key: cord-0040344-cw5wnc3h
authors: Long, Patrick O.
title: Camelid Vaccinations
date: 2013-12-06
journal: Llama and Alpaca Care
DOI: 10.1016/b978-1-4377-2352-6.00003-1
sha: 254dcc0ee123491a809716589aba5372d6e8f621
doc_id: 40344
cord_uid: cw5wnc3h

nan

Vaccination protocols for camelids vary widely in the United States. Variations occur even regionally. Establishing a rational immunization protocol for clients can be a challenging endeavor for most practitioners. Vaccination protocols should be based on potential exposure, prevalence of disease in your local area and susceptibility of camelids to these diseases. Unlike some other species (e.g., feline, equine) in the United States, currently, no established guidelines exist for vaccination of camelids.

Vaccination programs may be designed for individual farms on the basis of local disease incidence, potential exposure from neighboring farms, and animal movement to and from the farm. At present, many camelid farms follow what successful breeders use in other parts of the country without regard for regional concerns. Although many vaccines are currently used in the United States, not all camelids need all of the vaccines discussed below. As with other animal species, vaccine programs should be tailored for individual producers and their current needs.

It should be noted that currently no vaccines are labeled for use in camelids and that all usages are considered off-label. Use of vaccines should also be considered in light of the pregnancy status of camelids. Given the high incidence of congenital defects in camelids, some authors caution against using any unnecessary medications, including vaccines, in the first trimester of pregnancy. Vaccines that could be considered in setting individual farm programs are discussed below.

Vaccines against Clostridium perfringens types C and D and C. tetani (CDT) should be considered "core" vaccines for camelids. Although recommendations vary with regard to time of first vaccine, these vaccines are typically given twice at 3-to 6-week intervals in the first year and then boostered annually after the primary series. It is known that camelids are susceptible to these pathogens, and several studies have shown antibody response after two injections. 1 In some high-risk areas, the primary vaccines are started at age 2 to 5 days. Another protocol would be to start the vaccination series at age 3 to 4 months in crias that obtained good passive transfer and whose dams were previously vaccinated. Booster vaccines are generally recommended for animals undergoing surgical procedures or for animals that have suffered open wounds from trauma if the last vaccine was given more than 6 months ago. Many practitioners recommend boosting CDT vaccines 4 to 6 weeks prior to birthing in pregnant dams. Be cautious of rough handling or excessive excitement during the vaccine administration procedure, as camelids are considered prone to stress-induced abortions.

Multivalent clostridial vaccines, which include those against Clostridium septicum, C. sordelli, C. novyi, C. chauvoei, and C. haemolyticum, may be considered if the risk is present, especially in relation to complications of snake envenomations. Ideally, these vaccines should not be used in pregnant dams but could be used in the window postpartum period and before rebreeding. Recommendations for these products would be the same as those for the CDT program outlined above. Injection site reactions may occur with these products, so injection sites should be checked a few weeks after administration.

Fortunately, anthrax has rarely been a problem in camelids, but one might be tempted to vaccinate in an endemic area. Unfortunately, use of an anthrax spore vaccine in young llamas resulted in some deaths. 2 

Leptospirosis has been known to occur in camelids and may cause liver or kidney damage and abortion. In endemic areas, vaccination against leptospirosis would appear prudent. Camelids have been shown to mount an immune response, which, however, has been reported to be of short duration. 3 Multiserovar products containing L. canicola, L. grippotyphosa, L. hardjo, L. icterohaemorrhagiae, and L. pomona, which are approved for use in sheep and cattle, are commonly used in camelid herds. Two primary vaccinations are typically used, followed by semiannual boosters in the author's practice.

Confirmed cases of rabies in camelids have been reported, so vaccination should be considered in endemic areas even though no currently available product has been approved. Rabies vaccines have been used in camelids in endemic areas. Various protocols have been recommended. Recommendations based on a recently completed study consist of one injection at age 3 to 4 months followed by yearly boosters (Dr. Julie Dechant, personal communication). Killed products licensed for other large animal species would be Part 1 • Herd Health recommended. Small animal products or modified live vaccines would not be recommended.

Several studies on the efficacy of West Nile (WNV) vaccines in camelids have been completed. Camelids have been shown to be susceptible to WNV infection, with death resulting in many cases. Research has shown that three doses of the Fort Dodge Innovator vaccine given at 3-week intervals will provide antibody response in 95% of animals vaccinated. 4 If this vaccine is used, the third vaccine or the subsequent yearly booster should be given approximately 1 month prior to peak mosquito exposure. Once WNV has been established in an area, likely only the naive young and immuno-compromised would need vaccination.

Eastern equine encephalitis (EEE) has been reported to be the cause of death of several camelids in the eastern parts of the United States in recent years. Vaccine trials have been conducted, and no adverse effects from a killed multivalent product used in alpacas have been reported. 5 Currently, no EEE-only vaccines are available. Most currently marketed products also contain western and Venezuelan equine encephalitis and or equine influenza vaccines. Recommendations for EEE vaccination schedule would be similar to the WNV protocol. Three doses at 4-week intervals should be given in the first year, and yearly boosters should be given approximately 1 month prior to peak mosquito exposure. 6 

Equine Herpes Virus 1 (EHV-1), a virus primarily causing infection in horses and other Equidae, has occasionally been reported in camelids as well. 7, 8 If camelids are being housed with horses (or zebras) or are in nose-to-nose contact with horses, this vaccine should be considered. Killed vaccines are recommended, with boosters given at 6-month intervals.

Although bovine viral diarrhea virus (BVDV) infection has recently caused concern and has led to testing in camelid herds in the United States, vaccination against this disease is not recommended. Vaccination will make detection and eradication of this disease much more difficult. Commercial cattle vaccines are available, but they have not demonstrated good efficacy in eliminating persistent infection in cattle and thus have no place in camelid herds.

Coronaviruses have been implicated in gastrointestinal and respiratory infections in camelids. 9, 10 Although not indicated for all animals, in some situations, the use of a coronavirus vaccine would be indicated. Coronavirus is a common pathogen causing neonatal diarrhea on many farms, and in these situations, the use of a vaccine, in conjunction with other husbandry practices (ensuring adequate passive transfer and improved hygiene on the farm), may be indicated. Oral administration of a modified live bovine rotavirus or coronavirus vaccine in neonates before nursing could be used in these situations. 11 Diarrhea in show animals during the 2008 show season was widely reported across the United States. Many of these were confirmed to have been caused by coronavirus. Although most of these were self-limiting and resolved within a few days, the diarrhea typically affected other animals on the farm, even with the farms practicing adequate biosecurity measures. Vaccination of show string animals in high-risk situations may be considered.

Antibody response to the epsilon toxin of Clostridium perfringens following vaccination of Lama glama crias

Vaccination-related anthrax in three llamas

Serologic response of llamas to a commercially prepared Leptospirosis vaccine

Humoral response to West Nile virus vaccination in alpacas and llamas

Humoral response to an equine encephalitis vaccine in healthy alpacas

Proceedings of the International Camelid Health Conference for Veterinarians, College of Veterinary Medicine

Experimental equine herpesvirus-1 infection in llamas (Lama glama)

An epizootic of blindness and encephalitis associated with a herpesvirus indistinguishable from equine herpesvirus I in a herd of alpacas and llamas

Identification of a novel corona virus possibly associated with acute respiratory syndrome in alpacas (Vicugna pacos) in California

Potential pathogens in feces from unweaned llamas and alpacas with diarrhea

Differential diagnosis of diarrhea in camelid crias. Proceedings of the International Camelid Health conference for Veterinarians