Tenacibaculum in Chile, current situation and potential preventive strategies. Jaime Tobar, PhD Virbac-Centrovet Chile

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1 Tenacibaculum in Chile, current situation and potential preventive strategies Jaime Tobar, PhD Virbac-Centrovet Chile

2 Virbac-Centrovet Founded in 1979, focused on the development of antibiotics, vitamins, premix, antiparasitic, mainly for the poultry industry. Now it becomes leader in animal health, focusing on disease prevention = Vaccines. A pioneer in the development of products for the salmon industry. Status in 2015: More than 410 workers. Completely separate facilities for production of vaccines and drugs. From Ideas to Market: R&D, Production, animal trials, Quality control, sales. The entire team. Recent agreement with Syndel for Canada and US

3 Biological Products Fish Vaccines SRS, IPN, Vibriosis, ISA Mixed and tri- tetra-pentavalent Oral Vaccines: ISA, SRS, ISA+SRS, IPN IPN immersion Autogenous vaccines Avian Vaccines Hepatitis vaccine IBV Vaccine Salmonella enteritidis E. Coli Swine Vaccines Mycoplasma hyopneumoniae oral vaccine APP (Autogenous) Clostridium (Autogenous)

4 R&D Biologicals New facilities in 2014: 1100 m2 surface fully dedicated to R&D Cell and bacterial cultures Immunology Genetic Engineering Virology Microbiology New vaccine formulations Autogenous vaccines

5 Experimental units for fish -Controlled temperature and Oxygen -Freshwater and saltwater units -Pharmaceuticals and vaccines

6 Vaccine Production facility 40+ professionals and technicians. GMP and ISO9001:2008 Guidelines European GMP Production capacity: 30 million doses/month of injectable vaccines 40 million doses/month oral vaccines.

7 Tencibaculum maritimum in Chile Main species affected: Atlantic salmon Rainbow trout Bacteria targets fish at two stages 1 month after SW transfer Adults (>1,5 Kg) Bacteria generates ulcers in mouth, head and caudal fin Morbidity can be higher than 30% Mortalities can be up to 2% Probably overestimated Can precede BKD or SRS ourbreaks Photo: Dr. Enrique Paredes (UACH) Fish loose apetite and feed conversion fall.

8 Tencibaculum status Bacteria is considered homogeneous in Chile It is found in SW and Brackish Also found at different ranges of temperature - High adaptation capacity Different triggering factors Stress (management) Low water quality (High organic material) Salinity variations Immunosuppresion

9 Treatment Treatment is ussually OTC, FFC Fish can recover, however, inside the population remain fish suppresed which do not take the medication - Preventive measures needed. Major impact in production Loss of Feed conversion Early mortality External lesions = specific markets No significant damage on the fillet Photo: Dr. Enrique Paredes (UACH) No Tenacibaculum vaccine registered in Chile.

10 Cases How we design a vaccination strategy Non Vaccinated Vaccinated Transfer to the sea Case 1 = post transfer (Stress/immunosupresion) Small fish ( g) Important costs Case 2 = Bigger fish (probably poor memory) Big fish (1,5-) Bigger costs Time (DD)

11 How we design a vaccination strategy Two major cases: after transfer and higher Masked with well known bacterial diseases such as SRS It seems a single vaccine won t be enough, since infection do not induce memory response Use known models in terms of vaccination and protection

12 The SRS problem INTESAL (2012).

13 Absorbancia 450 nm (UR) Absorbancia 450 nm (UR) SRS immunity/immune response 0 IgM anti-p.salmonis M uestreos vacuna SRS Centrovet IgM anti-p.salmonis Unvaccinated M uestreos vacuna SRS Centrovet 1.6 Vaccinated Booster UTA post vacunación

14 Wilda et al., 2012 IgM correlation with protection

15 The problem with injectable booster Risk for infection Management-related stress Immunosuppresion Time Weight gain reduction COSTS

16 Oral immunity in fish Fish are capable to absorb and present antigens in the second segment of the hidgut. Advantages: -Overcomes side effects. -Costs injection-related -Chance to apply booster(s). Disadvantages: - Antigen Integrity. -Fish must eat.

