Lessons for rabies control and elimination programmes: a decade of One Health experience from Bali, Indonesia.

Since the emergence of rabies on Bali, Indonesia, in 2008, the Indonesian Government and other stakeholders have implemented disease control and prevention activities with the aim of re-securing Bali's freedom from dog-mediated rabies. The authors report on the lessons learned during these efforts, and their applicability to other regions where canine rabies is endemic, as well as to rabies-free populations that are at risk from incursions. To eliminate rabies from Bali will require time and commitment, as well as a combination of approaches employing the principle of One Health. Efforts should be directed towards well-coordinated, highcoverage, annual dog vaccination campaigns using high-quality vaccines, and enhanced surveillance focused on investigations of biting animals. Bali, an island, is an ideal target for achieving freedom from rabies, but the logistics of vaccinating its very large, free-roaming dog population are challenging. Lessons can be drawn from Bali for other large and dense dog populations, where dog management and rabies control appear difficult. Well-trained teams with nets can rapidly catch and vaccinate large numbers of dogs where central-point vaccination is insufficient, and post vaccination surveys of collared dogs can be used to evaluate coverage and target supplementary vaccination. However, careful planning is required to ensure that all communities are reached during such campaigns and that sufficient vaccine is available over the following years. Effective communication strategies are needed to coordinate intersectoral activities, and to keep communities engaged, particularly during the 'end game', when the risk of rabies appears only minimal. An effective One Health approach to eliminate rabies requires long-term planning, multisectoral communication and coordination, and sustained effort, using tried and tested methods.

Suite à l'émergence de la rage à Bali (Indonésie) en 2008, le gouvernement indonésien et d'autre parties prenantes ont introduit des mesures de contrôle et de prévention de la maladie afin de sécuriser le statut précédemment indemne de Bali au regard de la rage transmise par les chiens. Les auteurs font le point sur les enseignements tirés de cette expérience et évaluent sa pertinence pour d'autres régions, par exemple celles où la rage canine est endémique ou qui possèdent des populations indemnes de rage mais exposées au risque d'une incursion du virus. L'élimination de la rage à Bali est une entreprise qui prendra du temps et exigera une grande détermination ainsi que le recours combiné à diverses méthodes suivant les principes Une seule santé. Les efforts devront s'orienter vers des campagnes annuelles de vaccination des chiens, qu'il faudra coordonner avec soin en assurant une couverture élevée et en faisant appel à des vaccins de haute qualité, et vers une surveillance accrue avec notamment l'investigation de tout chien responsable de morsure. De par son insularité, Bali constitue un territoire idéal pour réussir l'élimination totale de la rage, mais la logistique requise pour la vaccination est lourde, en plus du défi majeur que posent les effectifs importants de chiens errants. Les leçons tirées de l'expérience de Bali peuvent se révéler fructueuses dans d'autres régions dotées de populations canines denses et nombreuses et où les opérations de gestion de ces populations et de lutte contre la rage se présentent sous un jour peu favorable. Dans les contextes où il n'y a pas suffisamment de centres de vaccination, les chiens peuvent être capturés et vaccinés en grand nombre par des équipes bien entraînées et disposant de filets, tandis que le suivi post-vaccinal des chiens enregistrés offre un bon moyen d'évaluer la couverture vaccinale et de cibler les besoins supplémentaires. Il est essentiel de bien planifier ces campagnes afin de s'assurer qu'elles ont touché toutes les communautés et que les stocks de vaccins sont suffisants pour les années à venir. Des stratégies efficaces de communication sont nécessaires pour coordonner les activités intersectorielles et pour maintenir le niveau de motivation des communautés, en particulier en fin de campagne car les risques de rage sont alors perçus comme étant minimes. Pour être efficace, une approche Une seule santé d'élimination de la rage requiert une planification sur le long terme, une communication multisectorielle et des efforts de longue haleine recourant à des méthodes éprouvées.

