Vaccination strategies to achieve outbreak control for MPXV Clade I with a one-time mass campaign in sub-Saharan Africa: A scenario-based modelling study.

Background: Limited mpox vaccination coverage, declining cross-protection from historical smallpox vaccination campaigns, and persistent zoonotic reservoirs leave many sub-Saharan countries susceptible to mpox outbreaks. With millions of vaccine doses made available to the region since late 2024 and the absence of country-specific guidelines for allocation, estimating the country-specific impact of one-time mass vaccination strategies is necessary for ongoing outbreaks and other countries at future risk.

Methods And Findings: We adapted a next generation matrix model to project disease transmission potential for 47 sub-Saharan countries from 2025 to 2050 under four transmission scenarios with different contributions of community versus sexual contacts.

Ring vaccination and vector control as control strategies for potential yellow fever outbreak in an Asian city.

Background: Yellow Fever (YF) importation remains an active risk to Southeast Asia. This study aims to determine the effectiveness of vector control and ring vaccination as containment strategies.

Methods: We modelled a YF outbreak in Singapore over 1 year using a metapopulation vector-host spatial model to explore the impact of a potential epidemic and intervention effectiveness.

Trust in government, science, and vaccine confidence in Southeast Asia: A latent profile analysis.

Global immunization efforts have saved millions of lives, with vaccines playing a crucial role in mitigating disease transmission. However, the COVID-19 pandemic highlighted both increased vaccine uptake and rising skepticism, fueled in part by misinformation on social media. This trend extends beyond COVID-19, contributing to overall vaccine hesitancy and a resurgence of vaccine-preventable diseases.

Roles of community and sexual contacts as drivers of clade I mpox outbreaks.

Initial investigation into the emerging mpox outbreak of novel clade Ib in eastern Democratic Republic of the Congo has identified signs of sustained human-to-human transmission and epidemiological links to sexual contacts involving female sex workers (FSWs), which have not been observed in previous clade Ia outbreaks. Using mathematical models incorporating age-dependent contact patterns, we quantified the role of frequent sexual interactions as opposed to community contacts in clade Ib's dynamics and found that this additional mode of transmission could explain its increased outbreak potential compared with clade Ia. As with the globally-circulating clade IIb, transmitted predominantly among men who have sex with men, our findings reinforce the importance of protecting key population groups, specifically FSWs for clade Ib, in controlling ongoing mpox outbreaks.

Modelling the potential spread of Clade Ib MPXV in Asian cities.

Background: The ongoing 2023-2024 mpox outbreak in several African countries, driven by the novel Clade Ib strain, has resulted in imported cases being reported in Sweden, Thailand and India. The potential high transmissibility of this new strain and shifts in transmission modes may make territories in Asia, which were minimally affected by previous mpox waves, susceptible to community-wide transmission following importation. While this highlights the importance of early preparedness, current knowledge of the virus's transmission dynamics remains too limited to effectively inform policymaking and resource planning.

Is Southeast Asia and the Western Pacific ready for potential monkeypox virus outbreaks?

The new variant of the monkeypox virus (MPXV) clade Ib has recently spread to other African countries outside the Democratic Republic of the Congo (DRC), prompting the World Health Organisation to declare the outbreak as a public health emergency of international concern (PHEIC). This comes just two years after the initial PHEIC that was issued for the clade IIb outbreaks. Compared to the clade IIb outbreaks, clade Ib shows a demographic shift, including higher case fatality rates for younger individuals, indicating a possibility of additional transmission pathways through heterosexual and household contacts.

Effectiveness of different border control strategies for reducing mpox importation risk: a modelling study.

Background: The Clade Ib monkeypox virus can be more transmissible through non-sexual routes compared to the previous Clade IIb strain. With imported cases sporadically reported globally, concerns have emerged about the potential of widespread transmission in the general community after importation events. Border control measures, such as screening and quarantining of arriving travellers, may help mitigate this risk and prevent localised outbreaks in the event of global spread.

Correction: Potential public health impacts of gonorrhea vaccination programmes under declining incidences: A modeling study.

