11/4/2016. Overview. History of Brucellosis. History of US Brucellosis program

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1 Overview NATIONAL BRUCELLOSIS ERADICATION PROGRAM UPDATE USAHA 2016 MARK CAMACHO DVM, MPH NATIONAL CATTLE HEALTH EPIDEMIOLOGIST U.S. DEPARTMENT OF AGRICULTURE ANIMAL AND PLANT HEALTH INSPECTION SERVICE VETERINARY SERVICES OCTOBER 18, 2016 Brief history of brucellosis eradication program US Basic control strategy Historical surveillance Current brucellosis status US cattle demographics Current surveillance/tracing Questions? 2 History of Brucellosis 450 BC: Described by Hippocrates 1859: Described by Marston (Malta Fever) 1884: Capt. David Bruce isolates B. melitensis from soldiers. Epi link to goats milk 1895: Danish Vet Path Benhard Bang identifies B. abortus in cattle Fig 1. Crimean War soldiers recuperating in Cottonera Hospital ward, Malta ~1880. Source: Times of Malta History of US Brucellosis program : USDA BAI recognizes bovine infectious abortion as a major problem plus serious public health concerns 1934: Start of US Brucellosis eradication program 1941: Strain 19 vaccination approved 1947: First UMR published, milk pasteurization becoming standard in metropolitan areas 1952: BRT testing begins 1954: Congressional funds first approved 2000: No infected herds for 1 st time in the USA Fig 2. British Army Physician, Capt. David Bruce ( ) 3 4 1

2 History of US Brucellosis program 1934: Seen as the most important bovine disease at that time Reactor rate in US cattle > 11% 1954: Animal production and public health concerns prompted Congressional funds Designed as a cooperative program between federal, state and industry History of US Brucellosis program 1957: 124,000 affected US herds Perhaps only 1/3 to ½ of actual number Fig 3. Infected US herds in February 1957 Source: VE Ragan / Veterinary Microbiology 90 (2002) History of US Brucellosis program 7 Fig 4. Infected US herds in Source: VE Ragan / Veterinary Microbiology 90 (2002)

3 Annual human brucellosis cases and cattle herd reactor rates in the US, = US Herd reactor rate = US # Human cases Fig 5. Human Brucellosis cases in the US Source: VE Ragan / Veterinary Microbiology 90 (2002) Source: Glynn MK, Lynn TV. Brucellosis J Am Vet Med Assoc 2008;233(6): Historical surveillance Program started with down the road testing (area testing of all herds) Slaughter surveillance was then added later to the program BRT testing added to program in 1952 Then, 1 st point market testing was added in high risk areas in the 1970 s Indemnity was used to gain producer cooperation And adult vaccination (live attenuated Strain 19) became an essential tool in cleaning up affected herds (Prior to 1941, Dr. John Buck of US BAI left brucellosis cultures on his desk for over a year and found that culture 19 was very stable with low pathogenicity. Originally used as a calf hood vaccination and could cause abortion in adults.) How did the brucellosis program start? Program started with the Standard Plate and Tube tests Standardization of testing protocol was a problem with 14 serologic tests Test herds Area, slaughter, BRT, FPT, pre movement Vaccinate calves to increase resistance Remove reactors with indemnity or depopulate Epidemiologic trace testing and high risk area testing to remove pockets of infection Use adult vaccination to clean up infected herds

4 Historical surveillance In 1956 there were ~124,000 affected herds By 1992, there were only ~ 700 affected herds (<99.4%) No infected dairies in the US since, 1998 Basic Program Standards 95% slaughter surveillance 2 4 rounds BRTs annually 95% case closures 90% MCI trace backs Mandatory annual reports Goals of Brucellosis program 1. Detect 1 case per 100,000 animals with 95% confidence 2. Document ongoing disease freedom 3. Meet OIE standard of detecting.2% herd prevalence Current National Slaughter Surveillance 1. For 50 years we collected 95% of ~5 7 million adult cull cattle per year from all Top 40 adult kill plants 2. Today we sample 1.5/6 million (30%) from 11 plants (9 cattle & 2 bison) 3. 55% of samples to KY Lab, rest to TX 4. Current plants chosen by geographic footprint, GYA coverage and ability to collect quality samples Brucellosis Eradication Program State Status Classification 2016 WA MT ND MN OR ID WI MI WY SD NY IA CA NV PA NE OH UT IL IN CO MO KS WV VA KY AZ NC OK TN NM AR AL SC MS TX LA GA AK FL HI Class A Status Free Current Year Free 6-10 yrs Free yrs Free 1-5 yrs Free yrs Free 21+ yrs ME VT NH MA RI CT NJ DE MD VI. PR

