PRACTICAL FIELD SIMULATION EXERCISE - BASIC
TRAINING FORM OF THE PREPAREDNESS AGAINST FOOT
AND MOUTH DISEASE
V. Kouba
Formerly: Chief, Animal Health Service, Food and
Agriculture Organization of the United Nations; Czechoslovak and Czech Chief
Epizootiologist; Professor Epizootiology,
1. Introduction
a) The key problem of successful control
of foot-and-mouth disease (FMD) is to detect
in time primary outbreak as well as the secondary ones together with immediate isolation of well identified
suspect area! This depends on the competence of all who are involved in FMD-susceptible
animal species breeding, production and trade, i.e. who are in the “first anti-FMD
front line“. All of them should be properly informed and instructed. The decisive
role have the veterinarians who are able to recognize the suspect cases, to apply immediate
provisional isolation measures avoiding further spread and to inform without
any delay relevant veterinary and government authorities realizing follow-up
actions. The task is not to repeat the past errors in detecting and controlling
the FMD. There are different forms of the veterinary staff preparedness against
FMD. One of them is represented by simulation exercises organized by local, national
authorities and international organizations.
b) Relatively easy and cheap-to-prepare theoretical and paper “simulation exercises” as well as simple demonstrations
to passive watching and listening participants have
low effectiveness and the acquired information can
be easy forgotten.
Better to call them as “information/demonstration simulation” or “opinion/experience
exchange workshops” or “simulation seminars” preparing administrative (“armchair”)
anti-FMD solutions. In these cases there is not need to work with animals or
even to see them. This form is to some extent also useful but not real effective preparedness for
practical activities starting always at the field level. It reminds the
theoretical exercises of generals without practical field exercises of the
decisive factors in any war – well trained solders !
Examples: The above theoretical
“simulation exercises” have been organized by the European Union, European
Commission for the Control of Foot-and-Mouth Disease (EUFMD), etc. The latest
one took place in Tervuren,
Note: Similar theoretical effect can
have simple distribution of special instructive videos, DVDs and films or
distributing information materials such as instructive brochures containing the
anti-FMD instructions, models of emergency plans, specific forms and
questionnaires, legislation documents, specific publications, examples of
actions, pictures of the FMD and of similar diseases, etc. for individual
studying. The available literature sources on the FMD are the richest of all
animal infections !
c) Theoretical “simulation exercises”
including only limited number of participants can be replaced by modern and
more effective electronic simulation
exercises, preparedness trainings or workshops using on-line internet
communications. The use of electronic tools can provide information and
instructions as well as the chance of discussion through the internet when exploiting
the best international FMD specialists and the most suitable audio-video
instructive material. This kind of electronic exercise has multiplying effect due to great number of participants.
Example: One of the first
electronic workshops was organized by the FAO in 2000 (from 18 September to 27
October) dedicated to land and water problems: “Key questions addressed in the workshop were outlined in an introductory
note. Supporting documents included two discussion papers, five background
papers and 31 case studies. There were 471 participants (!), 38 of whom made
contributions, comments and suggestions for future activities. The
interventions were summarized on four occasions as the workshop proceeded. A
full documentation of the workshop material was included in a CD”.
d) The preparedness against the extremely
dangerous and rapidly spreading disease such as the FMD cannot be based on paper work and bureaucratic formalism
or on using non-sense software modelling
the extremely complex and dynamic biological process under particular
conditions being in all cases different.
Example: The application of
very specific theoretic software called EPIMAN-FMD “for FMD control” developed
in New Zealand and bought also in the European Union contributed to
catastrophic outcome of the United Kingdom 2001 FMD panzootics (e.g. daily
sending from
e) The above mentioned theoretical “simulation exercises” strongly underestimate
the fact that any effective anti-FMD measures must be based on f i e l d clinical and epizootiological investigations
to reach reliable diagnosis confirmed virologically. Without very good knowledge of
the local and territorial FMD situation the anti-FMD measures can be applied only by “blind” or “semi-blind”
decision-makers “shooting at random”. The results of the field investigations
start the anti-FMD measures exploiting in-advance-prepared emergency plans, legislation
and instructions as well as other relevant components (used also in the
theoretical “simulation exercises”). The
field investigation represents the first and decisive step of any effective
anti-FMD actions while the measures
represent the follow-up second step !
