Recruiting controls from an online panel for a case-control study enabled a timely and reliable foodborne Salmonella outbreak investigation, Germany 2021.

We explored the feasibility, suitability, and reliability of using controls recruited among members of a non-probabilistic online panel ('panel controls') in a case-control study (CCS) to investigate a Salmonella Braenderup outbreak in Germany. For comparison, another control group was recruited via random digit dialling ('classical controls'). Panel members received questionnaires by email; classical controls were interviewed by phone. Both control groups were frequency-matched to cases by age and sex; the classical controls also by federal state. Cases and controls were queried mainly about fruit consumption since melons were the suspected infection vehicle. We calculated adjusted odds ratios (aOR) and 95% confidence intervals (CIs) using single-variable and multivariable logistic regression. The study included 32 cases, 81 panel controls and 110 classical controls. Analyses identified melons, particularly Galia melons, as the most likely infection vehicle using either control group (panel controls - aOR 12, CI 2.7-66; classical controls - aOR 55, CI 8-1100). Recruitment of panel versus classical controls required substantially less person-time (8 vs. 111 hours) and was about 10 times less expensive. We recommend this timely and reliable control recruitment method when investigating diffuse foodborne outbreaks with CCS.

Key lessons learnt from COVID-19 intra-action reviews in the Republic of Moldova, Montenegro, Kosovo and North Macedonia 2020-2021: a qualitative study.

OBJECTIVES: Our study described how the WHO intra-action review (IAR) methodology was operationalised and customised in three Western Balkan countries and territories and the Republic of Moldova and analysed the common key findings to inform analyses of the lessons learnt from the pandemic response. DESIGN: We extracted data from the respective IAR reports and performed a qualitative thematic content analysis to identify common (between countries and territories) and cross-cutting (across the response pillars) themes on best practices, challenges and priority actions. The analysis involved three stages, namely: extraction of data, initial identification of emerging themes and review and definition of the themes. SETTING: IARs were conducted in the Republic of Moldova, Montenegro, Kosovo and the Republic of North Macedonia between December 2020 and November 2021. The IARs were conducted at different time points relative to the respective pandemic trajectories (14-day incidence rate ranging from 23 to 495 per 100 000). RESULTS: Case management was reviewed in all the IARs, while the infection prevention and control, surveillance and country-level coordination pillars were reviewed in three countries. The thematic content analysis identified four common and cross-cutting best practices, seven challenges and six priority recommendations. Recommendations included investing in sustainable human resources and technical capacities developed during the pandemic, providing continuous capacity-building and training (with regular simulation exercises), updating legislation, improving communication between healthcare providers at all levels of healthcare and enhancing digitalisation of health information systems. CONCLUSIONS: The IARs provided an opportunity for continuous collective reflection and learning with multisectoral engagement. They also offered an opportunity to review public health emergency preparedness and response functions in general, thereby contributing to generic health systems strengthening and resilience beyond COVID-19. However, success in strengthening the response and preparedness requires leadership and resource allocation, prioritisation and commitment by the countries and territories themselves.

Vaccine effectiveness against severe COVID-19 during the Omicron wave in Germany: results from the COViK study.

PURPOSE: COViK, a prospective hospital-based multicenter case-control study in Germany, aims to assess the effectiveness of COVID-19 vaccines against severe disease. Here, we report vaccine effectiveness (VE) against COVID-19-caused hospitalization and intensive care treatment during the Omicron wave. METHODS: We analyzed data from 276 cases with COVID-19 and 494 control patients recruited in 13 hospitals from 1 December 2021 to 5 September 2022. We calculated crude and confounder-adjusted VE estimates. RESULTS: 21% of cases (57/276) were not vaccinated, compared to 5% of controls (26/494; p < 0.001). Confounder-adjusted VE against COVID-19-caused hospitalization was 55.4% (95% CI: 12-78%), 81.5% (95% CI: 68-90%) and 95.6% (95%CI: 88-99%) after two, three and four vaccine doses, respectively. VE against hospitalization due to COVID-19 remained stable up to one year after three vaccine doses. CONCLUSION: Three vaccine doses remained highly effective in preventing severe disease and this protection was sustained; a fourth dose further increased protection.

