).
CONCLUSIONS: Compared with third-party notification and expedited index therapy/expedited partner therapy available by pharmacy pickup only, patient-delivered partner therapy with mail-delivery option, staff available at nontraditional hours, and staff continuity across testing, notification, and treatment significantly improved index and partner treatment completion.
BACKGROUND: Non-pharmaceutical interventions (NPIs) are used to reduce transmission of SARS coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19). However, empirical evidence of the effectiveness of specific NPIs has been inconsistent. We assessed the effectiveness of NPIs around internal containment and closure, international travel restrictions, economic measures, and health system actions on SARS-CoV-2 transmission in 130 countries and territories.
METHODS: We used panel (longitudinal) regression to estimate the effectiveness of 13 categories of NPIs in reducing SARS-CoV-2 transmission using data from January to June 2020. First, we examined the temporal association between NPIs using hierarchical cluster analyses. We then regressed the time-varying reproduction number (Rt) of COVID-19 against different NPIs. We examined different model specifications to account for the temporal lag between NPIs and changes in Rt, levels of NPI intensity, time-varying changes in NPI effect, and variable selection criteria. Results were interpreted taking into account both the range of model specifications and temporal clustering of NPIs.
RESULTS: There was strong evidence for an association between two NPIs (school closure, internal movement restrictions) and reduced Rt. Another three NPIs (workplace closure, income support, and debt/contract relief) had strong evidence of effectiveness when ignoring their level of intensity, while two NPIs (public events cancellation, restriction on gatherings) had strong evidence of their effectiveness only when evaluating their implementation at maximum capacity (e.g. restrictions on 1000+ people gathering were not effective, restrictions on < 10 people gathering were). Evidence about the effectiveness of the remaining NPIs (stay-at-home requirements, public information campaigns, public transport closure, international travel controls, testing, contact tracing) was inconsistent and inconclusive. We found temporal clustering between many of the NPIs. Effect sizes varied depending on whether or not we included data after peak NPI intensity.
CONCLUSION: Understanding the impact that specific NPIs have had on SARS-CoV-2 transmission is complicated by temporal clustering, time-dependent variation in effects, and differences in NPI intensity. However, the effectiveness of school closure and internal movement restrictions appears robust across different model specifications, with some evidence that other NPIs may also be effective under particular conditions. This provides empirical evidence for the potential effectiveness of many, although not all, actions policy-makers are taking to respond to the COVID-19 pandemic.
Nigeria accounts for 11% of the worldwide gap between estimated and reported individuals with tuberculosis (TB). Hard-to-reach communities on the Southern Nigeria coast experience many difficulties accessing TB services. We implemented an active case finding (ACF) intervention in Akwa Ibom and Cross River states utilizing three approaches: house-to-house/tent-to-tent screening, community outreach and contact investigation. To evaluate the impact, we compared TB notifications in intervention areas to baseline and control population notifications, as well as to expected notifications based on historical trends. We also gathered field notes from discussions with community volunteers who provided insights on their perspectives of the intervention. A total of 509,768 individuals were screened of which 12,247 (2.4%) had TB symptoms and 11,824 (96.5%) were tested. In total, 1015 (8.6%) of those identified as presumptive had confirmed TB-98.2% initiated treatment. Following implementation, TB notifications in intervention areas increased by 112.9% compared to baseline and increased by 138.3% when compared to expected notifications based on historical trends. In contrast, control population notifications increased by 101% and 49.1%, respectively. Community volunteers indicated a preference for community outreach activities. Multi-faceted, community-based interventions in Nigeria's coastal areas successfully increase TB detection for communities with poor access to health services.
Childhood tuberculosis (TB) is consistently under-detected in most high-burden countries, including Uganda, especially in young children at high risk for severe disease and mortality. TB preventive treatment (TPT) for high-risk child contacts is also poorly implemented. The centralised concentration of services for child TB at the referral level is a major challenge in the prevention, detection and treatment of TB in children. In 2015, the DETECT Child TB Project was implemented in two districts of Uganda and involved decentralisation of healthcare services for child TB from tertiary to primary healthcare facilities, along with establishing linkages to support community-based household contact screening and management. The intervention resulted in improved case finding of child and adult TB cases, improved treatment outcomes for child TB and high uptake and completion of TPT for eligible child contacts. A detailed description of the development and implementation of this project is provided, along with findings from an external evaluation. The ongoing mentorship and practical support for health workers to deliver optimal services in this context were critical to complement the use of training and training tools. A summary of the project's outcomes is provided along with the key challenges identified and the lessons learnt.
