1. Disease information
Rabies is a preventable viral disease of mammals most often transmitted through bite of rabid animals , The rabies virus infects the central nervous system, ultimately causing disease in the brain and death. The early symptoms of rabies in people are similar to that of many other illnesses, including fever, headache, and general weakness or discomfort. As the disease progresses, more specific symptoms appear and may include insomnia, anxiety, confusion, slight or partial paralysis, excitation, hallucinations, agitation, hypersalivation (increase in saliva), difficulty swallowing, and hydrophobia (fear of water). Death usually occurs within days of the onset of these symptoms.
Figure 1: Rabies Virus
After coming in contact with the virus, the bitten animal may go through one or all of several stages. With most animals, the virus will spread through the nerves of the bitten animal towards the brain. The virus is relatively slow moving and the average time of incubation from exposure to brain involvement is between 3 to 8 weeks in dogs, 2 to 6 weeks in cats, and 3 to 6 weeks in people. However, incubation periods as long as 6 months in dogs and 12 months in people have been reported. After the virus reaches the brain it then will move to the salivary glands where it can be spread through a bite. After the virus reaches the brain the animal will show one, two, or all of the three different phases.
1. Prodromal phase
The first is the prodromal phase and usually lasts for 2-3 days in dogs. Apprehension, nervousness, anxiety, solitude, and a fever may be noted. Friendly animals may become shy or irritable and may snap, whereas, aggressive animals may become affectionate and docile. Most animals will constantly lick the site of the bite. In cats, the prodromal phase lasts for only 1-2 days and they usually develop more fever spikes and erratic behavior than dogs.
2. Furious phase
From the prodromal phase, animals may enter the furious stage; cats are particularly prone to developing this phase. The furious stage of the disease in dogs usually lasts for 1 to 7 days. Animals become restless and irritable and are hyperresponsive to auditory and visual stimuli. As they become more restless, they begin to roam and become more irritable and vicious. When caged, dogs may bite and attack their enclosures. Animals progress to become disoriented and then have seizures and eventually die.
Figure 2: Signs of Rabies
3. Paralytic (dumb) phase
Animals may develop the paralytic phase either after the prodromal or furious stage. The paralytic phase usually develops within 2 to 4 days after the first signs are noted. Nerves affecting the head and throat are the first to be involved and animals may begin to salivate as a result of their inability to swallow. Deep labored breathing and a dropped jaw may result as the diaphragm and facial muscles become increasingly paralyzed. Animals may make a choking sound and many owners think that there is something lodged in the dog’s throat. The animal will get weaker and eventually go into respiratory failure and die.
All warm-blooded animals are at risk for contracting rabies, however, some species are much more resistant than others. Transmission of the virus is almost always through a bite from a rabid animal. There are a variety of different symptoms and once contracted there is no cure, and death is almost always the outcome. The disease is very preventable through vaccination. While relatively rare in humans, the risk of contracting it and the outcome of the disease make taking precautions with wild animals and vaccination of domestic ones essential.
In 2016, 614 samples are positive. In 2017, 573 samples are positive. All of data are from www.thairabies.net . We found that there are several risky area distributed around the country especially central part, North eastern part, eastern part and southern part of Thailand
Figure 3: THAI RABIES NET webpage
2. Monitoring and Surveillance
The department of livestock development has rabies surveillance plan divided into 2 parts
First, Active surveillance system
And second, passive surveillance system
The active clinical surveillance is a baseline and important component in disease surveillance that is conducted by the Provincial Livestock Officials, District Livestock Officials, Sub district Livestock Assistant and their livestock volunteers in the sub district and village level. Veterinary officers and para-veterinary officers have their routine practice or regular program to visit targeted villagers of farmers, at least once or twice a month. The veterinarian officers will collect the sample by 0.01 % of total animals or approximately 1 sample for 1 local administration for active surveillance. We will use this data for identify the status of that area.
The Passive surveillance system by collect suspected cases for confirms the disease status.
- The information of reference samples from control and operation by veterinarian institutions, or any nation coordination of rabies from reporting system from 2014-2016 are presented following the table below:
|Active surveillance sample||3587 samples||7810 samples||7885 samples||7336 samples|
|Passive surveillance sample||4383 samples||8731 samples||8424 samples||7825 samples|
3. Emergency Response
- Survey and registration of dogs: To implement dog registration campaign by www.thairabies.net and only vaccinated dogs (both owned and stray dogs) can be registered.
- Immunization: To ensure at least 80 percent of rabies immunization coverage among animal populations, and 100 percent coverage in high-risk areas (rabies incidence reported).To secure enough animals rabies vaccines by local administrative organizations, private clinic and Department of Livestock Development supplies for outbreak control and supplementary.
Figure 3: Vaccination
- Dog population control: To control and minimize stray dog populations; Dog population is about 7 million and about 10% are stray dogs. Birth control by sterilization in both male and female dogs.
- Laboratory surveillance: 8 DLD animal rabies diagnostic laboratories and Queen Saowabha Memorial Institute (QSMI) submit all samples from suspected cases.
- Outbreak management: Disease investigation conducted by human health and animal health after disease notification.
Control strategies of rabies in Thailand are consist of
1. According to the animal epidemics act B.E. 2558(2015), when cases of notifiable disease is suspected was found , the owner have to notify the DLD officials of that area within 12 hours from the time that the animals are found becoming sick or die.
2. The DLD team should verify and investigated cases in the outbreak area
3. The DLD should announce the control movement policy and quarantine zone. Moreover, the division of veterinary inspection and quarantine provided the animal quarantine station in risk area to control movement of the animals.
4. DLD provides the ring vaccination 100 % of animals within 5 km around the index cases 5. Collaboration with other units such as ministry of public health for data sharing
6. Announcement and publication to citizens about rabies information
7. Control dog and cat population
8. DLD has surveillance plan for 6 months since found the outbreak case.
- Animal shelter: To Set up and implement DLD shelters for stray dogs around the outbreak area and dogs that are abandoned by owners.