Clinical manifestations of SARS-CoV-2 infection include more frequently fever and cough, but complications (such as pneumonia, respiratory distress syndrome, and multiorgan failure) can occur in persons with additional comorbidities. Liver dysfunction is one of the most striking affections among patients suggesting that SARS-CoV-2 may represent a new king of liver aggressor. However, the molecular process underlying this phenomenon is still unclear. In this work, we overview the most recent findings between the molecular biology of the virus, pathogenic mechanisms, and its relationship to liver disease observed in patients.

Chikungunya fever is an arthropod-borne infection caused by Chikungunya virus (CHIKV). Even though clinical features of Chikungunya fever in the Mexican population have been described before, there is no detailed information. The aim of this study was to perform a full description of the clinical features in confirmed Chikungunya-infected patients and describe the molecular epidemiology of CHIKV. We evaluated febrile patients who sought medical assistance in Tapachula, Chiapas, Mexico, from June through July 2015. Infection was confirmed with molecular and serological methods. Viruses were isolated and the E1 gene was sequenced. Phylogeny reconstruction was inferred using maximum-likelihood and maximum clade credibility approaches. We studied 52 patients with confirmed CHIKV infection. They were more likely to have wrist, metacarpophalangeal, and knee arthralgia. Two combinations of clinical features were obtained to differentiate between Chikungunya fever and acute undifferentiated febrile illness. We obtained 10 CHIKV E1 sequences that grouped with the Asian lineage. Seven strains diverged from the formerly reported. Patients infected with the divergent CHIKV strains showed a broader spectrum of clinical manifestations. We defined the complete clinical features of Chikungunya fever in patients from Southeastern Mexico. Our results demonstrate co-circulation of different CHIKV strains in the state of Chiapas.

No abstract

No abstract

SummaryBackgroundThe progression and distribution of SARS-CoV-2 is unknown because typically only symptomatic individuals are diagnosed.AimWe evaluated the seroprevalence of anti-SARS-CoV-2 in blood donors in Nuevo Leon, Mexico as a strategy for asymptomatic case detection of COVID-19 and epidemic progression.Methods/MaterialsWe tested 1968 blood donors that attended two regional donation centers in Northeast Mexico from January 1st to August 30, 2020, to identify anti-SARS-CoV-2 IgG by chemiluminescent immunoassay. Additionally, routine tests for donors including Brucella, Chagas, HCV, VDRL, HIV-1, and HBsAg identification were performed.ResultsWe found 77 donors reactive for anti-SARS-CoV-2 IgG (seroprevalence 3.99%) and none of them had reported recent COVID-19 symptoms. Donors aged 18 to 49 years (89.5%) were more likely to be seropositive compared to those aged 50 years or older (10.5%) (P<0.001). Prevalence of antibodies increased each epidemiological (EPI) week, parallel to the report of confirmed cases by RT-PCR, identifying the highest prevalence between EPI week 33 and 35 (10.2% to 19%). The metropolitan area of Monterrey recorded the highest number of cases. Routine tests showed that the prevalence of anti-Brucella was 0.13%, anti-HCV 0.5%, anti-HIV-1-2 0.14%, HBsAg 0.16%, Chagas 0.48% and syphilis 1.06%.ConclusionsThere is a growing trend of seroprevalence over time, parallel to the constantly increasing epidemic curve in our region and it was higher under 49 years of age associated with asymptomatic infection in donors from the Nuevo Leon area. Detection of anti-SARS-CoV-2 in blood donors is a potential tool for tracking the progression and identifying population exposure during the SARS-CoV-2 outbreak.

Mexico took swift action and has strictly followed mitigation measures to prevent the spread of coronavirus disease, COVID-19. In this study we compared influenza activity indicators in our country after the implementation of public health measures for COVID-19. We compared indicators of influenza activity in 2020 before and after public health measures were taken to reduce COVID-19 with the corresponding indicators from three preceding years and the immediate one, and the potential decrease in seasonal influenza cases/deaths. Nationwide surveillance data revealed a drastic decline in influenza diagnosis in outpatient clinics and public hospitals, influenza positivity rates of clinical specimens, and confirmed severe cases during the following 10 weeks of 2020 as lockdown activities and control measures were established compared with the same period of 2019. Our results suggest that the measures taken for COVID-19 were effective in reducing the spread of other viral respiratory diseases as influenza in our country.

No abstract

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes Chikungunya fever. CHIKV entered Mexico through the state of Chiapas in October 2014. To fully understand the Chikungunya fever outbreak that occurred in southern Chiapas during 2015, we evaluated 22 PCR-confirmed CHIKV-positive patients, identified CHIKV genetic variability, reconstructed viral dispersal, and assessed possible viral mutations. Viruses were isolated and E2, 6K, and E1 genes were sequenced. We applied phylogenetic and phylogeographic approaches, modeled mutations, and estimated selective pressure. Different CHIKV strains circulated in Chiapas during summer 2015. Three isolates grouped themselves in a well-supported clade. Estimates show that the outbreak started in Ciudad Hidalgo and posteriorly dispersed towards Tapachula and neighboring municipalities. We found six non-synonymous mutations in our isolates. Two mutations occurred in one isolate and the remaining mutations occurred in single isolates. Mutations E2 T116I and E2 K221R changed the protein surface in contact with the host cell receptors. We could not find positive selected sites in our CHIKV sequences from southern Chiapas. This is the first viral phylogeographic reconstruction in Mexico characterizing the CHIKV outbreak in southern Chiapas.