Effectiveness of vaccines in preventing hospitalization due to COVID-19: A multicenter hospital-based case-control study, Germany, June 2021 to January 2022.

We included 852 patients in a prospectively recruiting multicenter matched case-control study in Germany to assess vaccine effectiveness (VE) in preventing COVID-19-associated hospitalization during the Delta-variant dominance. The two-dose VE was 89 % (95 % CI 84-93 %) overall, 79 % in patients with more than two comorbidities and 77 % in adults aged 60-75 years. A third dose increased the VE to more than 93 % in all patient-subgroups.

Use of a non-probabilistic online panel as a control group for case-control studies to investigate food and waterborne outbreaks in Lower Saxony, Germany.

Established methods of recruiting population controls for case-control studies in infectious disease outbreak investigations are resource- and time-intensive, and are often subject to bias. The online panel have recently gained interest as an easy and timely method to select controls. We examined the feasibility, suitability and reliability of using an online panel to select controls for case-control studies as part of investigations of diffuse food and waterborne outbreaks. In January 2019, we deployed a web survey by email to the 277 members of a non-probabilistic online panel in Lower Saxony, Germany. We questioned them on basic sociodemographic characteristics and eating habits. They were frequency matched to cases on sex and age. Their food exposures were compared to those of traditionally recruited controls of four historical case-controls studies, which successfully investigated food and waterborne outbreaks. We used logistic regressions to assess the association between the food exposures and the disease (odds ratios). The use of a control panel successfully led to the identification of the food items in three of the four historical outbreak investigations, and their recruitment benefitted from increased speed and limited costs. Timely outbreak investigations would enable rapidly implementing control measures. We recommend the further evaluation of using panellists as controls in parallel case-control studies and case-panel studies.

"If you are here at the clinic, you do not know how many people need help in the community": Perspectives of home-based HIV services from health care workers in rural KwaZulu-Natal, South Africa in the era of universal test-and-treat.

BACKGROUND: Limited engagement in clinic-based care is affecting the HIV response. We explored the field experiences and perceptions of local health care workers regarding home-based strategies as opportunities to improve the cascade of care of people living with HIV in rural South Africa as part of a Universal Test-and-Treat approach. METHODS: In Hlabisa sub-district, home-based HIV services, including rapid HIV testing and counselling, and support for linkage to and retention in clinic-based HIV care, were implemented by health care workers within the ANRS 12249 Treatment-as-Prevention (TasP) trial. From April to July 2016, we conducted a mixed-methods study among health care workers from the TasP trial and from local government clinics, using self-administrated questionnaires (n = 90 in the TasP trial, n = 56 in government clinics), semi-structured interviews (n = 13 in the TasP trial, n = 5 in government clinics) and three focus group discussions (n = 6-10 health care workers of the TasP trial per group). Descriptive statistics were used for quantitative data and qualitative data were analysed thematically. RESULTS: More than 90% of health care workers assessed home-based testing and support for linkage to care as feasible and acceptable by the population they serve. Many health care workers underlined how home visits could facilitate reaching people who had slipped through the cracks of the clinic-based health care system and encourage them to successfully access care. Health care workers however expressed concerns about the ability of home-based services to answer the HIV care needs of all community members, including people working outside their home during the day or those who fear HIV-related stigmatization. Overall, health care workers encouraged policy-makers to more formally integrate home-based services in the local health system. They promoted reshaping the disease-specific and care-oriented services towards more comprehensive goals. CONCLUSION: Because home-based services allow identification of people early during their infection and encourage them to take actions leading to viral suppression, HCWs assessed them as valuable components within the panel of UTT interventions, aiming to reach the 90-90-90 UNAIDS targets, especially in the rural Southern African region. TRIAL REGISTRATION: The registration number of the ANRS 12249 TasP trial on ClinicalTrials.gov is NCT01509508.

