METHODS FOR DISINFECTION OF NONCONVENTIONAL AREAS AND SUBSTANCES WITH VIRULICIDE SUBSTANCES

INFORMAŢII GENERALE The major risk of FMD contamination is represented by the infected animals and their products. Secondary, there are the persons having contact with the disease, with contaminated materials or with vehicles used for transportation of these animals, products, materials. In order to control a FMD outbreak it is very important to minimize the risk of virus dissemination from a farm to another farm.

The classic method of virus dissemination is represented by the movement of the infected animals and their products and also by the movement of humans, vehicles and materials contaminated with the virus. At local level, the virus is spread in places where the animals come in contact each other such as watering places or milking platforms. Thus, applying an adequate quarantine and a proper disinfection, the dissemination of the disease can be reduced or eliminated. The virus can be found on the person’s clothes and skin and also in the air expired during breathing, coughing, speaking, sneezing etc. Thus, a person coming from an area suspected to be infected with FMD virus have to make sure of removing the live virus (showers, hair washing and clothes, shoes disinfection)

Air dissemination is an important issue because it allows the virus to pass long distances in favorable conditions and that cannot be controlled. Taking into account that certain studies showed the risk of carrying the virus in the nose and throat, it is recommended for persons having contact with infected animals to avoid contact with susceptible animals for at least the following 3- 5 days.

INFECTED ANIMALS PRODUCTS FROM INFECTED ANIMALS PERSONS (HAIR,CLOTHES, NOSE, THROAT) VEHICLES BUILDINGS MATERIALS FOOT AND MOUTH DISEASE

! If a farmer or the farm veterinarian suspects FMD in the establishment, he has to apply immediately the proper quarantine measures, without waiting an official confirmation.

! All the persons that leave an area in which susceptible animals exist, must wash and disinfect themselves as if the area was infected. All the persons entering a space with susceptible animals have to wash and disinfect themselves as if they were carrying the virus on shoes, even he was not in contact with the animals – by example public roads which could be contaminated.

Disinfection of the buildings and annexes The buildings and the neighborhood annexes have to be cleaned using a pressure flexible tube and after that using an approved disinfectant. The disinfection of the buildings, other annexes and equipments is performed in 3 steps:  The primary disinfection, directly applied after the virus source was removed by cleaning  Cleaning and general disinfection  Final disinfection before repopulation.

General disinfection principles and procedures The disinfectants which will be used and their concentrations have to be officially recognized by the National Sanitary Veterinary and Food Safety Authority as disinfectants which guarantee the destruction of the FMD virus. The activity of disinfectants should not be decreased by long storage times The disinfectants and procedures have to be chosen taking into account the nature of the areas, vehicles and objects which have to be treated

! It is very important to use efficient disinfectants substances A LOT OF COMMON DISINFECTANTS ARE NOT EFFICIENT AGAINST THE FMD VIRUS. The efficient disinfectants are the acid and alkaline ones. Adding small quantities of detergent can increase the efficiency. The details regarding added quantities have to be verified for each disinfectant. Some disinfectants are recommended for different surfaces, by example citric acid 0.2% for the milking equipment and sodium carbonate 4% for animal folds.

The disinfectants are used in order to destroy the infecting organisms. They represent a high risk for other organisms, it involves a potential risk of environment pollution, especially as regards the wild fauna. Any used disinfectant has to be efficient and also to have a minimum impact on the environment and public health, according the most performant available technology.

The conditions for using degreasing agents and disinfectants have to assure their efficiency. The technical parameters have to be respected (the requested pression, minimum temperature and contact period ) The activity of the disinfectant should not be compromised by the interaction with other substances, such as degreasing agents. IT IS ESSENTIAL NOT TO MIX DIFFERENT TYPES OF DISINFECTANT. MOST OF THE DISINFECTANTS ACTS BY INCREASING OR DECREASING THE Ph, making the area acid or alkaline Mixing an acid substance with an alkaline substance a neutral pH will result – which is not efficient for FMD virus inactivation.

The following general rules will be applied: Complete soaking with disinfectant of the bedding, garbage and excrements with disinfectant; Washing and cleaning by brushing of all the potential contaminated surfaces, especially soil, floors, platforms and walls after removing or disassembling the equipments Further application of the disinfectant for a minimum contact period, as stipulated in producers recommendations; The water used for cleaning operations will be removed as to avoid any risk of virus spreading and according the official veterinarian instructions.

When cleaning is performed with under steam liquids and after disinfection, the recontamination have to be avoided; The operations of cleaning and disinfection have to be written down in the exploitation register or, for vehicles, in their register. When the official authorization is necessary, they will be certificated by the official veterinarian responsible for surveillance.