There is not any doubt that also theoretical
“FMD simulation exercise” of anti-FMD has its importance, however, if not
combined with field investigation training it conduces to very dangerous distraction
from the main problem of anti-FMD preparedness. Unfortunately, the theoretical
“paper exercise” of managerial/administrative procedures, isolated from field
investigations’ training, creates general false impression of anti-FMD
“preparedness”.
f) We have to consider very bad experience gained in the recent FMD panzootics. The
catastrophic consequences were caused mainly due to absolute absence of practical preparedness of veterinary
manpower. Almost all
veterinary faculties and postgraduate trainings in the world are
preparing the veterinarians mainly for small animal practice – pet animal medicine and food-producing large animal
practice is strongly underestimated. The teaching in anti-infection
preparedness is too theoretical giving minimum or zero attention to practical
skills. Private veterinarians having rich experience of small animals as well
public service veterinarians accustomed to work in offices (mainly with the
computers) were often not able to investigate clinically the animals of FMD susceptible species due to lacking necessary skills or due to having
fear of hard work with large animals or being not willing to work under very
difficult and often unhygienic environmental conditions. The majority of these
veterinarians were not prepared (unable) to investigate properly all FMD-predilection
body areas such as mouth cavity and tongue as well interdigital spaces. Many
veterinarians were even not able to catch and fix the animals, mainly when these
were not stalled fastened or having free movement on pastures. A lot of the
veterinarians were even not able to open
the mouth and to pull out the tongue (basic clinical method for FMD
investigation !) not only in cattle but also in sheep, goats and pigs, not
mentioning the difficult investigation of their young categories.
g) Clinical investigation of suspected and threatened
herds represents very hard work,
mainly when lacking necessary supporting staff. Therefore, the FMD was frequently not detected in time or ignored
or misdiagnosed. The veterinarians were very often not able to correctly identify
the focal and perifocal limits and to apply adequate anti-FMD measures due to
investigating only very limited number of animals. Due to investigating minimal
number of animals there were established incorrect limits of the outbreak and
perifocal zones and applied incorrect anti-FMD measures. These zones were
usually identified by guesswork either too small or too large. Scientific and
the most effective anti-FMD measures can be apllied only when systematically
and properly investigating all diseased, suspect and threatened animals. The FMD
diagnosis of animals specifically diseased, suspect and
threatened cannot be
identified from distance. Anti-FMD
actions cannot be successful without hard professional work at grass-root level
from the very beginning up to the end of the FMD epizootics.
Example: The worse recent experience has been gained
in
h) The majority
of the veterinarians involved in the anti-FMD campaigns were not able to
identify the form of the disease, stage of the epizootics, age of pathologic
changes (to identify the eldest specific changes, i.e. to can estimate the moment of FMD virus introduction
and thus to identify possible source and introduction way and the destination
of eventual disease further spreading) and to select the best possible specimen to be collected and sent to laboratory. *)
i)
Important indicator of the preparedness to discover in time primary outbreaks
of the FMD is the ratio
primary/secondary outbreaks: Taiwan in 1977 = 1 : 6,147, UK in 1967/68 = 1 : 2,364; UK in 2001 = 1 : 2,030, Greece in 1994 = 1 : 94,
Netherlands in 2001 = 1 : 26; European
Union in 1977-1987 average = 1 : 54;
Europe in 1991-2000 average = 1 :
10,5. (OIE, FAO, DAVIES). These examples document very late discovery and
blockade of the primary outbreaks due to
weak or not existing effective anti-epizootic surveillance at field
level and due to lack of necessary
number of well trained veterinary professionals.
j)
Above mentioned examples show enormous difficulties to detect in time
introduced diseases in spite of the fact that the FMD belongs among diseases
with clinical manifestation more expressed than in the majority of important
communicable animal diseases. There are not two identical cases, i.e. every
case is different ! The FMD has different forms: from sudden death,
peracute, acute, subacute, chronic and
subchronic course up to asymptomatic “virus carrier”.
k) The majority of the veterinarians involved in the anti-FMD campaigns were not able to carry out necessary epizootiological
investigations to answer the basic questions: what,
where, when, why, how, how many ? They were not able to determine: diseased, epizootiologically
suspect (contacts), directly threatened
and indirectly threatened (each of these epizootiological characteristics
requires different diagnostic approach and control measures such as intrafocal
isolation and selection for immediate slaughter-destruction animals. They were
not able to determine the limits of
affected place (outbreak) as well as of perifocal zone and to dictate
provisional outbreak isolation measures as well as intrafocal and perifocal
provisional emergency measures.
l) Considering
the FMD epizootiological situation, intensive long-distance international trade
in animals and animal products as well as very bad experience in controlling
this extremely dangerous animal disease, it can be stated that the world veterinary staff is not adequately
prepared for the FMD emergency ! No any international organization and
no any veterinary faculty is organizing particular anti-FMD training programmes
through intensive practical field simulation exercises based on clinical and
epizootiological investigations of animals. Theoretical/paper
preparedness in case of the FMD = no
preparedness !
More information
see in http://vaclavkouba.byl.cz/emergency.htm.
---------------------
*) Note: Often in real cases many animals must be
examined before sufficient quantity of adequate material suitable for
laboratory investigation is collected.
k) The most effective
anti-FMD preparation of veterinary manpower is practical field simulation exercise
applying the principle “learning by doing”, i.e. training the skills difficult
to forget. ¨
Even the Old Romans knew that “Usus magister est optimus” (“Practice makes perfect”).
l) This paper is based on
available international simulation exercises’ reports and on author’s national
and international experience with FMD control and eradication as responsible
epizootiologist and with practical field FMD-simulation exercises as their instructor.
