Epidemiological and clinical features of human rabies cases in Bali 2008-2010.

BACKGROUND: Previously thought to be rabies free, Bali experienced an outbreak of animal and human rabies cases in November 2008. We describe the epidemiological and clinical data of human rabies cases occurring in the first two years of the outbreak. METHODS: We analysed the patient records of all rabies cases from the Sanglah General Hospital in Denpasar, and district hospitals in Buleleng and Tabanan. A conventional reverse transcriptase polymerase chain reaction was developed to detect the rabies virus genome in saliva, corneal swabs, and ante- and post-mortem cerebrospinal fluid (CSF). RESULTS: There were 104 human rabies cases in Bali during November 2008-November 2010. Patients' mean age was 36.6 years (range 3-84 years; SD 20.7), most were male (56.7%), and originated from rural districts. Almost all (92%) cases had a history of dog bite. Only 5.8% had their wounds treated and received an anti-rabies vaccine (ARV) after the bite incident. No patients received rabies immunoglobulin (RIG). The estimated time from dog bite to the onset of signs and symptoms was 110.4 days (range 12-720 days; SD 118.2). The mean length of medical care until death was 21.8 hours (range 1-220 hours; SD 32.6). Less than 50% of patients had prodromal symptoms. The most frequent prodromal symptom was pain or paraesthesia at the bite site (37.6%). The two most common central nervous system infection signs were agitation (89.2%) and confusion (83.3%). Signs of autonomic nervous system dysfunction included hydrophobia (93.1%), hypersalivation (88.2%), and dyspnea (74.4%). On admission, 22 of 102 patients (21.6%) showed paralytic manifestations, while the rest (78.4%) showed furious rabies manifestations. The case-fatality rate was 100%. The rabies virus genome was detected in 50 of 101 patients (49.5%) with the highest detection rate from post-mortem CSF samples. CONCLUSIONS: Rabies is a major public health problem in Bali. Human fatalities occur because of a lack of knowledge regarding rabies risk, the poor management of dog bites, and the limited availability of RIG. Increasing public awareness of dog bite management, increasing the availability of ARV and RIG, and implementing an island-wide dog vaccination campaign will help prevent human rabies cases.

An investigation of classical swine fever virus seroprevalence and risk factors in pigs in East Nusa Tenggara, eastern Indonesia.

Classical swine fever virus (CSFV) is a highly infectious disease of pigs. It has had significant impacts on East Nusa Tenggara, eastern Indonesia since its introduction in 1997. In spite of its importance to this region, little is known about its seroprevalence and distribution, and pig-level and farmer-level factors that may have an impact on the serological status of an individual pig. To address this knowledge deficit, a cross-sectional seroprevalence survey was conducted in 2010 involving 2160 pigs and 805 farmers from four islands in the region. Farmer questionnaires and pig record forms were used to collect data about the farmers and pigs surveyed. Blood was collected from each pig to determine its CSFV serological status. Apparent and true prevalence were calculated for each island, district, subdistrict, and village surveyed. CSFV serological status was used as an outcome variable in mixed effects logistic regression analyses. Overall true CSFV seroprevalence was estimated at 17.5% (lower CI 16.0%; upper CI 19.5%). Seroprevalence estimates varied widely across the islands, districts, subdistricts, and villages. Manggarai Barat, a district on the western end of Flores Island, contained pigs that were positive for antibody to CSFV. This result was unexpected, as no clinical cases had been reported in this area. Older pigs and pigs that had been vaccinated for CSFV were more likely to test positive for antibody to CSFV. The final multivariable model accounted for a large amount of variation in the data, however much of this variation was explained by the random effects with less than 2% of the variation explained by pig age and pig CSFV vaccination status. In this study we documented the seroprevalence of CSFV across four islands in East Nusa Tenggara, eastern Indonesia. We also identified risk factors for the presence of antibody to CSFV. Further investigation is needed to understand why clinical CSFV has not been reported on the western end of Flores Island, and to identify additional risk factors that explain CSFV serological status to inform disease control strategies.