OBJECTIVES: We investigated the effects of an enhanced partner notification (PN) counselling intervention with the offer of provider-assisted referral among people diagnosed with STI in a Cape Town public clinic.
METHODS: Participants were adults diagnosed with STI at a community clinic. After the standard STI consultation, participants were randomly allocated in a 1:1:1 ratio to (1) 'HE': 20 min health education; (2) 'RR': 45 min risk reduction skills counselling; or (3) 'ePN': 45 min enhanced partner notification communication skills counselling and the offer of provider-assisted referral. The primary outcome was the incidence of repeat STI diagnoses during the 12 months after recruitment, and the secondary outcome was participants' reports 2 weeks after diagnosis of notifying recent partners. Incidence rate ratios (IRRs) were used to compare the incidence rates between arms using a Poisson regression model.
RESULTS: The sample included 1050 participants, 350 per group, diagnosed with STI between June 2014 and August 2017. We reviewed 1048 (99%) participant records, and identified 136 repeat STI diagnoses in the ePN arm, 138 in the RR arm and 141 in the HE arm. There was no difference in the annual incidence of STI diagnosis between the ePN and HE arms (IRR: 1.0; 95% CI 0.7 to 1.3), or between the RR and HE arms (IRR: 0.9; 95% CI 0.7 to 1.2). There was a greater chance of a partner being notified in the ePN condition compared with the HE condition, 64.3% compared with 53.8%, but no difference between the RR and HE arms.
CONCLUSIONS: PN counselling and education with provider-assisted services has the potential to change the behaviour of people diagnosed with STIs, increasing the number of partners they notify by more than 10%. However, these changes in behaviour did not lead to a reduction of repeat STI diagnoses.
TRIAL REGISTRATION NUMBER: PACTR201606001682364.
The COVID-19 pandemic has seen digital contact tracing emerge around the world to help prevent spread of the disease. A mobile phone app records proximity events between app users, and when a user tests positive for COVID-19, their recent contacts can be notified instantly. Theoretical evidence has supported this new public health intervention1-6, but its epidemiological impact has remained uncertain7. Here we investigated the impact of the NHS COVID-19 app for England and Wales, from its launch on 24 September 2020 through to the end of December 2020. It was used regularly by approximately 16.5 million users (28% of the total population), and sent approximately 1.7 million exposure notifications: 4.4 per index case consenting to contact tracing. We estimated that the fraction of app-notified individuals subsequently showing symptoms and testing positive (the secondary attack rate, SAR) was 6.0%, comparable to the SAR for manually traced close contacts. We estimated the number of cases averted by the app using two complementary approaches. Modelling based on the notifications and SAR gave 284,000 (108,000-450,000), and statistical comparison of matched neighbouring local authorities gave 594,000 (317,000-914,000). Roughly one case was averted for each case consenting to notification of their contacts. We estimated that for every percentage point increase in app users, the number of cases can be reduced by 0.8% (modelling) or 2.3% (statistical analysis). These findings provide evidence for continued development and deployment of such apps in populations that are awaiting full protection from vaccines.
INTRODUCTION: HIV diagnosis is the necessary first step towards HIV care initiation, yet many persons living with HIV (PLWH) remain undiagnosed. Employing multiple HIV testing strategies in tandem could increase HIV detection and promote linkage to care. We aimed to assess an intervention to improve HIV detection within socio-sexual networks of PLWH in two sexually transmitted infections (STI) clinics in Lilongwe, Malawi.
METHODS: We conducted a randomized controlled trial to evaluate an intervention combining acute HIV infection (AHI) screening, contract partner notification and social contact referral versus the Malawian standard of care: serial rapid serological HIV tests and passive partner referral. Enrolment occurred between 2015 and 2019. HIV-seropositive persons (two positive rapid tests) were randomized to the trial arms and HIV-seronegative (one negative rapid test) and -serodiscordant (one positive test followed by a negative confirmatory test) persons were screened for AHI with HIV RNA testing. Those found to have AHI were offered enrolment into the intervention arm. Our primary outcome of interest was the number of new HIV diagnoses made per index participant within participants' sexual and social networks. We also calculated total persons, sexual partners and PLWH (including those previously diagnosed) referred per index participant.