2. Objectives
The main objectives of FMD simulation
practical field exercise consist in achievement that the participants under emergency situation:
a) will know how
and be able to carry out clinical diagnosis after investigating all FMD-
predilection body areas of susceptible
species animals of different categories (incl. young animals);
b) will know how
and be able to carry out epizootiological diagnosis, after considering
anamnesis information, results of clinical investigations and investigating
local situation, i.e. to identify affected, suspect, contact and threatened
animals and their areas/premises, limits of potential outbreak, intrafocal
structure and perifocal zone as well as to predict the likely spread;
c) will know how
and be able to identify FMD-free animals, herds and areas;
d) will know how
and be able to identify and dictate provisional measures to isolate the suspect outbreak and perifocal zone;
e) will know how
and be able to find out animal(s) with the best FMD-suspect pathologic changes
for sample collection and to pack the suspect tissues and liquids in proper way
for sending them to diagnostic laboratory (with respective accompanying
documents);
f) will know how
and be able to find out animal(s) with the eldest FMD-suspect pathologic changes
to can estimate the date of FMD virus introduction and the disease duration
(critical period of possible spread outside of suspect area);
g) will know how
and be able to trace the origin and introduction way of the FMD as well as
eventual spread from the given outbreak (considering movement/transfer of
animals, products, equipment and material, movement of persons including vet.
practitioners, etc.);
h) will know how
and be able to elaborate simple maps (schemes) of the suspect outbreak and perifocal
area limits and their epizootiological structure;
i) will know how
and be able to carry out biological test on the spot for provisional
differentiation of eventual FMD and other vesicular diseases;
j) will know how
and be able to identify specific intrafocal initial sanitation (disinfection) measures.
3. Participants
a) The participants
(trainees) should be of similar managerial, technical and experience levels.
The group should represent a relatively homogenous unit which facilitates the
work of the teachers. However, the practical field training is similar for all
types of participants who should finish the exercise with necessary practical skill
to investigate suspect animals and to identify
local epizootiological situation.
b) Due to the fact that any veterinarian,
namely working in field practice and slaughterhouses, can be the first in
contact with primary FMD outbreak as well as the secondary ones, there is an
urgent need that all of them to be properly trained under simulated emergency
conditions. They represent the “first front line defence”. A l l veterinarians, i.e. not only of
public services but also private veterinarians (not only accredited ones) being
in contact with FMD susceptible species animals, should pass this postgraduate
practical training programme. Veterinary faculties should include this kind of
field practical simulation exercise as a normal component of undergraduate
programme for last year students. Also veterinarians – university teachers of
veterinary faculties should be trained to be prepared for their eventual involvement
in anti-FMD emergency actions in the country.
c) Among the first participants should be leading officers of public veterinary
service beginning with Chief Veterinary Officer. They should know how and
be able to investigate FMD-suspect animals/herds, to reject
or confirm FMD suspicion and to carry out local epizootiological diagnosis. They should know how
difficult is to investigate thoroughly the suspect (diseased) herds, outbreak
and perifocal areas and what is required for this kind of activity. This
knowledge is extremely useful for effective management in case of real FMD
control actions at territory or country levels.
d) Number of participants depends on local
conditions. The most important is the requirement that the teacher should be
able to manage properly the exercise dedicating maximum of time to the
participants when investigating animals, herds and surrounding area. His role
is namely initial demonstration following by supervision of the participant
work and providing necessary consultations.
Example: In my practical
FMD simulation field exercises the participants were usually subdivided in four
small groups with 4-5 participants. In each group one trainee was selected to
be responsible for his group activities, i.e. for assuring the implementation
of the particular programme as scheduled. Usually, one participant was
investigating and other one was writing down the findings (results) in a simple
protocol for follow-up evaluation. Then the role of individual participants and
the groups was changed (rotated) in
order that everybody passed all components
of the training.
4. Teachers
a) Successful
practical field simulation exercise requires the teachers (trainers or
instructors) to be the best possible international specialists for
international simulation training and the best possible national specialists
for national simulation training, i.e. fully competent in clinical
investigation of FMD-susceptible species animals and in field epizootiological
investigation of particular diseases. The priority to be given to those having personal practical experience of the
FMD and with the management of simulation exercises in the field.
Unfortunately, they are not always available (they are not many).
b) International field simulation training
should be organized by relevant international organizations for the future
national teachers to be well prepared for national practical field simulation
exercises. The instructors of these courses to be the best in the world
having practical experience with FMD field diagnosis and control. The
multiplying effect consists in applying the principle “teaching teachers to teach”.
c) Similarly, at national level should be
trained first future teachers to transfer the knowledge and experience to the
others using local language considering local conditions.
d) It is
recommendable the teacher to be assisted by somebody (at least by one
assistant) being responsible for the exercise organization, management and
solution of non-professional problems. The teacher should have all necessary conditions to can
concentrate his effort on professional programme only.