Desde que en 2008 la rabia hizo su aparición en Bali (Indonesia), el Gobierno del país y otras partes interesadas han llevado a cabo una serie de actividades de control y prevención de la enfermedad con el objetivo de devolver a la isla la condición de «libre de la rabia transmitida por perros¼. Los autores dan cuenta de las enseñanzas extraídas de esta labor y examinan la viabilidad de aplicarlas a otras regiones donde la rabia canina es endémica, así como a poblaciones libres de rabia que corren peligro de sufrir incursiones de la enfermedad. Para eliminar la rabia de Bali hará falta tiempo y dedicación, así como una combinación de métodos regida por los principios de Una sola salud. Convendría centrar el trabajo en campañas anuales de vacunación de perros bien coordinadas, de amplia cobertura y realizadas con vacunas de gran calidad, que se acompañen de una vigilancia más intensa centrada en la investigación de los casos de animales mordedores. Por su condición insular, Bali ofrece condiciones idóneas para lograr la eliminación de la rabia, pero la logística de las vacunaciones es muy aparatosa y las poblaciones de perros vagabundos plantean grandes problemas. De la experiencia balinesa cabe extraer enseñanzas útiles para otras zonas que albergan poblaciones de perros amplias y densas, donde la gestión de estas poblaciones y la lucha antirrábica parecen resultar dificultosas. Allí donde la vacunación centralizada no baste, cabe desplegar equipos bien formados y provistos de redes que puedan capturar y vacunar rápidamente a un gran número de perros, empleando después, eventualmente, estudios posvacunales de los perros con collar identificativo para evaluar la cobertura y seleccionar objetivos de vacunación complementaria. Sin embargo, para llegar a todas las comunidades en el curso de tales campañas y tener la seguridad de disponer de un suministro suficiente de vacunas en los años subsiguientes hace falta una minuciosa planificación. Se necesitan asimismo dispositivos eficaces de comunicación para coordinar las actividades intersectoriales, y también hay que mantener movilizadas a las comunidades, especialmente en la fase final, cuando el riesgo de rabia parece ser mínimo. Todo método eficaz de eliminación de la rabia que parta de los postulados de Una sola salud exige planificación a largo plazo, comunicación y coordinación multisectoriales y una labor sostenida, con empleo de métodos de probada y contrastada eficacia.

Antibody response and risk factors for seropositivity in backyard poultry following mass vaccination against highly pathogenic avian influenza and Newcastle disease in Indonesia.

A large-scale mass vaccination campaign was carried out in Java, Indonesia in an attempt to control outbreaks of highly pathogenic avian influenza (HPAI) in backyard flocks and commercial smallholder poultry. Sero-monitoring was conducted in mass vaccination and control areas to assess the proportion of the target population with antibodies against HPAI and Newcastle disease (ND). There were four rounds of vaccination, and samples were collected after each round resulting in a total of 27 293 samples. Sampling was performed irrespective of vaccination status. In the mass vaccination areas, 20-45% of poultry sampled had a positive titre to H5 after each round of vaccination, compared to 2-3% in the control group. In the HPAI + ND vaccination group, 12-25% of the population had positive ND titres, compared to 5-13% in the areas without ND vaccination. The level of seropositivity varied by district, age of the bird, and species (ducks vs. chickens).

Avian Influenza A(H5N1) Virus Outbreak Investigation: Application of the FAO-OIE-WHO Four-way Linking Framework in Indonesia.

WHO, FAO and OIE developed a 'four-way linking' framework to enhance the cross-sectoral sharing of epidemiological and virological information in responding to zoonotic disease outbreaks. In Indonesia, outbreak response challenges include completeness of data shared between human and animal health authorities. The four-way linking framework (human health laboratory/epidemiology and animal health laboratory/epidemiology) was applied in the investigation of the 193 rd human case of avian influenza A(H5N1) virus infection. As recommended by the framework, outbreak investigation and risk assessment findings were shared. On 18 June 2013, a hospital in West Java Province reported a suspect H5N1 case in a 2-year-old male. The case was laboratory-confirmed that evening, and the information was immediately shared with the Ministry of Agriculture. The human health epidemiology/laboratory team investigated the outbreak and conducted an initial risk assessment on 19 June. The likelihood of secondary cases was deemed low as none of the case contacts were sick. By 3 July, no secondary cases associated with the outbreak were identified. The animal health epidemiology/laboratory investigation was conducted on 19-25 June and found that a live bird market visited by the case was positive for H5N1 virus. Once both human and market virus isolates were sequenced, a second risk assessment was conducted jointly by the human health and animal health epidemiology/laboratory teams. This assessment concluded that the likelihood of additional human cases associated with this outbreak was low but that future sporadic human infections could not be ruled out because of challenges in controlling H5N1 virus contamination in markets. Findings from the outbreak investigation and risk assessments were shared with stakeholders at both Ministries. The four-way linking framework clarified the type of data to be shared. Both human health and animal health teams made ample data available, and there was cooperation to achieve risk assessment objectives.

