One Revolutionary 3-in-1 Vaccine

CIRCUMVENT CML is the newest addition to the CIRCUMVENT vaccine family, providing protection against porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae and Lawsonia intracellularis.

Just one injection covers three major profit-robbing diseases.

Choosing a PCV2 vaccine that also protects against M. hyopneumoniae and L. intracellularis can help protect the bottom line further by:

Cutting down on labor and waste

Increasing feed savings1

Providing a long DOI2

Reducing late finishing mortality due to PCVAD1

The C in CML: Porcine circovirus type 2

A PCV2 vaccine matters in protecting pigs and profitability. It’s the first step in the development of porcine circovirus-associated disease (PCVAD).

PCVAD can:

  • Increase mortality, culls and treatments1
  • Negatively impact average daily gain and feed conversion1
  • Increase the severity of coinfection from PRRS, Mycoplasma hyopneumoniae and influensa A virus3-5

PCVAD disease progression from time of exposure

Day 0

Initial Exposure

Initial Exposure
to PCV2

Days 0-12

After Exposure

Initial Infection
Undetectable viremia

Days 12-20

After Exposure

Breakout Infection
Detectable viremia, shedding, lymphoid depletion

Days 20-120+

After Exposure

Pigs either resolve, are left with chronic lymphoid inflammation or the disease proves fatal

CIRCUMVENT CML is a proven porcine circovirus vaccine that significantly reduces PCVAD after a PCV2 challenge.

  • The amount of virus in the blood was 99% lower in pigs vaccinated with CIRCUMVENT CML2
  • Pigs vaccinated with CIRCUMVENT CML also had significantly higher antibody levels than unvaccinated pigs2

The M in CML: Mycoplasma hyopneumoniae

Mycoplasma hyopneumoniae is a common cause of pneumonia in pigs. It often leads to chronic lung infections – causing reduced average daily gain and decreased feed efficiency.7 CIRCUMVENT CML, from the CIRCUMVENT vaccine family, is a safe and effective prevention.

Vaccinating with CIRCUMVENT CML is proven to significantly reduce lung lesions after an M. hyopneumoniae challenge2

Lung lesions in the group vaccinated with CIRCUMVENT CML were nearly half that of unvaccinated pigs after challenge at 10 weeks of age.2

The L in CML: Lawsonia intracellularis

Lawsonia intracellularis causes ileitis, an enteric disease that much like circovirus and M. hyopneumoniae, decreases average daily gain and feed efficiency. As a result, much more feed is required for pigs to reach market weight. Ileitis isn’t always easy to spot either – 94% of herds with no visible signs are found to have subclinical ileitis.8,9

Protecting gut health is critical, especially in young pigs. Proven effective against L. intracellularis, CIRCUMVENT CML is up for the task.

Pigs vaccinated with CIRCUMVENT CML:

  • Had mean intestinal lesion scores (length and severity) that were nearly half that of unvaccinated pigs2
  • At necropsy, had intestinal bacteria levels that were 90% lower on average than unvaccinated pigs2


bacteria levels2



1. Jacela JY, Dritz SS, DeRouchey JM, et al. Field evaluation of the effects of a porcine circovirus type 2 vaccine on finishing pig growth performance, carcass charateristics, and mortality rate in a herd with a history of porcine circovirus-associated disease. J Swine Health Prod. 2011;19(1)10-18.
2. Data on file, Merck Animal Health.
3. Saade G, Deblanc C, Bougon J, et al. Coinfections and their molecular consequences in the porcine respiratory tract. Vet Res. 51, 80 (2020).
4. Fan P, Wei Y, Guo L, et al. Synergistic effects of sequential infection with highly pathogenic porcine reproductive and respiratory syndrome virus and porcine circovirus type 2. Virol J. 2013 Aug 26;10:265. doi: 10.1186/1743-422X-10-265. PMID: 23971711; PMCID: PMC3847690.
5. Opriessnig T, Thacker EL, Yu S, et al. 2004. Experimental reproduction of postweaning multisystemic wasting syndrome in pigs by dual infection with Mycoplasma hyopneumoniae and porcine circovirus type 2. Vet Pathol. In Press.
6. Merck Animal Health Technical Services Bulletin: Efficacy of Circumvent® CML compared to controls in a PCV2d/PRRSV Co-Infection Challenge Study.
7. Thacker EL and Thacker BJ. Mycoplasma hyopneumoniae and PRRS in the finisher. 1999 American Association of Swine Practitioners, 483-485.
8. USDA. 2007. Swine 2006, Part II: Reference of swine health and health management practices in the United States. 2006. USDA:APHIS:VS, CEAH. Fort Collins, CO.#N479.1207.
9. Armbruster GA, et al. Review of Lawsonia intracellularis seroprevalence screening in the United States. June 2003 to July 2006. Proceedings of the 38th Annual Meeting of the American Association of Swine Veterinarians. 2007.