5. Place and duration
a) The selection
of suitable place depends on local availability of FMD-susceptible species animals
such as cattle, pigs, sheep or goats and on the agreement with the animal
owners and local authorities.
b) For practical
FMD field simulation exercise it can be selected any place in livestock
husbandry, slaughterhouses or villages according to local conditions The most
suitable location is a major farm (herd) or ranch belonging to universities or
other education institutions where the animals are kept for teaching purposes.
From economic point of view it is usually cheaper to use farms or ranches
belonging to state, local government or agriculture cooperatives than to
private profit-oriented owner.
c) The animal
owners and local authorities in simulated outbreak area and perifocal zone must
be informed in advance and agree with this kind of training, i.e. to permit the
entrance and investigative work to be carried out by the participants. The
animal owner should agree with answering anamnesis questions. The answers should
be as much as possible real or simulated (following previous instruction of the
teacher).
d) The duration
of the exercise depends on the particular programme considering the time needed
for all participants to pass all component of the training.
Example: In my practical field simulation exercises
the minimum duration was 3 days. One day was dedicated to detailed information on
FMD and similar diseases and to exercise
introduction, one or more days to the proper individual field work
(investigations and measures) and one day to exercise evaluation.
6. Organizational preparation
a) The practical
field simulation exercise must be well prepared also materially, i.e. to be
available in sufficient quantity: protective clothing, boots, gloves, equipment
for animal fixation (lassos, nose leads, hog holders, etc. ), mouth openers, short
wooden sticks, specula for mouth
investigations, cloth/towels (for fixing the tongue), flashlights with batteries, veterinary
thermometers, large and small
oesophageal-pharyngeal sample collectors (probang cups), equipment (kit)
for specimen collection, packing and transport
(surgical scissors, vials, syringes,
needles, etc.), brushes for cleaning
interdigital cleft of the feet, equipments for cleaning and disinfection
(including disinfectants), buckets, communication equipment, instruments for
eventual local slaughter, maps
(local and territorial), anamnesis questionnaire, forms for findings’
annotation (clinical and epizootiological investigation protocols) and for
reporting; writing tools; first aid kit,
paper towels, etc.
Note: Using video camera documenting the exercise for its evaluation
has proved to be very helpful.
b) The equipment
for the restraint of animals, such as races, crushes, pens etc. are necessary
to facilitate clinical investigation and collection of sample material.
c) Also in the cases when not all above mentioned
materials are available, the practical field FMD-simulation exercise should be performed. Under
real emergency it cannot be expected ideal conditions and availability of all
above mentioned tools for the investigations. Therefore the participants should
be trained for extraordinary situation using improvised simple tools and
methods.
d) Very
important is the selection of the
animals for the exercise. The teacher should visit in advance the place and
the herds selecting animal groups of different FMD-susceptible species and
their different categories suitable for the exercise. Priority attention should
be given to sick animals, animals prepared for culling and animals of lowest
value for the owner. It is recommendable the teacher to find out himself the
animals with pathologic changes (if any) on FMD-predilection body areas what
can be used for FMD differential diagnosis explanation. The participants, without
being informed in advance, should try to find these animals themselves
investigating all the herd.
e) It is
advantageous to have some animals with clinical symptoms similar (naturally or
artificially) to vesicular diseases.
Note: Exceptionally, in
agreement with animals’ owner, I used chemically provoked artificial changes
similar to FMD lesions in some selected animals (e.g. non healthy animals of
low value destined for premature culling) in a major herd. The participants
were not informed and they must search
for them using clinical investigations and find them. The findings served also
for differential diagnosis analysis. The lesions similar to FMD were provoked through the
inoculation of pure turpentine essence
(intradermic about 0.05, maximum 0.1 ml) in the tongue, lips, etc. The changes
resembling the vesicles development
disappeared under normal conditions during about one week.
f) The
interference in current local animal operation and production must be avoided
as much as possible. Clinical investigations must be performed very carefully,
i.e. without injuring the animals.
g) It is obvious
that organizational preparations include also participants’ accommodation, catering
and transport.
7) General introduction
a) The exercise
should be introduced by detailed information and discussions on FMD situation
in the world, region and country, on FMD
introduction risk, on FMD characteristics, detailed clinical investigation and
diagnostic procedures, on detailed epizootiological investigation and diagnostic procedures, on differential
diagnosis comparing FMD with other diseases, on pathologic changes which could be
confused with FMD, etc. The use of colour slides, films, videos, etc. is obvious. The use of disease
recognition multimedia software is welcome. The attention to be given also to
the intrafocal and perifocal measures and to anti-FMD preparedness.
b) All
participants should be provided by
relevant documents, instructions, brochures (manuals with colour
pictures) with detailed description of the FMD and similar diseases, etc. as
well as by the forms for anamnesis data recording and by the protocols for clinical and epizootiological
investigations.
