Solón Alberto Orlando

Dozens of RT-qPCR kits are available in the market for SARS-CoV-2 diagnosis, some of them with Emergency Use Authorization (EUA) by the Food and Drug Administration (FDA) or at least by a responsible agency of their country of origin, but many of them lack proper evaluation studies because of COVID-19 pandemic emergency. We evaluated the clinical performance of two commercially available kits in South America, the 2019-nCoV kit (Da An Gene, Guangzhou, China) and GenomeCoV19 kit (ABM, Richmond, Canada), for RT-qPCR SARS-CoV-2 diagnosis using the FDA EUA 2019-nCoV CDC kit (IDT, Coralville, IA) as gold standard. We found striking differences among clinical performance and analytical sensitivity in both kits; whereas the 2019-nCoV kit (Da An Gene) has a limit of detection of 2,000 copies/mL and 100% of sensitivity, the GenomeCoV19 kit (ABM) has a poor sensitivity of 75% and a limit of detection estimated to be over 8.000 copies/mL. The GenomeCoV19 kit (ABM) lacks clinical use authorization in Canada; however, the 2019-nCoV kit (Da An Gene) is authorized by the Chinese CDC. Our results support that only SARS-CoV-2 diagnosis kits with clinical use authorization from their country of origin should be exported to developing countries lacking proper evaluation agencies to avoid a deep impact of the COVID-19 pandemic due to unreliable diagnosis.

In recent years, there has been an increasing risk of hematophagous bat attacks in Latin America, where livestock production is a basic source of food for local populations. In Ecuador, livestock represented an important part of agricultural output. Some cases of cattle bitten by bats in the province of Santa Elena have been reported; however, no previous studies have been conducted to determine the magnitude of the attacks and the associated risk factors. In this research, a cross-sectional descriptive study was performed recording attacks of hematophagous bats (Desmodus rotundus) through visual inspection of livestock and the capture of specimens by mist nets. Generally, the prevalence of D. rotundus attacks on farms was 69%, whereas attacks on bovine had 24% of prevalence. From the captured specimens, 93% were identified as D. rotundus and within the 30% of the captured D. rotundus, no infections for rabies virus were diagnosed. The univariable analysis used for estimating the risk factors associated with bat attacks showed that corrals away from populated centers present the highest risk (odds ratio [OR] = 19.864; p = 0.0004), followed by tree density >30 per hectare (OR = 16.313; p < 0.0001) and predatory birds of bats (OR = 15.375; p < 0.0001); a binary logistic regression model showed “corrals away from populated centers” (OR = 23.47; p = 0.006) as the main risk factor. Linear regression analysis showed good correlation between the number of bovines attacked and the number of bites (R² = 0.977; p < 0.0001) suggesting some feeding patterns of D. rotundus. This study could be used as a starting point for understanding the feeding habits of D. rotundus and factors governing their attacks in coastal regions of Ecuador, and potential occurrences of rabies infections. With this knowledge, surveillance and control programs can be supported to improve rabies transmission monitoring.