Abstract Through evolutionary time, seal lice have developed morphological, behavioral, and ecological adaptations to cope with the amphibious lifestyle of their hosts in a co-evolutionary process. Consequently, the dynamics of lice populations are determined by seals behavior. We aim to study the effects of host sex, age class, year, and sampling location, on the prevalence and mean abundance of Antarctophthirus carlinii, on Weddell seals (WS) Leptonychotes wedelli. The study was conducted at two sites in the Antarctic Peninsula, namely, Marambio/Seymour Island (MI) and the Danco Coast (DC). We collected lice from 71 WS: 33 from MI, during the reproductive season, and 38 from DC, during the molting season, between 2014 and 2017. According to our analyses, host age class and sex were the variables that affected prevalence levels of lice on WS. Whereas, age class, year, site, and sex affected lice mean abundance. Juveniles presented higher prevalence and mean abundance than adults, possibly acting as reservoirs for lice as they move through different colonies until they reach reproductive age. Concurrently, seals during molting season were more infested. Unlike nursing, during the molting season seals spend much time ashore forming mixed groups that favor both egg development and lice transmission.

Resumen Introducción: El objetivo principal fue comparar la actividad clínico-quirúrgica de nuestro Servicio de Ortopedia y Traumatología antes de la instauración del plan de contingencia frente a la pandemia de la COVID-19 y durante este, un aspecto relevante para establecer antecedentes que permitan guiar nuestro desempeño ante la segunda ola de casos y futuras contingencias semejantes. Materiales y Métodos: Estudio analítico observacional longitudinal ambispectivo de los pacientes atendidos en el Servicio de Ortopedia y Traumatología de un hospital del sistema público de la Ciudad Autónoma de Buenos Aires, durante el plan de contingencia frente a la pandemia de la COVID-19. Como variable de resultado primaria se valoró el número total de cirugías realizadas durante el período de estudio. Resultados: La pandemia se asoció con menos cirugías totales (p = 0,002), de Guardia (p = 0,000) y de Planta (p = 0,002). Las cirugías totales se redujeron un 81,5%. Las cirugías de urgencia representaron el 97%, diferencia significativa con el período fuera de la pandemia (p = 0,080). Además, el promedio de cirugías por día quirúrgico disponible fue significativamente menor (p = 0,000). Conclusiones: Creemos que la atención de la enfermedad ortopédica y el trauma musculoesquelético, adaptada a las obligaciones indicadas por el plan nacional y regional de contingencia frente a la pandemia, fue notoriamente menor que nuestro desempeño habitual. Si bien respondimos adecuadamente a las urgencias de nuestra especialidad queda pendiente la posibilidad de estratificar y considerar tipos de pacientes con cuadros pasibles de ser tratados, en forma gradual, durante la pandemia.

Abstract Introduction: Our aim was to compare our activity in the Orthopedics and Traumatology service during the first wave of the COVID-19 pandemic. Materials and Methods: Ambispective longitudinal observational analytical study of patients treated in the Orthopedics and Traumatology Service of a public health hospital of Buenos Aires during the first wave of the COVID-19 pandemic. The primary outcome variable was the total number of surgeries performed during the study period. Results: The pandemic was associated with fewer total surgeries (p = 0.002), emergency department surgeries (p = 0.000) and elective surgeries (p = 0.002). Total surgeries were reduced by 81.5%. Emergency surgeries accounted for 97%, a significant difference with the non-pandemic period (p = 0.080). Additionally, the average number of surgeries per available surgical day was significantly lower (p = 0.000). Conclusions: We believe that, under the regulations indicated by the national and regional pandemic contingency plan, the care of orthopedic pathology and musculoskeletal trauma was notoriously lower than our usual performance. Although we responded adequately to the emergencies of our specialty, the possibility of stratifying and considering types of patients with conditions that could be treated gradually during the pandemic remains pending.