The effectiveness of preventative mass vaccination regimes against the incidence of highly pathogenic avian influenza on Java Island, Indonesia.

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 HPAI-compatible 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.

A survey of zoonotic diseases in trade cattle slaughtered at Tanga city abattoir: a cause of public health concern.

OBJECTIVE: To estimate the prevalence of hydatidosis, cysticercosis, tuberculosis, leptospirosis, brucellosis and toxoplasmosis in slaughtered bovine stock (aged ±3 years) at Tanga city abattoir, Tanzania. METHODS: Prevalence estimation of the five zoonotic diseases was undertaken through an active abattoir and sero-survey was carried out in Tanga city, during the period of January 2002 and March 2004. Serum samples collected from a sub-sample (n=51) of the slaughter stock were serologically screened for antibodies against brucellosis, leptospirosis and toxoplasmosis using Rose Bengal plate test, microscopic agglutination test (for 5 serovars of Leptospira interrogans) and Eiken latex agglutination test, respectively. The same animals were tested for tuberculosis using the single intradermal tuberculin test. RESULTS: Post mortem examination of 12 444 slaughter cattle (10 790 short horn zebu and 1 654 graded) over a period of twenty two months, showed a prevalence of 1.56% (194) for hydatidosis, 1.49% (185) for cysticercosis and 0.32% (40) for tuberculosis. In all three zoonoses, a statistically significant difference in infection rates was noted between the short horn zebu and graded breeds (P<0.05). The overall seroprevalences of animals with brucellosis, toxoplasmosis and leptospirosis antibodies were found to be 12%, 12% and 51%, respectively. The most common leptospiral antibodies detected were those against antigens of serovars Leptospira hardjo (29%), Leptospira tarassovi (18%), Leptospira bataviae (4%) and Leptospira pomona (0%). With regard to tuberculosis, 10% (n=5) of the animals tested were classified as non-specific reactors or inconclusive. CONCLUSIONS: The study findings suggest that brucellosis, toxoplasmosis and leptospirosis are prevalent in Tanga and provide definitive evidence of slaughtered stock exposure to these zoonotic agents with concurrent public health consequences.

Microbial quality and associated health risks of raw milk marketed in the Tanga region of Tanzania.

OBJECTIVE: To evaluate microbial quality and associated health risks of raw milk marketed in the Tanga region of Tanzania. METHODS: A microbial quality assessment of marketed raw milk was undertaken by evaluating 59 samples of milk from selling points (collecting centres =15), bicycle boys (12) and kiosks/restaurants (32) in Tanga city during April-May 2005. Quality and milk-borne hazards were assessed using a combination of tests in order to quantify the occurrence of Brucellosis (milk ring test), Escherichia coli (E. coli) O157:H7 (culture), the coliform bacteria as well as standard plate count (SPC). Specific gravity (SG) determination was used as an indicator of adulteration. RESULTS: The mean coliform plate count (c.f.u/mL) of milk handled by bicycle boys (4.2×10(6)) was significantly higher than that handled by collecting centres (3.0×10(6)) and kiosk/ restaurants (1.4×10(6)), respectively (P < 0.05). Of the 59 milk samples collected, 33 (56%) were Brucella milk ring test (MRT)-positive and 78% and 17% of the samples graded satisfactorily based on SG and coliform plate counts as prescribed by East African Community standards for raw milk. There was no verocytotoxigenic E. coli (VTEC) O157: H7 in any of the milk samples collected and analysed during the present study. CONCLUSIONS: It can be concluded that raw market milk in the study area is of poor bacteriological quality and hazardous for human consumption. This highlights the need to implement good hygiene practices and effective monitoring from production through the delivery chain to the consumer. Further studies are needed for detection of toxins that are produced by E. coli, other pathogenic spore forming bacteria (Bacillus spp. and Clostridium spp.) and other harmful microorganisms.