The feet disinfectant, sprays etc will not be effective if: People are not using them (by example they are afraid they will deteriorate the shoes) The thick contamination (manure, soil, mud) is not removed beforehand – the organic material is preventing the efficient action of the disinfectant The used disinfectant is not adequate The disinfectant is not kept in proper concentrations – by example it is diluted after raining, lost in leaks etc Incompatible disinfectants are mixed together (by example mixing acid disinfectants with alkaline disinfectants)

Specific provisions regarding cleaning and disinfection of infected exploitations 1.Primary cleaning and disinfection During animal slaughtering all the necessary measures have to be taken in order to avoid or to minimize the spreading of FMD virus. This includes, among other things, the installing of temporary disinfection equipment, supplying with protection equipment, showers, the decontamination of the used equipment, tools and facilities and interruption of the electric energy supplying the ventilation systems. The carcasses of killed animals have to be sprayed with disinfectant and removed from the exploitation in covered and tight containers, for processing and neutralizing.

As soon as the carcasses were removed, in order to process and neutralize them, the parts from the exploitation where the respective animals were accommodated and any other part of other buildings, yards etc which were contaminated during killing, slaughtering or postmortem examination will be sprayed with authorized disinfectants. Any tissue or the blood which could flew during slaughtering or postmortem examination and any significant contamination of buildings, yards, tools etc have to be removed and neutralized together with the carcasses. ! The used disinfectant have to remain on the surface at least 24 hours.

2. Final cleaning and disinfection Grease and dirt have to be removed from all the surfaces by applying a degreasing agent and washing with cold water After washing, a disinfectant will be sprayed. After seven days, the buildings will be treated again with a degreasing agent, washed with cold water, sprayed with disinfectant and washed again with cold water.

VEHICLES DISINFECTION ! Any vehicles leaving an animal exploitation should be cleaned and disinfected as if the area was infected. ! Any vehicles entering into an exploitation with susceptible animals have to be cleaned and disinfected as if they were carrying the virus before entering the exploitation, even he was not in contact with the animals – by example public roads which could be contaminated.

The disinfection of bedding and manure The solid phase of the manure and the used bedding have to be stacked for warming, better by adding 100 kg granulated calcium oxide to 1 cubic meter of manure, sprayed with disinfectant and left for at least 42 hours in a covered heap. The liquid phase will be stored for at least 42 hours after the last add of infecting material. This period can be extended in case of severe contamination or in case of unfavorable climatic conditions. The period can be shortened if a disinfectant was added as to modify the pH.

Special cases When, due to technical or security reasons, the procedures can not be followed the buildings will be cleaned and disinfected as much as possible in order to avoid the FMD virus spreading and will be not populated for at least 1 year. In case of open air exploitations, the NSVFSA can establish specific procedures for cleaning and disinfection taking into account the exploitation type and the climatic conditions. The NSVFSA can establish specific procedures for the disinfection of manure accordin scientific data which will prove that the method is efficient.

The necessary period of time for quarantine and disinfection before repopulation The period of time which is necessary for an infected farm to be repopulated depends on the in force recommendations from each country. The recommended period of time before repopulation: “At least 21 days after the final disinfection of the area “; 28 days after the final disinfection or 42 hours after the slaughtering; 6 weeks after the slaughtering or at least 4 weeks after the final disinfection if the infection is very aggressive

“In all the areas where animals are slaughtered due to this disease, the cleaning and disinfection have to take place before the repopulation with other animals Cleaning and disinfection usually means cleaning the area and the equipment but it is also possible that the farm remains under restrictions for a longer period (12 months) in order to allow the natural destruction of the virus.

The restrictions remain available until: The establishment was repopulated and the animals are not showing any sign of disease. The repopulation can take place only after a minimum length of time after the final disinfection(stated by the official veterinarian). or A longer period of time passed so the restrictions can be cancelled and it is possible to repopulate without authorizations, inspections or samplings.

NSVFSA President Order No. 113 from 27 April for the approval of the sanitary veterinary norm regarding measures for foot and mouth disease control ; - transposes into the national legislation the Council Directive no. 2003/85/CE regarding the community measures for the FMD control stipulates that: The National Sanitary Veterinary and Food Safety Authority have to be sure that the operations of cleaning and disinfection are performed under an official supervision and according the official veterinarian instructions, using disinfectants and concentrations of these disinfectants approved and registered by the competent authority responsible for putting on the market of biocidal substances, according Government Decision 956/2005