First record of Dioctophyme renale (Goeze, 1782) in the pampas fox (Lycalopex gymnocercus, Fischer, 1814) (Carnivora: Canidae).

Dioctophyme renale (Goeze 1782) has not previously been reported in the pampas fox (Lycalopex gymnocercus) (Fisher 1814), the most abundant canid of southern South America. A wild adult pampas fox female was found dead due to unknown causes in Santa Fe province, Argentina. Post-mortem examination revealed three red worms measuring 10, 11 and 15 cm long, each with an approximate width of 5 mm. All of them were found free in the abdominal cavity. The worms were all male and were identified through morphological examination and molecular analysis as D. renale. No worm was found in the kidneys. This study reports the first case of dioctophymatosis in the pampas fox in Argentina, increasing the range of wild aberrant host species infected by the giant kidney worm in the Neotropical region.

Preceding anti-spike IgG levels predicted risk and severity of COVID-19 during the Omicron-dominant wave in Santa Fe city, Argentina

The SARS-CoV-2 Omicron variant has increased infectivity and immune escape compared with previous variants, and caused massive COVID-19 waves globally. Despite a vast majority ([~]90%) of the population of Santa Fe city, Argentina, had been vaccinated and/or had been infected by SARS-CoV-2 by the arrival of Omicron, the epidemic wave that followed was by far the largest one experienced in the city. A serosurvey conducted prior to the arrival of Omicron allowed to assess the acquired humoural defences preceding the wave and to evaluate associations with infection risk and severity during the wave. A very large proportion of the 1455 sampled individuals had immunological memory against COVID-19 at the arrival of Omicron (almost 90%), and about half (48.9%) had high anti-Spike IgG levels (>200 UI/ml). The antibody titres were strongly associated with the number of vaccine shots and the vaccine platform received, and also depended markedly on prior COVID-19 diagnosis and the days elapsed since last antigen exposure (vaccine shot or natural infection). Following-up 514 participants provided real-world data linking antibody levels with protection against COVID-19 during a period of high risk of exposure to an immune-escaping highly transmissible variant. Pre-wave antibody titres were strongly associated with COVID-19 incidence and severity of symptoms during the wave. Also, receiving a vaccine shot during the follow-up period reduced the COVID-19 risk drastically (15-fold). These results highlight the importance of maintaining high defences through vaccination anticipating or during a period of high risk of exposure to immune-escaping variants.