Syphilis Point of Care Rapid Test and Immediate Treatment Evaluation (SPRITE) study: a mixed-methods implementation science research protocol of eight public health units in Ontario, Canada.

Introduction: Urgent, tailored and equitable action is needed to address the alarming rise in syphilis rates in Canada. In the last decade, the rates of infectious syphilis have increased by 345% in Ontario, Canada. Underserved populations-people who use drugs, un(der)housed individuals and those living in rural and remote areas-face unique social and healthcare challenges that increase their vulnerability to syphilis infections and hinder their access to timely diagnosis and treatment.

A framework for long-lasting, slowly varying transient dynamics.

Much of the focus of applied dynamical systems is on asymptotic dynamics such as equilibria and periodic solutions. However, in many systems there are transient phenomena, such as temporary population collapses and the honeymoon period after the start of mass vaccination, that can last for a very long time and play an important role in ecological and epidemiological applications. In previous work we defined transient centers which are points in state space that give rise to arbitrarily long and arbitrarily slow transient dynamics.

The impact of infection-derived immunity on disease dynamics.

When modeling infectious diseases, it is common to assume that infection-derived immunity is either (1) non-existent or (2) perfect and lifelong. However there are many diseases in which infection-derived immunity is known to be present but imperfect. There are various ways in which infection-derived immunity can fail, which can ultimately impact the probability that an individual be reinfected by the same pathogen, as well as the long-run population-level prevalence of the pathogen.

Assessing systemic and non-systemic transmission risk of tick-borne encephalitis virus in Hungary.

Estimating the tick-borne encephalitis (TBE) infection risk under substantial uncertainties of the vector abundance, environmental condition and human-tick interaction is important for evidence-informed public health intervention strategies. Estimating this risk is computationally challenging since the data we observe, i.e.

The impact of past vaccination coverage and immunity on pertussis resurgence.

The resurgence of pertussis over the past decades has resulted in incidence levels not witnessed in the United States since the 1950s. The underlying causes have been the subject of much speculation, with particular attention paid to the shortcomings of the latest generation of vaccines. We formulated transmission models comprising competing hypotheses regarding vaccine failure and challenged them to explain 16 years of highly resolved incidence data from Massachusetts, United States.

The pertussis enigma: reconciling epidemiology, immunology and evolution.

Pertussis, a highly contagious respiratory infection, remains a public health priority despite the availability of vaccines for 70 years. Still a leading cause of mortality in developing countries, pertussis has re-emerged in several developed countries with high vaccination coverage. Resurgence of pertussis in these countries has routinely been attributed to increased awareness of the disease, imperfect vaccinal protection or high infection rates in adults.

A mathematical model for pathogen cross-contamination dynamics during produce wash.

One of the main challenges for the fresh-food produce industry is to ensure that the produce is free from harmful pathogens. A potential area of risk is due to cross-contamination in a sanitizing chlorine wash-cycle, where the same water is used to wash contaminated as well as non-contaminated produce. However, this is also an area where effective intervention strategies are possible, provided we have a good understanding of the mechanism of cross-contamination.

Avoidable errors in the modelling of outbreaks of emerging pathogens, with special reference to Ebola.

As an emergent infectious disease outbreak unfolds, public health response is reliant on information on key epidemiological quantities, such as transmission potential and serial interval. Increasingly, transmission models fit to incidence data are used to estimate these parameters and guide policy. Some widely used modelling practices lead to potentially large errors in parameter estimates and, consequently, errors in model-based forecasts.

Wave fronts in neuronal fields with nonlocal post-synaptic axonal connections and delayed nonlocal feedback connections.

We consider a neuronal network model with both axonal connections (in the form of synaptic coupling) and delayed non-local feedback connections. The kernel in the feedback channel is assumed to be a standard non-local one, while for the kernel in the synaptic coupling, four types are considered. The main concern is the existence of travelling wave front.