The HPV-Automated Visual Evaluation (PAVE) Consortium is validating a cervical screening strategy enabling accurate cervical screening in resource-limited settings. A rapid, low-cost HPV assay permits sensitive HPV testing of self-collected vaginal specimens; HPV-negative women are reassured. Triage of positives combines HPV genotyping (four groups in order of cancer risk) and visual inspection assisted by automated cervical visual evaluation (AVE) that classifies cervical appearance as severe, indeterminate, or normal. Together, the combination predicts which women have precancer, permitting targeted management to those most needing treatment.
We analyzed CIN3+ yield for each PAVE risk level (HPV genotype crossed by AVE classification) from nine clinical sites (Brazil, Cambodia, Dominican Republic, El Salvador, Eswatini, Honduras, Malawi, Nigeria, and Tanzania). Data from 1832 HPV-positive participants confirmed that HPV genotype and AVE classification each strongly and independently predict risk of histologic CIN3+. The combination of these low-cost tests provided excellent risk stratification, warranting pre-implementation demonstration projects.
BACKGROUND
In settings with low pneumococcal conjugate vaccine (PCV) coverage, multi-age cohort mass campaigns could increase population immunity, and fractional dosing could increase affordability. We aimed to evaluate the effect of mass campaigns on nasopharyngeal pneumococcal carriage of Pneumosil (PCV10) in children aged 1-9 years in Niger.
METHODS
In this three-arm, open-label, cluster-randomised trial, 63 clusters of one to four villages in Niger were randomly assigned (3:3:1) using block randomisation to receive campaigns consisting of a single full dose of a 10-valent PCV (Pneumosil), a single one-fifth dose of Pneumosil, or no campaign. Independently sampled carriage surveys were done among 2268 households 6 months before and after vaccination, collecting nasopharyngeal swabs from healthy children for culture and serotyping; those with contraindication to nasopharyngeal swabbing were excluded. The primary outcome was nasopharyngeal carriage of vaccine-serotype pneumococcus. We tested whether vaccine-type carriage was reduced in full-dose versus control clusters; and whether fractional doses were non-inferior to full-doses (lower bound 95% CI more than -7·5%), using generalised estimating equations to analyse cluster summaries at baseline and follow-up, controlling for covariates to estimate risk differences and their 95% CIs. The study is registered with ClinicalTrials.gov (NCT05175014) and the Pan-African Clinical Trials Registry (PACTR20211257448484).
FINDINGS
Surveys were done between Dec 22, 2021, and March 18, 2022, and between Dec 12, 2022, and March 9, 2023. The vaccination campaign ran from June 15 to Aug 2, 2022. Participants' characteristics were consistent across surveys and groups. Pre-vaccination, vaccine-type carriage was 15·6% (149 of 955 participants) in the full-dose group, 17·9% (170 of 948) in the fractional-dose group, and 18·8% (60 of 320) in the control group. Post-vaccination, vaccine-type carriage was 4·6% (44 of 967) in the full-dose group, 8·0% (77 of 962) in the fractional-dose group, and 16·5% (53 of 321) in the control group. The primary analysis showed a risk difference of -16·2% (95% CI -28·6 to -3·0) between the full-dose group and control group (p=0·002 for superiority), and -3·8% (-6·1 to -1·6) between the full-dose group and fractional-dose group, meeting the non-inferiority criteria. No adverse events were judged to be related to vaccination.
INTERPRETATION
Multi-age cohort campaigns had a marked effect on vaccine-type carriage and fractional-dose campaigns met non-inferiority criteria. Such campaigns should be considered in low-coverage settings, including humanitarian emergencies, to accelerate population protection.
INTRODUCTION
The health systems of countries in the South and the North have been directly affected by the COVID-19 pandemic. Healthcare workers have paid a high price. The aim of this study was to better describe the personnel who are on the front line when patients visit health care facilities and to analyze their risk factors for exposure, their perception of infection and the prevention practices implemented by these health care workers.
METHODS
A cross-sectional study was conducted over a 6-month period from October 2021 to March 2022 (i.e., at a distance from the index cases) among health care workers in 62 integrated health centers and five public urban hospitals in Niamey and Dosso. Information on socio-demographic characteristics, clinical symptoms, co-morbidities, knowledge and attitudes, and vaccination status was collected by means of a questionnaire. Blood samples were taken for serological analysis for each agent included.
RESULTS
A total of 733 agents were included, mostly women (628, 85.67%) with a mean age of 40.5 years. Only 5.5% (40/733) of the workers reported having been in contact with a positive case of Covid-19. The most common method of protection was the use of alcohol and soap for hand hygiene. 76% of them reported having been vaccinated against the SARS-CoV2 virus. However, only 7.7% reported having used a Covid-19 diagnostic test in the last few months. IgM and IgG COVID-19 serologies were positive in 1.2% and 92.2% of the health care workers, respectively, during the survey period.
CONCLUSION
In Niger, frontline health workers have been widely exposed to SARS CoV-2, but most of them don't think so. As a result, in their daily practice, they make poor use of means to prevent and control COVID-19 infection and rarely use diagnostic tests in case of illness. Vaccination was widely accepted by these staff, according to their statements.
