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 Since then, the WEU has been replaced by comprehensive global epidemiological updates on COVID-19 released every 4 weeks.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.

Surveillance for variants of SARS-CoV-2 to inform risk assessments

Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic, numerous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have emerged, some leading to large increases in infections, hospitalizations and deaths globally. The virus's impact on public health depends on many factors, including the emergence of new viral variants and their global spread. Consequently, the early detection and surveillance of variants and characterization of their clinical effects are vital for assessing their health risk. The unprecedented capacity for viral genomic sequencing and data sharing built globally during the pandemic has enabled new variants to be rapidly detected and assessed. This article describes the main variants circulating globally between January 2020 and June 2023, the genetic features driving variant evolution, and the epidemiological impact of these variants across countries and regions. Second, we report how integrating genetic variant surveillance with epidemiological data and event-based surveillance, through a network of World Health Organization partners, supported risk assessment and helped provide guidance on pandemic responses. In addition, given the evolutionary characteristics of circulating variants and the immune status of populations, we propose future directions for the sustainable genomic surveillance of SARS-CoV-2 variants, both nationally and internationally: (i) optimizing variant surveillance by including environmental monitoring; (ii) coordinating laboratory assessment of variant evolution and phenotype; (iii) linking data on circulating variants with clinical data; and (iv) expanding genomic surveillance to additional pathogens. Experience during the COVID-19 pandemic has shown that genomic surveillance of pathogens can provide essential, timely and evidence-based information for public health decision-making.

COVID-19 Mortality and Progress Toward Vaccinating Older Adults - World Health Organization, Worldwide, 2020-2022

After the emergence of SARS-CoV-2 in late 2019, transmission expanded globally, and on January 30, 2020, COVID-19 was declared a public health emergency of international concern.* Analysis of the early Wuhan, China outbreak (1), subsequently confirmed by multiple other studies (2,3), found that 80% of deaths occurred among persons aged ≥60 years. In anticipation of the time needed for the global vaccine supply to meet all needs, the World Health Organization (WHO) published the Strategic Advisory Group of Experts on Immunization (SAGE) Values Framework and a roadmap for prioritizing use of COVID-19 vaccines in late 2020 (4,5), followed by a strategy brief to outline urgent actions in October 2021.^† WHO described the general principles, objectives, and priorities needed to support country planning of vaccine rollout to minimize severe disease and death. A July 2022 update to the strategy brief^§ prioritized vaccination of populations at increased risk, including older adults,^¶ with the goal of 100% coverage with a complete COVID-19 vaccination series** for at-risk populations. Using available public data on COVID-19 mortality (reported deaths and model estimates) for 2020 and 2021 and the most recent reported COVID-19 vaccination coverage data from WHO, investigators performed descriptive analyses to examine age-specific mortality and global vaccination rollout among older adults (as defined by each country), stratified by country World Bank income status. Data quality and COVID-19 death reporting frequency varied by data source; however, persons aged ≥60 years accounted for >80% of the overall COVID-19 mortality across all income groups, with upper- and lower-middle-income countries accounting for 80% of the overall estimated excess mortality. Effective COVID-19 vaccines were authorized for use in December 2020, with global supply scaled up sufficiently to meet country needs by late 2021 (6). COVID-19 vaccines are safe and highly effective in reducing severe COVID-19, hospitalizations, and mortality (7,8); nevertheless, country-reported median completed primary series coverage among adults aged ≥60 years only reached 76% by the end of 2022, substantially below the WHO goal, especially in middle- and low-income countries. Increased efforts are needed to increase primary series and booster dose coverage among all older adults as recommended by WHO and national health authorities.

Striving towards access to essential medicines for human and animal health; a situational analysis of access to and use of antifungal medications for histoplasmosis in Ethiopia

