Persistence of SARS-CoV-2–Specific IgG in Children 6 Months After Infection,Australia

The duration of the humoral immune response in children infected with severe acute respiratory syndrome coronavirus 2 is unknown. We detected specific IgG 6 months after infection in children who were asymptomatic or had mild symptoms of coronavirus disease. These findings will inform vaccination strategies and other prevention measures.     

SARS-CoV-2–Specific Antibodies in Domestic Cats during First COVID-19 Wave,Europe

We conducted a severe acute respiratory syndrome coronavirus 2 antibody seroprevalence study among >2,000 domestic cats from 4 countries during the first coronavirus disease wave in Europe. We found 4.4% seroprevalence using a virus neutralization test and 4.3% using a receptor-binding domain ELISA, demonstrating probable human-to-cat transmission.     

COVID-19–Associated Mold Infection in Critically Ill Patients,Chile

Patients with severe coronavirus disease (COVID-19) may have COVID-19–associated invasive mold infection (CAIMI) develop. We report 16 cases of CAIMI among 146 nonimmunocompromised patients with severe COVID-19 at an academic hospital in Santiago, Chile. These rates correspond to a CAIMI incidence of 11%; the mortality rate for these patients was 31.2%.     

Sensitive Detection of SARS-CoV-2–Specific Antibodies in Dried Blood Spot Samples

Dried blood spot (DBS) samples can be used for the detection of severe acute respiratory syndrome coronavirus 2 spike antibodies. DBS sampling is comparable to matched serum samples with a relative 98.1% sensitivity and 100% specificity. Thus, DBS sampling offers an alternative for population-wide serologic testing in the coronavirus pandemic.     

Increased COVID-19 Severity among Pregnant Patients Infected with SARS-CoV-2 Delta Variant,France

We conducted a retrospective study of pregnant persons hospitalized for severe acute respiratory syndrome coronavirus 2 infection in France. Delta variant infection had a relative risk of 14.33 for intensive care unit admission and 9.56 for high supplemental oxygen support. The Delta variant might cause more severe illness during pregnancy.     

COVID-19–Associated Fusobacterium nucleatum Bacteremia,Belgium

We report 4 cases of Fusobacterium nucleatum bacteremia associated with coronavirus disease (COVID-19). Three cases occurred concomitantly with COVID-19 diagnosis; 1 occurred on day 15 of intensive care. None of the patients had known risk factors for F. nucleatum bacteremia. F. nucleatum infection could represent a possible complication of COVID-19.     

TIGIT Monoallelic Nonsense Variant in Patient with Severe COVID-19 Infection,Thailand

A heterozygous nonsense variant in the TIGIT gene was identified in a patient in Thailand who had severe COVID-19, resulting in lower TIGIT expression in T cells. The patient’s T cells produced higher levels of cytokines upon stimulation. This mutation causes less-controlled immune responses, which might contribute to COVID-19 severity.     

Epidemiology of COVID-19 after Emergence of SARS-CoV-2 Gamma Variant,Brazilian Amazon, 2020–2021

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Gamma variant has been hypothesized to cause more severe illness than previous variants, especially in children. Successive SARS-CoV-2 IgG serosurveys in the Brazilian Amazon showed that age-specific attack rates and proportions of symptomatic SARS-CoV-2 infections were similar before and after Gamma variant emergence.     

Prevalence and Time Trend of SARS-CoV-2 Infection in Puducherry,India, August–October 2020

We conducted 3 population-based cross-sectional surveys, at 1-month intervals, to estimate the prevalence and time-trend of severe acute respiratory syndrome coronavirus 2 infection in Puducherry, India. Seropositivity rate increased from 4.9% to 34.5% over 2 months and was 20-fold higher than the number of diagnosed cases of infection.     

Protective Immunity and Persistent Lung Sequelae in Domestic Cats after SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 readily transmits between domestic cats. We found that domestic cats that recover from an initial infection might be protected from reinfection. However, we found long-term persistence of inflammation and other lung lesions after infection, despite a lack of clinical symptoms and limited viral replication in the lungs.     

