Current situation and control strategy of rabies in China

Tu Changchun

Military Veterinary Institute of Military Medical Sciences

Diagnostic laboratories of Ministry of Agriculture on rabies and wildlife and zoonosis

Introduction of the Lab

• Diagnostic laboratories on rabies and wildlife and zoonosis:• Established in 2005 under the approval of Ministry of Agriculture.

Carry out epidemiology survey, monitoring, diagnose, disease emergency response, technical training and consultation. Playing the role of reference laboratory in disease control.

• There are 1 academician,3 researchers, 2 associate researchers, 6 technical staffs, 10 graduate students.

Laboratory capacity building

• In accordance with the OIE and the WHO criteria, laboratory set up and master the diagnosis of rabies, formed RT-PCR and fluorescent antibody staining method for rapid virus detection, suckling mice inoculated with cell culture for virus isolation, fluorescent neutralization test for antibody monitoring as the main method of comprehensive virus detection and isolation and identification technology system, fully able to meet the need of daily epidemiological investigation, clinical diagnosis and disease emergency response, and provide the test results within 24 hours of receiving the specimen.

• sampling techniques • Fluorescence Antibody Test (FAT)• FAVN• RT-PCR• MIT• The isolation and identification of viruses• SOP• A number of independent research and development of new diagnostic techniques:

quantitative RT-PCR, test strip, ELISA, gene chips• Automatic high-throughput detection technology platform of rabies samples

Technical Training

• In 2006, 2007 held the training courses of National Rabies Prevention and Diagnosis Technique for twice under the arrangement of the Veterinary Bureau of the Ministry of Agriculture.

International Cooperation

• In 2002, set up cooperative relationship with VLA.• In 2008, OIE officially granted the sister relationship with

VLA.• Member of OIE Rabies special expert team• Participated in the 2010 International Rabies Lab

Comparison: 100% compliance of all test items

Rabies

Lyssavirus

• Rhabdoviridae;• Infect all warm-blooded animal;• Natural reservoir-dogs and wildlife;• Damage the nerve center;• Migration along the nerve fibers to the CNS,

3mm/hr;• Death rate 100%;• Transmission - bite wounds;• Resistance to the environment is not strong.

Members of LyssavirusGenus• Divided into seven genotypes, the infected usually genotype 1.

There is cross protection within types, the cross protection between types is weak.

• 1. Classical rabies virus(RABV): Genotype 1 ， Serum 1• 2. Lagos bat virus(LBV): Genotype 2 ， Serum 2• 3. Mokola virus(MOKV): Genotype 3 ， Serum 3• 4. Duvenhage virus (DUUV): Genotype 4 ， Serum 4• 5. EBLV1 （ Genotype 5 ）• 6. EBLV2 （ Genotype 6)• 7. ABLV (Genotype 7)• 8.Aravan • 9.Khujand • 10.Irkut • 11.West Caucasian bat virus

Transmission cycle of rabies

Ecological distribution of rabies virus

Distribution of rabies• Distribution of animal rabies Distribution of human rabies•

• Global human rabies: Asia: ~31000 (56% ) ， 90% in rural area• Africa: ~24000 (44%) ， 75% in rural area• Other parts of the world<500

RABIES (Situation in Asia)

• Rabies deaths in Asia ~31 000/year, the dog is the main source of transmission.

• Of which:• India: 25~30K/ year, World No.1• China:>~3K/year, World No.2

Distribution of human rabies in China

Disease burden of rabies in China

• Human:• Exposed current status:• In 2005: Annual exposure rate in Guangxi and Guizhou area: ~10%• Annual exposure rate in big city with low incidence like Beijing, • Shanghai: ~1%. i.e: Jan-June in 2006, there were 69,332 exposed • cases in Beijing.• In 2007: High incidence in rural areas , degree of exposure rate: ~ Ⅱ Ⅲ• 5.5%.

