Turkiye Klinikleri Journal of Medical Sciences

.: ORIGINAL RESEARCH
Capture-Recapture Methods in Surveillance of Fake Drug Syndicates in Nigeria: Decriptive Research
Nijerya'da Sahte İlaç Şebekelerinin İzlenmesinde Yakala-Tekrar Yakala Yöntemleri: Tanımlayıcı Araştırma
Ugochukwu A. OSISIOGUa , Theresa Ebele EFORa , Chinwuba Emmanuel EMEKAa
aDepartment of Industrial Mathematics and Applied Statistics, Ebonyi State University, Abakaliki, Nigeria
Turkiye Klinikleri J Med Sci. 2024;44(4):158-66
doi: 10.5336/medsci.2024-102797
Article Language: EN
Full Text
ABSTRACT
 Objective: National Agency for Food and Drug Administration and Control (NAFDAC)-agency responsible for checkmating illicit and counterfeit drugs in Nigeria has raised alarm over the years the menace caused by fake and adulterated drugs in Nigeria. The Agency reported that fake drugs have claimed the life of many Nigerians especially children and old people. We believe this is only part of the story, because the syndicates of these drugs are also integral part of the problem. Yet no effort was made to examine the population size of these syndicates. This gap in the literature is what informed our study. Material and Methods: In this study, we estimate the population size of fake drug syndicates (FDS) by capture-recapture methods. Information on FDSs was obtained from the NAFDAC newsmagazines. Four candidate estimators namely; Maximum Likelihood, Turing, Chao and Zelterman of zero-truncated Poisson models were used. Results: The weighted estimator constructed estimated the population size of FDSs to be 11,469. Since 2,038 syndicates were arrested January to December, 2022, suggests that only 18% of the FDSs have been observed with 95% confidence interval of (9564-13374), leaving 82% of them still in the distribution chain. The study also shows that among the offense committed falsification of genuine drugs was the most rampant, followed by selling of expired drugs. Conclusion: Aside the population size of FDSs, this study will also form the basis for resource allocation to NAFDAC, because it may not be possible to fight war against fake drugs without investing in novel technologies.

Keywords: Poisson distribution; likelihood functions; counterfeit drugs; treatment failure; death
ÖZET
 Amaç: Nijerya'da yasa dışı ve sahte ilaçlarla mücadeleden sorumlu olan Ulusal Gıda ve İlaç İdaresi ve Kontrol Ajansı [National Agency for Food and Drug Administration and Control (NAFDAC)], yıllardır sahte ve bozulmuş ilaçların neden olduğu tehdide karşı alarm verdi. Ajans, sahte ilaçların özellikle çocuklar ve yaşlılar başta olmak üzere birçok Nijeryalı'nın hayatına mal olduğunu bildirmiştir. Ancak bunun hikâyenin sadece bir kısmını oluşturduğuna inanıyoruz; sahte ilaç örgütleri (SİÖ) de problemin ayrılmaz bir parçasıdır. Buna rağmen bu örgütlerin popülasyon büyüklüğünü incelemek için hiçbir çalışma yapılmamıştır. Literatürdeki bu boşluk, çalışmamızın temelini oluşturmuştur. Gereç ve Yöntemler: Bu çalışmada, SİÖ'lerin popülasyon büyüklüğü, yakala-tekrar yakala yöntemleri ile tahmin edilmiştir. SİÖ hakkında bilgiler, NAFDAC haber dergilerinden elde edilmiştir. Çalışmada, sıfır-kesikli Poisson modellerinin Maksimum Olabilirlik, Turing, Chao ve Zelterman olmak üzere dört aday tahmin edicisi kullanılmıştır. Bulgular: Ağırlıklı tahmin edici, SİÖ'nün popülasyon büyüklüğünü 11.469 olarak tahmin etmiştir. Ocak-Aralık 2022 arasında 2.038 örgütün yakalanmış olması, %95 güven aralığında (9.564- 13.374) SİÖ'lerin yalnızca %18'inin gözlemlendiğini ve kalan %82'sinin hâlâ dağıtım zincirinde yer aldığını göstermektedir. Çalışmada ayrıca, tespit edilen suçlar arasında en yaygın olanının orijinal ilaçlarda sahteciliğin olduğu ve bunu son kullanma tarihi geçmiş ilaçların satışının izlediği belirlenmiştir. Sonuç: SİÖ'lerin popülasyon büyüklüğünün yanı sıra bu çalışma NAFDAC'a kaynak tahsisi için de bir temel oluşturacaktır; çünkü sahte ilaçlarla mücadelede yeni teknolojilere yatırım yapılmadan bu savaşın kazanılması mümkün olmayabilir.

Anahtar Kelimeler: Poisson dağılımı; olabilirlik fonksiyonları; sahte ilaçlar; tedavi başarısızlığı; ölüm
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30.03.2014

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