8) Field exercise introduction
a) Initially the
participants should be acquainted with the exercise objectives, methods,
location, organization, management, tasks of individual participants and
groups, working conditions, forms of evaluation and final examination.
b) The exercise
should start with dramatization of
hypothetic situation of the suspect occurrence of the FMD to sensitize the
participants. The teacher should describe fabricated alarming history of
FMD suspicion providing as much as possible details important for the exercise.
There are not any limits for the teacher fantasy when respecting logic, disease
epizootiology and local conditions. Simulation
should be as real as possible.
c) The teacher
should describe in details simulated situation (suspicion of FMD outbreak)
using simulated information of the animal owner on: the disease occurrence, frequency,
losses and duration; size and structure of local animal populations; animal
health situation inside of the farm and in the neighbourhood; provisional
measures applied, etc.
d) The teacher
should explain in details the field activities under simulated conditions, describe in details all exercise objectives
(as mentioned above) and the methodology for their reaching. Particular
attention to be given to clinical investigation/diagnosis of individual
FMD-susceptible animal species and categories, to detailed procedure of
epizootiological investigations, to the selection of the most suitable samples and
to the methods of packing for sending them to the laboratory. The participants
should be instructed also on field biological tests.
e) The teacher should identify places and timing
for total and partial activities, explain rotation system of the groups and provide
a map or scheme of the area indicating places and time of particular field
practical activities (use of notice board).
f) The teacher
should inform on the most frequent errors and deficiencies when implementing
individual objectives of the exercise.
g) It is
recommendable that the participants obtain a list of their tasks, to avoid
misunderstandings during the training, and eventually some data on the place,
timing and organization of the field exercise.
h) The
participants should be instructed how to identify investigated animals, how to
note the findings and how to formulate the recommendations for the measures to
be applied (for follow-up analysis and evaluation).
i) In other
words, the participants should be properly instructed in time to can start
practical field exercise without any delay due to a gap in initial instructions
(not to waste time allocated for practical field work).
9) Starting practical field simulation exercise
a) Task declaring:
Reject or confirm FMD suspicion, identify the
limits of simulated outbreak and perifocal zone and apply provisional anti-FMD
measures in and around simulated outbreak area.
b) First step of
the exercise on the spot should be immediate simulated isolation of the farm or
other place (to be provisionally visibly marked, e.g. by warning placard) with
simulated suspect animals following by immediate simulated reporting to
relevant local veterinary authorities and by immediate thorough investigation
of the suspect animals (without wasting time with paper work that drags away
from the key activity).
c) The
participants should be divided in smaller groups and indicated on starting time
for particular investigations and rotation of the groups. Considering local
conditions the grouping and exercise group location and timing should be
flexible as much as possible to facilitate to fulfil the exercise tasks. The
exercise organization depends on local conditions, number of participants and
groups, availability of suitable animals, time and space conditions, supporting
staff, communication facilities, etc.
d) Applying the
principle of “learning by doing”
requires that every participant should clinically investigate (thoroughly all FMD-predilection
areas of the body) several animals of all available FMD-susceptible species and
their categories and based on epizootiological investigations identify the
limits of simulated outbreak and perifocal area and suggest concrete measures
(to be later discussed with the teacher). The complicated conditions, faults and
difficulties serve also for participants’ learning.
10) Anamnesis:
The anamnesis provided by the owners proved
to be extremely useful for veterinary specialists investigating the case at the
very beginning, i.e. immediately after obtaining the report on the suspicion.
The participants should ask animal owner(s) or animal caretaker(s) or other
informed person(s) about simulated suspicion, diseased animals, previous and
current contacts of animals and persons
with outside places, previous introduction and transfer of animals to
other places, etc. The answers can be real or prepared in advance based on fabricated situation. The participants should
note anamnesis information.
Note: Under real emergency the anamnesis information
must be professionally verified..
Detailed anamnesis of selected 31 primary FMD
outbreaks are described in K o u b a (1961) publication (PhD thesis). These
texts based on real situations represent useful tool for starting FMD
simulation exercises, instead of artificial theoretical paper anamnesis.
11) Clinical
investigation
a) The clinical investigation is the key method
for implementing the tasks under the paragraphs 2a - 2f facilitating to
identify correctly all anti-FMD measures. The field practical diagnosis is
decisive for any anti-FMD control and eradication programmes, without regard to
management levels. Bad experience with theoretical approach isolated from the
reality causing enormous losses is a warning phenomenon! When replacing the
clinical investigation by only a demonstration for watching participants, the
simulation exercise is losing its sense and effect (= wasting time and money).
