United States virus

Vaccination and Isolation of Felis catus and Insecticide Control of Ctenocephalides felis for Prevention and Abatement of United States ebolavirus

Overview

      To inhibit the spread of disease, all the links in the disease cycle must be broken. Included in these links are the pathogen, vector, reservoir, and host. Each plays an important part in perpetuating the disease. Our final control plan to stop and prevent  United States virus will include the use of both vaccination on Felis catus, the domestic cat, and insecticides on Ctenocephalides felis, the cat flea.

Vaccination and Isolation:

      In our preliminary control efforts, the previously made vaccine was 94% effective in preventing new cases from arising in Los Angeles, California. Los Angeles was a hub of United States virus, so this lowering of cases is significant in control efforts. There was some negative feedback from the general public concerning the vaccination’s effects on the cats and cattle in the area, yet the 94% prevention for an 100% fatal disease is worthy enough to continue with the procedure.

      The vaccination works by making the domestic cat, which is the reservoir, resistant to the pathogen, United States ebolavirus (UEBOV), breaking two links in the cycle. The first link is between the pathogen and the reservoir, while the second is the transmission of the pathogen from the reservoir to the vector. With the vaccination of domestic cats, there will be less reservoirs for UEBOV to infect and proliferate in. Ebolaviruses replicate by taking over hosts cells, replicating, and budding out mature cells (Marzi et al. 2012). If the reservoir’s cells are resistant, the pathogen has nowhere to replicate and the cycle will end there. This also has the added bonus of stopping the transmission of the pathogen to the vector, the cat flea. Since less domestic cats will be infected with the pathogen, there will be less chance that the cat flea will become infected. As a result, even if a vaccinated domestic cat does become infested with fleas, there will be no danger of the flea transmitting UEBOV to humans or another domestic cat.

      If the cat is already infected with the UEBOV however, then the cat will be put into quarantine with supportive care until the infection passes or the cat succumbs. Removing an infected cat from the environment will further lower the chance that more cat fleas will get infected and then spread the disease. This isolation breaks the transmission of the pathogen, from the reservoir, to the vector.

Materials/Methods:

       The mandate from the preliminary plan, dictating that all domestic cats must be vaccinated, will be sent to areas of Seattle, Washington, Homestead and Miami, Florida, Las Vegas, Nevada, and Billings, Montana. Fifteen boxes filled with 100 each of syringes, needles, and vaccine serum will be sent to all the veterinary clinics, animals shelters, and animal control centers in these areas. Los Angeles, California already has the procedure for vaccinations in progress, but six additional boxes of 100 of each of their materials such as the vaccine serum, needles, or syringes will be sent. In all locations, 10 boxes of blood serum vials will be sent, with each box containing 100 vials.

       The cats will be injected between their shoulders with 1 mL of the vaccine serum (Aberdein et al. 2007). Once the cat is vaccinated, the veterinarian giving the vaccination will signed a document stating that the cat is vaccinated and the date of the vaccination. These forms will be standardized and made by us. Each place that is giving vaccinations will have a stack of 1,500 sent to them. If any of the aforementioned materials dwindles down to one box, then the clinic, shelter, or control center can email us through our web page and request more.

       Animal control centers and shelters will vaccinate any cat that comes into their property. Animal control centers will also work to remove all feral cats from the streets using 10 cat traps so that wild reservoirs will not be an issue. Even if domestic cats are all vaccinated, feral cats could still infect vectors with the pathogen and these could then get handled by humans. The humans in this instance would then get infected with United States virus. Residents of the area will be advised to not go near any feral cats or cat traps and call animal control for the removal of any feral cats they might see in the area.

       If any of the cats come in with signs of illness to a vaccination center or from animal control, the veterinarian is to take a blood sample, analyze it, and see if the cat is infected with UEBOV. If the cat is not infected, but is sick, the owner/shelter will have to take the cat back to wherever it is staying, since vaccines only work effectively for prevention when the cat is healthy. The veterinarian may prescribe medications for these separate illnesses. If the cat is infected with UEBOV, then the cat will have to immediately be put into a pet carrier and transported in a secure vehicle to quarantine rooms at the veterinarian’s clinic or a local animal hospital. We do not want this cat having contact with cat fleas or other cats that it could transmit the pathogen to. These rooms will be secured and blocked off to anyone who does not need to be in contact with the animal. Impermeable traps will cover the room and reach 1 to 2 feet off the ground. In quarantine, the cat will be treated with supportive care by a veterinarian and be monitored (Spengler et al. 2015). Hopefully the cat recovers and can be returned back to its owner.

Insecticide:

      Insecticides can be used to break the links for pathogen transmission from infected reservoir to uninfected reservoir and from infected reservoir to host. This works by eliminating all the vectors needed to transmitted the disease from the infected to those not infected, such as another reservoir or host. In this case, killing all the cat fleas will prevent them from picking up the pathogen and infecting other domestic cats or humans. Insecticides are needed in order to reduce the flea population in neighborhoods parks and homes that are infested with infected fleas. For these outside neighborhood parks and homes, we decided that an Insect Growth Regulator (Archer IGR) containing Nylar is best to use tank mixed with the odorless aerosol insecticide Permethrin Pro using a hose-end sprayer.