Antifungal medications are vital in combatting fungal diseases that affect over a billion people annually. Antifungal medications for people and equids are scarce in Ethiopia, where lack of resources to treat fungal infection, in particular histoplasmosis, is a major health challenge. Histoplasmosis is endemic within the equine population in Ethiopia, where it is estimated that one in five horses are infected. This disease has far reaching impacts on equine welfare and the socio-economic wellbeing of families. The burden of histoplasmosis in people in Ethiopia is currently unknown, representing a blind spot in public health surveillance. Previous research has identified contact with wildlife, and domestic animal species as possible transmission pathways for histoplasmosis however, questions remain about the role of equids in human histoplasmosis. Given the close proximity of people and animals in this setting, the high level of endemic disease among equids, and the common sources of anti-fungals in Ethiopia, our study adopted a One-Health approach to examine how systemic issues affect access to, and use of antifungals to treat histoplasmosis among people and equids. A qualitative study was conducted in 6 urban regions of Oromia, Ethiopia in December 2018, incorporating semi-structured face-to-face interviews and focus group discussions. Twenty-seven individual interviews were held with doctors (n = 7), pharmacists (n = 12), veterinarians (n = 5), para-veterinarians (n = 2) and an equid owner (n = 1). Eleven focus groups were conducted with equid owners (n = 42), 3 with veterinarians (n = 6), 1 with para-veterinarians (n = 2) and 1 with pharmacists (n = 2). Transcripts were analysed using thematic analysis, and dimensions of key themes conceptualised and compared. Two overarching themes namely, 'Structural', and 'Human factors', summarised the main limitations to access to antifungal medications. 'Structural factors' included the national reliance on importation of medicines or pharmaceutical ingredients, inaccurate demand forecasting due to poor recording of the shortfall within the pharmaceutical supply chain, deficiencies in diagnostic capacity for fungal disease and, a healthcare system funded with a significant component of out-of-pocket expenditure. 'Human factors' that influenced access to antifungals included the perception of the expense of antifungals compared with competing needs such as food and education, the social stigma attached to histoplasmosis that could lead to delays in treatment seeking and, readily available home remedies or alternative treatment options. Furthermore, it was reported that trust in healthcare and veterinary provisions was undermined by a perceived lack of efficacious medications. Access to antifungals remains an urgent public health and animal welfare concern in Ethiopia. Key points within the supply and distribution chain that affect access to anti-fungals are identified, and policies that facilitate anti-fungal procurement and distribution should be reviewed. This paper highlights the structural, socio-economic and cultural factors influencing the management of infection with histoplasmosis, including how it is understood, identified and treated. This study identifies areas where further cross-sectorial work is needed to address these factors to improve disease control and clinical outcomes observed in human and animal histoplasmosis within Ethiopia.

Investing in preparedness for rapid detection and control of epidemics: analysis of health system reforms and their effect on 2021 Ebola virus disease epidemic response in Guinea

The 2014-2016 West Africa Ebola Virus Disease (EVD) Epidemic devastated Guinea's health system and constituted a public health emergency of international concern. Following the crisis, Guinea invested in the establishment of basic health system reforms and crucial legal instruments for strengthening national health security in line with the WHO's recommendations for ensuring better preparedness for (and, therefore, a response to) health emergencies. The investments included the scaling up of Integrated Disease Surveillance and Response; Joint External Evaluation of International Health Regulation capacities; National Action Plan for Health Security; Simulation Exercises; One Health platforms; creation of decentralised structures such as regional and prefectural Emergency Operation Centres; Risk assessment and hazard identification; Expanding human resources capacity; Early Warning Alert System and community preparedness. These investments were tested in the subsequent 2021 EVD outbreak and other epidemics. In this case, there was a timely declaration and response to the 2021 EVD epidemic, a lower-case burden and mortality rate, a shorter duration of the epidemic and a significant reduction in the cost of the response. Similarly, there was timely detection, response and containment of other epidemics including Lassa fever and Marburg virus disease. Findings suggest the utility of the preparedness activities for the early detection and efficient containment of outbreaks, which, therefore, underlines the need for all countries at risk of infectious disease epidemics to invest in similar reforms. Doing so promises to be not only cost-effective but also lifesaving.

The cost of insecurity: from flare-up to control of a major Ebola virus disease hotspot during the outbreak in the Democratic Republic of the Congo, 2019

The ongoing Ebola outbreak in the eastern Democratic Republic of the Congo is facing unprecedented levels of insecurity and violence. We evaluate the likely impact in terms of added transmissibility and cases of major security incidents in the Butembo coordination hub. We also show that despite this additional burden, an adapted response strategy involving enlarged ring vaccination around clusters of cases and enhanced community engagement managed to bring this main hotspot under control.

Public Health Program for Decreasing Risk for Ebola Virus Disease Resurgence from Survivors of the 2013-2016 Outbreak, Guinea

At the end of the 2013–2016 Ebola virus disease outbreak in Guinea, we implemented an alert system for early detection of Ebola resurgence among survivors. Survivors were asked to report health alerts in their household and provide body fluid specimens for laboratory testing. During April–September 2016, a total of 1,075 (88%) of 1,215 survivors participated in the system; follow up occurred at a median of 16 months after discharge (interquartile range 14–18 months). Of these, 784 acted as focal points and reported 1,136 alerts (including 4 deaths among survivors). A total of 372 (91%) of 408 eligible survivors had >1 semen specimen tested; of 817 semen specimens, 5 samples from 4 survivors were positive up to 512 days after discharge. No lochia (0/7) or breast milk (0/69) specimens tested positive. Our findings underscore the importance of long-term monitoring of survivors’ semen samples in an Ebola-affected country.

Ebola Virus Transmission Caused by Persistently Infected Survivors of the 2014-2016 Outbreak in West Africa

The 2014–2016 Ebola virus (EBOV) disease outbreak affected over 29000 people and left behind the biggest cohort (over 17000 individuals) of Ebola survivors in history. Although the persistence of EBOV in body fluids of survivors was reported before the recent outbreak, new evidence revealed that the virus can be detected up to 18 months in the semen, which represents the biggest risk of Ebola resurgence in affected communities. In this study, we review the knowledge on the Ebola flare-ups that occurred after the peak of the 2014–2016 Ebola epidemic in West Africa.