• The financial burden of post-exposure treatment:• Vaccine :250-300 yuan/person, RIG :180-1300 yuan/person,

• Theory burden: the vaccine: 18 billion (5% exposure rate, that is, 65 million people were injured);RIG :6-4.2billion (2.5% degree of exposure rate, which is 32.5 million)Ⅲ

• The actual burden: more than 10 million vaccine use each year, the cost> 3 billion.RIG useage each year

• Data from CDC

Disease burden of rabies in China

• Animal:• Burden of animal rabies control:

• Vaccine use on governmental budget• Labor cost: 10 RMB/dog• Mental pressure: danger of being bitten and risk of exposure to rabid dogs.

• vaccine shot to rural dogs is a dangerous job for countryside vets. They always fear for dog bite. Each year there are a lot countryside vets bitten by dogs when they apply vaccine immunization to the animals. There were two vets die of rabies after dog bite when they injected vaccine.

• To calculate the burden (dogs in rural areas only): dog 80 million; seedlings: 0.2 yuan/agent (live); 3 yuan/agent (dead); injection cost?

Current status of animal rabies

• Epidemiological analysis:• 1.Dog infection remains the main source of human rabies, plays the

absolute dominance of the prevalence of human rabies.• 2.Dog rabies is still mainly high degree dissemination but the the

incidence of dog bites often occurs.• 3.Still difficult to calculate the dog and other animal rabies, but since

2005, many provinces strengthened dog management and immunity.

• 4.The current decline outbreak of human rabies has fully proved the animal rabies control measure we took has achieved initial success, which added confidence for the future strengthening of animal rabies control.

Current status of animal rabies

• Monitoring:• Currently, animal rabies surveillance system is imperfect, which only

conducted very limited antibody monitoring and pathogen monitoring.

• Inadequate sources of samples• The monitor focused on the healthy animals but ignored the testing

on the infected and the incidence animals, therefore, the monitoring data is not representative, which can not reflect the real epidemic in China.

• The laboratory testing of apparently healthy carriers of the virus infection in dogs vary widely, from <1% to >20%.

• Not enough investigations on rabies virus infection in wild animals.

Current status of animal rabies

• Dog: rural dogs, not pet dogs, accounts for 95% of animal rabies

• Domestic animals: pig, sheep, cow

• Wild animals: rats, deers, bats, ferret badgers, raccoons

Surveillance of bat rabies

• Bat rabies serological survey: Samples from Guangdong (6), Yunnan (1), Guangxi (2), Hainan (1).

Surveillance of bat rabies

• Epidemiological investigation of bat rabies antibody:• Positive varieties infection：• Rousettus leschenaulti• Rhinolophus ferrumequinum• Rhinoophusblythi• Infection rate ：• Total infection ： 2.2% （ 15/685 ）• Fruit bats ： 2.3% (12/514)• Insectivorous bats ： 1.8% (3/171)• Distribution: Guangdong, Guangxi, Hainan

Current Status of Animal Rabies Control

• Ministry of Agriculture promulgated the "Rabies Control Technical Specifications ":

• Provides for the diagnosis of animal rabies, disease reporting, disease treatment, prevention measures, control and elimination of standards. It is the technical documents guide the work of the national animal rabies control.

• Regulates annual monitoring and immunization programs of animal rabies:

• Require the important provinces to launch animal rabies monitoring and immune prevention. Monitoring provides the sampling time, objects, proportion and detection methods; immunization program requirements to carry out the two large-scale dog immunization campaigns each year.

Current Status of Animal Rabies Control

• Immunization Status：• For a long time, the government pays for the rural dogs immune

vaccine, and only charge the cost of injection fees.• Various levels of dog immunity throughout the country.• Many non-epidemic provinces or cities and counties do not

immunized.• Due to lack of special funds for immunization, only some provinces

and municipalities carry out a limited dog immunization, low coverage of immunization, and dog immunization doesn’t continuously maintained.

• However, in economically developed cities such as Beijing, Guangzhou and Shenzhen, started free vaccination to the city's urban and rural dogs.

Problems in Rabies Control

The backward situation of dog raising management and animal (dog) rabies prevention and control system, is the direct cause of high human rabies.

• Backward in concepts: animal (dog) rabies awareness is not strong, strategic bias;

• Backward in management: lack of a comprehensive dog raising management;

• Backward in work: lack of routine monitoring, immunization coverage is low;

• Backward in technical support: lack of expertise and specialized laboratories.

