Informing the pandemic response: the role of the WHO's COVID-19 Weekly Epidemiological Update

On 31 December 2019, the Municipal Health Commission of Wuhan, China, reported a cluster of atypical pneumonia cases. On 5 January 2020, the WHO publicly released a Disease Outbreak News (DON) report, providing information about the pneumonia cases, implemented response interventions, and WHO's risk assessment and advice on public health and social measures. Following 9 additional DON reports and 209 daily situation reports, on 17 August 2020, WHO published the first edition of the COVID-19 Weekly Epidemiological Update (WEU). On 1 September 2023, the 158th edition of the WEU was published on WHO's website, marking its final issue. Since then, the WEU has been replaced by comprehensive global epidemiological updates on COVID-19 released every 4 weeks. During the span of its publication, the webpage that hosts the WEU and the COVID-19 Operational Updates was accessed annually over 1.4 million times on average, with visits originating from more than 100 countries. This article provides an in-depth analysis of the WEU process, from data collection to publication, focusing on the scope, technical details, main features, underlying methods, impact and limitations. We also discuss WHO's experience in disseminating epidemiological information on the COVID-19 pandemic at the global level and provide recommendations for enhancing collaboration and information sharing to support future health emergency responses.

Disseminating information on acute public health events globally: experiences from the WHO's Disease Outbreak News

WHO works, on a daily basis, with countries globally to detect, prepare for and respond to acute public health events. A vital component of a health response is the dissemination of accurate, reliable and authoritative information. The Disease Outbreak News (DON) reports are a key mechanism through which WHO communicates on acute public health events to the public. The decision to produce a DON report is taken on a case-by-case basis after evaluating key criteria, and the subsequent process of producing a DON report is highly standardised to ensure the robustness of information. DON reports have been published since 1996, and up to 2022 over 3000 reports have been published. Between 2018 and 2022, the most frequently published DON reports relate to Ebola virus disease, Middle East respiratory syndrome, yellow fever, polio and cholera. The DON web page is highly visited with a readership of over 2.6 million visits per year, on average. The DON report structure has evolved over time, from a single paragraph in 1996 to a detailed report with seven sections currently. WHO regularly reviews the DON report process and structure for improvements. In the last 25 years, DON reports have played a unique role in rapidly disseminating information on acute public health events to health actors and the public globally. They have become a key information source for the global public health response to the benefit of individuals and communities.

Global public health intelligence: World Health Organization operational practices

Early warning and response are key to tackle emerging and acute public health risks globally. Therefore, the World Health Organization (WHO) has implemented a robust approach to public health intelligence (PHI) for the global detection, verification and risk assessment of acute public health threats. WHO's PHI operations are underpinned by the International Health Regulations (2005), which require that countries strengthen surveillance efforts, and assess, notify and verify events that may constitute a public health emergency of international concern (PHEIC). PHI activities at WHO are conducted systematically at WHO's headquarters and all six regional offices continuously, throughout every day of the year. We describe four interlinked steps; detection, verification, risk assessment, and reporting and dissemination. For PHI operations, a diverse and interdisciplinary workforce is needed. Overall, PHI is a key feature of the global health architecture and will only become more prominent as the world faces increasing public health threats.

Cryopreservation of Axillary Buds of Cannabis sativa L. by V-Cryoplate Droplet-Vitrification: The Critical Role of Sucrose Preculture

BACKGROUND

Cryopreservation is the only method allowing the safe and cost-effective long-term conservation of important germplasm. Recent use of the cryo-plate system has proven beneficial in further simplifying the cryopreservation protocols.

OBJECTIVE

Developing an efficient protocol for the cryopreservation of axillary buds of Cannabis sativa elite cultivars (MX and V1-20) by the V-cryoplate droplet-vitrification technique.

MATERIALS AND METHODS

Stem segments (~5 cm in length) with mature axillary buds collected from indoor-grown plants were surface sterilized and then either precultured on MS basal medium with 0.1 M sucrose (1^st step preculture) for 72 h or non-precultured. All mature axillary buds (~1 mm) were aseptically excised from stem segments and precultured for an additional 48 h on MS basal medium with sucrose (0.3 M) and 5% DMSO prior to cryopreservation (2^nd step preculture). Biomass samples of fully mature mother plants and regrown cryopreserved plants were analyzed for Δ⁹-THC and CBD content using gas chromatography-flame ionization detector (GC/FID).

RESULTS

The survival and regrowth rates of cryopreserved axillary buds of cultivar MX following this two-step preculture were 45% and 42% respectively, while those of cultivar V1-20 were 47% and 44% respectively. A direct preculture of axillary buds (2^nd step preculture) on high sucrose (0.3M sucrose) significantly decreased both the survival and regrowth levels of axillary buds of cultivar MX (5% and 3% respectively) as well as those of cultivar V1-20 (20% and 17% respectively). Δ⁹-THC and CBD content of mother plants and regrown cryopreserved plants were found to be highly comparable to each other.

CONCLUSION

The resulting plants after cryopreservation appeared normal without any callus formation or morphogenetic variation. On maturity, mother plants and re-grown cryopreserved plants were comparable in terms of Δ⁹-THC and CBD content. This report provides an efficient protocol for cryopreservation of axillary buds of Cannabis sativa cultivars which may be applicable to other important cultivars, plant parts and other related medicinal plants.