[This corrects the article DOI: 10.1371/journal.pmed.

Evaluating strategies for global respiratory pandemic control at ports: a modelling study.

Background: Heavy reliance on container shipping during the COVID-19 pandemic with lockdown implementation and air travel bans placed substantial pressure on shipping crews and ports. Long waiting times at ports, substantial economic losses and massive supply chain disruption of essential and medical goods were observed. To minimise this for future pandemic preparedness, we explore the use of quarantining and testing of crews preboarding instead of quarantining at port calls or during voyages.

Potential public health impacts of gonorrhea vaccination programmes under declining incidences: A modeling study.

Background: Gonorrhea is the second most common sexually transmitted disease notified in Singapore in 2023. Evidence suggests that the 4CMenB vaccine designed to protect against Neisseria meningitidis infection may offer partial cross-protection against gonorrhea. This generated interest in using 4CMenB for the purpose of staving gonorrhea transmission.

Modelling the impact and cost-effectiveness of upcoming Zika virus vaccines on congenital Zika syndrome.

Background: Zika virus (ZIKV) continues to circulate in Southeast Asia following the 2015-2016 global epidemic, posing an ongoing risk of importation and disease spread for Singapore, a tropical city-state in the region. The virus remains a threat to pregnant women and their fetuses due to the risk of Congenital Zika Syndrome (CZS). Vaccines currently in development offer hope for reducing ZIKV infections and CZS cases.

Characterising global risk profiles of Mpox clade Ib importation.

The novel mpox clade Ib initially identified in the Domestic Republic of Congo has spread to its multiple neighbouring countries as well as countries beyond the African continent. We characterised the global risk of importation of mpox clade Ib, highlighting the need to ramp up surveillance capacity for early detection.

The epidemiologic and economic burden of dengue in Singapore: A systematic review.

Background: Despite its well-regarded vector control program, Singapore remains susceptible to dengue epidemics. To assist evaluation of dengue interventions, we aimed to synthesize current data on the epidemiologic and economic burden of dengue in Singapore.

Methodology: We used multiple databases (PubMed, Embase, Cochrane, international/national repositories, surveillance) to search for published and gray literature (2000-2022).

Feasibility of wastewater-based detection of emergent pandemics through a global network of airports.

Wastewater-based surveillance has been put into practice during the pandemic. Persistence of SARS-CoV-2 in faeces of infected individuals, and high volume of passengers travelling by air, make it possible to detect virus from aircraft wastewater, lending itself to the potential identification of a novel pathogen prior to clinical diagnosis. In this study, we estimated the likelihood of detecting the virus through aircraft wastewater from the probabilities of air travel, viral shedding, defecation, testing sensitivity, and sampling.

The need for pre-emptive control strategies for mpox in Asia and Oceania.

Introduction: The transmission dynamics of the recent mpox outbreak highlights the lack of infrastructure available to rapidly respond to novel STI outbreaks, of which Asia and Oceania remains particularly susceptible. Here, we simulate outbreaks in this setting and propose the use of pre-emptive vaccination within the men who have sex with men (MSM) community before the arrival and establishment of the virus.

Materials And Methods: Using data driven heterogeneous sexual contact networks, we simulated outbreaks of mpox in Singapore, Hong Kong, and Sydney.

Non-linear associations between meteorological factors, ambient air pollutants and major mosquito-borne diseases in Thailand.

Background: Transmission intensity for mosquito-borne diseases are highly heterogenous and multi-factorial. Understanding risk factors associated to disease transmission allow the optimization of vector control. This study sets out to understand and compare the combined anthropogenic and environmental risk factors of four major mosquito-borne diseases, dengue, malaria, chikungunya and Japanese encephalitis in Thailand.

EpiMix: A novel method to estimate effective reproduction number.

Transmission potential of a pathogen, often quantified by the time-varying reproduction number , provides the current pace of infection for a disease and indicates whether an emerging epidemic is under control. In this study, we proposed a novel method, EpiMix, for estimation, wherein we incorporated the impacts of exogenous factors and random effects under a Bayesian regression framework. Using Integrated Nested Laplace Approximation, EpiMix is able to efficiently generate reliable, deterministic estimates.

