Global Outbreak Research Articles

Single-Center Survey of Prevalence of Viruses in Pediatric Liver Explants.

Adenovirus has been implicated as a cause of acute liver failure (ALF) following a global outbreak of adenovirus-associated ALF in 2021. To understand any association between viral infection and ALF, it is important to know the baseline prevalence of that virus in children undergoing liver transplant for acute and chronic liver disease (CLD). Our objective was to perform retrospective evaluation of prevalence of common hepatotropic viruses among children who underwent liver transplant at our center. We studied 33 stored frozen hepatic explant samples (originally collected between 2004 and 2021 as part of a liver repository) which fell into three categories: ALF (n = 18), acute on chronic liver failure (ACLF, n = 7), and CLD (n = 8). DNA was extracted from the samples, and viral PCR testing was performed for adenovirus, EBV, CMV, and HHV-6. Adenovirus was detected in a single case of indeterminate ALF transplanted in 2019. CMV was detected in two cases, and there were no EBV positive specimens in any group. HHV-6 was more prevalent with 21 of 33 specimens testing positive including ALF, ACLF, and CLD cases. This retrospective study of common childhood virus prevalence in liver explants provides important baseline information for studying potential viral etiologies of ALF. We did not identify any clusters of infections. The most frequently occurring virus and only virus found in all categories was HHV-6, underscoring the high prevalence in this heterogenous group. Adenovirus was identified in 1 out of 18 of ALF samples, but likely was not a hepatic pathogen.

NLRP3 inflammasome activation contributes to acute liver injury caused by CVA6 infection in mice

BackgroundCoxsackievirus (CV) A6 has emerged as an important causative agent in global outbreaks of hand, foot, and mouth disease (HFMD), which typically presents as a mild illness with a large generalized rash, herpes. However, some patients can develop encephalitis, pneumonia, myocarditis and liver injury. Our previous study took the view that CVA6 could replicate in mouse liver, leading to acute liver injury; however, the precise underlying mechanism remains elusive.Methods10-day-old wild-type (WT, C57BL/6J) and NLRP3 knock-out (KO) mice were intraperitoneal (i.p.) inoculated with a lethal dose of the CVA6 strain. The muscle homogenate supernatant from normal mice was used to inoculate mock-infected mice. At 5 days post infection (dpi), the mouse liver was taken out for histopathological analyses and molecular biology experiments.ResultsOur in vivo experiments demonstrated that CVA6 caused severe liver injury in mice, as evidenced by pathological changes in liver slices, elevated liver injury markers (e.g., AST, ALT, LDH) and pro-inflammatory cytokines (e.g., IL-6, MCP-1, TNF-α, IL-1β). Further results revealed the activation of NLRP3 inflammasome characterized by the increase in the expression of NLRP3, Cleaved-Casp-1 (p20), mature IL-1β and IL-18. Importantly, upon CVA6 infection, NLRP3 KO mice exhibited attenuated pathological damage and reduced levels of pro-inflammatory cytokines production (e.g., TNF-α and IL-1β) compared with WT mice. Finally, increased levels of blood ALT, AST, LDH were strongly correlated with the severity of CVA6 patients.ConclusionCollectively, our findings suggest that the activation of NLRP3 inflammasome is involved in CVA6 infection-induced acute liver injury, providing novel insights into CVA6 infection associated adverse clinical outcomes.

Investigating Social Capital Among COVID-19 Patients: Insights from a Cross-Sectional Study