Outbreak alert systems can offset the severity of measles epidemics by minimising response delays. Existing systems, however, are often too sensitive to be practical when identifying areas for reactive interventions. To redress this challenge, we present a simple alternative system that combines a weekly and triweekly suspected case threshold. First evaluated in the DRC in 2022, here we extend the evaluation of this system to the context of Niger.
METHODS
A large number of threshold combinations were evaluated against indicators of cases captured by intervention and false alert risk. Combinations were evaluated against admin 2 level surveillance data from the DRC and Niger from 2015-2024. Performance was then compared to standard recommendations from the WHO and MSF.
RESULTS
The two example countries have distinct epidemic profiles, with the DRC exhibiting mas epidemics and Niger showing strong annual seasonality. In both settings, the proposed alternative alert system outperformed the existing WHO and MSF recommendation. The WHO recommendation, which is triggered by four suspected cases occuring within one month in a given locale (here, admin level 2), performs similarly to the proposed alternative when selecting the most sensitive of threshold combinations. The MSF recommendation, which is triggered by a raw increase in number of cases for three consecutive weeks, performed markedly worse, capturing 50% or less of cases. This poor performance is predominantly attributable to the high volatility of weekly measles surveillance data.
CONCLUSION
This analysis presents a simple evidence based alert system to improve measles outbreak response. It has been assessed in two countries, Niger and the DRC, and found to outperform standard recommendations. At present the system is available for use in both countries via their respective surveillance dashboards. Ongoing work is being conducted to evaluate the system in settings with additional epidemic profiles, including areas with low burden and areas with poor surveillance.
BACKGROUND
In settings with low Pneumoccocal Conjugate Vaccine (PCV) coverage, mass campaigns targeting multi-age cohorts (MAC) might accelerate herd protection but ould be costly. Campaigns using fractional dose PCV would decrease cost and increase access.
METHODS
We conducted a cluster-randomized trial in Niger to evaluate the effect of a mass campaign targeting children aged 1-9 years on pneumococcal carriage. 63 villages were randomized in a 3:3:1 ratio to receive campaigns with a single full dose of a 10-valent PCV (Pneumosil®), a single 1/5th fractional dose, or no campaign. We conducted two independent carriage surveys among a total of 2268 households 6 months before and 6 months after vaccination, collecting a nasopharyngeal swab from a child aged 1-9 years for culture and serotyping. If the full-dose campaign was shown superior to control in carriage reduction, the non-inferiority of fractional-dose campaign was to be evaluated, with the lower bound of the 95%CI > -7.5%. Registration: NCT05175014, PACTR20211257448484
RESULTS
Surveys were conducted between December 22, 2021, and 18 March, 2022, and December 12, 2022, and March 9, 2023. The vaccination campaign was June 15-August 2, 2022. Participant characteristics were similar between the two surveys and across arms. Pre-vaccination, vaccine-type (VT) carriage was 15.6% in the full-dose arm, 17.9% in the fractional dose arm, and 18.8% in the control arm. Post-
vaccination, VT carriage was 4.6% in the full-dose arm, 8.0% in the fractional dose arm, and 16.5% in the control arm. In the primary analysis, the risk difference between the full dose and the control arms was -12.0% [-19.0; -5.0], p=0.001, and between the full dose and fractional dose arms it was -3.5% [-5.8; -1.1], meeting the prespecified non-inferiority criterion. Similar results were seen after adjustment for age, vaccine coverage and other factors.
CONCLUSION
MAC campaigns had a marked impact on VT carriage and fractional-dose campaigns met non-inferiority criteria. Such campaigns should be considered in low-coverage settings, including humanitarian emergencies, to accelerate population protection.
Under-diagnosis of tuberculosis in children remains a major concern worldwide. The World Health Organization (WHO) recommends two new treatment decision algorithms for TB in children less than 10 years presenting with presumptive pulmonary TB. The algorithms are adapted to contexts with, and without radiography, include laboratory testing if available, and aim to facilitate treatment decision by assigning scores to symptoms and radiological features. However, little is known about the feasibility and acceptability of implementing these algorithms in Sub-Saharan Africa settings.
METHODS
Using a qualitative study design, we conducted 45 semi-structured interviews with health workers in nine health facilities in Uganda, Niger and Guinea. We analyzed the data thematically, and using the critical discourse analysis with a deductive and inductive approach to identify contextual barriers and acceptance of the intervention among health workers.
RESULTS
Firstly, discourse analysis shows that health workers identify various socio-cultural factors (e.g.: delays in children arriving at health facilities, stigmatization) and structural factors (e.g. high workload for health workers, lack of resources in the health centres) as the major barriers that make TB diagnosis difficult. In this context, implementation of the algorithms is positively perceived (e.g.: the scoring system was found to be useful and user-friendly) but raises some challenges (e.g.: additional paperwork). Otherwise, results shows that the implementation of the algorithms plays a role in strengthening health worker's sense of autonomy and efficiency, and some paramedical staff (nurses) express the wish to be more directly involved in applying the algorithms.
CONCLUSION
This study found that the new TB algorithms were perceived positively by health workers, and well accepted in the three countries. However, it illustrates the extent to which the implementation of innovative tools in healthcare structures needs to consider the existing system, potential barriers, and opportunities to ensure long-term use.