Papers by Jeffrey Mariner
Summary This paper provides an ex-ante economic analysis comparing four alternative intervention ... more Summary This paper provides an ex-ante economic analysis comparing four alternative intervention strategies for the control and eradication of rinderpest against a scenario of no intervention in a cattle population similar in size to that of Ethiopia. The interventions were three different coverage levels of mass vaccination and one surveillance-based programme where vaccination targeted infected sub-populations. For each scenario, the
Summary Participatory epidemiology is the application of participatory methods to epidemiological... more Summary Participatory epidemiology is the application of participatory methods to epidemiological research and disease surveillance. It is a proven technique which overcomes many of the limitations of conventional epidemiological methods, and has been used to solve a number of animal health surveillance and research problems. The approach was developed in small-scale, community animal health programmes, and then applied to major
Preventive veterinary medicine, 2009
A participatory epidemiological (PE) study was carried out with Turkana pastoralists in Turkana S... more A participatory epidemiological (PE) study was carried out with Turkana pastoralists in Turkana South District, Kenya, to determine the relative incidence of livestock diseases and their impact on livelihoods. A sub-location was used as the sampling unit. A sub-location is the smallest administrative unit and is occupied by clusters of families (called adakars) that share common grazing patterns. A total of 32 sub-locations were randomly selected for the study. At least one focus group discussion involving more than 10 people was held with each adakar. In addition, key informant interviews involving local leaders and animal health service providers were conducted before or after the group sessions. PE techniques that were used with the stock owners include participatory mapping, relative incidence scoring, proportional piling, disease impact matrix scoring, seasonal calendars and probing. The methods used were pre-tested in four sub-locations that were excluded from further study. T...
PloS one, 2015
Contagious bovine pleuropneumonia (CBPP) is a cattle disease that has hampered the development of... more Contagious bovine pleuropneumonia (CBPP) is a cattle disease that has hampered the development of the livestock sector in sub-Saharan Africa. Currently, vaccination with a live vaccine strain is its recommended control measure although unofficial antimicrobial use is widely practiced. Here, modelling techniques are used to assess the potential impact of early elimination of infected cattle via accurate diagnosis on CBPP dynamics. A herd-level stochastic epidemiological model explicitly incorporating test sensitivity and specificity is developed. Interventions by annual vaccination, annual testing and elimination and a combination of both are implemented in a stepwise manner and their effectiveness compared by running 1000 simulations per intervention over ten years. The model predicts that among the simulated interventions, the ones likely to eliminate the disease from an isolated herd all involved annual vaccination of more than 75% of the animals with a vaccine that protects for a...
Preventive veterinary medicine, Jan 12, 2005
The development of a stochastic, state-transition model of rinderpest transmission dynamics is de... more The development of a stochastic, state-transition model of rinderpest transmission dynamics is described using parameter estimates obtained from both laboratory and participatory research. Using serological data, the basic reproduction numbers for lineage-1 rinderpest virus in southern Sudan and for lineage-2 rinderpest virus in Somali livestock were estimated as 4.4 and between 1.2 and 1.9, respectively. The model predictions for the inter-epidemic period in Sudan and Somalia (1.2 and 4.2 years, respectively) were in agreement with analysis of livestock-owner reports (1-2 years and 5 years, respectively).
Veterinary pathology, 1991
Ten goats were inoculated with peste des petits ruminants virus, a paramyxovirus closely related ... more Ten goats were inoculated with peste des petits ruminants virus, a paramyxovirus closely related to rinderpest virus. All goats developed severe clinical disease, 8/10 having coughing or dyspnea as prominent clinical signs. In addition, all of the goats had stomatitis and diarrhea. Histopathologic and immunohistochemical studies were done only on the respiratory tracts. Pathologic changes ranged from mild multifocal bronchiolitis and bronchitis to severe bronchointerstitial pneumonia. Lesions were more severe in anteroventral than caudal lobes. The histologic nature of the viral process in the goat lungs had many features in common with the processes of pneumonia in dogs, due to canine distemper, or pneumonia in human beings, due to measles virus. Immunohistochemical staining of formalin-fixed, paraffin-embedded respiratory tract tissue was performed using an indirect system with rabbit anti-rinderpest virus serum, biotinylated anti-rabbit antibody, streptavidin-alkaline phosphatase...