5 Current US Brucellosis Status 50 class free states since 2009 The Greater Yellowstone Area including Idaho, Montana and Wyoming are now our primary focus for brucellosis in livestock due to endemic disease in wild elk and bison 2016 Brucellosis Affected Herds Bison, Test and Remove Idaho ( Montana Bison, Test and Remove Bison, Test and Remove Wyoming Idaho herd released from QT in December 2015 WY Antler Ranch bison herd released from QT in November 2015 MT herd still under QT In FY 2016, WY found two new beef herds. One went off QT in July 2016 leaving just one still under QT. Utah Brucellosis Affected Herds Idaho herd released from QT in December 2015 WY Antler Ranch bison herd released from QT in November 2015 MT herd still under QT In FY 2016, WY found two new beef herds. One went off QT in July 2016 leaving just one still under QT. Total US cattle & calves (NASS 2016) 92 million head (up 3% from 2015) Total US adult cattle and cattle herds 40 million adults and 913,000 herds (2012 NASS) US Dairy cattle (1 st calf heifers) 9.3 million head (10% of total) on ~44,000 dairy herds (5%) US Beef cattle 30.7 million head

6 Total US Cattle Herds 2016 (913,000 total herds) 44,000 Total US Cattle 2016 (92 million head) 869,000 Dairy herds = 4.8% Beef herds = 95.2% 52 Heifers & Calves 40 Adults Dairy Herds Beef Herds Adults Heifers & Calves Total US Adult Cattle 2016 (40 million head) Total US Adult Cattle 2016 (40 million head) Dairy cattle = 23% Beef cattle = 77% Used to collect blood on 95% of adults killed annually. These are legacy members of our national herd. Now collect 30% (1.5 M) of adults culls Annual Adult culls = ~5 7 million head Annual Adult Dairy culls = ~3 million Annual Adult Beef culls = ~2.5 million Dairy cow cull rate = 32% Beef cow cull rate = 8% Total Adult cull rate = 15% Dairy Cattle Beef Cattle Dairy Cattle Beef Cattle Beef Culls Dairy Culls

7 Surveillance Streams (prior to 2011) 2016 Surveillance Streams 1. Slaughter surveillance (95% adults) 1. Slaughter surveillance (9 cattle & 2 bison) 2. BRT of dairies (2 4 rds annually 100%) 2. BRT of dairies (paid for by states now) 3. FPT at selected markets 3. Herd certification testing (but very low) 4. Herd certification testing 4. Infected herd trace testing (epidemiology) 5. Infected herd trace testing (epidemiology) 5. Diagnostic testing by private practitioners 6. Diagnostic testing by private practitioners 6. GYA/DSA protocols MCI Surveillance (thru Aug 2016) Slaughter Plants collecting samples WA ME MT ND VT OR MN NH ID WI SD NY MA MI CT WY RI IA PA NE IL IN OH NJ NV CA UT DE MO WV MD CO KS VA KY NC TN OK AZ NM AR SC AL MS GA V.I. LA TX FL State Plant % to collect Est. Samples # collected (%) Testable samples # missing & invalid % missing & invalid CA Cargill 100% 180, ,533 (66%) 116,494 3, % CO Brush* 100% 20,000 16,794 (84%) 16, % CO Double J* 100% 6,000 7,855 (131%) 7, % FL Central** 33% 16,665 17,370 (35%) 16, % MN Long Pr. 100% 138, ,122 (99%) 134,107 2, % NE Gibbon 100% 410, ,614 (92%) 363,373 14, % PA Taylor 33% 115,000 98,793 (86%) 92,908 5, % TX Caviness 100% 250, ,198 (175%) 432,172 5, % TX Lone Star 100% 188, ,580 (134%) 251,079 1, % UT D T Smith 100% 75,000 54,655 (74%) 54, % WI Valley Pride 100% 110,000 74,568 (68%) 72,532 2, % Totals 1,508,665 1,593,082(106%) 1,554,989 38, % P.R. 27 * Bison plant. ** FL plant no longer in business and not collecting samples 28 7