Background: The global COVID-19 outbreak has posed significant challenges to public health. Social capital has emerged as a crucial social factor in mitigating the effects of COVID-19. Objectives: This study aimed to assess the social capital levels of patients diagnosed with COVID-19 and compare these levels between inpatient and outpatient cases. Methods: In 2021, a cross-sectional study was conducted at Ganjavaian Hospital in Dezful city, Iran, involving 428 COVID-19 patients. The participants were selected through a stratified random sampling method and divided into two groups: Inpatients and outpatients. Data were collected using a standardized social capital instrument, along with demographic information on variables such as age, gender, education level, marital status, and the severity of COVID-19 symptoms. Results: Among the COVID-19 patients, the social capital components of individual trust, cohesion/social support, and social trust/associative relations were measured at 3.24 ± 0.25, 3.15 ± 0.28, and 2.49 ± 0.41, respectively. Logistic regression analysis showed significant associations between patient status and age (OR = 1.47, CI 95%: 1.21 - 1.80), education level (OR = 2.64, CI 95%: 1.50 - 4.71), individual trust (OR = 3.40, CI 95%: 1.55 - 7.47), and cohesion/social support (OR = 3.03, CI 95%: 1.49 - 6.28). Conclusions: Outpatients demonstrated higher levels of social capital compared to inpatients, highlighting the critical role social capital plays in coping with illness. This disparity suggests that outpatients benefit from stronger social networks and support systems. Enhancing social capital for hospitalized patients could significantly improve their health outcomes.

Mpox Vaccine Hesitancy Among Brazilian Men Who Have Sex with Men: A National Cross-Sectional Study

Background: Mpox is a viral zoonosis that has gained increased attention due to a global outbreak in 2022, significantly impacting men who have sex with men (MSM). Vaccination for this disease poses a public health challenge; because it carries a strong stigma, there may be greater hesitancy in vulnerable groups. Objectives: This study aimed to determine the prevalence and factors associated with Mpox vaccine hesitancy among Brazilian MSM. Methods: A cross-sectional study was conducted between September and December 2022 using an online survey targeted at MSM. Recruitment was carried out through social media and dating apps. The sample consisted of 1449 participants and the analysis involved bivariate logistic regression. Results: The prevalence of Mpox vaccine hesitancy was 7.57%. The significant factors associated with hesitancy were primarily related to sexual practices and attitudes towards Mpox exposure and diagnosis, such as not using “glory holes” (aOR: 19.82; 95% CI: 1.60–245.69), reluctance to undergo pre- and post-exposure testing for Mpox (aOR: 9.54; 95% CI: 5.52–16.48), and not knowing close contacts diagnosed with Mpox (aOR: 4.09; 95% CI: 1.72–9.73). Participants who would not take precautions after diagnosis (aOR: 3.00; 95% CI: 1.27–7.07) and those who would not disclose their serological status (aOR: 1.93; 95% CI: 1.13–3.30) also showed a higher likelihood of vaccine hesitancy. Conclusion: Public health strategies should address these factors to expand knowledge about vaccination barriers, plan educational campaigns with targeted messaging for the MSM population, and provide inclusive healthcare environments to increase vaccine acceptance and reduce Mpox transmission in vulnerable groups.

Training for outbreak response through the Global Outbreak Alert and Response Network

Abstract The WHO designated the Information Centre for International Health Protection (INIG/ZIG 1) at the Robert Koch Institute as the first WHO Collaborating Centre for Global Outbreak Alert and Response (WHO CC GOARN). Its mandate is to aid WHO’s efforts in improving the detection of public health events and enhancing preparedness, readiness, and capabilities for alerts and rapid responses. The main focus of WHO CC GOARN at RKI include supporting WHO in the development and implementation of the GOARN training programme on international outbreak alert and response, as well as facilitating knowledge exchange and information dissemination. GOARN’s extensive engagement in international public health response underscores the need to complement technical expertise with human-centred competencies like effective communication and teamwork, while respecting diversity. On 18 -22 September 2023, WHO CC GOARN at RKI hosted the first “GOARN Outbreak Response Leadership Training Programme”, inviting 24 public health leaders plus highly experienced mentors from all WHO. The training was designed to enhance leadership mind-sets and practices, including advanced interpersonal and situational awareness, managing polarised tension, establishing trusted relationships with stakeholders, and influencing collective decision-making. Alongside expert facilitators and experienced mentors from various fields, participants engaged in open discussion, shared experiences and reflected on lessons from the COVID-19 pandemic and other recent outbreaks. This course provided an opportunity to engage with diverse, experienced and highly regarded leaders, sharing their views and personal experiences on what it means to practise leadership in health emergency response. This training also aimed to build a network of diverse, well-trained and interconnected public health leaders, upholding the principles of diversity, equity and inclusion to ensure that our response efforts resonate with the communities we serve.

