The rabies virus can infect a number of different animals including most notably raccoons, fox, coyotes, bats, skunks and others. The pathogenesis (disease progression) differs in each. The fact that there are animals in nature with antibodies to the virus in their body indicates that some will survive the infection. Raccoon rabies is a problem on the East coast where subdivisions of homes move into more wooded areas. Contact with rabid raccoons can occur. The general rule is that if you observe a raccoon wandering around in the middle of the day, there is a chance that it is rabid and is in the latter stages of the infection. The virus is transmitted through the bite of the infected animal's saliva. The infection in the brain causes hyper salivation in many animals. A vaccine program to decrease the number of rabid raccoons has been going for the last decade in the Southeastern states. Vaccine baited meat distributed by various means is being spread in raccoon habitats in hopes of immunizing the animals against the infection. Scientists hope to see a decrease in the number of rabid raccoons in the near future.
The cause of the decline in European honeybees known as Colony Collapse Disease (CCD) is unclear. Pesticides, mites, viruses and perhaps other chemicals may have contributed to the decline. In a recent article (Science 351:555, 2016), the authors focus on the host/vector relationship of the honeybee and a mite (Varroa destructor). The vector mite transmits a virus called deformed wing virus (DMV) to the honeybee that has been clearly linked to colony collapse. Factors driving CCD that have lead to a reemergence of DMV are thought to include human managed movement of bees, adaptation of this mite to a new host and change in the virus lethality. Future studies will need to continue to focus on how viruses spread to new hosts and adapt to new environments in light of the importance of the honeybee in pollination of agricultural crops. |
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