8 Brucellosis Testing & Vaccination comparison Year Slaughter Testable samples GYA Testable samples Total MCI tests Calf hood vaccinations Adult vaccination Certified herds ,603, ,506 1,726, , , ,554, ,166 1,717,155 3,955, , Sample Size Calculations for surveillance USDA APHIS 2007 (NSU) Cannon & Roe 2001 To detect 1:100,000 prevalence at 95% confidence assuming a protocol Se of 83% = = 350,000 brucellosis samples US Brucellosis samples VS collects 1.7 million samples per year 5 times above our detection standard Note: Vaccination numbers reported by states Program Numbers (thru August 2016) Market Cattle Identification (MCI) Surveillance: 1,717,155 head of cattle tested (slaughter + GYA) 1.7% of total US cattle were sampled 4% of all US slaughtered cattle 30% of annual adult cattle killed Still can detect 2 cases/million 95% Conf Brucellosis Slaughter Surveillance Plan Laboratories Federal laboratory in Kentucky as the primary surveillance laboratory. Texas State laboratory test national slaughter surveillance samples from 2 slaughter facilities in Texas. State laboratories in the three GYA States for all samples that are collected within those States

9 National Slaughter Testing Responder Rate 2016 Brucellosis Lab Numbers (thru July 2016) The average responder rate (BAPA+ and FPA +) is roughly.01% or 10 per 100,000 or a specificity of around 99.99%. (Belfrage & Camacho) KY Lab consistently runs lower than TX Lab. Why? Significant variations away from 10 responders per 100,000 will trigger further investigation 2016 responder rate = 6.2 per 100,000 State Lab # samples received Testable samples # FPA nonnegatives (>20mP) # FPA cases per 100,000 Average FPA(mP) Test Regimen Specificity KY Lab 874, , mP % TX Lab 628, , mP % Totals 1,502,648 1,470, N/A % Total 2016 Trace Investigations 148 To 15 different states Brucellosis Trace Investigations 2016 Brucellosis Slaughter Tracing (example) National Brucellosis Trace Statistics 92 FPA positives (>20mP) with no confirmed cases Labs contact states of origin to begin traces and Epis enter traces into EMRS 148 trace investigations reported (FPA suspects = (10mp 20mp) Only 34 Index cases entered in EMRS? CHC is updating EMRS investigation tracking protocol How to correlate NVSL non neg results to investigations? Date Assigned Backtag # DAH vet case assigned to TTR/ Herd Owner Slaughter Plant Case # Date retested TTN COMMENTS Closed herd, 100% vaccinated, cow was pregnant, sick with 5/9/ PR2634 Deveau Phil Kubishak Long Prairie, MN No herd test required mastitis when shipped. TTN Closed 5/13/16 Equity Coop, No herd test Trace sent back to Iowa (Had an Iowa brucellosis 6/23/ TGW4329Doescher Rick Oswald Waukon, IA required TTN tag) Richard 53 herd samples tested 7/11/ MX2896 Doescher Wittmann Long Prairie, MN /18/2016 TTR negative