       The Archer IGR with Nylar will target the eggs and larvae. The Archer IGR breaks the life cycle of immature flea stages inhibiting them to reach the adult stage (Professional Pest Control Products 2016). The active ingredient in Archer IGR is Nylar and is a photostable material meaning even through light exposure, it still retains its integrity instead of degrading as a product which is perfect for the outdoors. Permethrin Pro insecticide will target the adult fleas. This insecticide contained at least 36% active ingredients and must be sprayed using a hose-end sprayer for successful outdoor application. The high concentration of Permethrin Pro allows less product to be used per application.

      For best use, 1 ounce of Archer IGR and 1 ounce of Permethrin SFR will be sprayed per 1,000 square feet. Archer IGR spray lasts for 30 days outdoors and will result in elimination of a larvae and eggs. Permethrin SFR will target the adults. This method will however not eliminate the pupae stage of fleas because “flea pupae are water-tight and are not affected by [the] spray” (Professional Pest Control Products 2016); therefore, another application of the IGR and insecticide will be needed two weeks after the initial application. Flea kits will be sent out with the accurate amount needed depending on square feet coverage. These kits will include the Permethrin SFR Insecticide, the IG Regulator as well as a 20 gallon hose-end sprayer and will cost us roughly $70 per quart of Permethrin SFR and 4 ounces of IGR (Professional Pest control Products 2016). The kit products “are approved for spraying outdoors and inside homes, but” (Professional Pest Control Products 2016) must be carefully used. Animals and humans should not be sprayed nor allowed around sprayed areas until treated areas are dried out.

Materials/Methods:

The materials needed are:

• Garden hose

• Hose end sprayer (approved Dial Sprayer for insecticide use)

  • No-clog sprayers are too inaccurate for adequately spraying insecticide for fleas

• Insecticide (Permethrin SFR and Archer)

  • Harmful if swallowed, inhaled, or absorbed through skin, so avoid contact with eyes, skin and clothing

  • Wear protective gear when spraying

The step by step method is:

• Pour 5 oz of  one of the insecticides into hose end sprayer

  • Permethrin SFR

  • Archer with Nylar, an IGR or insect growth regulator will be used

• Set dial of hose end sprayer on 1 oz or less

• Spray lawn in even, sweeping motions

  • For outdoors, at least 3 gallons of solution per 1,000 sq ft is needed

• Repeat process with other insecticide.

• Prevent any people or pets from having contact with the sprayed area until it dries

  • Do not apply directly to water because it is highly toxic to fish and aquatic invertebrates

• Reapply after 14 days if necessary

• Understand that fleas do not disappear immediately after spraying

  • Severe infestations can take up to 8 months of 14-day treatment cycles to be resolved

Implementation

Vaccination/Isolation:

      Each veterinary clinic will give vaccinations by appointment, and the owner will have no say whether the cat is allowed to get vaccinated. For the animal control centers and shelters, they will vary the days that they will be giving vaccinations. As a general guideline for now, the vaccinations for animal control will be given out on Monday and Wednesday, while the animal shelters could give out vaccines on Tuesday and Thursday. These will be administered by any veterinarians that work for or are associated with the centers. The hours for these vaccination operations will be from 8 am to 11 am on the first day and 1 pm to 5 pm on the second day. This will allow all cat owners to have a chance to get their cat(s) vaccinated during the times they are available.

      After about three weeks, each owner should have vaccinated their cat(s). If not, then there will be a fine of $100 per cat per week that they are not vaccinated. This is for the safety of the public and to make sure that people don’t put off getting their cats vaccinated. During this three week mark, veterinarians in the affected areas will send us their patient list of people who did not come in for their appointments. These are the people that will get fined unless they have the documentation that their cat was vaccinated.

      Animal control centers will use the cat traps to collect feral cats. While handling and moving the cats, protective equipment must be worn. These will have long sleeves and pants so that the fleas will not be able to reach bare skin (Nazarro 2010). To make sure enough feral cats are caught, a quota of 5 cats per week will be implemented until no more cats without owner are left to wander around. If the animal control centers do not fill this quota, then their government funding will be lowered.

Insecticide:

      Local animal control will be made to survey and report areas that are at high risk of flea infestation. As soon as these areas are identified, they will be contained, sprayed, and monitored until determined to be safe. If these areas are found in residential areas, then the neighborhood will be informed to stay away until the infestation has been controlled and the insecticide dried. Each home with a cat that tests positive for UEBOV will be sprayed and monitored until the infestation is controlled. If the residents do not allow appropriate control measures, local law enforcement will be employed to force compliance. In high risk residential areas, it will be highly recommended that all bedding, carpet, and anywhere fleas could make a home, be replaced. People applying insecticide and people at risk of insecticide exposure will be required to wear masks and protective gear.