Developing an mpox risk assessment matrix for social listening and infodemic insights generation

Abstract Issue Any effective response to an infodemic, requires prioritizing public health response on identified narrative themes that pose highest risk to health and well-being of populations. High-risk narratives often require more swift and far-reaching action and low-risk narratives require little or no response. Description of the problem Different countries are assigned different levels of risk to specific narratives or concerns, recognizing that for some issues there may be a large gap between the true public health threat and what is generating lots of conversations, concerns and press coverage that indicate a high degree of risk perception that may be unwarranted. WHO developed a risk matrix to apply to global analysis of questions, concerns and narratives about mpox, which resulted in biweekly infodemic intelligence reports that risk-assessed identified infodemic themes and corresponding recommendations for action. Results Risk assessment criteria were defined in the context of WHO’s global infodemic insights analysis for low, medium and high risk and positive sentiment in mpox global outbreak context before conducting the integrated analysis so that insights were reproducible and infodemic response actions were prioritized. This implemented the WHO/UNICEF training manual on 6 steps to produce an infodemic insights report, which includes tools on how to develop and apply a risk matrix for a specific public health question of concern and apply it in analysis. Lessons The approach resulted in rapid, systematic, reproducible and evidence-driven decision-making to respond to the infodemic accompanying the mpox global outbreak. Risk matrices must be adapted to the context of the public health event and the mandate of the health authority taking action. An mpox risk matrix for narratives included adaptation to reflect high-risk from stigmatizing narratives, as well as narratives circulating around or within LGBTQI+ communities. Key messages • A risk matrix must be developed and adapted to the context of each health emergency and level of health authority action. • Prioritization for rapid infodemic response based on a risk assessment is that it facilitates more effective response in a health emergency.

Optimization of PCA Error Correction Conditions to Improve Efficiency of Virus Genome De Novo Synthesis.

In recent years, there have been frequent global outbreaks of viral epidemics such as Zika, COVID-19, and monkeypox, which have had a huge impact on human health and society and have also spurred innovation in virus engineering technology. The rise of synthetic virus genome technology has provided researchers with a new platform to accelerate vaccine and drug development. Although DNA synthesis technology has made significant progress, the current virus genome synthesis technology still requires the assembly of short oligonucleotides of around 60 bp into kb-level lengths when constructing long segments, a process in which the commonly used polymerase chain reaction assembly (PCA) technology has high error rates and is cumbersome to operate. This study optimized the error correction conditions after PCA assembly, increasing the accuracy of synthesizing 1 kb DNA fragments from 4.2 ± 2.1% before error correction to 31.3 ± 3.1% after two rounds of correction, an improvement of over 6 times. This study provides a more efficient operational process for synthesizing virus genomes from scratch, indicating greater potential for virus engineering in epidemic prevention and control and the field of biomedicine.

Global genomic surveillance of monkeypox virus.

Monkeypox virus (MPXV) is endemic in Western and Central Africa and, in May 2022, a clade IIb lineage (B.1) caused a global outbreak outside Africa, resulting in its detection in 116 countries/territories. To understand the global phylogenetics of MPXV, we analysed all available MPXV sequences, including 10,670 sequences from 65 countries collected between 1958 and 2024. Our analysis reveals high mobility of clade I viruses within Central Africa, sustained human-to-human transmission of clade IIb lineage A viruses within the Eastern Mediterranean region, and distinct mutational signatures that can distinguish sustained human-to-human from animal-to-animal transmission. Moreover, distinct clade I sequences from Sudan suggest local MPXV circulation in areas of Eastern Africa over the past four decades. Our study underscores the importance of genomic surveillance in tracking spatiotemporal dynamics of MXPV clades and the need to strengthen such surveillance, including in some parts of Eastern Africa.

Genomic analysis of Salmonella Heidelberg isolated from the Brazilian poultry farms.

