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 Presented by Prof. Eyal Klement - Koret School of Veterinary Medicine 1

…Before we start…

• RM65 vaccine – an attenuated sheep-pox vaccine manufactured by ABIC® and JOVAC®

• Each dose contains a minimum of 102.5 TCID50 of freeze dried live attenuated sheep-pox vaccine

• 1 ml administered S.C.

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…Before we start…

• Neethling vaccine – an attenuated lumpy skin disease vaccine manufactured by OBP

• Virus titer dose - 103.5 TCID50*

• 2 ml administered S.C.

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*According to registration file

Background • A large LSD outbreak spreading mostly in the north of Israel

from July 2012. • Initially, only beef herds were affected. • On October, first cases began to appear among intensive zero-

grazing high producing Holstein dairy cattle herds. • Vaccination with attenuated RM65 sheep-pox vaccine did not

seem to affect outbreak progression.

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Previous Israeli experience with RM65 vaccine

• Large outbreaks in RM-65 vaccinated herds in Israel:

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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

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Study aim

• To compare the field effectiveness of 10XRM65 and Neethling attenuated vaccines for prevention of LSD

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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.

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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

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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

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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

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Case definitions

• LSD case – a cow/calve with at least one typical LSD nodule

• Severe case - typical skin nodules accompanied by fever (>39.5 oC) 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)

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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%)

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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 (0.92-2.41) • P-value for heterogeneity = 0.122

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Crude effectiveness – severe cases

• Only cows - RRMH = 3.65 (1.59-8.35) • No significant heterogeneity

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Accumulation of cases in time

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Accumulation of severe cases in time

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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 (1.44-4.82)

• 20 cases among 10xRM65 vaccinated cows (incidence=1.3%) vs. 1 case among Neethling vaccinated cows (0.06%): RRMH=11.2 (2.3-54.7)

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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 (1.59-11.53)

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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

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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%

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…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

So...

• Which vaccine is better?

• It depends on… – Risk assessment – Epidemiological condition

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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

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