Early onset of neurological features differentiates two outbreaks of Lassa fever in Ebonyi state,Nigeria during 2017–2018

Lassa fever (LF) is an acute viral haemorrhagic illness with various non-specific clinical manifestations. Neurological symptoms are rare at the early stage of the disease, but may be seen in late stages, in severely ill patients.The aim of this study was to describe the epidemiological evolution, socio-demographic profiles, clinical characteristics, and outcomes of patients seen during two Lassa fever outbreaks in Ebonyi State, between December 2017 and December 2018.Routinely collected clinical data from all patients admitted to the Virology Centre of the hospital during the period were analysed retrospectively. Out of a total of 83 cases, 70(84.3%) were RT-PCR confirmed while 13 (15.7%) were probable cases. Sixty-nine (83.1%) patients were seen in outbreak 1 of whom 53.6% were urban residents, while 19%, 15%, and 10% were farmers, students and health workers respectively. There were 14 (16.8%) patients, seen in second outbreak with 92.9% rural residents. There were differences in clinical symptoms, signs and laboratory findings between the two outbreaks. The case fatality rates were 29.9% in outbreak 1 and 85.7% for outbreak 2. Neurological features and abnormal laboratory test results were associated with higher mortality rate, seen in outbreak 2. This study revealed significant differences between the two outbreaks. Of particular concern was the higher case fatality during the outbreak 2 which may be from a more virulent strain of the Lassa virus. This has important public health implications and further molecular studies are needed to better define its characteristics.     

Pollen Morphology and Ultrastructure of Laurelia,Laureliopsis and Dryadodaphne (Atherospermataceae [Monimiaceae])

Pollen morphology and ultrastructure of Laurelia novae-zelandiae A. Cunn., L. sempervirens (Ruiz et Pavón) Tulasne, Laureliopsis-philippiana (Looser) Schodde and Dryadodaphne trachyphloia Schodde are described. Laurelia, Laureliopsis and Dryadodaphne have medium-sized, isopolar, globose to globose-ellipsoidal pollen which is either dicolpate (Dryadodaphne, rarely in Laureliopsis) or meridionosulcate, with a median encircling aperture with two wider parts centered at the poles (Laurelia, most pollen of Laureliopsis). Exine is tectate-columellate with an uneven foot layer showing irregular discontinuities. A few tangentially-aligned lamellae show some resemblance to an endexine and in some sections there appears to be an intergradation between these lamellae and small tangentially flattened foot layer parts. The intine consists of an outer channelled zone, with radial (Laurelia sempervirens) or tangential (Dryadodaphne) alignment of channels and an inner intine of homogeneous appearance. The outer intine is thicker in apertural regions and the inner intine is thicker within the apertures of Laureliopsis and Dryadodaphne. The pollen grains of 6 of the 7 genera of Atherospermataceae are compared in tabular form. Although pollen grains show links with other Monimiaceae (sensu lato), it is sufficiently distinct to support the existence of the Atherospermataceae as a separate family. It is acknowledged that, on other grounds, a good case can be made for retention of the group as a subfamily within the Monimiaceae.     

Jones matrix‐based speckle‐decorrelation angiography using polarization‐sensitive optical coherence tomography

We show that polarization‐sensitive optical coherence tomography angiography (PS‐OCTA) based on full Jones matrix assessment of speckle decorrelation offers improved contrast and depth of vessel imaging over conventional OCTA. We determine how best to combine the individual Jones matrix elements and compare the resulting image quality to that of a conventional OCT scanner by co‐locating and imaging the same skin locations with closely matched scanning setups. Vessel projection images from finger and forearm skin demonstrate the benefits of Jones matrix‐based PS‐OCTA. Our study provides a promising starting point and a useful reference for future pre‐clinical and clinical applications of Jones matrix‐based PS‐OCTA.