EPIDEMIOLOGICAL FACTORS AND CONTROL OF RABIES IN NORTH AFRICA
OIE GLOBAL CONFERENCE ON RABIS CONTROL Incheon (Republic of Korea) : 7-9 september 2011
EPIDEMIOLOGICAL FACTORS AND CONTROL OF RABIES IN NORTH AFRICA...
OIE GLOBAL CONFERENCE ON RABIS CONTROL Incheon (Republic of Korea) : 7-9 september 2011
EPIDEMIOLOGICAL FACTORS AND CONTROL OF RABIES IN NORTH AFRICA
Mehdi EL HARRAK DVM PhD, Biopharma Lab, Rabat Morocco
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NORTH AFRICA REGION Border: Mediterranean sea N to Grand Sahara S, Atlantic W to Egypt. Total area: 4 Millions Km2 4countries : Morocco, Algeria, Tunisia, Lybia. Inhabitants: 90 millions, 45 % rural population Livestock: 70 M large animals Dog estimated Population: 4-5 millions
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RABIES IN NORTH AFRICA Rabies is a serious public health concern in North Africa causing a heavy social and economic burden Its reintroduction represents a threat to Western European countries presently free of canine and vulpine rabies, but they continue to declare some human and animal cases mostly imported from North Africa. Legislation: Rabies is a Reportable Disease in NA countries This presentation will address a global multidisciplinary approach to draw a precise picture of the rabies epidemiology in North Africa by identifying key factors for rabies dynamics and provide recommendations for prevention and control strategies. Data provided by the RABMEDCONTROL project (http://www.rabmedcontrol.org/), funded by the EU.
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Animal Rabies in Algeria
4
1000 1000
889 869 907
851
900 800
Nbre des foyers
Rabies present a public health problem despite the establishment of a national committee rabies control in1984. It endemic with a seasonal peak in spring 950 cases reported yearly. The regions most affected are the center of the country and coastal areas. The South is free of rabies, The dog is the main reservoir of the disease (average prevalence of about 50% of reported cases). The bovine remains the main victim of the disease, after the dog
The disease is endemic, cases of animal rabies reported annually (average 386 cases per year) In general, the evolution curve of human rabies follows that of animal rabies All provinces are affected but to varying degrees except the southern desert The dog is the source of all contamination, but ruminants are the main victims
Global Epidemiological situation in NA •Dogs remain the main reservoir and transmitter of rabies (40 to 70 % of notified cases) •85% cases are from rural areas •Ruminants (19-31-39%) and equines (6-19-8%) are the main victims of rabies among livestock species •Southern desert provinces are free from rabies
Animal Rabies Urban 15% Rural 85%
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CURRENT ANIMAL RABIES COST (MOROCCO) 8
Livestock mortality 500.000 $ Mass vaccination cost 350.000 Reduction of dog population 500.000 Additional equipment 210.000
Total rabies annual cost: 1.500.000 $ US
HUMAN RABIES IN NORTH AFRICA Average of 22 per year human fatalities in Morocco and Algeria (12-35) 1 to 3 per year in Tunisia 86% unvaccinated, 14% interrupted PET 89 % due to dog bites with mostly unknown origin Children: major victims of canine rabies (56%)
35 30 25
4 inj
(29%)
3 inj 2 inj
1 inj
25%
20
(17%)
15 (10%)
10
(8%) (6%)
5
(5%)
0 0-9
10-19
20-29
30-39
40-49
50-59
60 et+
Age distribution of human rabies fatalities
Non vaciné s
Vaccination status
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HUMAN RABIES FINANCIAL IMPACT
Around 150.000 persons receive yearly PEP treatment after a potential rabies exposure in NA 120 PEP Centers present in Morocco Average PEP treatment cost 90 $/person PEP entirely supported by governments. Global Human rabies prevention cost around 2 M $ per year That include only biological, PEP centers management and rehabilitation to be added.