Use of Bluetooth contact tracing technology to model COVID-19 quarantine policies in high-risk closed populations.

Containment measures in high-risk closed settings, like migrant worker (MW) dormitories, are critical for mitigating emerging infectious disease outbreaks and protecting potentially vulnerable populations in outbreaks such as coronavirus disease 2019 (COVID-19). The direct impact of social distancing measures can be assessed through wearable contact tracing devices. Here, we developed an individual-based model using data collected through a Bluetooth wearable device that collected 33.

Association between ambient air pollutants and upper respiratory tract infection and pneumonia disease burden in Thailand from 2000 to 2022: a high frequency ecological analysis.

Background: A pertinent risk factor of upper respiratory tract infections (URTIs) and pneumonia is the exposure to major ambient air pollutants, with short term exposures to different air pollutants being shown to exacerbate several respiratory conditions.

Methods: Here, using disease surveillance data comprising of reported disease case counts at the province level, high frequency ambient air pollutant and climate data in Thailand, we delineated the association between ambient air pollution and URTI/Pneumonia burden in Thailand from 2000 - 2022. We developed mixed-data sampling methods and estimation strategies to account for the high frequency nature of ambient air pollutant concentration data.

Border Control for Infectious Respiratory Disease Pandemics: A Modelling Study for H1N1 and Four Strains of SARS-CoV-2.

Post-pandemic economic recovery relies on border control for safe cross-border movement. Following the COVID-19 pandemic, we investigate whether effective strategies generalize across diseases and variants. For four SARS-CoV-2 variants and influenza A-H1N1, we simulated 21 strategy families of varying test types and frequencies, quantifying expected transmission risk, relative to no control, by strategy family and quarantine length.

Forecasting upper respiratory tract infection burden using high-dimensional time series data and forecast combinations.

Upper respiratory tract infections (URTIs) represent a large strain on primary health resources. To mitigate URTI transmission and public health burdens, it is important to pre-empt and provide forward guidance on URTI burden, while taking into account various facets which influence URTI transmission. This is so that appropriate public health measures can be taken to mitigate strain on primary care resources.

Features of the urban environment associated with Aedes aegypti abundance in high-rise public apartments in Singapore: An environmental case-control study.

Aedes aegypti abundance in residential estates is hypothesized to contribute to localised outbreaks of dengue in Singapore. Knowing the factors in the urban environment underlying high Ae. aegypti abundance could guide intervention efforts to reduce Ae.

The impact of earlier reopening to travel in the Western Pacific on SARS-CoV-2 transmission.

Background: The COVID-19 pandemic has led to a fall of over 70% in international travel, resulting in substantial economic damages. The impact is especially pronounced in the Asia-Pacific region, where governments have been slow to relax border restrictions.

Methods: A retrospective approach was used to construct notional epidemic trajectories for eight Asia-Pacific countries or regions, from June to November 2021, under hypothetical scenarios of earlier resumption of international travel and selective border reopening.

Estimating transmission dynamics of SARS-CoV-2 at different intraspatial levels in an institutional outbreak.

Introduction: Large, localised outbreaks of COVID-19 have been repeatedly reported in high-density residential institutions. Understanding the transmission dynamics will inform outbreak response and the design of living environments that are more resilient to future outbreaks.

Methods: We developed an individual-based, multilevel transmission dynamics model using case, serology and symptom data from a 60-day cluster randomised trial of prophylaxes in a densely populated foreign worker dormitory in Singapore.

EpiRegress: A Method to Estimate and Predict the Time-Varying Effective Reproduction Number.

The time-varying reproduction (Rt) provides a real-time estimate of pathogen transmissibility and may be influenced by exogenous factors such as mobility and mitigation measures which are not directly related to epidemiology parameters and observations. Meanwhile, evaluating the impacts of these factors is vital for policy makers to propose and adjust containment strategies. Here, we developed a Bayesian regression framework, EpiRegress, to provide Rt estimates and assess impacts of diverse factors on virus transmission, utilising daily case counts, mobility, and policy data.