10 2016 Brucellosis Slaughter Tracing (example) Kubishak Farm The cow was a 4 year old official vaccinate who was shipped due to mastitis and Johnes ELISA positive and was also pregnant. Herd closed since 2007 and no purchases for more than 10 years. No herd fertility problems observed. Herd veterinarian conducts monthly herd health visits. Brucellosis epidemiologist decided no herd test was required. Oswald Farm The animal had an Iowa ear tag. Rick Oswald does not purchase animals, all are home born and raised. All his heifers are Brucellosis vaccinated by local veterinarian. National Standardized Testing Protocol Classification of Brucellosis Tests in US testing protocol: Screening Test BAPA RAP Primary Confirmatory Test FPA Secondary Confirmation Test Complement Fixation Supplemental Test 8% Card ELISA/BRT/HIRT Plate/Standard Plate Test Rivanol Tube/Standard Tube Test Western Blot National Standardized Testing Protocol Due to extremely low prevalence the US program requires very high specificity (minimize costs of false positives) Screening test followed by confirmatory Standardized Testing protocol (2014) = BAPA/RAP >> FPA in series to maximize specificity, minimize cost Brucellosis Slaughter Surveillance Plan 9 Cattle & 2 bison surveillance slaughter facilities GYA states Non DSA slaughter testing DSA slaughter testing Market and On farm/ranch testing. Annual DSA, pre move Wildlife testing

11 Brucellosis Rules Combined Brucellosis/TB proposed rule Publish in the Federal Register Published in December 2015 USDA is reviewing public comments and feedback Summary Brucellosis: Current Status Final Rule & Combined TB/Brucellosis Proposed Rule Brucellosis Surveillance Plan Questions? 11

12 Name of Speaker Title U.S. Department of Agriculture Animal and Plant Health Inspection Service Veterinary Services Phone number address US cattle slaughtered (NASS 2015) 29 million head (down 5% from 2014) 54% steers, 26% heifers, 20% cows & bulls Average weight = 1360 lbs. US Adult cull cattle 5.5 million head (3 million dairy & 2.5 million beef) US Fed cattle 23 million head Program Numbers (thru August 2016) Texas Brucellosis Surveillance Lab 628,305 samples from 2 plants 71 FPA positives (.011% FPs or % Sp) with no cases 11 cases / 100,000 samples responder rate Average FPA Positive result = 51mPs

13 Adults killed = (3 million dairy & 2.5 million beef) 5.5 Total US Cattle 2016 (92 million head) % slaughtered of Total = 31.5% Adult slaughtered = 6.0% Fed/Fats slaughtered = 25.5% Not slaughtered = 68.5% Total US Slaughter Cattle 2015 (29 million head) Steers = 54% Adults = 20% Heifers= 26% Average weight = 1360 lbs. Non slaughtered Adults slaughtered Feds/Fats slaughtered Steers Heifers Adults Reduced Brucellosis Blood collection Used to collect blood on 95% of adults killed annually. These are legacy members of our national herd. Now collect 31% of adults culls Adults killed = (3 million dairy & 2.5 million beef) 5.5 Total US Cattle 2016 (92 million head) Note: But the US can still detect 2 cases per million 95% confidence at this level of slaughter surveillance Program Numbers (thru August 2016) GYA Brucellosis Surveillance Labs State and local/private labs Approved by USDA to test for brucellosis Don t have numbers on those laboratories Non slaughtered Adults slaughtered Feds/Fats slaughtered

14 2015 Brucellosis Affected Herds Bison, Test and Remove Idaho ( Montana Bison, Test and Remove Bison, Test and Remove Wyoming 2 affected beef herds quarantine released 3 bison herds remain under test and remove herd plans from 2011 and 2012 The ID & WY bison herds may be released from quarantine in 2016 All GYA States remain classified as Class Free for bovine brucellosis. Overview Brucellosis: Current Status Combined TB/Brucellosis Proposed Rule Brucellosis Surveillance Plan Utah Program Numbers Market Cattle Identification (MCI) Surveillance: 2015 Program Numbers Certified Brucellosis Free Herds ~ 1,726,675 head of cattle tested National surveillance facilities ~ 513 herds ~ 123,506 GYA cattle tested Vaccination ~ 861,138 OCV ~ 228,866 AV

15 2016 Brucellosis slaughter traces by State