The rapid expansion of broiler chicken production in Brazil has presented significant sanitation challenges within the poultry industry. Among these challenges, Salmonella enterica subsp. enterica serotype Heidelberg stands as a contributor to global salmonellosis outbreaks. This study analyzed 13 draft genomes of Salmonella Heidelberg isolated from the pre-slaughter broiler chickens farms in Brazil. By conducting in silico analysis of these genomes, the study investigated genome similarity based on single nucleotide polymorphisms (SNPs) and identified genes encoding resistance to antimicrobials, sanitizers, and virulence factors. Furthermore, mobile genetic elements (MGE) were identified to assess their potential role in propagating genes through horizontal gene transfer. A risk classification was also applied based on the resistomes. The genomes revealed a high prevalence of genes conferring resistance to aminoglycosides, fosfomycin, sulfonamides, tetracycline, and genes linked to quaternary ammonium resistance. The study also uncovered six Salmonella pathogenicity islands (SPI) and over 100 genes encoding virulence factors. The association of MGE with antibiotic-resistant genes sul2 and blaCMY-2 raised concerns about the potential transfer to other bacteria, posing a substantial risk for spreading resistance mechanisms according to established risk protocols. Additionally, SNP analysis indicated close phylogenetic relationships among some isolates, suggesting a common origin. This study enhances our understanding of Salmonella Heidelberg strains by identifying key risk factors for transmission and revealing the association between resistance genes and MGEs. This insight provides a foundation for developing and implementing effective control, monitoring, and treatment strategies in the poultry industry.

The 2024 Public Health Emergency of International Concern: A Global Failure to Control Mpox.

On August 14, 2024, following a regional declaration by the Africa Centres for Disease Control and Prevention, the World Health Organization declared mpox a Public Health Emergency of International Concern, marking the second such declaration in two years. A series of outbreaks involving the more virulent clade I virus (compared to clade II, which caused a global outbreak in 2022), has now spread in 13 African countries, exposing the inadequacies of the public health infrastructure in these settings. There was significant investment during the 2022 global outbreak, but these efforts failed to address vaccine access and treatment in the Global South. Regulatory delays, unequal access to vaccines, and a lack of compassionate use treatments for severe cases have resulted in preventable cases and deaths, especially among vulnerable populations such as pregnant women, children, and the immunocompromised. The current outbreak also underscores critical knowledge gaps in our understanding of mpox, including its transmission, pathogenesis, and viral evolution. We join intensified calls for global solidarity and action to control mpox, emphasizing immediate containment measures and long-term local and international investment in African public health systems, to prevent future epidemics.

Genomic epidemiology and evolutionary dynamics of the Omicron variant of SARS-CoV-2 during the fifth wave of COVID-19 in Pakistan.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has posed extraordinary challenges to global health systems and economies. The virus's rapid evolution has resulted in several variants of concern (VOCs), including the highly transmissible Omicron variant, characterized by extensive mutations. In this study, we investigated the genetic diversity, population differentiation, and evolutionary dynamics of the Omicron VOC during the fifth wave of COVID-19 in Pakistan. A total of 954 Omicron genomes sequenced during the fifth wave of COVID-19 in Pakistan were analyzed. A Bayesian framework was employed for phylogenetic reconstructions, molecular dating, and population dynamics analysis. Using a population genomics approach, we analyzed Pakistani Omicron samples, revealing low within-population genetic diversity and significant structural variation in the spike (S) protein. Phylogenetic analysis showed that the Omicron variant in Pakistan originated from two distinct lineages, BA.1 and BA.2, which were introduced from South Africa, Thailand, Spain, and Belgium. Omicron-specific mutations, including those in the receptor-binding domain, were identified. The estimated molecular evolutionary rate was 2.562E-3 mutations per site per year (95% HPD interval: 8.8067E-4 to 4.1462E-3). Bayesian skyline plot analysis indicated a significant population expansion at the end of 2021, coinciding with the global Omicron outbreak. Comparative analysis with other VOCs showed Omicron as a highly divergent, monophyletic group, suggesting a unique evolutionary pathway. This study provides a comprehensive overview of Omicron's genetic diversity, genomic epidemiology, and evolutionary dynamics in Pakistan, emphasizing the need for global collaboration in monitoring variants and enhancing pandemic preparedness.

