The epidemiology of Mycoplasma hyopneumoniae

Eric BushUSDA:APHIS:VS

FDA:CVMSwine Mycoplasma Pneumonia Workshop

Kansas City, MOMarch 6, 2002

Objective: Respiratory disease Porcine Respiratory Disease

Complex (PRDC) Prevalence of primary pathogens Severity of condition

• mortality due to respiratory illness• age of onset in grower/finisher• course of treatment

Extent of control measures and their relation to prevalence and severity

Swine 2000

Swine 2000 study design NASS General Swine Farm Report

• June 1 – July 14, 2000• n=2499 respondents

VS Initial VMO visit• August 21 – November 3, 2000• n=895 respondents

VS Second VMO visit• December 1, 2000 – March 15, 2001

Ref: USDA:APHIS:VS. Part I: Reference of Swine Health and Management in the United States, 2000. Fort Collins, CO:NAHMS; 2001 August. Swine 2000

Objective: Serum bank Create national serum bank

Epidemiological description of endemic pathogens• prevalence• distribution• risk factors

Natural history of emerging diseases• time of emergence• epidemiological description

Swine 2000

Swine 2000 study design Blood collection Voluntary participation Collection from sows/gilts

• Max of 30 samples• Quota sampling by parity

Collection from finishers • Max of 15 samples• Across pens (max of 10 pens)• Must be 20 weeks or older

Shipped overnight on ice to NVSL.

Swine 2000 study design Blood collection Testing:

• PRRS - ELISA test at NVSL. • Mycoplasma – Tween20 ELISA test at ISU

(Pfizer).• Mycoplasma - IDEXX ELISA test at

BI/Vetmedica.• SIV - HI test at WI (Schering-Plough).

Serum banked for further use.• 5 of 8 sets left

Swine 2000 Blood collection Finishers only 200 Breeding only 111 Both 195

Total 506 sites----------------------------------------

14,328 samples collected from 506 sites. • 8466 sow/gilt samples from 306 sites• 5862 finisher samples from 395 sites.

Mycoplasma (ISU) results Site prevalence:

Finishers: 82.3% Breeding: 94.8%

Animal prevalence Finishers: 48.9% Breeding: 38.3%

Swine 2000

Any questions

How does site prevalence vary…

By region? By type of site? By size of site? Vaccine status of site? By visit blood collected (season)?

Site prevalence, by type Finishers only 77.5% Breeding only 97.3% Both 97.4%

All sites 89.5% sites

Site prevalence, by total inventory

<2000 2000-9999 10,000+

83.9 80.6 80.8

<2000 2000-9999 10,000+

93.1 98.1 92.3

Swine 2000

Sites with breeding females

Sites with finisher

Site prevalence, by vaccination status

Do vaccinate Don’t Vaccinate

88.4 77.1

Do vaccinate Don’t Vaccinate

97.8 93.5

Swine 2000

Sites which vaccinate breeding females

Sites which vaccinate finishers

Site prevalence, by visit (season)

First visit Second visit

88.5% 79.2%

First visit Second visit

76.9 94.9

Swine 2000

Sites with breeding females

Sites with finishers

What about the prevalence within sites (herds)?

How does it vary by pig type?

Distribution of sites by number of positive finishers

7063

45 49

7890

0

40

80

120

0 1-3 4-6 7-9 10-12 13-15

Number of positive finishers

Swine 2000Mean = 48.9%

Distribution of sites by number of positive breeding females

16

36

5145

52

3626

15 11 10 8

0

30

60

90

0 1-3 4-6 7-9 10-12

13-15

16-18

19-21

22-24

25-27

28-30

Number of positive breeding females

Swine 2000Mean = 37.4%

How does animal prevalence vary…

By region? By size of site? By gender of finishers? By parity of breeding females? Vaccine status of animal?