Everybody can study the FMD problems (books, legislation, instructions,
internet, etc.) at home, but practical training to get necessary grips cannot
be replace at all. Paper exercise is easier for the organizers but with minimal
or without practical effect in case of real FMD occurrence. The participants of
“paper simulation exercise” having fear
to properly investigate suspected animals were often giving the priority to
solve FMD epizootics in offices without seeing the animals and to use different
mathematical theoretical models. This “armchair approach” has caused enormous
losses during recent panzootics in
More information in http://vaclavkouba.byl.cz/biodisaster.htm
Practical problem solution of real FMD starts in
the field and ends in the field !
b) The clinical
investigations start with the animals indicated by the simulated anamnesis as
being suspect (diseased).
c) Simultaneously, the participants
should observe all susceptible animals on the premises by walking among the
animals in their normal habitat. Those lying down should be required to get up
and move, in order to observe any lameness or weakness. The animals should be
observed closely for lacrimation, salivation, nasal discharge, increased
respiration, shaking feet and other abnormalities. In dairy cows sudden
reduction of milk production must be also considered. Sometimes it is useful to
carry out a “feeding test” in order to observe any anorexia. Those animals
showing suspicious sign should be restrained and a careful physical examination
made before investigating the other ones.
d) Among
FMD-predilection body areas to be
investigated by all the participants are: mouth cavity (with and without
mouth opener and nose lead), i.e. tongue (dorsum up to its root, base and
lateral sides), upper and lower lips, gums, hard and soft palate, other oral
cavity surface, nostrils, surface of the nose (muzzle, snout of pigs), coronary
band, corium of dewclaws in pigs, interdigital spaces, teats and udder of cow,
sow, ewe and she-goat. Particularly difficult are the investigations of the
mouth cavity of young animals – calves, piglets, lambs and kids. FMD has
frequently been ignore or misdiagnosed in small ruminants. In some real FMD
cases in small ruminants the lesions are located only at the root of the tongue
as small vesicles or shallow erosions, i.e. not easy to discover them. The
measurement of animal temperature is obvious.
Caution should be exercised to prevent damage
to the mucosal membranes!
e) The
most important principle of the practical field simulation exercise is that
every participant thoroughly investigates
as much as possible animals of all FMD-susceptible species and their
basic categories !!! The participants should gain a skill of clinical investigation of
animals of FMD-susceptible species and of
timely discovery of vesicular disease suspect cases.
Note: In reality the
vesicles are not pathognomic for FMD alone, since they are also associated with
vesicular stomatitis, vesicular exanthema of swine and swine vesicular disease.
Classical vesicular lesions may not be found. When they occur they usually
rupture leaving eroded, haemorrhagic, granular mucosal surface of the mouth and nose, as well as the skin,
epithelial tissues of the feet and other regions. In swine, sheep and goat the
lesions on the tongue are usually small easy to be overlooked. In rare cases
lesions of the perineum, vulva or scrotum are seen. Tiger heart (grey, white,
or yellowish myocardial lesions) may be found in calves or in sudden death of
other categories. FMD has enormous number of clinical and epizootiological
forms from peracute deadly course to mild one up to sub-clinical infection and
carriers (e.g. in vaccinated animals).
f) Mass clinical investigations (e.g. of hundreds
of animals) are usually very laborious, mainly in the herds of free-ranging
animals. The difficulties are multiplied by insufficient staff for animal catching
and fixing, bad hygienic conditions, etc. The participants should be trained to
work also under these conditions to be able to replace missing supporting staff
when the emergency will require.
Note: The participants
should be trained to investigate the cattle mouth after pulling out the tongue
when fixing the head by nose lead and using mouth opener and also without them.
g) Similar demanding clinical investigation
is also key method for confirmation
that the animal is free of FMD changes what is very important for identification of perifocal and
threatened zone limits as well as for animal transfers, national and
international trade and slaughterhouse inspection. This methods is also used
when deciding about the application of the “stamping
out” to be sure that the slaughter of all intrafocal animals will represent
the end of the local FMD thanks to the confirmation of FMD-free status in
perifocal area and in threatened zone. Without clinical investigation
identifying correctly the perifocal limits very often the “stamping out” method didn’t block the FMD spread and the measures
becoming “semi-blind” or “blind”. Clinical investigation cannot be replaced by
any “paper/armchair” method.
Example: In October 2010 an
international team linked to the EU – TA
for Communication Campaign and Preparation Country Dossier for OIE Declaration
for FMD - presented to
The diagnosis
(confirmation) of specific health is often much more difficult than the
diagnosis (confirmation) of specific disease !
