Reinfecciones por SARS-CoV-2 durante la segunda ola pandémica en Iquitos, Perú / SARS-CoV-2 reinfections during the second pandemic wave in Iquitos, Peru

Señor editor: La infección por SARS-CoV-2 ha ocasionado gran impacto en todo el mundo estimándose en más de 439 millones de casos y más de 5,9 millones de muertes. El Perú ha sido uno de los países en donde la mortalidad de su población ha descrito cifras muy elevadas llegando hasta una tasa de letalidad de 9.14%. Iquitos ha sido una de las ciudades más afectadas desde el inicio de la pandemia en el Perú, en donde se describió una seroprevalencia COVID-19 de 70% una de las más altas reportadas después de la primera ola pandémica de COVID-19. Es de esperar que esta seroprevalencia haya aumentado luego de la segunda ola. La duración de la inmunidad frente al SARS-CoV-2 ya sea por infección previa o por vacunación efectiva continúa siendo una de las interrogantes más importantes, en ese contexto, reportamos 4 casos de reinfecciones confirmadas en Iquitos Perú.

Dear Editor: SARS-CoV-2 infection has caused great impact worldwide, estimated at more than 439 million cases and more than 5.9 million deaths. Peru has been one of the countries where the mortality of its population has described very high figures reaching a case fatality rate of 9.14%. Iquitos has been one of the most affected cities since the beginning of the pandemic in Peru, where a COVID-19 seroprevalence of 70% was described, one of the highest reported after the first COVID-19 pandemic wave. It is to be expected that this seroprevalence has increased after the second wave. The duration of immunity against SARS-CoV-2 either by previous infection or by effective vaccination continues to be one of the most important questions, in that context, we report 4 cases of confirm reinfections in Iquitos Peru.

Diversity and host assemblage of avian haemosporidians in different terrestrial ecoregions of Peru.

Characterizing the diversity and structure of host-parasite communities is crucial to understanding their eco-evolutionary dynamics. Malaria and related haemosporidian parasites are responsible for fitness loss and mortality in bird species worldwide. However, despite exhibiting the greatest ornithological biodiversity, avian haemosporidians from Neotropical regions are quite unexplored. Here, we analyze the genetic diversity of bird haemosporidian parasites (Plasmodium and Haemoproteus) in 1,336 individuals belonging to 206 bird species to explore for differences in diversity of parasite lineages and bird species across 5 well-differentiated Peruvian ecoregions. We detected 70 different haemosporidian lineages infecting 74 bird species. We showed that 25 out of the 70 haplotypes had not been previously recorded. Moreover, we also identified 81 new host-parasite interactions representing new host records for these haemosporidian parasites. Our outcomes revealed that the effective diversity (as well as the richness, abundance, and Shannon-Weaver index) for both birds and parasite lineages was higher in Amazon basin ecoregions. Furthermore, we also showed that ecoregions with greater diversity of bird species also had high parasite richness, hence suggesting that host community is crucial in explaining parasite richness. Generalist parasites were found in ecoregions with lower bird diversity, implying that the abundance and richness of hosts may shape the exploitation strategy followed by haemosporidian parasites. These outcomes reveal that Neotropical region is a major reservoir of unidentified haemosporidian lineages. Further studies analyzing host distribution and specificity of these parasites in the tropics will provide important knowledge about phylogenetic relationships, phylogeography, and patterns of evolution and distribution of haemosporidian parasites.

Dual RNA-seq identifies human mucosal immunity protein Mucin-13 as a hallmark of Plasmodium exoerythrocytic infection.

The exoerythrocytic stage of Plasmodium infection is a critical window for prophylactic intervention. Using genome-wide dual RNA sequencing of flow-sorted infected and uninfected hepatoma cells we show that the human mucosal immunity gene, mucin-13 (MUC13), is strongly upregulated during Plasmodium exoerythrocytic hepatic-stage infection. We confirm MUC13 transcript increases in hepatoma cell lines and primary hepatocytes. In immunofluorescence assays, host MUC13 protein expression distinguishes infected cells from adjacent uninfected cells and shows similar colocalization with parasite biomarkers such as UIS4 and HSP70. We further show that localization patterns are species independent, marking both P. berghei and P. vivax infected cells, and that MUC13 can be used to identify compounds that inhibit parasite replication in hepatocytes. This data provides insights into host-parasite interactions in Plasmodium infection, and demonstrates that a component of host mucosal immunity is reprogrammed during the progression of infection.