Epidemiology of Epidemic Ebola Virus Disease in Conakry and Surrounding Prefectures, Guinea, 2014-2015

The capital and neighboring areas remain a focal point of transmission, requiring continued public health vigilance.

In 2014, Ebola virus disease (EVD) in West Africa was first reported during March in 3 southeastern prefectures in Guinea; from there, the disease rapidly spread across West Africa. We describe the epidemiology of EVD cases reported in Guinea’s capital, Conakry, and 4 surrounding prefectures (Coyah, Dubreka, Forecariah, and Kindia), encompassing a full year of the epidemic. A total of 1,355 EVD cases, representing ≈40% of cases reported in Guinea, originated from these areas. Overall, Forecariah had the highest cumulative incidence (4× higher than that in Conakry). Case-fatality percentage ranged from 40% in Conakry to 60% in Kindia. Cumulative incidence was slightly higher among male than female residents, although incidences by prefecture and commune differed by sex. Over the course of the year, Conakry and neighboring prefectures became the EVD epicenter in Guinea.

Resurgence of Ebola Virus Disease in Guinea Linked to a Survivor With Virus Persistence in Seminal Fluid for More Than 500 Days

We report on an Ebola virus disease (EVD) survivor who showed Ebola virus in seminal fluid 531 days after onset of disease. The persisting virus was sexually transmitted in February 2016, about 470 days after onset of symptoms, and caused a new cluster of EVD in Guinea and Liberia.

Epidemiological survey of brucellosis in sheep and goats in selected pastoral and agro-pastoral lowlands of Ethiopia

An epidemiological survey was conducted in pastoral regions of Ethiopia to investigate the distribution of brucellosis in sheep and goats. Between November 2004 and December 2007, a total of 6,201 serum samples were collected from 67 randomly selected peasant associations, 25 districts and eight pastoral zones of Ethiopia. The Rose Bengal plate test (RBPT) and complement fixation test were used in series. Samples for bacteriology were collected from three export abattoirs, where 285 goats were randomly selected and tested by RBPTthree days before slaughter. Tissue samples were collected from 14 strongly positive goats and cultured in dextrose agar and Brucella agar base. To confirm and subtype the isolates, staining, biochemical tests and polymerase chain reaction were used. The overall standardised seroprevalence of brucellosis was 1.9%, ranging from 0.07% in Jijiga zone to 3.3% in Borena zone. There was statistically significant variation among the studied regions, zones, districts and peasant associations (p < 0.05). Male goats and sheep were twice as likely to test positive as females (relative risk [RRJ: 2.04; 95% confidence interval [CI]:1.7-3.4; x2 = 21.05, p < 0.05). Adults (older than 1.5 years) were three times more likely to test positive than younger animals (RR: 2.76; 95% CI: 1.14-6.73; chi2 = 5.18, p < 0.05). Goats were around four times more likely to be infected than sheep (RR: 3.8; 95% CI: 2.4-6.1; chi2 = 36.99, p < 0.05). Brucella melitensis was isolated from 2 of the 14 samples analysed. The widespread distribution of brucellosis in goats and sheep in these areas justifies the use of control measures to minimise the economic losses and public health hazards.

Catheter design for effective manual bladder irrigation

PURPOSE

We compared the efficiency of clearance of a simulated clot from a bladder model using a 6-hole irrigation catheter, a traditional Malecot catheter and a modified Malecot catheter with additional side holes.

MATERIALS AND METHODS

Latex balloons 12 inches in diameter served as the bladder model. They were filled with 300 cc Jell-O® gelatin, which had been partially solidified for 8 hours at 36F. Five manual irrigation/aspiration cycles with a 60 cc catheter tip syringe were performed to remove simulated clot from the bladder models and the amount of clot removed was measured. Five bladder models were used to test the efficiency of clot removal for each 22Fr catheter design, including a standard 22Fr Model 361222 Malecot latex 4-wing catheter (Rusch, High Wycombe, United Kingdom) and a 22Fr Bardex® Model 606118-22 latex 6-hole catheter. Two modified versions of the Malecot catheter design involving 2 and 4 additional holes were also tested to determine the effect of a hybrid 6-hole/Malecot design.

RESULTS

The 6-hole catheter was more efficient for clot evacuation than the Malecot catheter (p = 0.014). The modified Malecot catheter with 4 additional holes was more efficient than the original Malecot catheter (p = 0.020). However, it was not significantly better than the 6-hole catheter. After 5 irrigation/aspiration cycles 77.0% of residual clot remained in the bladder with the Malecot catheter compared to 60.4% and 54.0% for the 6-hole and modified 4-hole Malecot catheters, respectively.

CONCLUSIONS

The 6-hole catheter showed an advantage in clot removal over the Malecot catheter design. The enhanced ability of the 6-hole design to remove simulated clot may be attributable to the larger area covered by the holes at the catheter tip. Further investigation to determine the effect of spacing between the holes and the number of holes on the ability to break apart and remove clot is recommended for a more thorough understanding of differences among catheter models and methods of improvement.