Comparative assessment of five trials of universal HIV testing and treatment in sub-Saharan Africa.

DESIGN: Universal voluntary HIV counselling and testing followed by prompt initiation of antiretroviral therapy (ART) for all those diagnosed HIV-infected (universal test and treat, UTT) is now a global health standard. However, its population-level impact, feasibility and cost remain unknown. Five community-based trials have been implemented in sub-Saharan Africa to measure the effects of various UTT strategies at population level: BCPP/YaTsie in Botswana, MaxART in Swaziland, HPTN 071 (PopART) in South Africa and Zambia, SEARCH in Uganda and Kenya and ANRS 12249 TasP in South Africa. This report describes and contrasts the contexts, research methodologies, intervention packages, themes explored, evolution of study designs and interventions related to each of these five UTT trials. METHODS: We conducted a comparative assessment of the five trials using data extracted from study protocols and collected during baseline studies, with additional input from study investigators. We organized differences and commonalities across the trials in five categories: trial contexts, research designs, intervention packages, trial themes and adaptations. RESULTS: All performed in the context of generalized HIV epidemics, the trials highly differ in their social, demographic, economic, political and health systems settings. They share the common aim of assessing the impact of UTT on the HIV epidemic but differ in methodological aspects such as study design and eligibility criteria for trial populations. In addition to universal ART initiation, the trials deliver a wide range of biomedical, behavioural and structural interventions as part of their UTT strategies. The five studies explore common issues, including the uptake rates of the trial services and individual health outcomes. All trials have adapted since their initiation to the evolving political, economic and public health contexts, including adopting the successive national recommendations for ART initiation. CONCLUSIONS: We found substantial commonalities but also differences between the five UTT trials in their design, conduct and multidisciplinary outputs. As empirical literature on how UTT may improve efficiency and quality of HIV care at population level is still scarce, this article provides a foundation for more collaborative research on UTT and supports evidence-based decision making for HIV care in country and internationally.

Implementing universal HIV treatment in a high HIV prevalence and rural South African setting - Field experiences and recommendations of health care providers.

BACKGROUND: We aimed to describe the field experiences and recommendations of clinic-based health care providers (HCP) regarding the implementation of universal antiretroviral therapy (ART) in rural KwaZulu-Natal, South Africa. METHODS: In Hlabisa sub-district, the local HIV programme of the Department of Health (DoH) is decentralized in 18 clinics, where ART was offered at a CD4 count ≤500 cells/µL from January 2015 to September 2016. Within the ANRS 12249 TasP trial, implemented in part of the sub-district, universal ART (no eligibility criteria) was offered in 11 mobile clinics between March 2012 and June 2016. A cross-sectional qualitative survey was conducted in April-July 2016 among clinic-based nurses and counsellors providing HIV care in the DoH and TasP trial clinics. In total, 13 individual interviews and two focus groups discussions (including 6 and 7 participants) were conducted, audio-recorded, transcribed, and thematically analyzed. RESULTS: All HCPs reported an overall good experience of delivering ART early in the course of HIV infection, with most patients willing to initiate ART before being symptomatic. Yet, HCPs underlined that not feeling sick could challenge early ART initiation and adherence, and thus highlighted the need to take time for counselling as an important component to achieve universal ART. HCPs also foresaw logistical challenges of universal ART, and were especially concerned about increasing workload and ART shortage. HCPs finally recommended the need to strengthen the existing model of care to facilitate access to ART, e.g., community-based and integrated HIV services. CONCLUSIONS: The provision of universal ART is feasible and acceptable according to HCPs in this rural South-African area. However their experiences suggest that universal ART, and more generally the 90-90-90 UNAIDS targets, will be difficult to achieve without the implementation of new models of health service delivery.