Dobromir T. Dimitrov

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Many emerging and reemerging viruses, such as rabies, SARS, Marburg, and Ebola have bat populations as disease reservoirs. Understanding the spillover from bats to humans and other animals, and the associated health risks requires an analysis of the disease dynamics in bat populations. Traditional compartmental epizootic models, which are relatively easy to(More)
Viral infections are one of the leading source of mortality worldwide. The great majority of them circulate and persist in wild reservoirs and periodically spill over into humans or domestic animals. In the wild reservoirs, the progression of disease is frequently quite different from that in spillover hosts. We propose a mathematical treatment of the(More)
Circular migrations are the periodic movement of individuals between multiple locations, observed in parts of sub-Saharan Africa. Relationships between circular migrations and HIV are complex, entailing interactions between migration frequency, partnership structure, and exposure to acute HIV infection. Mathematical modeling is a useful tool for(More)
BACKGROUND To date different vaginal gel microbicides have been evaluated in phase 2b/3 trials, but none have demonstrated effectiveness for preventing HIV infection. Failure to demonstrate effectiveness however does not necessarily indicate that a product is truly inefficacious, as several sources of efficacy dilution may compromise our ability to identify(More)
Heterosexual anal intercourse confers a much greater risk of HIV transmission than vaginal intercourse, yet its contribution to heterosexual HIV epidemics has been under-researched. In this article we review the current state of knowledge of heterosexual anal intercourse practice worldwide and identify the information required to assess its role in HIV(More)
Bats are natural reservoirs of rabies. We address the maintenance of the disease in bat colonies by developing individual and population models that generate indicators of risk of rabies to bats, that provide dynamic estimates of effects of rabies on population densities, and that suggest consequences of viral exposures and infections in bats relative to(More)
OBJECTIVES To compare the potential impact of rectal (RMB), vaginal (VMB) and bi-compartment (RVMB) (applied vaginally and protective during vaginal and anal intercourse) microbicides to prevent HIV in various heterosexual populations. To understand when a RMB is as useful than a VMB for women practicing anal intercourse (AI). METHODS Mathematical model(More)
Vaginal microbicides (VMB) are currently among the few women-initiated biomedical interventions for preventing heterosexual transmission of HIV. In this paper we use a deterministic model of HIV transmission to assess the public-health benefits of a VMB intervention and evaluate its gender-specific impact over short (initial) and extended periods of time.(More)
Predator-prey systems with linear and logistic intrinsic growth rate of the prey are analyzed. The models incorporate the mutual interference between predators into the functional response which stabilizes predatorprey interactions in the system. Positive and elementary stable nonstandard (PESN) finite-difference methods, having the same qualitative(More)