Comparison of the effectiveness of Neethling LSD and 10xRM65 sheeppox attenuated vaccines - The results of a randomized controlled field study

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1 Comparison of the effectiveness of Neethling LSD and 10xRM65 sheeppox attenuated vaccines - The results of a randomized controlled field study Koret School of Veterinary Medicine Israel Veterinary services Kimron Veterinary Institute Hachaklait 1 Presented by Prof. Eyal Klement - Koret School of Veterinary Medicine

2 Before we start RM65 vaccine an attenuated sheep-pox vaccine manufactured by ABIC and JOVAC Each dose contains a minimum of TCID50 of freeze dried live attenuated sheep-pox vaccine 1 ml administered S.C. 2

3 Before we start Neethling vaccine an attenuated lumpy skin disease vaccine manufactured by OBP Virus titer dose TCID50* 2 ml administered S.C. *According to registration file 3

4 Background A large LSD outbreak spreading mostly in the north of Israel from July Initially, only beef herds were affected. On October, first cases began to appear among intensive zerograzing high producing Holstein dairy cattle herds. Vaccination with attenuated RM65 sheep-pox vaccine did not seem to affect outbreak progression. 4

5 Previous Israeli experience with RM65 vaccine Large outbreaks in RM-65 vaccinated herds in Israel: 5

6 Data regarding Neethling and 10XRM65 vaccines No controlled clinical trial evaluating the effectiveness of these vaccines Anecdotal data pointing of possible effectiveness of the Neethling disease for controlling LSD in South Africa Anecdotal data stating the RM65 vaccine in a x10 dose is more effective than the regular dose 6

7 Study aim To compare the field effectiveness of 10XRM65 and Neethling attenuated vaccines for prevention of LSD 7

8 Vaccine preparation Neethling According to manufacturer instructions. 2 ml injected S.C. 10xRM65 Use 1/5 of the diluent recommended by the manufacturer and inject 2 ml S.C. 8

9 Study population 15 dairy cattle herds located in the north of Israel 4694 cows and 3756 calves and heifers All herds vaccinated 3-5 months previously with an RM65 attenuated vaccine 9

10 Study design Cows randomized according to skin number: Even Neethling Odd 10xRM65 In 7 farms all calves were vaccinated with the Neethling vaccine In 8 farms all calves were vaccinated with 10XRM65 vaccine 10

11 Surveillance All cattle in the herds were monitored daily by the herdsmen for any sign of LSD or other illness Suspected illness was examined by the herd veterinarian twice weekly and informed immediately to the study veterinarian When possible, the study veterinarian collected blood and skin specimen biopsies from affected animals 11

12 Case definitions LSD case a cow/calve with at least one typical LSD nodule Severe case - typical skin nodules accompanied by fever (>39.5 o C) or by a decrease in milk yield of over 20% Laboratory confirmed case identification of wild strain by PCR from either skin biopsy or blood (Menasherow S et al. J Virol Methods, 2014) 12

13 Results 82 cases occurred in 8 herds which included 5546 vaccinated cows and calves (incidence = 1.5%) Among cows only the incidence was 76/3077 (2.5%) 13

14 Crude effectiveness (cows only) In 5 herds higher morbidity in 10xRM65 vaccinees. In 2 herds Higher morbidity in Neethling vaccinees In 1 herd Equal morbidity RRMH = 1.49 ( ) P-value for heterogeneity =

15 Crude effectiveness severe cases Only cows - RRMH = 3.65 ( ) No significant heterogeneity 15

16 16 Accumulation of cases in time

17 17 Accumulation of severe cases in time

18 Effectiveness (cows)- >14 days post vaccination 42 cases among 10xRM65 vaccinated cows (incidence=2.7%) vs. 13 cases among Neethling vaccinated cows (0.84%): RRMH=2.64 ( ) 20 cases among 10xRM65 vaccinated cows (incidence=1.3%) vs. 1 case among Neethling vaccinated cows (0.06%): RRMH=11.2 ( ) 18

19 Effectiveness (cows)- Isolation of wild strain 22 cases among 10xRM65 vaccinated cows (incidence=1.4%) vs. 6 cases among Neethling vaccinated cows (0.84%): RRMH=4.28 ( ) 19

20 Neethling s disease 9 confirmed cases out of 2356 vaccinated cows (incidence= 0.4%). Of these 1 severe case All occurring within 14 days from vaccination No Isolation of Neethling strain from a non- Neethling vaccinated cow 20

21 Final conclusions Relative effectiveness Neethling vaccine is significantly more effective in preventing LSD. Relative effectiveness for preventing LSD in cows when full immunity is anticipated (i.e. >14 p.v.) = 62% Relative effectiveness for preventing severe LSD = 91% Relative effectiveness for preventing confirmed LSD = 77% 21

22 However Neethling s disease: 0.4% incidence of Neethling s disease durig the 14 days post vaccination. Mostly non-severe disease though no evidence of transmission of the Neethling strain to non-neethling vaccinated cows Outbreak control Outbreak was fully controlled with extensive use of both vaccines. Therefore it is conceivable that 10xRM65 is also effective in preventing LSD 22

23 So... Which vaccine is better? It depends on Risk assessment Epidemiological condition 23

24 Thanks Prof. Nahum Shpigel Study initiation, design and conduction Dr. Nadav Galon and veterinary services study support, and vaccination performance Dr. Yonatan Ben-Gera Study conduction and data coordination Dr. Yevegeny Chinitz and Dr. Yehuda Stram virus isolation and identification Dr. Benny Sharir, Hachaklait veterinarians vaccination and clinical surveillance Herdsmen 24