Herd- and animal-level risk factors for bovine leptospirosis in Tanga region of Tanzania.

Leptospirosis is the zoonosis of worldwide distribution and common cause of economic loss and ill health among animals and human populations. A cross-sectional seroprevalence study, using a microscopic agglutination test (MAT) with a threshold titre of >or=1:160, to elucidate disease magnitude, distribution and associated risk factors in cattle in Tanga, Tanzania was conducted from May 2003 to January 2004. Serum (n = 655) samples collected from randomly selected herds (n = 130) were tested for antibodies against four different Leptospira interrogans serovars (Bataviae, Tarassovi, Hardjo and Pomona) used in the agglutination test. Positive titres were detected in 30.3% [95% confidence intervals (CI) = 26.7-33.9] of cattle and 58.5% (95% CI = 49.5-67.1) of herds, respectively. Of the 198 MAT positive serum samples, 98 (49.5%) were positive against serovar Hardjo, 80 (40.4%) were positive against serovar Tarassovi, 12 (6.1%) was positive against serovar Bataviae and eight (4%) were positive against serovar Pomona. Associations found to be statistically significant in univariate analyses (at P < 0.1) were assessed by multivariable logistic regression to control for confounding factors. The results showed that risk factors for cattle were pasture grazing [odd ratio (OR) = 2.83, 95% CI = 1.57-5.12, P = 0.001], presence of goats/sheep on the farm (OR = 1.73, 95% CI = 1.17-2.56, P = 0.001) and age of the animal (OR = 2.05, 95% CI = 1.42-2.96, P = 0.001), while concrete floor housing was protective (OR = 0.47, 95% CI = 0.30-0.74, P = 0.001). Herds managed under pasture grazing system were more likely to be sero-positive than those managed under zero grazed practices (OR = 9.31; 95% CI = 3.67-23.64 for grazing herd). We concluded that bovine leptospirosis is an endemic and locally widespread disease in Tanga and suggest that it may play a role in zoonotic transmission to humans.

Risk factors associated with the seroprevalence of leptospirosis, amongst at-risk groups in and around Tanga city, Tanzania.

The epidemiological status of human leptospirosis in Tanzania has not been well defined because of a general lack of awareness of the disease and difficulties in its diagnosis. A cross-sectional seroprevalence study, using the microscopic agglutination test with a threshold titre of 1 : 160, was therefore conducted, among various occupational groups from Tanga city, in November 2005. Of the 199 subjects investigated, 30 (15.1%) were found to have antibodies that reacted with antigens from at least one of the six Leptospira interrogans serovars used in the agglutination test. Of the seropositive samples, 36.6% were positive for serovar Icterohaemorrhagiae, 30.0% for Bataviae, 20.0% for Hardjo, 6.6% for Tarrassovi, 3.3% for Ballum and 3.3% for Pomona. Amongst the occupational groups examined, livestock farmers, veterinary/meat inspectors and abattoir workers appeared to be most at risk, with seroprevalences of 19.4%, 18.1% and 17.1%, respectively. Subjects who reported that they milked cows were significantly more likely to be found seropositive for Leptospira infection than the other subjects (odds ratio=3.44; P<0.001). These findings indicate that a significant proportion of the population of Tanga city is being exposed to pathogenic Leptospira. Public-health interventions against leptospirosis will need to target not only the occupational groups considered to be at high risk of infection but also the general population at large.

Seroprevalence of Toxoplasma gondii infection amongst residents of Tanga district in north-east Tanzania.

