A study on serological and molecular epidemiology FMD virus circulating in Ethiopia and selection of the possible vaccinal strains (2008-2009) By Gelagay Ayelet National Veterinary Institute 1st East African FMD laboratory network meeting and workshop Kenya-Nairobi 8-12 February, 2010 Introduction The study was conducted by EUFMD funded project with main objectives •To determine seroprevalece of FMD •To assess potential risk factors associated with FMD •To assess importance of FMD infection •To identify the serotypes and topotypes circulating in the country Cont.. To conduct this investigation MVSC/DVM (Totally six students ) Study areas 1. South Omo (Southern Ethiopia, pastoralism, Kenya and Sudan border) 2. Borena (Pastoralism, Kenya border) 3. Highland areas (Amhara, Mixed farming system) 4. Addis Ababa and its surrounding ( Current ) 5. Tigary, Northern Ethiopia ( Current ) 6. Gambella (Current ) Figure 1: Study areas selected Norht Gonder Addis Ababa Awi West Gojjam South Omo Borena Materials and methods Data • Disease report of MOARD • Questionnaire • Collection of Epidemiological data and samples during outbreaks • Sera Sample processing • Virus isolation • PCR • Serology • Molecular analysis and vaccine Matching (Pirbright, UK) Cont… During the study period (2008/9) FMD outbreaks were investigated in • Amhara regional state in Six districs (Bahir Dar zuria, Yilmana Densa, Dangla, Sanja and South Achefer districts and Debre Birhan ) • SNNPRS one outbreak in South Omo zone • Oromia regional state Four outbreaks (Haromya, Sina, Sululta and Yabello districts) • Three outbreak from Addis Ababa were investigated. • Totally 64 tissue samples and 2034 sera samples were collected and examined. • Cattle, swine, sheep and goats were affected during outbreaks . Results Figure 2. No of Outbreaks reported (MOARD) 80 70 60 50 2008 40 2009 30 Total 20 10 0 Oromia Gambella Benshagul Amhara Addis Ababa SNNPRs Tigray Total 2008 23 0 1 7 3 1 4 39 2009 26 1 0 3 1 0 33 Total 49 1 1 10 5 2 4 72 Figure 3: Areas of FMD outbreaks reported 2008/09 (MOARD) Key Areas of FMD outbreaks reported Areas of FMD sample collected Cont… Virus isolation, serotype and topotype identified • Out of a total of 64 bovine and swine cultured samples, 39 (samples were showed FMDV cytopathic effect (CPE) on BHK-21 monolayer cells culture for FMD virus. • A total of 39 tissue cultured FMD virus samples were submitted to WRL Pirbright, UK. Among those samples, serotype O from 16 samples and serotype A from 3 samples were isolated and confirmed . Table 1: Summary of presence of cytopathic effect on tissue cultured and serotype and topotype identified Year of Species of animal No. of Serotype Topotype Site of Outbreaks Showing CPE Strain No. sampling samples identified identified 1 Bahirdar Zuria 26/08/08 Cattle 5 2 O EA-3 - 2 Yilmana-Densa 2008 Cattle 5 3 O EA-3 - 3 South Achefer 19/10/08 Cattle 7 3 O EA-3 - 4 Dangela 11/02/09 Cattle 4 1 O EA-3 - 5 Addis Ababa 01/11/08 Cattle 4 2 O EA-3 - 6 Haromaya 11/03/09 Cattle 5 5 O EA-3 - 7 Sinana 08/08/08 Cattle 2 2 A Africa G-VII 8 Yabello 01/08/08 Cattle 1 1 A Africa G-VII 9 South Omo 05/01/09 Cattle 6 - - - - 10 Sanja 18/01/09 Cattle 3 - - - - 11 Addis Ababa 17/11/09 Cattle 2 2 ? 