Rabies: relevance, prevention, and management in travel medicine

Deoxynivalenol Mycotoxin Inhibits Rabies Virus Replication In Vitro

Rabies is a highly fatal disease, and it is vital to find effective ways to manage and control infection. There is a need for new effective antiviral drugs that are particularly effective treatments for rabies. Deoxynivalenol (DON) is known mainly for its toxicity, but at the molecular level, it can inhibit RNA and DNA replication, and there is increasing evidence that different doses of DON have a positive effect on inhibiting virus replication. Based on this, we evaluated the effect of DON on inhibiting the rabies virus in vitro. The inhibitory effect of DON on rabies virus activity was dose- and time-dependent, and 0.25 μg/mL of DON could inhibit 99% of rabies virus activity within 24 h. Furthermore, DON could inhibit the adsorption, entry, replication, and release of rabies virus but could not inactivate the virus. The inhibitory effect of DON on rabies virus may be achieved by promoting apoptosis. Our study provides a new perspective for the study of anti-rabies virus and expands the direction of action of mycotoxins.

A Perspective on Rabies in the Middle East-Beyond Neglect

Rabies is a neglected but preventable viral zoonosis that poses a substantial threat to public health. In this regard, a global program has been initiated for the elimination of human rabies caused by rabid dogs through the mass vaccination of canine populations. Geographic areas vary greatly towards attainment of this objective. For example, while dog-mediated and wildlife rabies have been largely controlled in major parts of the Americas and Western Europe, the Middle East still grapples with human rabies transmitted by unvaccinated dogs and cats. Rabies prevention and control in the Middle East is quite difficult because the region is transcontinental, encompassing portions of Africa, Asia, and Europe, while consisting of politically, culturally, and economically diverse countries that are often subject to war and unrest. Consequently, one over-riding dilemma is the misinformation or complete lack of rabies surveillance data from this area. This communication is an attempt to provide an overview of rabies in the Middle East, as a cohesive approach for the honing of disease management in each area, based on data compiled from multiple sources. In addition, the related regional transboundary movement of rabies was investigated through phylogenetic studies of available viral gene sequences. Thereafter, the epidemiological status of rabies was assessed for the region. Finally, localities were classified first by the Stepwise Approach towards Rabies Elimination framework and then categorized into four different groups based on management theme: "rabies free"; owned dog and domestic animal vaccination; community dog vaccination; and wildlife vaccination. The classification system proposed herein may serve as a baseline for future efforts. This is especially important due to the severe lack of rabies information available for the Middle East as a whole and a need for a comprehensive program focusing on the entirety of the region in light of renewed international commitment towards canine rabies elimination.

Rabies - epidemiology, pathogenesis, public health concerns and advances in diagnosis and control: a comprehensive review

Rabies is a zoonotic, fatal and progressive neurological infection caused by rabies virus of the genus Lyssavirus and family Rhabdoviridae. It affects all warm-blooded animals and the disease is prevalent throughout the world and endemic in many countries except in Islands like Australia and Antarctica. Over 60,000 peoples die every year due to rabies, while approximately 15 million people receive rabies post-exposure prophylaxis (PEP) annually. Bite of rabid animals and saliva of infected host are mainly responsible for transmission and wildlife like raccoons, skunks, bats and foxes are main reservoirs for rabies. The incubation period is highly variable from 2 weeks to 6 years (avg. 2-3 months). Though severe neurologic signs and fatal outcome, neuropathological lesions are relatively mild. Rabies virus exploits various mechanisms to evade the host immune responses. Being a major zoonosis, precise and rapid diagnosis is important for early treatment and effective prevention and control measures. Traditional rapid Seller's staining and histopathological methods are still in use for diagnosis of rabies. Direct immunofluoroscent test (dFAT) is gold standard test and most commonly recommended for diagnosis of rabies in fresh brain tissues of dogs by both OIE and WHO. Mouse inoculation test (MIT) and polymerase chain reaction (PCR) are superior and used for routine diagnosis. Vaccination with live attenuated or inactivated viruses, DNA and recombinant vaccines can be done in endemic areas. This review describes in detail about epidemiology, transmission, pathogenesis, advances in diagnosis, vaccination and therapeutic approaches along with appropriate prevention and control strategies.

Approach to the international traveler with neurological symptoms

ABSTRACT 

International travelers commonly contract illnesses while abroad, with the highest risk in those who spend extended time in developing countries. As travel to worldwide destinations becomes more accessible, neurologists should be aware of travel-related infections and noninfectious conditions presenting with neurological manifestations. Travelers may present with a myriad of neurologic symptoms, including confusion, headache, weakness and sensory symptoms. In this review, we discuss the general approach to the returning traveler with neurological symptoms and discuss the differential diagnosis of symptoms commonly encountered in practice.

Studying immunity to zoonotic diseases in the natural host - keeping it real

Zoonotic viruses that emerge from wildlife and domesticated animals pose a serious threat to human and animal health. In many instances, mouse models have improved our understanding of the human immune response to infection; however, when dealing with emerging zoonotic diseases, they may be of limited use. This is particularly the case when the model fails to reproduce the disease status that is seen in the natural reservoir, transmission species or human host. In this Review, we discuss how researchers are placing more emphasis on the study of the immune response to zoonotic infections in the natural reservoir hosts and spillover species. Such studies will not only lead to a greater understanding of how these infections induce variable disease and immune responses in distinct species but also offer important insights into the evolution of mammalian immune systems.

Central nervous system infections in travelers

International travelers commonly contract infections while abroad, many of which are primary neurological diseases or have potential neurological sequelae. The implications of these neuroinfectious diseases extend beyond the individual, since returning travelers may contribute to the spread of infection in novel areas. In this review, we discuss signs, symptoms, treatments, and prophylaxes for these infections, as well as emerging trends with regard to neuroinfectious diseases of the returning traveler.

Controlling rabies through a multidisciplinary, public health system in Trujillo, La Libertad, Peru

Rabies remains endemic in Peru. In 1983, Latin America and the Caribbean promised to eliminate canine-transmitted rabies from the continent. This led to Peru introducing a multidisciplinary public health system for controlling and managing rabies across the country. The system consists of mass canine vaccination campaigns, post exposure prophylaxis and monitoring aggressor animals for signs of rabies. The Peruvian city of Trujillo, La Libertad, is an urban area where dogs are the principal reservoir for rabies. The disease burden of rabies in Trujillo, La Libertad is currently minimal, with no rabies cases in humans for over 10 years, and only three canine cases. No human deaths due to rabies have occurred for several decades. From this it can be inferred that antirabies systems such as this do have real effects in reducing cases of human rabies at a grass roots level.