12) Differential
diagnosis
a) It should be taken into consideration
that every case of the FMD has different clinical and epizootiological picture
including atypical courses (e.g. FMD without typical vesicles) ! There are not two identical cases ! The
knowledge of differential diagnosis is of extreme importance.
b) Usually, when investigating herds with major number of animals, it can be found some
clinical signs such as excessive salivation, smacking of the lips,
traumatic lesions of the mouth, lameness, foot-rot, animal stamping its feet,
interdigital space erosion/excoriation, interdigital panaritium, lassitude,
pyrexia, anorexia, wounds, burns, abscesses, bovine papular stomatitis, mycotic
stomatitis, tongue actinomycosis, pseudovariola, mastitis, reduced lactation,
phototoxic dermatitis, pathologic changes caused by chemical irritants and by scalding,
etc., These changes can serve for FMD differential diagnosis to be explained by
the teacher and eventually for specimen collection.
c) Among internationally notifiable FMD
similar diseases belong: vesicular stomatitis, vesicular exanthema of swine,
swine vesicular disease, rinderpest, peste des petits ruminants, mucosal
disease, IBR/IPV, bovine malignant catarrh, contagious pustular dermatitis in
sheep and goats, bluetongue, sheep pox, goat pox, , etc.
d) Late discovery of the FMD caused its further spread and in some cases even by the
veterinarians themselves who continued in their work and visited other herds
not only in the same village. This is the worse what can happen to veterinary
service. Therefore, there is a need to be always very careful, i.e. always to
consider first the possibility of FMD suspicion and after rejecting it to
continue to finish the case diagnosis. There
is much more responsible and acceptable to make mistake in expressing the
suspicion of FMD existence, applying provisional isolation measures and
alarming the authorities, than vice versa !
The worse is to start with indecisive
speculation and theoretical “philosophy” letting the disease to spread instead
to apply immediate provisional isolation measures and thus providing necessary time
for diagnosis finalization.
Examples of real FMD cases
initially falsely diagnosed by field veterinarians as: rachitis, osteomalacia, rumen foreign body,
sudden change of feed, toxicosis by seed cakes, constipation, vesicular disease
of swine, pneumonia, suspicion of toxicosis, unknown infection disease,
postvaccination complications, alimentary intoxicosis, stomatitis mycotica, stomatitis
papulosa, bovine malignant catarrh, stachybotryotoxicosis alternans, mucosal
disease, panaritium, etc.
e) Sometimes, at
the end of the exercise, we slaughtered one diseased calf
not suitable for further breading and investigated also its internal organs
looking for pathologic changes in gastrointestinal places (mainly rumen pillars)
and myocardium.
f) In my exercises usually all work was done
by the participants themselves without the help of the farmers or workers who
under real emergency not always will be available in necessary number and of
relevant competence. The veterinarians themselves should be able to catch and
fix the animals. Fixing all animals of major herds and their clinical
investigations is physically very demanding work.
13. Epizootiological investigations
a)
Epizootiological investigation and diagnosis should answer the questions: what, where, when, why, how, how many?
b) Epizootiological
investigation on the spot supported by anamnesis information and clinical
investigations should determine
(identify):
- animals specifically diseased, clinically
suspect, epizootiologically suspect (contacts), directly threatened and indirectly threatened (each of these
epizootiological characteristics requires different diagnostic approach and
control measures);
- limits of affected place (outbreak) and of
perifocal zone;
- form of the
disease, stage of the epizootics, age of pathologic changes (to identify the eldest
specific changes, i.e. to can estimate the moment of FMD virus introduction and
thus to identify possible source and introduction way and the destination of
eventual disease further spreading);
- movement of
animals and their products inside of simulated suspect place and in the
simulated perifocal zone as well as
their movement to other places during last critical period;
- animals for intrafocal isolation, animal for
immediate slaughter (destruction, deactivation);
- the best
possible specimen to be collected and sent to laboratory *);
- provisional
outbreak isolation measures as well as intrafocal and perifocal provisional
emergency measures;
- employees
having FMD-susceptible animals at home (for further investigation and
observation);
- burial site and needs for local sanitation,
i.e. critical places, disinfectant types, concentration and quantity;
- prognosis of disease development;
- needs for further measures and provision of
staff, material, transport, logistic etc.;
- regime of systematic observation and further
investigations (surveillance), etc.
c) Perifocal epizootiological analysis is based upon anamnesis,
clinical investigation of FMD-susceptible animals and evaluation of disease
spread facilitating conditions in surrounding zone of simulated outbreak.
d) Results of local epizootiological
investigations represent the basis for any effective anti-FMD measures at all managerial
levels.
e) The
participants after finishing epizootiological investigations should recommend necessary intrafocal and
perifocal concrete measures in written form (including scheme) to fit to simulated
situation and local conditions. The recommendations to be presented for comments
and for final evaluation of the exercise.
---------------------
*) Note: In real cases often many animals to be
examined before sufficient quantity of adequate material suitable for
laboratory investigation is collected.