Summary The method of vaccine virus production, chemical stabilization, and lyophilization of a ... more Summary The method of vaccine virus production, chemical stabilization, and lyophilization of a thermostable Vero cell-adapted rinderpest vaccine is presented. The production method results in a vaccine which can be used in the field without refrigeration for up to 30 d.
International Journal of Infectious Diseases, 2008
Epidemiology and Infection, 2014
We conducted an operational research study involving backyard and semicommercial farms on Java Is... more We conducted an operational research study involving backyard and semicommercial farms on Java Island, Indonesia, between April 2008 and September 2009 to evaluate the effectiveness of two preventive mass vaccination strategies against highly pathogenic avian influenza (HPAI). One regimen used Legok 2003 H5N1 vaccine, while the other used both Legok 2003 H5N1 and HB1 Newcastle disease (ND) vaccine. A total of 16 districts were involved in the study. The sample size was estimated using a formal power calculation technique that assumed a detectable effect of treatment as a 50% reduction in the baseline number of HPAIcompatible outbreaks. Within each district, candidate treatment blocks with village poultry populations ranging from 80 000 to 120 000 were created along subdistrict boundary lines. Subsequently, four of these blocks were randomly selected and assigned one treatment from a list that comprised control, vaccination against HPAI, vaccination against HPAI + ND. Four rounds of vaccination were administered at quarterly intervals beginning in July 2008. A vaccination campaign involved vaccinating 100 000 birds in a treatment block, followed by another 100 000 vaccinations 3 weeks later as a booster dose. Data on disease incidence and vaccination coverage were also collected at quarterly intervals using participatory epidemiological techniques. Compared with the unvaccinated (control) group, the incidence of HPAI-compatible events declined by 32% (P = 0.24) in the HPAI-vaccinated group and by 73% (P = 0.00) in the HPAI-and ND-vaccinated group. The effect of treatment did not vary with time or district. Similarly, an analysis of secondary data from the participatory disease and response (PDSR) database revealed that the incidence of HPAI declined by 12% in the HPAI-vaccinated group and by 24% in the HPAI + ND-vaccinated group. The results suggest that the HPAI + ND vaccination significantly reduced the incidence of HPAI-compatible events in mixed populations of semicommercial and backyard poultry.
Tropical Animal Health and Production, 1991
Preventive Veterinary Medicine, 2006
Pastoral cattle live in highly structured communities characterized by complex contact patterns. ... more Pastoral cattle live in highly structured communities characterized by complex contact patterns. The present paper describes a spatially heterogeneous model for the transmission of contagious bovine pleuropneumonia (CBPP) developed specifically for pastoral communities of East Africa. The model is validated against serological data on the prevalence of CBPP infection in several communities of southern Sudan and against livestock owner information on community structure, livestock contact and cattle exchange. The model is used to assess the impact of alternative control strategies including mass and elective vaccination programmes, potential treatment regimes and the www.elsevier.com/locate/prevetmed Preventive Veterinary Medicine 73 combination of vaccination and treatment in a single unified strategy. The results indicate that the eradication of CBPP using mass vaccination with currently available vaccines is unlikely to succeed. On the other hand, elective control programmes based on herd level vaccination, treatment of clinical cases or a combination of both vaccination and treatment enabled individual livestock owners to capture a large benefit in terms of reduced animal-level prevalence and mortality experience. The most promising intervention scenario was a programme which combined the vaccination of healthy animals with treatment of clinical cases. # 2005 Published by Elsevier B.V.
