Epidemiological and virological factors determining dengue transmission in Sri Lanka during the COVID-19 pandemic

With the onset of the COVID-19 pandemic in early 2020 there was a drastic reduction in the number of dengue cases in Sri Lanka, with an increase towards the end of 2021. We sought to study the contribution of virological factors, human mobility, school closure and mosquito factors in affecting these changes in dengue transmission in Sri Lanka during this time. To understand the reasons for the differences in the dengue case numbers in 2020 to 2021 compared to previous years, we determined the association between the case numbers in Colombo (which has continuously reported the highest number of cases) with school closures, stringency index, changes in dengue virus (DENV) serotypes and vector densities. There was a 79.4% drop in dengue cases from 2019 to 2020 in Colombo. A significant negative correlation was seen with the number of cases and school closures (Spearman's r = -0.4732, p <0.0001) and a negative correlation, which was not significant, between the stringency index and case numbers (Spearman's r = -0.3755 p = 0.0587). There was no change in the circulating DENV serotypes with DENV2 remaining the most prevalent serotype by early 2022 (65%), similar to the frequencies observed by end of 2019. The Aedes aegypti premise and container indices showed positive but insignificant correlations with dengue case numbers (Spearman r = 0.8827, p = 0.93). Lockdown measures, especially school closures seemed to have had a significant impact on the number of dengue cases, while the vector indices had a limited effect.

Epidemiological and virological factors determining dengue transmission in Sri Lanka during the COVID-19 pandemic.

With the onset of the COVID-19 pandemic in early 2020 there was a drastic reduction in the number of dengue cases in Sri Lanka, with an increase towards the end of 2021. We sought to study the contribution of virological factors, human mobility, school closure and mosquito factors in affecting these changes in dengue transmission in Sri Lanka during this time. To understand the reasons for the differences in the dengue case numbers in 2020 to 2021 compared to previous years, we determined the association between the case numbers in Colombo (which has continuously reported the highest number of cases) with school closures, stringency index, changes in dengue virus (DENV) serotypes and vector densities. There was a 79.4% drop in dengue cases from 2019 to 2020 in Colombo. A significant negative correlation was seen with the number of cases and school closures (Spearman's r = -0.4732, p <0.0001) and a negative correlation, which was not significant, between the stringency index and case numbers (Spearman's r = -0.3755 p = 0.0587). There was no change in the circulating DENV serotypes with DENV2 remaining the most prevalent serotype by early 2022 (65%), similar to the frequencies observed by end of 2019. The Aedes aegypti premise and container indices showed positive but insignificant correlations with dengue case numbers (Spearman r = 0.8827, p = 0.93). Lockdown measures, especially school closures seemed to have had a significant impact on the number of dengue cases, while the vector indices had a limited effect.

Implementation of a coronavirus disease 2019 infection prevention and control training program in a low-middle income country.

INTRODUCTION AND AIMS: The COVID-19 pandemic poses an ongoing risk to health workers globally. This is particularly true in low- and middle-income countries (LMICs) where resource constraints, ongoing waves of infection, and limited access to vaccines disproportionately burden health systems. Thus, infection prevention and control (IPC) training for COVID-19 remains an important tool to safeguard health workers. We report on the implementation of evidence-based and role-specific COVID-19 IPC training for health workers in a hospital and public health field setting in Sri Lanka. METHODS: We describe the development of training materials, which were contextualized to local needs and targeted to different staffing categories including support staff. We describe development of role- and context-specific IPC guidelines and accompanying training materials and videos during the first year of the COVID-19 pandemic. We describe in-person training activities and an overview of session leadership and participation. RESULTS: Key to program implementation was the role of champions in facilitating the training, as well as delivery of training sessions featuring multi-media videos and role play to enhance the training experience. A total of 296 health workers participated in the training program sessions. Of these, 198 were hospital staff and 98 were from the public health workforce. Of the 296 health workers who participated in a training session, 277 completed a pre-test questionnaire and 256 completed post-test questionnaires. A significant increase in knowledge score was observed among all categories of staff who participated in training;however, support staff had the lowest pre-test knowledge on IPC practices at 71%, which improved to only 77% after the formal class. CONCLUSION: Implementing an IPC training program during a complex health emergency is a challenging, yet necessary task. Leveraging champions, offering training through multiple modalities including the use of videos and role play, as well as inclusion of all staff categories, is crucial to making training accessible.

