Vaccine Strategies for Livestock and Poultry
Autologous and Autogenous Vaccines
Apart from licensed vaccines, autogenous and autologous vaccines provide additional protection in controlling infectious diseases and maintaining livestock health. These vaccines are also most useful when there are no available licensed vaccines for the target pathogen or species.
Autologous vaccines are veterinary biologics prepared using pathogens and/or antigens isolated from an infected animal and used only for the particular animal.
Autogenous vaccines are veterinary biologics prepared using pathogens and/or antigens isolated from infected animals in a particular farm. These are then administered for the prevention of the disease for the same farm animals or nearby farms. In case of administration of nearby farms, there should be an epidemiological linkage between the farms to establish application of the same autogenous vaccine.
| Countries where production IS ALLOWED* | Countries where production IS NOT ALLOWED | |
|---|---|---|
| Bacterial inactivated autogenous vaccines |
ASEAN Australia Canada All EU member states South Africa United States |
|
| Viral inactivated autogenous vaccines |
ASEAN Australia Belgium Canada Czech Republic Germany Hungary Italy Poland South Africa UK United States |
Croatia Denmark Finland France Iceland Norway Portugal Slovakia Spain Sweden |
| Live-attenuated vaccines** |
ASEAN Australia South Africa |
Canada All EU member states USA |
In Singapore, production of autogenous vaccines (classified as veterinary biologics) is regulated under Animal and Birds Act. A license to possess veterinary biologics should be obtained from AVS and NParks, which sets forth requirements including product testing to demonstrate stability, purity, sterility, and toxicity tests in animals.
Autogenous vaccines are approved to meet specific and immediate need when a disease is associated with a new pathogenic organism, when approved veterinary biologics are not effective in controlling current disease problem (when available vaccines lost their efficacy), or when approved veterinary biologics are not available to prevent or control the disease situation.
Autogenous Vaccine Workflow
Mucosal vaccines
The goal of mucosal vaccines is to prevent infection of the pathogen through the mucosal surfaces instead of preventing the onset of the disease. Most pathogens enter through mucosal surfaces which should be protected by mucosal immunity.
Mucosal surfaces include nasal, sublingual, oral, rectal, vaginal, pulmonary, and trans-dermal. Choosing the right mucosa to administer the vaccine is critical for eliciting the effective immunity. Several theories have shown that mucosal sites are linked; suggesting the administration of vaccine at one mucosal site induces also protection at other mucosal sites.
Intranasal vaccines
Nasal vaccination in mice have been shown to elicit immune response at different mucosal sites. This is further achieved through the use of adjuvants such toxins (cholera or heat-labile enterotoxin).
Oral vaccines
The main challenge in oral antigens is the delivery and prevention of oral tolerance. There is a delicate balance for virulence such that it should not be too virulent that it causes the disease nor too attenuated that the immune system cannot mount a response.