14) Selection and collection of specimen for
laboratory investigation
The exercise should include the selection and
collection of suitable specimen, its packing and preparation for shipment to
laboratory. Not always are available suitable specimens such as lesions
scrapings or epithelial flaps. In any case every participant should be trained
in extracting oesophageal-pharyngeal
fluid for laboratory investigations using
probang method.
15) Field
biological test on the spot
The simulations exercise under my
responsibility was usually ended by training in biological comparative test on
the spot which could be sometime useful before etiological diagnosis is
finalized. For the simulated test was usually used simulated inoculation (symbolically or using minimal
dosis of sterile physiological solution) into tongues of cattle, sheep or goat,
pig and horse. However, laboratory confirmation is always
necessary.
Note: Under real conditions
the inoculation of susceptible horses, swine and cattle (brought from region
distant from the outbreak) with suspect material may be helpful in differentiating
one vesicular disease from another. All three of the species are susceptible to
vesicular disease; cattle and swine are susceptible to FMD; swine alone respond to swine vesicular disease and
vesicular exanthema of swine. Vesicular stomatitis is a disease of horses,
cattle and swine.
16) Evaluation of
the exercise
a) Final day
should be dedicated to detailed critical analysis of the exercise and to
concrete evaluation of individual participant work commenting on eventual
deficiencies to be corrected. Availability of video pictures facilitates the
exercise evaluation.
b) The
suggestions for the intrafocal and perifocal measures to be discussed and
critically evaluated.
c) The participants should prove their new
competence by particular examination.
d)
The exercise should finish with certificate handover.
e) The exercise effectivity grade depends on
professional background and responsibility of the participants, competence and
experience of the teachers, training preparation, organization and management,
consistency of the implementation of all tasks, discipline of the participants,
local working conditions (mainly on the number of animals of different species
and categories for investigation), support of animal owners, etc.
Note:
The methodology of
FMD simulation practical field exercise can serve also as a model for similar
practical field simulation exercises directed to other very dangerous animal
diseases.
References
- BROADBENT, D.W. (Editor) (1984):
Las principales enfermedades exóticas de los animales y los sistemas
de respuesta de emergencia. Memoria de dos seminarios/simulacros subregionales
(en Colombia y Uruguay). Oficina Regional de la FAO para America Latina y el
Caribe, 98 pp.
- CALLIS, J.J. et al. (1982): Illustrated manual for the
recognition and diagnosis of certain animal diseases. Mexico-United States
Commission for the Prevention of Foot and Mouth Disease. p. 13-17.
- GAY GUTIÉRREZ, J. (1984): Ejercicios de
simulación y su importancia en el desarrollo y evaluación de los sistemas de
emergencia en salud animal. Oficina Regional de la FAO para America Latina y el
Caribe, 12 pp.
- OIE (2002): Foot and mouth disease: facing the new
dilemmas. Rev. sci. tech. Off. Int. Epiz., 21 (3), 498 pp.
- FAO (1982): Guión de un simulacro de campo realizado por el instituto
Colombiano Agropecuario con la cooperación de FAO. Oficina Regional de la FAO para America Latina y
el Caribe , 10 pp.
- FAO (1986): Report on seminar on simulation exercise for
foot-and-mouth disease control and eradication, 15-19 December 1986,
- FAO/EUFMD (1990): Report on
seminar on emergency action against foot-and-mouth disease (
- FAO/EUFMD (2001). Report on
the Joint EUFMD/EC Workshop on Foot-and-Mouth Disease Simulation Exercise, 5-7
June 2001,
- KOUBA, V. (1961): Analysis of foot-and-mouth disease in
- KOUBA, V. (1965):
Foot-and-mouth disease – differential diagnosis I. Veterináøství, XV, 6, 241-244 (in Czech).
- KOUBA, V. (1965):
Foot-and-mouth disease – differential diagnosis II. Veterináøství, XV, 10,
442-448 (in Czech).
- KOUBA, V. (1969):
Foot-and-mouth disease – differential diagnosis III. Veterináøství,
XIX, 6, 255-258 (in Czech).
- KOUBA, V.
(1985): Epizootiología general. Edición Pueblo y
Educación,
La Habana, 870 pp.
- KOUBA, V. (2012): Cursos
simulacros prácticos (en el campo) sobre fiebre aftosa. http://vaclavkouba.byl.cz/simulacros.ppt
- PANAFTOSA (1981) : Emergency
animal diseases eradication manual for the Caribbean with emphasis on
foot-and-mouth disease. PAHO, WHO, Brazil , 82 pp.
- PANAFTOSA (1981): Ejercicio
epidemiológico
de simulación
de un brote de fiebre aftosa. Acuerdo de frontera Argentina-Brasil-Uruguay,
- PANAFTOSA/SENASA (2005):
Simulacro de brote de fiebre aftosa, Cusco, Peru, 14-18 Febrero 2005.
More information on the principles of preventive and
control/eradication measures applicable on FMD see in http://vaclavkouba.byl.cz/textbook.htm.