Expected Outcomes

      With both the Felis reservoir vaccine and the insecticide combined with an IGR to reduce the population of C.felis, we have figured out a way to break every portion of the vector transmission cycle. If all the procedures pertaining to vaccination, isolation, and insecticide control are followed, then full control should be reached in about a year to two years.

      The Felis vaccine will help reduce the number of domesticated cats infected with the pathogen, reducing the population of infected vectors that can then infect humans with UEBOV. All infected cats that are quarantined may be at higher risk being around other infected cats, but will either become immune to the disease or succumb. Either way, the reduction of infected reservoirs out in the general public reduces the risk of humans becoming infected as well.

      The vaccine alone will not reduce the chances of United States ebolavirus from spreading, insecticides are also needed to reduce the outdoor population of the vector, C. felis. Insecticides will reduce the indoor populations of the vector greatly as well, reducing the probability of cat owners from getting infected.  With the insecticide kits, we are looking to see a real high reduction in flea populations around infested areas such as neighborhood parks and yards. All regions in the infected towns will be examined, assessed, and highly infested regions will be treated. This treatment, if all instructions are properly followed especially the multiple insecticide applications, will quickly reduce neighborhood populations of the vector. This method may reduce other pest populations, but overall decreasing the number of our vector contaminated with the pathogen is more important than not harming the other pest populations at this time.

      The greatest problem we may have with our final control plan is the public’s opinion of vaccinations and insecticides. With the growing number of people who think vaccines do more harm than good, there may be some backlash in forcing everyone to get their cats vaccinated. Hopefully, the $100 fine will prevent those cat owners from skipping out on the vaccine though. Also, the vaccine will only be given by licensed veterinarians so that it will be properly administered and will not hurt the cat in the process. For those owner worry about after effects, veterinarians may schedule a consultation a week later to check up on any symptoms that a cat may have that the owner thinks is from the vaccine. Isolation of infected cats may upset the owner as well, but we will insure the owner that the cat will have a higher chance of survival if treated with constant care.

      The residents of the infected areas may also be antagonistic toward the insecticides since they will worry about how pesticides will affect the environment. The sprays do not affect animals though, but we will keep any animal, including humans, away from the spray site until 30 minutes after spraying is completed. Another issue that may come up with insecticides is resistance of C. felis to the chemicals used. This will be prevented by following through with the treatment until all the cat fleas are killed. Subsequent sprays may be needed for this and may take many months. If the sprays stop working, then another chemical will be researched in the future, and replace our current ones, Permethrin Pro and Precor.

For the future, vaccination against UEBOV will become a regular operation of veterinary visits. This will continue for at least 5 years, but once your cat is vaccinated, it will never have to be vaccinated for UEBOV ever again. After 5 years, it may not be mandatory for cats to get vaccinated. The pathogen may have been eliminated from the environment and the vaccine may not be required. Isolation of cats will reduce over time as more cats get vaccinated at an earlier age and won’t have to worry about getting UEBOV. After 2 years, insecticide use will also return to only using it when your house is filled with fleas. By this point, infected fleas should be dead and newly hatched fleas won’t be infected.

      In the case of relapses, a hospital should send us information of anyone that dies from United States virus. This will help us catch the spread of the disease early and we may just be able to quarantine the house and pet of the affected person. Then the house and lawn can be sprayed with insecticides and cats in the nearby area can be vaccinated, if not already. The cat that was quarantined will be monitored for the disease and if after a week shows no signs or symptoms, it will be vaccinated and released to a relative of the patient. However, if there are multiple cases of United States virus in one town, then the procedures stated in this control plan will be implemented in that town to decrease and stop the spread.

      In all, our final control method may reduce other reservoir and pest populations and our vaccines/insecticide kits may cost us and invoke the general public, but the risk of our disease spreading is more costly and deadly. It is extremely important for us to break every possible portion of our transmission cycle and we believe this is the best way to do so.

References

Aberdein, D., J.S. Munday, C.B. Dyer, C.G. Knight, A.F. French, and I.R. Gibson. 2007. Comparison of the histology and immunohistochemistry of vaccination-site and non-vaccination-site sarcomas from cats in New Zealand, New Zealand Veterinary Journal, 55(5):203-207.

Marzi, A., T. Reinheckel, and H. Feldmann. 2012. Cathepsin B & L Are Not Required for Ebola Virus Replication. PLoS Negl Trop Dis. 6(12): 1-10.

Nazarro, L. 2010. Flea bites: diagnosis, treatment and prevention. BJHA. 4(9): 442-444.

Professional Pest Control Products. 2016. Flea Control Indoors, Killing Fleas, Permethrin, IGR, Precor. http://www.pestproducts.com/fleacontrol.htm

Spengler, J.R., S. Stonecipher, C. McManus, and H. Hughes-Garza. 2015. Management of a pet dog after exposure to a human patient with Ebola virus disease. J Am Vet Med Assoc. 247(5):531-538.

Tafuri, S.,M.S. Gallone, M.G. Cappelli, D. Martinelli, R. Prato, and C. Germinario. 2014. Addressing the anti-vaccination movement and the role of HCWs. Vaccine 32(38):4860-4865