By John Maday and Jennifer Shike
For a special occasion, you might splurge on a custom suit. If you are rolling in cash, maybe a custom-built Italian sports car fits the bill. For veterinarians and livestock producers though, a custom vaccine isn’t an extravagance, but rather another tool in the box for addressing new or uncommon strains of livestock pathogens.
FDA-licensed commercial vaccines and bacterins from reputable suppliers generally provide safety and efficacy if handled and administered properly, and can offer cross-protection against pathogen strains not used in production of the vaccine. However, when efficacy seems to decline, a custom or autogenous vaccine, containing antigens specifically targeted toward new or unusual strains of pathogens that can emerge locally, could provide a better, more specific immune response.
In the short term, diagnostic testing provides a scientific basis for treatments and management decisions to address livestock diseases. In the longer term, identifying the pathogens involved helps veterinarians and producers design more effective vaccine protocols and other preventive strategies. At Newport Laboratories, the process reaches further, with tests to identify and multiply specific isolates involved in an outbreak, for use in developing autogenous vaccines, targeting those exact viral or bacterial strains. Diagnostic testing in this way becomes more proactive, rather than reactive.
“Diagnostics show us what’s really going on – instead of just shooting from the hip clinically,” says Randy Shirbroun, DVM, and ruminant business unit director at Newport Laboratories. “A key component is making sure we have the right isolate. Quality control measures take place all along the way with testing to make sure the process is coming along well and that there aren’t any glitches.”
The following outlines the steps involved in the Newport Laboratories, Inc. custom-made vaccine manufacturing process, including sampling, diagnostics and post-administration follow up.
This example explores the development of a custom bacterin for protection against pinkeye, associated with Moraxella bovis and Moraxella bovoculi in cattle. The description represents a typical scenario, but the timeline and protocol can vary depending on the situation.
Production Process for a Custom Bacterin
Step 1: Conversation with Herd Veterinarian and Sample Collection (5 to 10 business days)
- Herd veterinarian discusses herd health challenges with Newport Laboratories team member.
- Herd veterinarian collects samples, completes necessary submission forms and ships samples to Newport Laboratories using free diagnostics shipping kit.
Step 2: Isolation and Identification (3 to 5 business days)
- Samples are streaked on a plate and cultured overnight. Individual colonies are identified and re-cultured until a pure isolate is attained.
- Isolates are analyzed by Matrix-assisted laser desorption/ionization (MALDI-TOF) to identify the specific pathogen. MALDI-TOF is an ionization technique that uses a laser energy absorbing matrix to create ions from large molecules with minimal fragmentation.
- Depending on direction from the herd veterinarian, additional tests, such as PCR, may be added to the order and performed to test for viral or mycoplasma antigens. If the PCRs indicate viral or mycoplasma organisms are present in the sample, additional time would be required to culture, identify and attain a pure isolate for possible production.
Step 3: Sequencing and Selection (7 to 14 business days)
- Optional sequencing can be performed using MLST to identify specific strains present.
- Results are cross-referenced against samples previously submitted from the herd of origin to identify those best suited for custom-made vaccine creation.
- If performed, sequencing report is submitted to herd veterinarian along with a recommendation from Newport Laboratories on the isolate(s) that should be included in the custom-made vaccine. Herd veterinarian discusses report and recommendation with Newport Laboratories team member and settles on desired order.
Step 4: Order Submitted and Received by Newport Laboratories (Up to 5 business days for order processing)
Step 5: Vaccine Manufacturing (33 to 48 calendar days, made up of the following step)
- Antigen growth and inactivation (16 to 27 days)
- Concentration (Eight days)
- Batching (Five to Nine days)
- Bottling (Four days)
Step 6: Final Quality Control (14 calendar days)
Step 7: Ship to Customer (5 to 7 business days)
Step 8: Administration and Follow Up (Upon receipt by herd veterinarian to approximately three months following administration*)
- Herd veterinarian administers custom-made vaccine.
- A Newport Laboratories team member follows up with the herd veterinarian to discuss results and determine if further action is needed. *Note, timing for follow up is dependent on various factors, including the type of pathogen and when the custom-made vaccine is administered.
Autogenous Vaccines: Key Take-Home Points.
- Modern genetic technologies including next-generation genome sequencing, Multilocus sequence typing (MLST) and PCR (polymerase chain reaction) testing allow scientists to accurately identify specific pathogen serotypes, virulence factors and antimicrobial susceptibility.
- Viruses and bacteria continuously evolve, and the prevalence of some strains can increase while others decline. With continuous testing, isolation and analysis, a custom-vaccine manufacturer can respond quickly with products that reflect the strains currently circulating in livestock herds.
- Several common cattle pathogens, such as Mannheimia haemolytica, Histophilus somni and Pasteurella multocida have, in Newport’s testing results, shown trends toward decreasing susceptibility to some antibiotics.
- Pinkeye in cattle can involve strains of Moraxella bovis, Moraxella bovoculi, or some combination of the two bacteria species. M. bovoculi has become more prevalent in many cases in recent years. When pinkeye remains a problem in herds in spite of good fly control and use of commercial vaccines, an autogenous vaccine can provide more targeted immunity.
- Custom vaccines can play a key role in addressing emerging diseases by reducing the time from sampling and isolation to field application. Veterinarians and producers also use autogenous vaccines to address “orphan” diseases, which cause economic losses in some herds but are not sufficiently common to support investment in developing commercial vaccines.
- Appropriate sample collection, handling and shipping methods are critical for good diagnostic-testing results. The Newport Laboratories website offers sampling guidelines for cattle and pigs.