Problems in Rabies Control• Weak awareness of Animals (dogs) rabies prevention.• Government is not paying enough attention, concept bias, leading to an unclear main

body under the epidemic prevention. Animals than to men is not heavy, not heavy weight off the dog and immune regulation of dogs, adopt a "fighting style " control, lack of sustained prevention work; Pay more attention on humans than animals, eliminate dogs than monitor and immune dogs, adopted a way of fighting to control, lack of sustained prevention work;

• Unreasonable prevention and control mechanism, lack of effective cooperation between departments.

• The government does not invest pecial funds;• Inadequate veterinary, animal rabies prevention and control has not been brought

into the veterinary priorities, lack of professional and technical personnel, few laboratory testing work carried out.

• Animal rabies prevention and control of the provinces is very uneven, not much of areas standardize the sampling and submit in a timely manner;

• People lack of understanding and do not report the disease, not willing to immune the animal, do not sent the dead animals for inspection. Difficult to carry out dog immunization in rural areas;

Problems in Rabies Control

• Lack of comprehensive management on dog breeding, in the status of anarchy.

• The city implemented registration, immunization, but the unreasonable charge fee forced large amount of dog breeding houshold go under, an alarming number of unregistered household with dogs.

• Rural areas is almost no regulation on dog breeding, in the free status.

• Results: The number of national kennel unclear, an estimated 80 million.

Problems in Rabies Control

• Deficiencies of daily monitoring on animal rabies control, low immunization coverage:

• Animal rabies epidemiology background is not accurate;• Culling of ill and stray dogs, seldom report about the

dogs under safety culling to veterinary institutions and handle it roughly without requiring veterinary inspection.

• Low average dog immunization coverage.• Results: The veterinary department do not know the real

epidemic, the reported animal cases is far less than the reported cases of people.

Problems in Rabies Control

• The number of reported animal rabies:• ——The incidence is much lower than the corresponding period.

– Animal rabies prevention and control 2000-2006 – Year Incidence Death Toll Cull Toll– 2000 14 11 2492– 2001– 2002– 2003 862 300 909– 2004 208 57 899– 2005 337 134 14819– 2006 127 44 5681

Problems in Rabies Control

• The current monitoring does not reflect the real situation of animal rabies epidemic!

Detection and monitoring of rabies

• 2009 Monitoring: apparently healthy dogs

Detection and monitoring of rabies

• Monitoring results of dog rabies in Chongqing :

• 2009, 360 healthy dogs saliva testing, all negative;

• June 2010 in Tongliang County, Qijiang County, Qianjiang County, Fuling County collected a total of 81 healthy dogs saliva samples, all negative;

• 2005 to July 2010 in Chongqing totally detected 60 clinical samples suspected of dogs, of which 38 samples were positive.(Results see table)

• Shows: The detection of incident animal reflects more on the prevalence.

Incident Animal Saliva Detox Detection

• Experimentally infected dogs (D3, D2, D8) symptoms obviously, all dead and brain tissue FAT and RT-PCR strongly positive.

• D2 a lot of salivation (see Figure), D3 and D8 less saliva.

Incident Animal Saliva Detox Detection

• 2010 Shanxi Yangqu sheep rabies outbreak detection.

• No 1,2,3 incident sheep

saliva positive out of 5 samples;• No 4 incident sheep and early

onset of the infected dogs saliva

were negative.

Detection and monitoring of rabies

• Two errors in monitoring :• 1. Detection of healthy dogs: results are uneven, representative is not strong, can not

reflect the true situation.• Because: special transmission; healthy dogs often do not infected① ②• 2. testing saliva samples: not reliable• Because: Saliva Detox is intermittent, so can not be detected does not mean no

infection.• Results: 1. The cost of monitoring healthy animals is much higher than the incidence

animal surveillance, however the obtained epidemiological information is far less than the incident animals: from 2004-2009, monitored 12,011 samples of healthy dogs, with only 46 positive infections, involving 4 provinces and 1 species of animals (dogs); however, the detection of 98 incident animals samples found 56 positives, involving 11 provinces, 6 species of animals (dogs, pigs, cattle, sheep, raccoon, and badger.)