Toxoplasmosis is a zoonotic disease, recognized as a serious public health problem worldwide. Toxoplasma gondii infection has become a major public health concern in recent years due to the ravaging HIV/AIDS pandemic. A serological survey was carried out in Tanga district of north-eastern Tanzania to assess T. gondii infection rates among occupationally-exposed groups including abattoir workers, livestock keepers, animal health workers and other groups. The survey was undertaken in November 2005 using modified Eiken latex agglutination test (LAT). Antibodies to T. gondii were detected in 91 (46%) of the 199 individuals studied. T. gondii seroprevalence was slightly higher amongst males (46.2%) than females (43.3%) although the difference was not significant (P > 0.05). Individuals, < or =20 and > or =60 years old had the highest prevalence of 60% and 61.5%, respectively. The lowest prevalence of (35.7%) was observed amongst the 50-60 years age group. The seroprevalence of toxoplasma antibodies was significantly higher amongst individuals who keep livestock (52.2%) and abattoir workers (46.3%). These results suggest exposure to T. gondii infection is present among residents of Tanga district in Tanzania and strengthen further on previous findings that consumption of raw or undercooked meat and keeping pets especially cats presents more of the risk factors than occupational groups. It also emphasizes on the necessity to create awareness of this disease, and advocate protection of risky groups from exposure to infected meat and contaminated environment.

Human brucellosis: seroprevalence and risk factors related to high risk occupational groups in Tanga Municipality, Tanzania.

The objective of this study was to describe the prevalence of brucellosis in various occupations in Tanga, Tanzania. During the year 2004, serum samples were collected from volunteers in various occupations and screened for brucella antibodies using Rose Bengal Plate Agglutination Test. Information on occupation, kind of work and contacts with livestock was collected and age and sex were recorded. The overall sero prevalence of antibodies to Brucella abortus was 5.52%. One variable in a multivariate regression model was significantly associated with seropositivity to B. abortus: abattoir workers. The prevalence of antibody was significantly higher (P < 0.05) among personnel employed in high-risk jobs such as cutting animal throats and cleaning slaughtered animals parts. None of the other factors investigated was associated with seropositivity to B. abortus. This study documents the serological evidence of B. abortus infection for the first time in abattoir workers in Tanzania.

Post-partum reproductive performance of crossbred dairy cattle on smallholder farms in sub-humid coastal Tanzania.

The objective of this study was to monitor the reproductive performance of dairy cows in smallholder farms under the Tanga Dairy Development Project (TDDP). The findings can be used to improve reproductive efficiency. Dates of oestrus, artificial insemination (AI) or service by bull and calving were recorded, and pregnancy was diagnosed by rectal palpation. Daily milk yields, monthly body condition score (BCS) measured on the scale of 1-9, feed availability, calf rearing, and diseases were also recorded. Milk progesterone (P4) concentration was measured by radioimmunoassay (RIA) in 1327 sequential samples collected between day 15 and 120 in 46 post-partum Zebu x Friesian crossbred dairy cows. The mean interval from calving to first P4 rise above 2 nmol/L (cyclicity) was 66.1 +/- 6.8 days. Resumption of ovarian activity postpartum was early (< 60 days) in 45%, and late (> 60 days) in 55% of the cows. In about 45% of the cows the first post-partum ovarian cycles were short (< 14 days) and had low P4 concentrations. Oestrus was missed once or several times in 34.7% of the cows, most likely indicating poor oestrus detection, silent oestrus, or farmers deliberately not taking or reporting their cows for insemination. The mean interval to conception was within 130 days postpartum. Average daily milk production was 5.7 +/- 2.2 L and the mean BCS Was 3.1 +/- 1.3. Both milk production and BCS had no clear influence on the measured reproduction parameters. Clinical uterine involution was complete within 29 +/- 2.6 days of calving in the majority of cows. Progesterone profiles and rectal palpation revealed various causes of infertility, which included anoestrus, silent oestrus, irregular oestrous cycles, and infection of the uterus. The major causes of animal culling, death, slaughter or sales include tick-borne diseases and trypanosomiasis, which have high prevalences in the area, infertility, low productivity and old age. Greater attention should be focused on reproduction and its interaction with nutrition and disease control.