ESTIMASI VALUE AT RISK DAN EXPECTED TAIL LOSS DENGAN GENERALIZED ASYMMETRIC STUDENT-T DISTRIBUTION UNTUK RETURN ASET TUNGGAL

Iis Irawanti, drh. Heru Susetya, MP., Ph.D

2012 | Tesis | S2 Sain Veteriner

Rabies endemis di Sumatera Barat dan pemberantasannya diprioritaskan pemerintah. Cakupan proteksi 70% dari populasi menjadi target pemberantasan. Penelitian ini bertujuan untuk mengetahui keadan rantai dingin vaksin di titik pelayanan vaksinasi rabies di Sumatera Barat dan faktor-faktor yang berasosiasi dengan titer antibodi protektif anjing pasca-vaksinasi rabies, termasuk rantai dingin vaksin. Suatu kajian observasional dengan rancangan kasus-kontrol telah dilaksanakan dengan menggunakan data hasil pemeriksaan serologi anjing pasca-vaksinasi rabies di Sumatera Barat yang dilakukan BPPV Regional II pada tahun 2010- 2011. Sampel terdiri dari 90 kasus (titer ≥ 0,5 IU per ml) dan 90 kontrol (< 0,5 IU per ml). Informasi mengenai faktor-faktor yang berpotensi mempengaruhi titer protektif dijaring melalui wawancara dan observasi. Asosiasi antara titer (protektif/tidak protektif) dengan faktor-faktor yang berpotensi mempengaruhi dianalisis dengan chi-square dan regresi logistik. Semua analisis statistik menggunakan tingkat kebermaknaan (p) sebesar 0,05. Hasil penilaian rantai dingin sumber vaksin menunjukkan bahwa masih banyak petugas yang tidak mengetahui dan melakukan penyimpanan dan transportasi sesuai prosedur rantai dingin dan beberapa sarana rantai dingin masih belum memadai. Faktor-faktor yang signifikan berasosiasi dengan uji chi-square adalah pendapatan pemilik perbulan, jumlah vaksinasi, program vaksinasi (massal dan door to door), interval waktu vaksinasi dengan pengambilan serum (<6 bulan, 6- 12 bulan dan >12 bulan), rantai dingin vaksin dan lokasi (Dharmasraya, Bukittinggi, Tanah Datar dan Padang Pariaman. Model yang didapat dengan analisis regresi logistik menunjukkan bahwa jumlah vaksinasi lebih dari satu kali, interval waktu vaksinasi kurang dari enam bulan, Dharmasraya, dan Padang Pariaman meningkatkan probabilitas titer protektif sedangkan program vaksinasi massal menurunkannya. Model tersebut memiliki sensitivitas 56,67% dan spesifisitas 86,67%.

Rabies is endemic in West Sumatra and its eradication becomes the government priority. Protective vaccination of 70% of the population is necessary. The objectives of this study were to determine the state of the vaccine cold chain at service points of rabies vaccination in West Sumatra and to investigate factors, including the vaccine cold chain, associated with the protective of antibody titre (≥ 0.5 IU/mL) of dogs. An observational study with case-control design, using data from the results of dog post-vaccination serological test in West Sumatra carried out by BPPV Regional II in 2010-2011 was conducted. Sample consisted of 90 cases (titre ≥0.5 IU per mL) and 90 controls (titre < 0.5 IU per mL). Potential risk factors were collected by means of interview and observation. The vaccine cold chain was assessed by observation and interview to the storage and vaccine carrier officers of the source of vaccine used. Associations between titre (protective or not protective) and potential risk factors were analysed using chi-square and logistic regression. All statistical analysis used p level 0f 0.05. The result of cold chain assessment showed that there were many officers who do not understand and do not properly storage procedures. Some of the cold chain facilities and equipments were still inadequate. Factors significantly associated with the protective titre by chi-square test were the owner income, number of vaccination, vaccination programs (mass and door to door), intervals between the last vaccination and serum collection (<6, 6-12 and >12 months), vaccines cold chain, and locations (Dharmasraya, Bukittinggi, Tanah Datar dan Padang Pariaman. The model obtained by logistic regression analysis showed that more than one time vaccination, interval less than six months, Dharmasraya and Padang Pariaman increase the probability of protective titer while the mass vaccination program decrease it. The sensitivity and specificity of that model were 56.67% and 86.67%, respectively.

Kata Kunci : rabies, vaksinasi, titer protektif, anjing, Sumatera Barat.