A5003461314- COVID-19 epidemiological studies
- Influenza Virus Research Studies
- Vaccine Coverage and Hesitancy
- SARS-CoV-2 and COVID-19 Research
- Respiratory viral infections research
- Virology and Viral Diseases
- Data-Driven Disease Surveillance
- Mathematical and Theoretical Epidemiology and Ecology Models
- Poxvirus research and outbreaks
- Bacillus and Francisella bacterial research
- COVID-19 and Mental Health
- COVID-19 Pandemic Impacts
- Viral gastroenteritis research and epidemiology
- Viral Infections and Outbreaks Research
- HIV/AIDS Research and Interventions
- Weed Control and Herbicide Applications
- Animal Disease Management and Epidemiology
- Hepatitis B Virus Studies
- Evolution and Genetic Dynamics
- Reproductive tract infections research
- HIV, Drug Use, Sexual Risk
- COVID-19 Clinical Research Studies
- Complex Network Analysis Techniques
- Pneumonia and Respiratory Infections
- Antibiotic Use and Resistance
National Institute for Public Health and the Environment
2016-2025
Leiden University Medical Center
2016-2025
Institute of Public Health Zadar
2021-2024
University of Hong Kong
2024
Leiden University
2006-2023
Wageningen University & Research
1994-2022
Health Forecasting
2000-2020
Eindhoven Cancer Registry
2019
Dutch Expert Centre for Screening
2018
Amsterdam UMC Location University of Amsterdam
2016
Mathematical modelling of infectious diseases transmitted by the respiratory or close-contact route (e.g., pandemic influenza) is increasingly being used to determine impact possible interventions. Although mixing patterns are known be crucial determinants for model outcome, researchers often rely on a priori contact assumptions with little no empirical basis. We conducted population-based prospective survey in eight European countries using common paper-diary methodology.7,290 participants...
A novel coronavirus (2019-nCoV) is causing an outbreak of viral pneumonia that started in Wuhan, China. Using the travel history and symptom onset 88 confirmed cases were detected outside Wuhan early phase, we estimate mean incubation period to be 6.4 days (95% credible interval: 5.6–7.7), ranging from 2.1 11.1 (2.5th 97.5th percentile). These values should help inform 2019-nCoV case definitions appropriate quarantine durations.
Mathematical models of transmission have become invaluable management tools in planning for the control emerging infectious diseases. A key variable such is reproductive number R. For new diseases, value can only be inferred indirectly from observed exponential epidemic growth rate r. Such inference ambiguous as several different equations exist that relate to rate, and it unclear which these might apply a infection. Here, we show differ with respect their assumed shape generation interval...
Severe acute respiratory syndrome (SARS) has been the first severe contagious disease to emerge in 21st century. The available epidemic curves for SARS show marked differences between affected regions with respect total number of cases and duration, even those which outbreaks started almost simultaneously similar control measures were implemented at same time. authors developed a likelihood-based estimation procedure that infers temporal pattern effective reproduction numbers from an...
The estimation of transmission parameters has been problematic for diseases that rely predominantly on pathogens from person to through small infectious droplets. Age-specific determine how such respiratory agents will spread among different age groups in a human population. Estimating the values these is essential planning an effective response potentially devastating pandemics smallpox or influenza and designing control strategies as measles mumps. In this study, authors estimated...
BackgroundEstimating key infectious disease parameters from the coronavirus (COVID-19) outbreak is essential for modelling studies and guiding intervention strategies.AimWe estimate generation interval, serial proportion of pre-symptomatic transmission effective reproduction number COVID-19. We illustrate that numbers calculated based on interval estimates can be biased.MethodsWe used data clusters in Singapore Tianjin, China to symptom onset while acknowledging uncertainty about incubation...
Estimation of the effective reproductive number Rt is important for detecting changes in disease transmission over time. During Coronavirus Disease 2019 (COVID-19) pandemic, policy makers and public health officials are using to assess effectiveness interventions inform policy. However, estimation from available data presents several challenges, with critical implications interpretation course pandemic. The purpose this document summarize these illustrate them examples synthetic data, and,...
We collated contact tracing data from COVID-19 clusters in Singapore and Tianjin, China estimated the extent of pre-symptomatic transmission by estimating incubation periods serial intervals. The mean accounting for intermediate cases were 4.91 days (95%CI 4.35, 5.69) 7.54 6.76, 8.56) respectively. interval was 4.17 2.44, 5.89) 4.31 2.91, 5.72) (Singapore, Tianjin). intervals are shorter than periods, suggesting that may occur a large proportion events (0.4–0.5 0.6–0.8 our analysis with...
Abstract Background As the COVID-19 epidemic is spreading, incoming data allows us to quantify values of key variables that determine transmission and effort required control epidemic. We incubation period serial interval distribution for clusters in Singapore Tianjin. infer basic reproduction number identify extent pre-symptomatic transmission. Methods collected outbreak information from Tianjin, China, reported Jan.19-Feb.26 Jan.21-Feb.27, respectively. estimated periods intervals both...
