4. Discussion
The study is one of the larger scale surveys of the knowledge,
attitudes, and practices (KAP) of Cambodian smallholder livestock
farmers on cattle health and production issues, providing information on
FMD management and vaccination programs. The study intended to identify
opportunities for improving the uptake of FMD vaccination and
implementing biosecurity interventions in rural communities. The study
identified that although smallholder farmers undertake a range of
farming and off-farming activities, large ruminants contribute a large
proportion of total household income (KC 30%; PS 25%) at the rural
community level (Ashley et al., 2018;
Samkol et al., 2015) and deserve
investments to mitigate disease risk, despite the majority of surveyed
farmers still practicing the traditional method of cattle raising.
Although all cattle in the household herd were tethered under the house
during the night, as they are commonly permitted to graze on available
pastures, paddy fields and shrubs or common grassland areas further from
the village, there are ample opportunities for disease transmission
within and between large ruminant village populations, as previously
reported (Kawasaki, Young, Suon, Bush, &
Windsor, 2015).
With most farmers using communal grazing method, the movement of large
ruminants to communal grazing areas enables contact with animals from
other locations, increasing the risk of contracting diseases,
particularly FMD, as previously reported by other studies
(Chamnanpood, Cleland, Baldock, & Gleeson,
1995; Cleland, Chamnanpood, Baldock, &
Gleeson, 1995), and recently reviewed by
(Blacksell et al., 2019). During FMD
outbreaks, confining and feeding cattle on cut grasses reduces the
likelihood of infection, with this practice proposed to reduce the risk
of spread of FMD virus by reducing the direct contact between healthy
and infected animals (Cleland, Baldock,
Chamnanpood, & Gleeson, 1996). The growing of improved grass forage
species has achieved positive production and socioeconomic outcomes
(Stur et al., 2002;
Young et al., 2014a;
Young et al., 2014b) and if more widely
adopted, a higher proportion of farmers employing cut and carry (stall
feeding) to raise their animals will help reduce the risk of FMD
transmission, improving rural livelihoods
(Nampanya et al., 2015).
FMD was rated as a significant factor affecting livestock production by
the surveyed farmers with most appearing to know and recognize FMD
clinical signs and understand the main purpose of vaccination. Farmers
revealed that people within the village were the most preferred persons
to communicate new cases of diseases, indicating that the farmer disease
communication network generally remained local. Local authorities such
as district or provincial veterinarians were not acknowledged as
important contact persons by the majority of farmers. This implies that
VAHWs should have a more important role in assisting disease
surveillance by receiving disease information from farmers and rapidly
conveying this information to the district and provincial veterinary
officials and local authorities for the disease intervention, as
described by others (MacPhillamy et al.,
2020; Stratton et al., 2015). However,
as disease reporting is most effective when followed by a rapid disease
response, particularly after the index case in the outbreak,
strengthening of the role of the VAWH requires considerable effort in
disease response training (MacPhillamy et
al., 2020). Emergency disease reporting, investigation and response in
Cambodia remain a critical weakness in FMD disease prevention and
control (Blacksell et al., 2019;
MacPhillamy et al., 2020), with the lack
of urgency in FMD reporting indicating that many stakeholders tend to
think FMD is not a serious disease due to low fatality rate
(Sieng & Kerr, 2013).
The study found that three-quarters of interviewed farmers did not
isolate the first FMD infected animal from the household herd, resulting
in all cattle in the herd developing the disease. Of those who separated
their ill animals, many of them only separated infected cattle during
the day and usually regrouped them after the livestock returned from the
grazing areas, as was identified in previous studies
(Christley, Robinson, Lysons, & French,
2005; Gleeson, 2002;
Sumption, Rweyemamu, & Wint, 2008). In
rural communities, it is unlikely that smallholder farmers would have a
safe alternative place at night to isolate the first infected animal and
consider they have no choice but to keep all animals together at night.
However, the poor knowledge and understanding of disease transmission
and biosecurity practices of farmers identified in this and other
studies indicate the enormous challenge facing animal health programs
that aim to achieve FMD control in Cambodia and beyond
(Blacksell et al., 2019;
Kerr, Sieng, & Scoizec, 2012;
Perry et al., 2002;
Rast, Windsor, & Khounsy, 2010;
Sieng & Kerr, 2013;
Windsor et al., 2008;
Young et al., 2012).