International external quality assessment study for detection of monkeypox virus by PCR supporting laboratory preparedness during the 2022–2023 mpox outbreak and beyond

BackgroundDiagnostic capabilities and correspondent External Quality Assessments (EQA) are key for outbreak preparedness. To support diagnostic facilities with a quality assessment of newly established monkeypox virus (MPXV) molecular diagnostic workflows, Quality Control for Molecular Diagnostics (QCMD) and the Bundeswehr Institute of Microbiology (IMB) piloted an international EQA study conducting four challenges from autumn 2022 to summer 2023 during the global mpox outbreak. ObjectivesTo assess the performance (sensitivity/specificity) of molecular assays used by diagnostic laboratories. Study designInactivated EQA panels were prepared and distributed containing seven samples of clade Ia and clade IIb MPXV strains at different viral concentrations, two specificity controls with other zoonotic orthopoxviruses (vaccinia and cowpox virus) and a negative control. Assessment was based on reported qualitative testing results. ResultsIn this outbreak-related EQA study, a total of 192 laboratories from 37 countries reported 346 qualitative datasets. Overall, core samples were correctly detected by approximately 92 % of participants in all four challenges. While sensitivity performance was acceptable in at least 90 % of datasets correctly reported even for educational MPXV-positive samples with low viral concentration [102 genome equivalents (GE)/mL], several laboratories reported the educational specificity controls as false positives or were unable to differentiate MPXV from related orthopoxviruses. ConclusionsMpox is now a globally occurring infection with a demand for quality-assured diagnostic capabilities. The newly established EQA scheme presented here, offers a multi-purpose panel for orthopoxviruses with a focus on MPXV which will continue to ensure diagnostic quality in clinical settings with up-to-date sample panels.

MPXV Infection Stimulates a More Robust and Durable Neutralizing Antibody Response Compared to MVA-BN Vaccination.

Monkeypox virus (MPXV) has recently caused a global disease outbreak in humans. Differences in the neutralizing antibody response to vaccination vs. MPXV infection remain poorly understood. Here, we examined the neutralization of MPXV and VACV by sera from a cohort of convalescent and vaccinated individuals at 1- and 8-months post-exposure. Convalescent individuals displayed higher neutralizing antibody titers against MPXV than vaccinated and MPXV-naïve persons at one-month post-exposure. Neutralizing antibody titers had waned significantly in both groups at 8 months. This study suggests additional vaccine strategies are needed to elicit a durable humoral response and prevent breakthrough infections.

Evaluation of a multiplexed immunoassay for assessing long-term humoral immunity Orthopoxviruses

BackgroundThe 2022 Monkeypox virus (MPXV) global outbreak boosted development of multiple serological assays to aid understanding of Mpox immunology. ObjectivesThe study aimed to assess a multiplexed solid-phase electrochemiluminescence immunoassay (Meso Scale Discovery (MSD)) for simultaneous detection of antibodies against MPXV, including A35, E8 and M1 antigens, along with corresponding Vaccina Virus (VACV) homologues and demonstrate its accuracy in assessing antibody titres post-vaccination and infection. MethodsAssay performance was assessed for simultaneous detection of antibodies against MPXV and corresponding VACV antigens. Sensitivity and specificity were evaluated with paediatric negatives (n = 215), pre- and post-IMVANEX vaccinated (n = 80), and MPXV (Clade IIb, n = 39) infected serum samples. ResultsThe assay demonstrated high specificity (75.68 % (CI: 69.01–81.29) - 95.98 % (CI:92.54–97.87)) and sensitivity (62.11 % (CI:52.06–71.21) - 98.59 % (CI:92.44 %–99.93 %)) depending on the Orthopoxvirus antigen. Preferential binding was observed between MPXV-infected individuals and MPXV antigens, while vaccinated individuals exhibited increased binding to VACV antigens. These results highlight differential binding patterns between antigen homologues in related viruses. ConclusionOverall, this assay demonstrates high sensitivities in detecting antibodies for multiple relevant MPXV and VACV antigens post-infection and post-vaccination, indicating its utility in understanding immune responses to Orthopoxviruses in current and future outbreaks and evaluating the immunogenicity of new-generation Mpox-specific vaccinations.