Phylogeny of rabies isolates Phylogeny of rabies isolates collected from the North and the Sahel regions of Africa show: Strong spatial segregation of the circulating isolates, with no exchange between North Africa and the Sahel region Limited diffusion from one country to the other Limited movements between Algeria and Morocco Strong population subdivision at the country level Evidence that the periodic reintroduction of rabies virus to Europe is mainly due to an illegal importation of dogs from North Africa. Phylodynamics and Human-Mediated Dispersal of a Zoonotic Virus Talbi et all; PLoS Pathogens | www.plospathogens.org 1 October 2010 | Volume 6
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Phylogeography of RABVc in North Africa 1938 (1873-1930)
100
EGYPT
100
TUNISIA
1950 (1938-1966) TMRCA 1882
1 2
MELILLA 100
(1866-1921)
MELILLA CEUTA
3
100 1956 (1940-1962)
MORROCO 100
ALGERIA
MCC tree of 207 N sequences of Africa1 clade.
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CONTROL STRATEGY
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CONTROL STRATEGY IN ALGERIA
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Multiannual program initiated in 1996 mainly based on three actions: Reduction of stray animal population Vaccination of domestic carnivores; Vaccination of Cattle (since 2003) Data from this program for the year 2007 Number of Dogs and Cats vaccinated 21 768 Cattle vaccinated 802,770 Since the beginning of the operation: Number of animals vaccinated: 1900000 Number of carnivores killed stray: 220000
CONTROL STRATEGY IN TUNISIA
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evolution de l'incidence de la rage canine et de la vaccination des chiens en Tunisie (1983-2006)
ed en ed in e en Ru in ra e l Su M bu ed r b en an in e M U ed rb an en in e M To an ta ou M l an ba ou Ru ba ra l Su bu M an rb ou an ba M Ur an ba ou n ba Ka To ss ta Ka er l in ss e er Ru in e ra Su l Ka bu ss rb er an in e Ka Ur ss ba er n in e To ta l
250
80%
M
Nombre de cas de
350 000
Vaccinations
Two components of rabies control program Vaccination & stray dog population control Vaccination coverage estimated at 48%
M
400 000 300
Nombre de vaccinations
350
100%
CONTROL STRATEGY IN MOROCCO 1986: first Rabies National Control Program 2001: Implementation of a new rabies control strategy on 2001 Average of 300 000 dogs vaccinated /year and 30 000 eliminated. Vaccination coverage estimation 20%
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Rabies Control Program Limits Shortage in financial and/or human resources; Inaccessibility to a large fraction of the dog population High turnover rate of dog populations Deficiency in public education; Insufficient dog owners participation Insufficient knowledge on rural canine population dynamic. Inadequate coordination between involved departments due to non clearly defined responsibilities Vaccination coverage established in the dog population is not high enough to break the transmission cycle of the disease
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DOG DENSITY IN NORTH AFRICA
Country/Dog Population
Urban pop
Rural pop
Morocco
0.6
1.6
Algeria
1.8
2.6
Tunisia
1.3
2.1
-
5.9
Egypt
Dog Ratio/householder
19
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DOG POPULATION DYNAMIC Young Population (2 – 3 years), 62% rural High mortality rate the first year Males Dominants (60 -78%) Majority accessible to vaccination Determination of stray dogs percentage is necessary for oral vaccination program. High turn-over rate may impose at least one vaccination campaign per year
Conclusion Despite the substantial committed efforts, rabies is still endemic and not under control in the North African countries and continue to cause human fatalities and hundreds of animal cases: A dynamic canine population (30% estimated turn over) leading to an insufficient vaccination coverage & supposes that at least one vaccination campaign per year should be targeted Ecologic factors of dogs and the impact of human socio-cultural perturbations and human behaviour may play a role in rabies dynamics and vaccination efficiency
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Investigate socioecological factors of dog population Improve infrastructure: rural slaughter, solid waste treatment, etc..
Problème sectoriel
Continue and strengthen the efforts of parenteral vaccination
Oral vaccination for inaccessible dogs
Strengthen intersectoral collaboration
Solution sectorielle
Associate / involve the Commons in the fight against rabies