During the outbreaks, treatment was identified to be the first
intervention preference for the majority of farmers, seeking treatment
services from VAHWs (72%), with some more knowledgeable farmers
commencing the treatment of FMD infected cattle by themselves (53%)
with the assistance from relatives, friends, and neighbors. It is a
Cambodian custom, especially in remote communities, to assist each other
to restrain and treat infected cattle and this strong rural cultural
practice is indicative of good communal relationships, although
increases FMD transmission risk without improved hygiene practices. Most
of the surveyed farmers reported that the majority of neighboring
farmers’ cattle were also sick during the outbreak offering assistance
before (57%) or after (43%) their cattle got infected with FMD.
Even though farmers appear to have some knowledge of FMD, it is
disturbing that they were unaware that the risk of FMD spread via their
movements, contaminated clothing, hands and feet equipment to livestock
in other households is considerable. During an FMD outbreak, the social
visits from family members, neighbors, and friends were reported to have
contributed 25% of contacts with animals
(Nielen et al., 1996). Several studies in
developing countries revealed that the movement of people including
traders, village chiefs, extension staff between villages and movement
of animals from different villages in grazing areas is reported to be
significant risk factors for the spread of FMD
(Hunter, 1998;
Kerr et al., 2012;
Khounsy et al., 2008;
Perry et al., 2002;
Sumption et al., 2008).
The sale and purchase of infected animals were not reported by the
majority of farmers in this study, although it is suspected that farmers
preferred not to admit to this practice, particularly as compliance with
restrictions on livestock trade and movements during the outbreaks is
considered poor, with both infected and dead animals likely to be traded
with local traders and local slaughterhouses. Trading of FMD infected
animals during FMD outbreaks appears to be ongoing practice within rural
communities in Cambodia, leading to the persistence of annual FMD
outbreaks, with a morbidity rate exceeding 30% revealed in this study.
High morbidity rates up to 74% were identified in an unvaccinated
village in Lao PDR (Rast et al., 2010).
Previous studies with traders in Cambodia confirmed that farmers did
sell sick livestock to avoid animals dying and to salvage some animal’s
value before death, and animal owners were more likely to sell sick
animals, and more stock was available when diseases were prevalent in an
area (Sieng, Hawkins, Madin, & Kerr,
2012; Young et al., 2014c).
Interestingly, more than half of traders admitted that they had traded
FMD infected animals, due to the low prices accepted by farmers for sick
animals (Kerr et al., 2012;
Sieng et al., 2012) although a survey of
traders identified their preference for FMD vaccinated animals
(Young et al., 2014c). Previous studies
have consistently identified that the movement of infected animals and
animal products are the most important factors increasing the spread of
disease (Blacksell et al., 2019;
Christley et al., 2005;
Perry et al., 2002;
Sumption et al., 2008;
Young et al., 2014c). Lack of basic KAPs
on disease transmission and biosecurity by farmers and other
stakeholders at the village level remains a major concern for the
veterinary authorities attempting to control a most infectious disease
such as FMD.
In Cambodia, FMD control has relied only on ring vaccination around
outbreaks. This study identified that over three-quarters of farmers
(79%) had not vaccinated their cattle against FMD during the previous
three years. Of those vaccinated, most cattle were vaccinated by VAHWs
once every year or once in three years, and booster FMD vaccination had
not been administered, as is recommended by vaccine manufacturers
(Doel, 2003). This study found that only a
small proportion of cattle in each village were vaccinated, suggesting
that effective herd immunity was not achieved, as this would likely
require at least 75% (Lombard &
Schermbrucker, 1993) to 80% (Chamnanpood,
Gleeson, & Robertson, 1993; Jori et al.,
2009) of the population to be effectively vaccinated. Ring vaccination
of all susceptible animals implemented with sanitary measures had been
proposed as a means to reduce the spread and shorten the outbreak
duration (Barteling & Vreeswijk, 1991). A
case study of an FMD outbreak in Lao PDR
(Rast et al., 2010) indicated that
vaccinating the whole large ruminant population reduced the losses from
FMD per animal by a factor of about four times compared to vaccinating
only just over half the population.
In this study, the farmers identified that their most important reasons
for not vaccinating were an unwillingness to pay for vaccination when
their cattle were healthy and that they had not received information
about vaccination. This finding indicates that the majority of farmers
had a poor understanding of the usefulness and importance of
vaccination, tend to rely entirely on free FMD vaccines supported by the
veterinary authorities as a private FMD vaccination service was
unavailable during the study period. As many farmers still perceive FMD
as being far less important than other diseases due to the low mortality
rate, private vaccination services may be more difficult to implement
compared to other higher mortality diseases, such as Haemorrhagic
Septicaemia (Kawasaki et al., 2015).