Update on Vaccine-Derived Poliovirus Outbreaks - Worldwide, January 2023-June 2024.

Circulating vaccine-derived polioviruses (cVDPVs) can emerge and lead to outbreaks of paralytic polio as well as asymptomatic transmission in communities with a high percentage of undervaccinated children. Using data from the World Health Organization Polio Information System and Global Polio Laboratory Network, this report describes global polio outbreaks due to cVDPVs during January 2023-June 2024 and updates previous reports. During the reporting period, 74 cVDPV outbreaks were detected in 39 countries or areas (countries), predominantly in Africa. Among these 74 cVDPV outbreaks, 47 (64%) were new outbreaks, detected in 30 (77%) of the 39 countries. Three countries reported cVDPV type 1 (cVDPV1) outbreaks and 38 countries reported cVDPV type 2 (cVDPV2) outbreaks; two of these countries reported cocirculating cVDPV1 and cVDPV2. In the 38 countries with cVDPV2 transmission, 70 distinct outbreaks were reported. In 15 countries, cVDPV transmission has lasted >1 year into 2024. In Nigeria and Somalia, both countries with security-compromised areas, persistent cVDPV2 transmission has spread to neighboring countries. Delayed implementation of outbreak response campaigns and low-quality campaigns have resulted in further international spread. Countries can control cVDPV outbreaks with timely allocation of resources to implement prompt, high-quality responses after outbreak confirmation. Stopping all cVDPV transmission requires effectively increasing population immunity by overcoming barriers to reaching children.

Emergency department attendances and inpatient admissions due to mpox infection, England, 2022

ObjectivesIn 2022, a global outbreak of mpox was reported. In the UK, it predominantly affected gay, bisexual and men who have sex with men (GBMSM). The study objectives were to...

Emergence of mpox in the Eastern Mediterranean Region: Data assessment and implications for a public health response

IntroductionMonkeypox (mpox) is an illness caused by the MPX virus and endemic to certain African countries. Historically, sporadic outbreaks have occurred in some non-endemic areas. In 2022, a new variant emerged, clade IIb, causing a global outbreak sustained within sexual networks among men who have sex with men (MSM). To our knowledge, this is the first multi-country study examining mpox epidemiology and clinical features of the 2022–2023 outbreak caused by clade IIb across the Eastern Mediterranean Region (EMR). MethodsWe analyzed datasets of anonymous mpox case-based reports submitted to the World Health Organization (WHO) from May 2022 to December 2023 in the EMR to describe the cumulative incidence, demographics, transmission routes, and clinical outcomes. ResultsBy the end of 2022, 95 case reports were submitted to the WHO. The first case of mpox was reported in the United Arab Emirates on May 24, 2022. The highest number of cases were reported from Lebanon (27 confirmed cases). Most cases in the EMR were adult males (92 %), 60 % identifying as MSM, and 10 % living with HIV. Most reported symptoms were rash (95.4 %) and fever (69.6 %). No intensive care unit admissions or deaths were reported. ConclusionIn this study we investigated the epidemiology, clinical presentation, and outcomes of the mpox outbreak related to clade IIb in the EMR. We raise concerns about the accuracy and completeness of the data, given that the number of cases reported to the WHO from EMR countries appears to be significantly lower than the number of cases documented within the region. This discrepancy could impact the reliability of the reported figures and the region's response strategies. Despite these challenges, collaborative efforts across EMR countries have laid the groundwork for effective outbreak response, underscoring the importance of ongoing regional cooperation to enhance future preparedness strategies.