• 2. Animal rabies seriously underestimated: reported animal cases are more than 10 times lower than the number of the cases of people.

• Proper monitoring:Close attention to the incident animals (dogs), once found the dog with disease, abnormal behavior, or frequent wounding, should be immediately reported, cull for inspection or quarantine.

Rabies Control

• Eradication of rabies in three major strategies:

• Legislation, management and education: It is the social basis of the control of rabies.

• Epidemiological surveillance: is the prerequisite for the control of rabies.

• Immunization: an important guarantee for the control of rabies.

Rabies Control• Legislation, management and education: It is the social basis

of the control of rabies.

• Dog breeding license and registration system (including rural)• Control and eradication of stray dogs or wild dogs;• Strict immunization measures;• Establish provincial level RV testing laboratories at the provincial

veterinary quarantine station, to carry out year round RV diagnose on animal, epidemiological and immune monitoring;

• The government's administrative and financial support;• Technical training: to train specialized technical staff on RV Control

(provincial, municipal, county and township);• Community and rural education, spread knowledge of rabies

prevention.

Rabies Control

• Epidemiological surveillance: is the prerequisite for the control of rabies.

• RV natural host in the region and the infected host species, distribution and cross-border flows and so on, a clear focus on preventing the animals;

• Develop the awareness of submitting dead animals (dogs) for detection, raise the sample submission rate;

• Monitor the virus infected situation of the important host and the strains type in high infection region: Rural area with dog concentrated is the key;

• RV antibody screening on wildlife which relate to human life;• Rabies incidence and epidemiological investigation of local people

(CDC), once found the patient, should immediate conduct pointed epidemiological investigations.

Rabies Control

• Compulsory immunization: an important guarantee for the control of rabies.

• Rural dogs immunity: use attenuated vaccine, as soon as possible to contain the outbreak. Oral bait vaccine is urgently needed in rural areas.

• City pet immunity: the use of inactivated vaccine.• Wildlife immunity: oral attenuated or genetically engineered vaccine

bait.• WHO research shows that 75% of the dog group immunization rates

could high efficiently block the spread of RV chain.• Three months old dogs and cats should take the first time of

immunization, one year old to take the second time, and then immune once every year.

Rabies Control

• American rabies control achievements:• 80s PAHO implemented the "Regional plan of rabies

elimination", due to the control of the rabies virus prevalence among canine group in a greater extent, dog rabies dropped to 1,311 cases in 2002 from 6,716 cases in 1993, down rate 81%, human rabies dropped to 39 cases in 2002 from the 216 cases in 1993, down rate 82%.

Suggestion on current prevention and control

• Summarize the achievements on the work of prevention and control in recent years,, improve publicity, enhance confidence, identify problems, gaps and improve the work;

• Formulation and publish the national level rabies control and elimination programs as soon as possible, such as the “Twelfth Five Year animals canine rabies control programs”, special funds to implement prevention and control of rabies, of complete the control of canine rabies within 5-10 years;

• Each province establish integrated rabies control and management office under the direct leadership of government and composed together with relevant departments, unify organize and coordinate dog breeding management and rabies prevention and control in the province.

• Implement dog breeding licensing and registration as well as compulsory vaccination system in rural areas with more dogs, particularly in high rabies incidence area, establish monitoring mechanism.

• Governments at all levels should allocate special funds each year, specifically for the local animal immunization, surveillance and technical training, etc., to ensure periodic immunization, unremittingly.

• Animal disease prevention institutions at all levels should take the animal rabies control in the region as a routine veterinary vaccination work, establish and improve disease surveillance, reporting and handling system, report each outbreak, and to submit the clinical disease samples to reference laboratories in a timely manner.

• Conditional provincial Animal CDC should establish provincial level Rabies laboratory testing capacity, and form the network with our national laboratory.

Thank you

• Veterinary Bureau, Ministry of Agriculture• China Animal Disease Control Center• Guangdong, Guangxi, Chongqing, Shanxi,

Hunan animal epidemic control center.• Public service sectors (agriculture) research

projects “animal rabies surveillance and control technology research and demonstration”

• Rabies Expert Group of Expert Committee on Animal Epidemic Prevention