12 Debre Birhan 19/11/09 Cattle 9 7 ? 13 Debre Birhan 19/11/09 swine 3 3 ? 14 Addis Ababa 18/11/09 Cattle 4 4 ? 15 Sululta 29/12/09 Cattle 4 4 ? Total 64 39 Key: ? = Not yet processed/submitted to WRL Table 2: Seropositivity using ELISA test (Cedi test) Region Zone No. cattle No. of Sero District tested Positive Positive (%) South Achefer Amhara W. Gojam 101 53 52.48 Addis Ababa Addis Ababa Akaki 46 13 28.30 Yilmana Densa Amhara W.Gojam 98 37 37.76 Dangela Amhara Awi 104 45 43.27 Haromaya Oromia E. Harerge 35 28 80.00 Bahirdar Zuria Amhara W. Gojam 112 43 38.39 Gnangatom SNNPRS/ S. Omo 61 8 13.1 Jinka SNNPRS S. Omo 162 8 4.9 Hammer SNNPRS S. Omo 104 14 13.5 Malle SNNPRS S. Omo 123 4 3.3 Semen Aari SNNPRS S. Omo 142 4 2.8 Bennatsemay SNNPRS S. Omo 94 19 20.2 Dasanech SNNPRS S. Omo 84 6 7.1 Teltele Oromia Borena 248 39 15.7 Yabello Oromia Borena 296 71 24.0 Arero Oromia Borena 224 67 29.9 Total 2034 459 22.6 Table 3 : Summary of OR, p-value and 95% CI (OR) of risk factors associated with FMD using multivariate logistic regression (Borana). No tested No Seroprevalence SE P-value OR 95% CI(OR) Risk factors positive (%) District Teltele 248 39 15.7 - - - - Yabello 296 71 24.0 0.230 0.028* 1.658 1.056-2.604 Arero 224 67 29.9 0.237 0.001* 2.261 1.420-3.601 Age < 2 years old 252 21 8.5 - - - - 2-4 years old 280 51 18.2 0.327 0.010* 2.323 1.226-4.417 >4 years old 236 77 32.6 0.301 0.000* 4.864 2.695-8.778 Sex Female 526 137 26.0 - - - - Male 242 40 16.5 0.221 0.419 0.836 0.542-1.290 Herd size < 50 cattle/ herd 256 42 16.4 - - - - 50-100 cattle/ herd 264 59 22.3 0.233 0.055 1.565 0.990-2.473 > 100 cattle/ herd 248 76 30.6 0.226 0.001* 2.101 1.350-3.272 Constant 0.363 0.000 0.042 Fig 4: Seroprevalence of FMD in South Omo zone and associated risk factors Risk Factors No of animals Seropositivity n 95 % CI examine (%) d Lower Upper Districts Gnangatom 61 8 (13.1) 6.8 23.8 Jinka 162 8 (4.9) 2.5 9.4 Hammer 104 14 (13.5) 8.1 21.3 Malle 123 4 (3.3) 1.3 8 Semen Aari 142 4 (2.8) 1.1 7 Bennatsemay 94 19 (20.2) 13.3 29.4 Dasanech 84 6 (7.1) 3.3 14.7 Movement pattern Limited movement in District 271 9 (3.3) 1.8 6.2 Cross District border 136 13 (9.6) 5.7 15.7 Cross parks and sanctuaries boundary 265 31 (11.7) 8.4 16.1 Cross national boundary 98 10 (10.2) 3.4 15.1 Age category Less than 2 years 202 4 (1.98) 0.7 4.9 Between 2 to 4 years 274 19 (6.93) 4.5 10.6 Above 4 years 294 40 (13.6) 10.2 18 Distance from parks and Less than 10 km 371 42 (11.3) 8.5 14.9 wildlife sanctuary (km) Between 10 to 200 km 257 17 (6.6) 4.1 10.3 Above 200 km 142 4 (2.8) 1.1 7 Contact history with Regular