Stability and Optimality Criteria for an SVIR Epidemic Model with Numerical Simulation

The mathematical modeling of infectious diseases plays a vital role in understanding and predicting disease transmission, as underscored by recent global outbreaks; to delve deep into the dynamic of infectious disease considering latent period presciently is inevitable as it bridges the gap between realistic nature and mathematical modeling. This study extended the classical Susceptible–Infected–Recovered (SIR) model by incorporating vaccination strategies during incubation. We introduced multiple time delays to an account incubation period to capture realistic disease dynamics better. The model is formulated as a system of delay differential equations that describe the transmission dynamics of diseases such as polio or COVID-19, or diseases for which vaccination exists. Critical aspects of the study include proving the positivity of the model’s solutions, calculating the basic reproduction number (R0) using next-generation matrix theory, and identifying disease-free and endemic equilibrium points. The local stability of these equilibria is then analyzed using the Routh–Hurwitz criterion. Due to the complexity introduced by the delay components, we examine the stability by studying the roots of a fourth-degree exponential polynomial. The effects of educational campaigns and vaccination efficacy are also investigated as control measures. Furthermore, an optimization problem is formulated, based on Pontryagin’s maximum principle, to minimize the number of infections and associated intervention costs. Numerical simulations of the delay differential equations are conducted, and a modified Runge–Kutta method with delays is used to solve the optimal control problem. Finally, we present a few simulation results to illustrate the analytical findings.

Evaluation of methods for detection of Campylobacter in raw milk: A multi-country study

Raw milk is considered a high-risk source of Campylobacter due to faecal contamination from healthy cattle and farm environments, thus linking raw milk consumption to global outbreaks. Detection of Campylobacter in raw milk poses challenges due to low contamination levels and antibacterial properties of the milk. Culture-based protocols for Campylobacter detection in milk vary, mainly with regard to pH adjustment and the choice of enrichment broth.This European collaborative study was organised by the EU Reference Laboratory (EURL) for Campylobacter together with eight EU National Reference Laboratories (NRL) for Campylobacter with the purpose to evaluate methods for culture-based detection of Campylobacter in raw cow's milk. The study was divided into two parts, an interlaboratory part and an intralaboratory part, both organised around the same two protocols. The aim of protocol 1 was to evaluate the impact of pH adjustment and storage of the milk on the culturability of Campylobacter over time. Aliquots of the spiked milk were adjusted either to pH 7.0 or pH 7.6 or left unadjusted. The milk was stored up to 48 h at refrigerated temperature and Campylobacter was quantified according to ISO 10272-2 on day 0, 1 and 2. The aim of protocol 2 was to evaluate which enrichment broth, Bolton broth (BB) or Preston broth (PB), showed highest sensitivity in detection of Campylobacter. The spiked milk was enriched in BB and PB as described in ISO 10272-1:2017 or ISO 10272-1:2017/Amd1.2023. In the interlaboratory part, each milk batch was collected locally by each participating NRL/EURL and inoculated with the same Campylobacter strain. In the follow-up intralaboratory part, the EURL-Campylobacter repeated the tests in protocol 1 and 2 but used different Campylobacter strains and strains subjected to thermal stress prior to inoculation.The results show that pH adjustment of raw milk has a negligible impact on culture-based detection of Campylobacter, regardless of strain and level of environmental stress. The composition of milk and properties of the inoculated strain influence culture-based detection of Campylobacter over storage time, and strains subjected to additional stress prior to inoculation in milk are reduced in culturability much faster than the same strains prepared under normal conditions.Finally, the study showed that PB without Campylobacter growth supplement is less effective than BB in detecting Campylobacter in raw milk.

How did the depression and anxiety levels of older New Zealanders change during the COVID-19 pandemic?

ABSTRACT There has been widespread concern about the mental health impact of the global COVID-19 outbreak. Fears have been raised that depression and anxiety among older people may have increased in the pandemic, and that adverse health behaviours, such as increased alcohol use and decreased physical activity, may have contributed to the mental health decline. This study aimed to examine changes in depression, anxiety, alcohol use and physical activity scores of people aged 55 and older in New Zealand over the initial months of the pandemic. The sample included 3,171 people who responded to wave 7 (August-November 2018) and wave 8 (June-September 2020) of the Health, Work and Retirement Study. Analyses were carried out using paired t tests and multilevel mediation modelling. There was no evidence of significant changes in depression or anxiety. Alcohol use and physical activity were shown to decrease significantly, albeit to a small degree, and there was evidence of an indirect effect of time on depression via physical activity. These findings suggest a general resilience among older people 3 to 6 months into the pandemic. However, increased attention should be paid to promoting physical exercise among older people, as a means of decreasing depression risk.