In May 2022, monkeypox outbreaks have been reported in countries not endemic for monkeypox. We estimated the incubation period, using exposure and symptom-onset times 18 cases detected confirmed Netherlands up to 31 2022. Mean period was 9.0 days* (5th–95th percentiles: 4.2–17.3), underpinning current recommendation monitor or isolate/quarantine case contacts 21 days. However, as may differ between different transmission routes, further epidemiological investigations are needed.
The SARS-CoV-2 Omicron variant has a growth advantage over the Delta because of higher transmissibility, immune evasion or shorter serial interval. Using S gene target failure (SGTF) as indication for BA.1, we identified 908 SGTF and 1,621 non-SGTF intervals in same period. Within households, mean interval cases was 0.2-0.6 days than cases. This suggests that is partly due to
In early May 2022, a global outbreak of mpox started among persons without travel history to regions known be enzootic for monkeypox virus (MPXV). On 8 August the Netherlands reported its 1,000th case, representing cumulative incidence 55 per million population, one highest incidences worldwide. We describe characteristics first 1,000 cases in Netherlands, between 20 and within context public health response. These were predominantly men who have sex with aged 31–45 years. The vast majority...
During the coronavirus disease (COVID-19) pandemic, researchers attempted to estimate number of averted and avertible outcomes due vaccination campaigns quantify public health impact. However, estimands used in these analyses have not been previously formalized. It is also unclear how relate broader framework direct, indirect, total, overall causal effects under interference. Here, using potential outcome notation, we adjust direct accommodate outcomes. We use this interrogate commonly held...
The United States was the second country to have a major outbreak of novel influenza A/H1N1 in what has become new pandemic. Appropriate public health responses this pandemic depend part on early estimates key epidemiological parameters virus defined populations.We use likelihood-based method estimate basic reproductive number (R(0)) and serial interval using individual level U.S. data from Centers for Disease Control Prevention (CDC). We adjust missing dates illness changes case...
Transmission events are the fundamental building blocks of dynamics any infectious disease. Much about epidemiology a disease can be learned when these individual transmission known or estimated. Such estimations difficult and generally feasible only detailed epidemiological data available. The genealogy estimated from genetic sequences sampled pathogens is another rich source information on history. Optimal inference calls for combination into one joint analysis. A key difficulty that tree,...
The identification of key "driver" groups in influenza epidemics is much interest for the implementation effective public health response strategies, including vaccination programs. However, relative importance different age propagating uncertain. During a communicable disease outbreak, some may be disproportionately represented during outbreak's ascent due to increased susceptibility and/or contact rates. Such or subpopulations can identified by considering proportion cases within...
The emergence and global impact of the novel influenza A(H1N1)v highlights continuous threat to public health posed by a steady stream new unexpected infectious disease outbreaks in animals humans. Once an emerging epidemic is detected, authorities will attempt mitigate by, among other measures, reducing further spread as much possible. Scarce and/or costly control measures such vaccines, anti-infective drugs, social distancing must be allocated while epidemiological characteristics remain...
Background. The combined measles, mumps, and rubella (MMR) vaccine has been successfully administered for >20 years. Because of this, protection by maternal antibodies in infants born to vaccinated mothers might be negatively affected. Methods. A large cross-sectional serologic survey was conducted the Netherlands during 2006–2007. We compared kinetics antibody concentrations children women childbearing age highly general population with those orthodox Protestant communities that were...
Knowledge on the transmission tree of an epidemic can provide valuable insights into disease dynamics. The be reconstructed by analysing either detailed epidemiological data (e.g. contact tracing) or, if sufficient genetic diversity accumulates over course epidemic, pathogen. We present a likelihood-based framework to integrate these two types, estimating probabilities infection taking weighted averages set possible trees. test approach applying it temporal, geographical and 241 poultry...
Face masks have traditionally been used in general infection control, but their efficacy at the population level preventing transmission of influenza viruses has not studied detail. Data from published clinical studies indicate that infectivity A virus is probably very high, so may involve low doses virus. At doses, relation between dose and probability approximately linear, reduction risk proportional to exposure due particle retention mask. model was set up explore impact population-wide...
Hospital-acquired infections (HAI) are often seen as preventable incidents that result from unsafe practices or poor hospital hygiene. This however ignores the fact transmissibility is not only a property of causative organisms but also hosts who can translocate bacteria when moving between hospitals. In an epidemiological sense, hospitals become connected through patients they share. We here postulate degree connectedness crucially influences rates caused by hospital-acquired bacteria. To...
Whole-genome sequencing of pathogens from host samples becomes more and routine during infectious disease outbreaks. These data provide information on possible transmission events which can be used for further epidemiologic analyses, such as identification risk factors infectivity transmission. However, the relationship between sequence is obscured by uncertainty arising four largely unobserved processes: transmission, case observation, within-host pathogen dynamics mutation. To properly...