The first rabies vaccine for human use was developed in19th century.
In 2007, the World Health Organization, the World Organization for Animal Health and other institutions chose this day to jointly launch World Rabies Day to fight this infectious disease that has been raging for at least 2,500 years. (Let rabies become history together)
Calendar year theme
2007: * * * Join hands to make rabies history.
2008: Save the Children
2009: Mobilize the whole society to pay attention to rabies.
20 10: Continue to make rabies a thing of the past.
20 1 1 year: * * Together, rabies becomes history.
2012: * * * Join hands to make rabies a thing of the past.
20 13: understand rabies and beat rabies.
20 16: rabies: education, vaccination and elimination
Not necessarily crazy, not limited to the "neuropathy" of dogs.
People who have heard of rabies must know that it is a terrible disease, probably bitten by a dog. Rabies virus, as a kind of "neuropathy" with a mortality rate of 65,438+0,000%, originated from rabies virus in Rhabdoviridae. Its English name Rabies comes from Latin "madness and insanity", and its common name Lyssavirus comes from Lyssa in Greek mythology, which stands for anger, rage and madness.
Rabies has two symptoms: violence and paralysis. Violent types are often associated with people. Sick animals are easily excited, aggressive and afraid of water and wind. Paralysis symptoms are progressive muscle paralysis and somatic paralysis. Paralytic rabies is not uncommon, but it is not well known because of its high misdiagnosis rate. Studies have found that dogs infected with rabies virus are more prone to drowsiness, sluggishness and other symptoms, while infected cats are more prone to mania and aggression.
The symptoms and symptoms of rabies virus infection in wild animals are different from those in domestic animals and cats and dogs, so special attention should be paid. The appearance of symptoms may be delayed, causing the virus to fall off first and then appear after symptoms. It is recorded that bats can spread rabies virus 12 days before symptoms appear. Even people infected with rabies virus may have symptoms earlier than biting animals.
Different hosts have different rabies virus variants. In a certain geographical range, rabies virus variants have strong adaptability to hosts, and generally only exist in specific hosts. However, frequent spills enable viruses to cross species boundaries. Transmission infection refers to the phenomenon that non-natural host species are infected with rabies, which is generally the result of contact between species, only affecting a few individuals, and will end quickly with the death of infected individuals.
It is worth mentioning that rabies is found on all continents except Antarctica. Any warm-blooded animal may get rabies, and it can be transmitted to humans through infection.
Rabies virus enters human body.
Rabies virus will retrograde along the axons of neurons after entering animals. Generally, it slowly climbs to the central nervous system at a speed of 3 mm per hour and proliferates in neurons. Rabies virus does not destroy infected cells, so nerve transmission is still active. Infection only produces the lowest dose of viral substances. At the initial stage of infection, these viral substances are confined to the nervous system and will not produce a fierce humoral immune response.
After secretly occupying the brain, the "headquarters" of human beings or animals, rabies virus spreads to other body tissues including salivary glands through nerves. Rabies virus proliferates in salivary gland cells and is finally released into saliva, waiting to enter the nervous system of another animal.
The period when the virus crawls to the brain and the animal is infected but has no symptoms is called incubation period. A study in North America shows that the incubation period of dogs is between 10 and 8 months, with an average of 3-8 weeks. The incubation period of cats ranges from 2 weeks to several months, with an average of 2 months; The incubation period of bats is 3 weeks to 209 days; In the experimental environment, the incubation period of horses infected with rabies virus is 12 days, and they die after 6 days of symptoms. The average incubation period of cattle is 15 days, and they die after 4 days of symptoms. The incubation period of sheep is 10 day.
How to control this disease?
How to control such a terrible disease Historically, methods such as capturing, controlling, killing sick wild animals and birth control have been widely used to reduce the number of rabies virus hosts. At present, vaccines are mainly used to control rabies.
The variants of rabies virus generally exist only in the corresponding host. Therefore, rabies vaccine may be effective for some species and ineffective for others. Some vaccines are effective for the host, but they may cause rabies in other animals, so this vaccine cannot be used. If there are multiple hosts in an area and only one animal is controlled for rabies, it will have little impact on the overall disease management in this area. This requires virologists to continuously develop rabies vaccines suitable for local conditions.
Historically, the control of rabies often took countermeasures after the emergence of cases, lacking the mechanism to predict the outbreak of disease, and it was difficult to control and manage before the emergence of rabies.
In order to make an effective rabies management plan, the knowledge of ecology and virology of the target species is essential. For example, the rabies research on raccoon population in Ontario, Canada includes: using GPS collar to determine raccoon's home, residence, mating, movement and interaction, and determining raccoon's activity time; The activities of raccoons in summer and early autumn were revealed by marking recapture method. Based on the investigation of bait acceptance, the best time for feeding bait vaccine was determined (August and September), and it was also found that most of the bait would be eaten within 1-3 weeks. In addition, combined with the rabies case information of raccoon dogs, scientists can estimate the incubation period of rabies in raccoons; Through genetic research, the related information of rabies host species was revealed, and the transmission route of rabies virus in wild animals was found out.
Another study found that natural barriers (such as mountains and rivers) and immune barriers (vaccination to a certain extent) will also affect the effectiveness of wildlife rabies control projects. The model shows that moderate group immunization may increase rabies cases, and the effect of high group immunization will decrease with the increase of surface roughness. Low group immunization is most effective in small plots and corridors, and high group immunization is effective in all kinds of landforms. Therefore, special attention should be paid when implementing rabies immunization program: insufficient vaccination may lead to more rabies cases than doing nothing.
In the case of unknown rabies, anyone who is attacked by dogs or wild animals should be injected with rabies vaccine and immunoglobulin (if necessary) according to regulations to minimize the impact of rabies on human beings.
Finally, I'll sum it up in two sentences:
Rabies is not limited to dogs, and killing is not an effective control method. Friends who keep pets should remember to vaccinate their pets regularly according to regulations, and humans can also vaccinate.