Preventive Veterinary Medicine, 2006
The dynamics of contagious bovine pleuropneumonia (CBPP) transmission vary widely between livesto... more The dynamics of contagious bovine pleuropneumonia (CBPP) transmission vary widely between livestock production systems. This paper describes the development of a homogeneous, stochastic, compartmental model for CBPP transmission in pastoral herds of East Africa. The model was built using parameter estimates based on data published in the literature and on observations of livestock owners obtained through participatory research. The basic reproduction number for CBPP in southern Sudan was estimated to range from 3.2 to 4.6. The homogeneous model indicates that the critical community size for the persistence of CBPP falls within the typical herd sizes for pastoral communities in East Africa suggesting that individual isolated herds are capable of maintaining infection indefinitely. Vaccination alone with currently available vaccines was unlikely to eradicate the disease. # 2005 Published by Elsevier B.V.
Philosophical Transactions of the Royal Society B: Biological Sciences, 2013
Veterinary Microbiology, 1990
A lyophilized thermostable Vero cell-adapted ringerpest vaccine, stabilized with lactalbumin hydr... more A lyophilized thermostable Vero cell-adapted ringerpest vaccine, stabilized with lactalbumin hydrolysate and sucrose, was tested for safety, serological response and suitability for use with an abbreviated cold chain under field conditions in Niger. A total of 480 cattle, 90 goats and 55 sheep of unknown serological status were vaccinated on government ranches and observed for at least 22 days. No untoward effects of the vaccine were detected. The serological response to the vaccine stored at environmental temperatures for 30 to 34 days was determined in 144 previously unvaccinated yearling calves. Seroconversion was demonstrated in 98% of the yearling calves using seroneutralization. The un-refrigerated vaccine retained a titer of 3.69 log10 TCID50 per dose through day 34.
Veterinary Microbiology, 1990
The thermostability of a rinderpest vaccine produced on Vero cells was evaluated using a variety ... more The thermostability of a rinderpest vaccine produced on Vero cells was evaluated using a variety of chemical stabilizers and lyophilization protocols. Three stabilizer preparations and three lyophilization schedules were examined using accelerated stability testing at 37 degrees C. The vaccine preparation exhibiting the greatest stability at 37 degrees C was tested at three additional temperatures, 42, 45 and 56 degrees C, and an Arrhenius plot was constructed from the data. The stability of the reconstituted vaccine produced with the two most efficacious stabilizers was examined using three different diluent preparations. The stabilization method and high Vero cell virus batch titers resulted in a lyophilized vaccine which maintained the minimum required dose of log10 2.5 TCID50 tissue culture infectious dose for more than 20 weeks at 37 degrees C.
The Veterinary record, Jan 2, 2011
... Paul Rossiter, formerly adviser to the Pan-African Rinderpest Campaign9 and; William Taylor, ... more ... Paul Rossiter, formerly adviser to the Pan-African Rinderpest Campaign9 and; William Taylor, formerly adviser to the Pan-African ... Heath Lodge, Lucas Green Road, West End, Woking, Surrey GU24 9LD, UK; Institute for Animal Health, Pirbright Laboratory, Ash Road, Pirbright ...
Epidemiology and Infection, 2009
In developing countries, vaccination against highly pathogenic avian influenza subtype H5N1 (HPAI... more In developing countries, vaccination against highly pathogenic avian influenza subtype H5N1 (HPAI) in free-range poultry flocks is usually implemented as periodic campaigns and newborn chicks are generally not vaccinated by farmers between vaccination passes. The demographic population turnover leads to a continuous decrease in the population immunity rate (PIR) over time. We present a simple Leslie matrix model for estimating population turnover and PIR dynamics in a hypothetical small-size vaccinated free-range poultry population. Four different vaccination scenarios were identified assuming necessary procedures to achieve immunity. The results indicate that high levels of population immunity are difficult to sustain. Assuming an animal immunity response of 80% after vaccination and a constant population size, PIR 4 months after vaccination was 30% in all the scenarios. Predictions averaged over time showed mean PIR between 36% and 48%, which is below the population immunity thresholds for eradication approximated from R0 estimates.
Journal of Tissue Culture Methods, 1991
Summary The method of vaccine virus production, chemical stabilization, and lyophilization of a ... more Summary The method of vaccine virus production, chemical stabilization, and lyophilization of a thermostable Vero cell-adapted rinderpest vaccine is presented. The production method results in a vaccine which can be used in the field without refrigeration for up to 30 d.
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Papers by Jeffrey Mariner