Poorly delivered vaccination campaigns also contribute to the low
vaccination coverage even when the vaccine is available. This is not
surprising, considering FMD vaccination delivery was based on government
support, and the finding likely reflects those study villages may have
been excluded from the list of villages vaccinated under the provincial
FMD vaccination plan.
The multivariable logistic regression analysis indicates that age,
education, number of household members livestock management and
husbandry were not associated with the FMD vaccination practices of
farmers. However, farmers reporting their cattle were vaccinated by a
VAHW through a government-subsidized vaccination, indicated they were
more likely to have their cattle vaccinated for FMD than those who did
not avail themselves of VAHWs’ services. The numerous issues arising
with the delivery of large scale regional FMD vaccination programs over
several years in the GMS have been identified and reported from Lao PDR
(Blacksell et al., 2019;
Nampanya, Khounsy, Abila, & Windsor,
2018).
Although FMD is not perceived as high mortality risk in most outbreaks
(less than 1% in this study), the disease is highly infectious and
debilitating, leading to significant economic losses for individual
farming families, plus village, provincial and national levels
(Nampanya et al., 2015;
Young et al., 2014b;
Young et al., 2012;
Young et al., 2017). The economic impacts
of FMD were identified in our study, with 8 of the participating farmer
households having lost approximately one-third of their household herd
during the most recent FMD outbreak. Several studies on the impact of
FMD indicated that regular FMD outbreaks cause economic hardship for
farmers due to loss of cattle body weight
(Young et al., 2012), loss of production
and/or death of affected animals (Muleme
et al., 2012) and reduced sale value
(Muleme et al., 2012;
Perry et al., 2002;
Young et al., 2012). Most of the
interviewed farmers realized that the cost of treatment is much higher
than the full fee bi-annual FMD vaccination, with some farmers likely
wishing to pay for the private FMD vaccination services from the local
VAHWs (Stratton et al., 2015), although
FMD vaccines were rarely available.
However, a major reason contributing to the absence of private FMD
vaccination services and the challenge of addressing the need for
improved biosecurity change management
(Young, Evans‐Kocinski, Bush, & Windsor,
2015), is the likely farmer resistance following the long-standing
practice of farmers receiving and expecting government-subsidized FMD
vaccination. It is a challenging task for the DAHP and POAHP to convince
farmers to change their attitudes and practices towards FMD vaccination
and encourage them to participate and accept full fee-based FMD
vaccination services for their cattle.
Thus, the quality of vaccination campaign delivery and extensive farmer
training is essential in moving the rural Cambodian community to accept
the inevitably of self-funding vaccination that can be delivered by
private vaccination services in their communities. If the effectiveness
of vaccination delivery can be improved and cattle can be protected
during outbreaks, with adequate training to motivate farmers and
overcome their resistance to change, the recognition that full fee
bi-annual FMD vaccination is an important measure to protect cattle from
FMD is perhaps achievable. As the study identified the average cost of
treatment plus nursing a sick animal (USD41.00) was more than 10 times
the cost of full fee bi-annual FMD vaccination (USD3.00), this
information can form the basis of future extension programs on FMD
management.
The feasibility of delivery and the potential success of TAD control
measures, including vaccination programs, depends on the cooperation of
farmers with local authorities at the village level, although provincial
and national level service providers, international donors and
stakeholders are also of relevance. A significant educational effort on
vaccination and biosecurity is required to explain the benefits that
disease risk management provides. Existing FMD control strategies,
especially FMD vaccination delivery in Cambodia, require review, with
appropriate surveillance and emergency response capabilities upgraded to
enable provincial and central level services to enhance their abilities
to reduce the occurrence of FMD outbreaks and improve the uptake of FMD
vaccination. Full fee-based FMD vaccination services should be
considered and introduced in rural communities by the veterinary
authorities, although this requires that GDAHP and POAHP discuss this
new concept with the VAHWs and village chiefs that will be essential in
assisting extension workers in promotion of the vaccination campaign and
ensuring farmers well understand the cost-benefits of full fee bi-annual
FMD vaccination.
This field survey involved 300 smallholder farmers, although there is
usually an issue with the accuracy of some responses as interviewed
stakeholders may be reluctant to provide correct and true information if
they know it is against the existing government or social policy.
Further studies on the benefit and cost analysis of fee-based bi-annual
FMD vaccination are required for the future improvement of FMD
vaccination uptake as well as the FMD control program in Cambodia.
Further, research questions to identify the cost and benefits of
combined cattle health and production programs that include establishing
forage with stall feeding, persistent vaccination and deworming
programs, and importantly biosecurity including movement control, should
be prioritized for future research study in Cambodia.