RESULTS: A total of 1230 HIV-seropositive persons were randomized to the control arm, and 561 to the intervention arm. Another 12,713 HIV-seronegative or -serodiscordant persons underwent AHI screening, resulting in 136 AHI cases, of whom 94 enrolled into the intervention arm. The intervention increased the number of new HIV diagnoses made per index participant versus the control (ratio: 1.9; 95% confidence interval (CI): 1.2 to 3.1). The intervention also increased the numbers of persons (ratio: 2.5; 95% CI: 2.0 to 3.2), sexual partners (ratio: 1.7; 95% CI: 1.4 to 2.0) and PLWH (ratio: 2.3; 95% CI: 1.7 to 3.2) referred per index participant.
CONCLUSIONS: Combining three distinct HIV testing and referral strategies increased the detection of previously undiagnosed HIV infections within the socio-sexual networks of PLWH seeking STI care. Combination HIV detection strategies that leverage AHI screening and socio-sexual contact networks offer a novel and efficacious approach to increasing HIV status awareness.
BACKGROUND: Assisted partner notification (PN) is an effective approach for increasing HIV testing among heterosexual partners. There is sparse evidence on its effect among sexual partners of men who have sex with men (MSM).
METHODS: A randomized controlled trial was conducted to compare the effect of assisted PN and passive PN interventions on uptake of HIV testing among male and female sexual partners of newly HIV-diagnosed MSM. In the passive PN group, participants were encouraged to disclose their HIV status and refer and persuade sexual partners to access HIV testing services (HTS). In the assisted PN group, participants were further provided with HIV self-testing kits for sexual partners to take a test at home or allow a community health worker from MSM-serving community-based organization (CBO) to anonymously refer and persuade their sexual partners to access HTS. The primary outcome was the proportion of index cases who had any sexual partner accessing HTS within four months after randomization. This trial is registered with chictr.org.cn, ChiCTR1800017813.
FINDINGS: Between August 2017 and January 2019, 187 MSM newly diagnosed with HIV in a large city Shenyang in northern China were enrolled in the study and randomly assigned to either passive PN (n=90) or assisted PN (n=97) study groups. The proportion of index cases who disclosed their HIV status to any sexual partners within three months of randomization was similar between passive PN (57%, 95% confidence interval [CI]: 46-67%) and assisted PN groups (58%, 95% CI: 48-68%). During four months of follow-up, the number of sexual partners named, referred to HTS, tested and testing positive per index case was 3•2, 0•7, 0•2 and 0•03 in the passive PN group, and 4•0, 1•0, 0•5 and 0•10 in the assisted PN group. Thirty-five percent of index cases in the assisted PN group had any sexual partners accessing HIV testing compared to 17% in the passive PN group (P = 0•004); 49% sexual partners who were disclosed by index cases in the assisted PN group had access HTS compared to 28% in the passive PN group (P = 0•007).
INTERPRETATION: The assisted PN strategy incorporating HIV self-testing and CBO outreach can increase uptake of HIV testing among sexual partners of MSM who were recently diagnosed with HIV.
FUNDING: National Science and Technology Major Project of China, National Natural Science Foundation of China, and Project for Overseas Visiting Research of Liaoning Province.
This study compared the yield of tuberculosis (TB) active case finding (ACF) interventions applied under TB REACH funding. Between June 2017 to November 2018, Birat Nepal Medical Trust identified presumptive cases using simple verbal screening from three interventions: door-to-door screening of social contacts of known index cases, TB camps in remote areas, and screening for hospital out-patient department (OPD) attendees. Symptomatic individuals were then tested using smear microscopy or GeneXpert MTB/RIF as first diagnostic test. Yield rates were compared for each intervention and diagnostic method. We evaluated additional cases notified from ACF interventions by comparing case notifications of the intervention and control districts using standard TB REACH methodology. The project identified 1092 TB cases. The highest yield was obtained from OPD screening at hospitals (n = 566/1092; 52%). The proportion of positive tests using GeneXpert (5.5%, n = 859/15,637) was significantly higher than from microscopy testing 2% (n = 120/6309). (OR = 1.4; 95%CI = 1.12-1.72; p = 0.0026). The project achieved 29% additionality in case notifications in the intervention districts demonstrating that GeneXpert achieved substantially higher case-finding yields. Therefore, to increase national case notification for TB, Nepal should integrate OPD screening using GeneXpert testing in every district hospital and scale up of community-based ACF of TB patient contacts nationally.
Responding to measles outbreaks in the United States puts a considerable strain on public health resources, and limited research exists about the effectiveness of containment strategies. In this paper we quantify the impact of isolation, contact tracing, and exclusion in reducing transmission during a measles outbreak in an under-vaccinated community.