56.9%41.7%

42.7%36.1% 47.7%

37.0%

51.2%38.5%

Animal prevalence, by total inventory

<2000 2000-9999 10,000+

50.2 47.9 45.3

<2000 2000-9999 10,000+

36.5 38.6 47.9

Swine 2000

Percent breeding females that were positive

Percent late finishers that were positive

Finisher prevalence, by gender Gilts 46.0% Barrows 50.8%

All late finishers 48.9%

Animal prevalence, by vaccination status

Vaccinated Not vaccinated

56.1 43.3

Vaccinated Not vaccinated

49.8 32.1

Swine 2000

Percent of vaccinated sows/gilts that were positive

Percent of vaccinated finishers that were positive

Other mycoplasma data Prevalence of mycoplasma as

reported by respondents Vaccination practices Other control strategies

Prevalence of selected diseases in nursery pigs, by herd size

0 20 40 60 80 100

Strep suisStaph hyicus

PMWSPRRS

SIV (new)SIV (old)

MycoplasmaH. parasuis

APP

Percent sites

<2000 2000-9999 10,000+

Swine 2000

Prevalence of selected diseases in grow/finish pigs, by herd size

0 20 40 60 80 100

ErysipelasI leitisPMWSPRRS

SIV (new)SIV (old)

MycoplasmaAPP

Percent sites

<2000 2000-9999 10,000 +

Swine 2000

Mycoplasma vaccination – breeding females

0

20

40

60

80

100

<250 250-499 500 +

Breeding female inventory

Perc

en

t sit

es

Killed Autogenous DK

15.4%

43.6% 46.2%

Swine 2000

Mycoplasma vaccination – breeding females

 

 

Prior to entry

At entry

In the herd <250

250-499 500 +

Yes Yes Yes 23.1 14.0 26.1

Yes Yes No 3.4 15.6 24.5

Yes No Yes 5.3 5.9 6.2

No Yes Yes 7.8 11.1 0.0

Yes No No 42.2 41.4 18.7

No Yes No 6.0 8.7 24.5

No No Yes 12.2 3.3 0.0

Number of mycoplasma vaccinations received by breeding females

60.4 53.4 43.2

16.5 32.630.7

23.1 26.114.0

0%

20%

40%

60%

80%

100%

<250 250-499 500 +

Breeding female inventory

Perc

en

t of

vaccin

ate

d

sit

es

One Two Three

Swine 2000

Percent sites using vaccine to control mycoplasma in weaned market pigs, by herd size

2

33.3

9.1

10.6

60.8

22.5

0.6

55.3

42.2

0 20 40 60 80 100

Vx >70lbs

Vx le 70lbs

Vx sows/ gilts

Percent sites

<2000 2000-9999 10,000 +

Swine 2000

Number of mycoplasma vaccinations received by weaned market pigs

66.1

34.5 44.8

17.2

44.1 31.2

16.7 21.4 24

0%

20%

40%

60%

80%

100%

<2000 2000-9999 10,000

Total inventory

Perc

en

t of

sit

es

None One Two

Swine 2000

Mycoplasma vaccination – age weaned market pigs are vaccinated (weeks)

Dose <20002000-9999 10,000 +

1st & only 7.4 7.7 6.9

Swine 2000

Mycoplasma vaccination – age weaned market pigs are vaccinated (weeks)

Dose <20002000-9999 10,000 +

1st & only 7.4 7.7 6.9

1st of two 3.2 4.1 3.4

Swine 2000

Mycoplasma vaccination – age weaned market pigs are vaccinated (weeks)

Dose <20002000-9999 10,000 +

1st & only 7.4 7.7 6.9

1st of two 3.2 4.1 3.4

2nd of two 6.2 7.4 9.3

Swine 2000

Strategies employed to control mycoplasma in weaned market pigs, by herd size

0 20 40 60 80 100

Any of aboveRx pen/ air space

Rx ill pigsAIAO Nursery

AIAO farrowWean w/ Abx

MEWEarly Wean

Percent sites

<2000 2000-9999 10,000 +

Swine 2000

Acknowledgments National Agricultural Statistics Service (NASS) NAHMS Design and Implementation team State and Federal Veterinary Medical Officers, VS field APHIS: National Veterinary Services Laboratories (NVSL) ARS: Russel Research Center ARS: Eastern Regional Research Center ARS: National Animal Disease Center U.S. Food and Drug Administration (FDA-CVM) National Pork Board American Association of Swine Veterinarians (AASV) Pfizer Boehringer Ingelheim Vetmedica IDEXX Laboratories, Inc. Schering-Plough Iowa State University The Ohio State University University of Illinois University of Tennessee University of Wisconsin – Madison

Swine 2000

For more information:

Eric BushUSDA:APHIS:VS-CEAH555 S HowesFort Collins, CO. 80521(970) 490-8000

Eric.J.Bush@aphis.usda.govOr search for “NAHMS swine” on the web.