contact 190 23 (12.1) 8.2 17.5 wildlife By monthly time 176 18 (10.2) 6.6 15.6 Only in dry season 145 11 (7.6) 4.3 13.1 Rare contact 77 1 (1.29) 0.2 7 No contact at all 182 10 (5.49) 3 9.8 Total 770 63 (8.2) 6.4 10.3 Cont.. FMD occurrence in Hammer by Association of FMD and wild life contact, Hammer season long cold dry, 100 rainy, 20% 0% FMD occurrence 10 contact to w ild animals short long dry, num ber of sick 60% dry, an im als in h erd 20% 1 long rainy cold dry short dry long dry Season of the year Table 5: Seropositivity using ELISA test (Highland) No. of No. of Sero Risk factors cattle 95% CI χ2 P-value Positive Positive (%) tested District South Achefer 101 53 52.48 42.83- 61.95 Akaki 46 13 28.30 17.32 – 42.55 Yilmana Densa 98 37 37.76 28.80 – 47.65 Dangela 104 45 43.27 34.16 – 52.86 Haromaya 35 28 80.00 64.11 – 89.96 BahirdarZuria 112 43 38.39 29.91 –47.64 Total 496 219 44.20 39.84 – 48.55 28.96 0.000 Age <2 years 48 17 35.42 23.44 – 49.56 2-4 years 157 59 37.58 30.39 – 45.37 > 4 years 291 143 49.14 43.44 – 54.86 Total 496 219 44.20 39.84 – 48.55 7.17 0.028 Breed Crossbred 46 13 28.26 17.32 –42.55 Exotic 35 28 80.00 64.11 –89.96 Indigenous 415 178 42.89 38.21 – 47.70 Total 496 219 44.20 39.84 – 48.55 23.22 0.000 Sex Female 282 122 43.26 37.61 – 49.09 Male 214 97 45.33 38.80 – 52.02 Total 496 219 44.20 39.84 – 48.55 0.21 0.646 Table 6: The morbidity, mortality and case fatality rates in different risk factors (Highland) No. at No. No. Morbidity 95% Mortality Case fatality Risk factors 95% CI 95% CI Risk affected dead rate (%) CI rate (%) rate (%) District Bahirdar Zuria 2614 144 7 5.51 0.05-0.06 0.27 0.13 -0.55 4.86 2.41 – 9.69 Yilmana Densa 1557 134 2 8.61 0.07-0.10 0.13 0.04-0.47 1.49 0.41-5.27 South Achefer 1493 215 6 14.40 0.13-0.16 0.40 0.18 –0.87 2.79 1.31 – 5.94 Dangla 1189 86 3 7.23 0.05-0.09 0.25 0.08-0.74 3.49 1.17-9.75 Akaki-kality 71 15 1 21.13 0.13-0.32 1.41 0.25-7.56 6.67 1.19-29.82 Haremaya 203 41 0 20.20 0.15-0.26 0 0.01 –1.79 0 0.06 – 8.40 Total 7127 635 19 8.91 0.08-0.09 0.27 0.17-0.42 2.99 1.92-4.62 Sex Male 2844 258 5 9.07 0.08-0.10 0.18 0.08-0.42 1.94 0.83-4.46 Female 4283 377 14 8.80 0.08-0.09 0.33 0.2-0.55 3.71 2.22-6.13 Total 7127 635 19 8.91 0.08-0.09 0.27 0.17-0.42 2.99 1.92-4.62 Husbandry Intensive 274 56 1 20.44 16.09-25.61 0.36 0.06-2.03 1.79 0.32-9.45 Extensive 6853 579 18 8.45 0.16-0.41 0.26 1.98-4.86 3.11 1.98-4.86 Total 7127 635 19 8.91 0.08-0.09 0.27 0.17-0.42 2.99 1.92-4.62 Figure 5: Morbidity, mortality and case fatality rates in different age groups Figure 6: Morbidity, mortality and case fatality rate in different breeds of animals Conti… From the various risk factors analyzed – Contact history to wild animals – Farming system (intensive) – Movement pattern of herds in search of pasture and water from area to area – Age and breed of animal, – Herd size were found to be significantly associated (P<0.05) with the occurrence of FMD.