by using polymerase chain reaction

Cacao swollen shoot virus (CSSV) is an endemic pathogen causing significant economic losses to cacao (Theobroma cacao L.) production in West Africa. There is limited updated report on the occurrence, spread, genetic diversity and species of CSSV and its mealybug vectors, especially in Nigeria. Nigeria is presently lagging behind in the search for resistance to CSSV and its vectors in T. cacao L. The present study aimed to map and screen for the presence of CSSV and its natural vectors - female mealybugs (Pseudococcidae: Hemiptera) in cacao plantations in Nigeria. Symptomatic and asymptomatic cacao leaves and whole female mealybug samples were collected from major cacao-growing areas in Nigeria - Abia, Akwa Ibom, Cross River, Edo, Ondo and Oyo States. A total of 2568 cacao leaves from 1052 cacao trees were screened with polymerase chain reaction (PCR) using an open reading frame 1 (ORF 1) CSSV-specific primer pair. PCR screening of the mealybug species was performed using the cytochrome c oxidase subunit I (COI) gene. A combination of scanning electron microscopy (SEM) and histology for morphological identification and DNA barcoding enabled to characterise the female mealybug species. The results revealed that CSSV and its mealybug vectors are present in the major cacaogrowing areas in Nigeria. Although CSSV and its vectors have been previously reported in Cross River, Ondo and Oyo States, our results present the first documented evidence of CSSV emergence and its mealybug vectors in Abia, Akwa Ibom and Edo States. We also present the first report of Pseudococcus jackbeardsleyi (Gimpel and Miller) mealybug species on cacao in Nigeria. In conclusion, it is pertinent to re-establish coordinated routine survey and monitoring of CSSV and its mealybug vector presence in T. cacao L. in Nigeria.

Neurological complications in COVID-19 - a diagnostic challenge

With the exponential growth of COVID-19 cases, the neurological complications reported during or after the infection became more common. There is limited knowledge regarding the pathophysiological mechanisms that are responsible for these complications. Recent data provides compelling evidence for the neurotropic nature of SARS-CoV-2, based on neurological manifestations reported during the current pandemic, as well as on previous experience with other coronaviruses. We present the case of a patient who developed headaches, motor deficit and dysphasia after respiratory COVID-19. Imaging tests showed heterogeneous central nervous system lesions (multiple subarachnoid hemorrhages and two ischemic strokes). Given the plethora of atypical neurological complications of COVID-19 described in the current literature, establishing a positive diagnosis and deciding on a treatment plan proved to be particularly challenging. We set to discuss some of the possible pathologies, hypothesized to be associated with COVID-19, that could lead to concomitant neurological lesions, similar to those noticed in our patient.