17 Immune system at the instestinal mucosa Anti-Macrophages Anti-T cells Teleost fish has all the elements needed to present antigen in mucosal tissues

18 The problem of oral vaccines Antigen integrity Proper immunity Persistence Safety

19 MicroMatrix technology MicroMatrix Gastric Juice Duodenal Juice Bacteria are encapsulated with a matrix which protects them from acidic ph. This matrix are slowly hydolised once reach the instestine, releasing vaccinal antigens.

20 Primovaccination studies -Atlantic salmon, 30 g weigth. -Dose: 6 mg vaccine per day during 10 consecutive days -Everyday fish receives orally as much antigen as 1 injection -Survival and immunological parameters

21 Anticuerpos anti-p.salmonis Anticuerpos anti-p.salmonis Humoral immunity Título de anticuerpos sistémicos UTA post vacunación 1370 Título de anticuerpos Intestinales 0.28 Oral-SRS Oral-SRS 0.26 Control Control 0.24 Inyectable-SRS Inyectable-SRS UTA post vacunación 1370 Tobar et al. Vaccine, 2011

22 % Sobrevivencia Oral vaccine protects against SRS challenge as soon as 300 day-degrees Control SRS-Oral SRS-Inyectable SRS libre Días post desafío Tobar et al. Vaccine, 2011

23 Immunological Follow-Up

24 IgM (ng/ml) Statistical analyses at 2012 more than 500 farming cycles * p < 0,05 ** p < 0,005 *** p < 0,001 Booster 1 ** * *** * * * * *** *** *** *** *** *** *** *** * Booster 2 *** *** *** *** *** ** Degree-days Tobar et al., accepted

25 IgM (ng/ml) Mortality % From lab to farm: Field case IgM (ng/ml) Daily Mortalities Degree-days Tobar et al., accepted Tobar et al., in preparation

26 IgM (ng/ml) Mortality % Accumulated mortalities reached 13% (total) IgM (ng/ml) Accumulated Mortalities Degree-days Tobar et al., accepted Tobar et al., in preparation

27 IgM (ng/ml) Mortality % SRS Mortalities were below 1% 5000 IgM (ng/ml) Accumulated SRS Mortalities Degree-days Tobar et al., accepted Tobar et al., in preparation

28 Lymphocytes? Alternative tools for evaluating immune response

29 Cantidad relativa Celullar immunity detection = Can be used on field? No much tools, no much reproducible, no commercially available CD8 + CD8 + CD8 + CD8 + CD8 + CD8 CD8 + + Need to develop alternatives in the meantime

30 To find a cell time is complex And for field we need a rapid and efficent method

31 Peaks Flow cytometry as a tool for discriminating cell types Intensity Sample: -Blood -Cells -Fluids

32 Method published in 2004 Total blood No red-cells Red Cells B A C D Neutrophils Basophils Lymphocytes Monocytes

33 Comments - Surveillance and follow-up is a key element in the development of an efficient strategy. To better support this are necessary more and better immunological tools. - It is needed to further expand the current analysis in order to determine the role of diferent factors, such as fish species, stationality, densities, and others. - The understanding of fish immune system and its interaction with vaccines or vaccine components, such as adjuvants, becomes pivotal in order to develop more long lasting vaccines. - New delivery routes for vaccines are important for fish farming: Oral vaccination reduces costs, stress-derived management, and enhances the sanitary status.

34 Why following immune response?

35 Understanding the conditions of success - Vaccine, unlike antibiotics, need and intermediate in charge of clearing the pathogen CD4 CD8 B Keep healthy fish is a key element for vaccine success

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