Codevelopment of COVID-19 infection prevention and control guidelines in lower-middle-income countries: the 'SPRINT' principles.

INTRODUCTION: The COVID-19 pandemic has required the rapid development of comprehensive guidelines to direct health service organisation and delivery. However, most guidelines are based on resources found in high-income settings, with fewer examples that can be implemented in resource-constrained settings. This study describes the process of adapting and developing role-specific guidelines for comprehensive COVID-19 infection prevention and control in low-income and middle-income countries (LMICs). METHODS: We used a collaborative autoethnographic approach to explore the process of developing COVID-19 guidelines. In this approach, multiple researchers contributed their reflections, conducted joint analysis through dialogue, reflection and with consideration of experiential knowledge and multidisciplinary perspectives to identify and synthesise enablers, challenges and key lessons learnt. RESULTS: We describe the guideline development process in the Philippines and the adaptation process in Sri Lanka. We offer key enablers identified through this work, including flexible leadership that aimed to empower the team to bring their expertise to the process; shared responsibility through equitable ownership; an interdisciplinary team; and collaboration with local experts. We then elaborate on challenges including interpreting other guidelines to the country context; tensions between the ideal compared with the feasible and user-friendly; adapting and updating with evolving information; and coping with pandemic-related challenges. Based on key lessons learnt, we synthesise a novel set of principles for developing guidelines during a public health emergency. The SPRINT principles are grounded in situational awareness, prioritisation and balance, which are responsive to change, created by an interdisciplinary team navigating shared responsibility and transparency. CONCLUSIONS: Guideline development during a pandemic requires a robust and time sensitive paradigm. We summarise the learning in the 'SPRINT principles' for adapting guidelines in an epidemic context in LMICs. We emphasise that these principles must be grounded in a collaborative or codesign process and add value to existing national responses.

Immune responses to a single dose of the AZD1222/Covishield vaccine in health care workers.

Several COVID-19 vaccines have received emergency approval. Here we assess the immunogenicity of a single dose of the AZD1222 vaccine, at one month, in a cohort of health care workers (HCWs) (629 naïve and 26 previously infected). 93.4% of naïve HCWs seroconverted, irrespective of age and gender. Haemagglutination test for antibodies to the receptor binding domain (RBD), surrogate neutralization assay (sVNT) and ex vivo IFNγ ELISpot assays were carried out in a sub-cohort. ACE2 blocking antibodies (measured by sVNT) were detected in 67/69 (97.1%) of naïve HCWs. Antibody levels to the RBD of the wild-type virus were higher than to RBD of B.1.1.7, and titres to B.1.351 were very low. Ex vivo T cell responses were observed in 30.8% to 61.7% in naïve HCWs. Previously infected HCWs, developed significantly higher (p < 0.0001) ACE2 blocking antibodies and antibodies to the RBD for the variants B.1.1.7 and B.1.351. This study shows high seroconversion after one vaccine dose, but also suggests that one vaccine dose may be insufficient to protect against emerging variants.

Predictive modelling for COVID-19 outbreak control: lessons from the navy cluster in Sri Lanka.

In response to an outbreak of coronavirus disease 2019 (COVID-19) within a cluster of Navy personnel in Sri Lanka commencing from 22nd April 2020, an aggressive outbreak management program was launched by the Epidemiology Unit of the Ministry of Health. To predict the possible number of cases within the susceptible population under four social distancing scenarios, the COVID-19 Hospital Impact Model for Epidemics (CHIME) was used. With increasing social distancing, the epidemiological curve flattened, and its peak shifted to the right. The observed or actually reported number of cases was above the projected number of cases at the onset; however, subsequently, it fell below all predicted trends. Predictive modelling is a useful tool for the control of outbreaks such as COVID-19 in a closed community.