Cross-Sectional Serosurvey of Companion Animals Housed with SARS-CoV-2–Infected Owners,Italy

We conducted a serologic survey among dogs and cats in Italy to detect antibodies against severe acute respiratory syndrome virus 2 (SARS-CoV-2). We found that SARS-CoV-2 seroprevalence was higher among cats (16.2%) than dogs (2.3%). In addition, seroprevalence was higher among animals living in close contact with SARS-CoV-2–positive owners.     

SARS-CoV-2 Variants,South Sudan,January–March 2021

As the coronavirus pandemic continues, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequence data are required to inform vaccine efforts. We provide SARS-CoV-2 sequence data from South Sudan and document the dominance of SARS-CoV-2 lineage B.1.525 (Eta variant) during the country''s second wave of infection.     

Estimating Transmission Parameters for COVID-19 Clusters by Using Symptom Onset Data,Singapore, January–April 2020

We estimated the generation interval distribution for coronavirus disease on the basis of serial intervals of observed infector–infectee pairs from established clusters in Singapore. The short mean generation interval and consequent high prevalence of presymptomatic transmission requires public health control measures to be responsive to these characteristics of the epidemic.     

Multisystem Inflammatory Syndrome after SARS-CoV-2 Infection and COVID-19 Vaccination

We report 3 patients in California, USA, who experienced multisystem inflammatory syndrome (MIS) after immunization and severe acute respiratory syndrome coronavirus 2 infection. During the same period, 3 adults who were not vaccinated had MIS develop at a time when ≈7% of the adult patient population had received >1 vaccine.     

SARS-CoV-2 IgG Seroprevalence among Blood Donors as a Monitor of the COVID-19 Epidemic,Brazil

During epidemics, data from different sources can provide information on varying aspects of the epidemic process. Serology-based epidemiologic surveys could be used to compose a consistent epidemic scenario. We assessed the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG in serum samples collected from 7,837 blood donors in 7 cities of Brazil during March–December 2020. Based on our results, we propose a modification in a compartmental model that uses reported number of SARS-CoV-2 cases and serology results from blood donors as inputs and delivers estimates of hidden variables, such as daily values of SARS-CoV-2 transmission rates and cumulative incidence rate of reported and unreported SARS-CoV-2 cases. We concluded that the information about cumulative incidence of a disease in a city’s population can be obtained by testing serum samples collected from blood donors. Our proposed method also can be extended to surveillance of other infectious diseases.     

COVID-19–Associated Pulmonary Aspergillosis,March–August 2020

Pneumonia caused by severe acute respiratory syndrome coronavirus 2 emerged in China at the end of 2019. Because of the severe immunomodulation and lymphocyte depletion caused by this virus and the subsequent administration of drugs directed at the immune system, we anticipated that patients might experience fungal superinfection. We collected data from 186 patients who had coronavirus disease–associated pulmonary aspergillosis (CAPA) worldwide during March–August 2020. Overall, 182 patients were admitted to the intensive care unit (ICU), including 180 with acute respiratory distress syndrome and 175 who received mechanical ventilation. CAPA was diagnosed a median of 10 days after coronavirus disease diagnosis. Aspergillus fumigatus was identified in 80.3% of patient cultures, 4 of which were azole-resistant. Most (52.7%) patients received voriconazole. In total, 52.2% of patients died; of the deaths, 33.0% were attributed to CAPA. We found that the cumulative incidence of CAPA in the ICU ranged from 1.0% to 39.1%.     

Experimental Infection of Cattle with SARS-CoV-2

We inoculated 6 cattle with severe acute respiratory syndrome coronavirus 2 and kept them together with 3 uninoculated cattle. We observed viral replication and specific seroreactivity in 2 inoculated animals, despite high levels of preexisting antibody titers against a bovine betacoronavirus. The in-contact animals did not become infected.     

COVID-19–Related Misinformation among Parents of Patients with Pediatric Cancer

We conducted a survey among 735 parents to determine differences in endorsement of misinformation related to the coronavirus disease pandemic between parents of children in cancer treatment and those with children who had no cancer history. Parents of children with cancer were more likely to believe misinformation than parents of children without cancer.     

Introduction of ORF3a-Q57H SARS-CoV-2 Variant Causing Fourth Epidemic Wave of COVID-19, Hong Kong,China

We describe an introduction of clade GH severe acute respiratory syndrome coronavirus 2 causing a fourth wave of coronavirus disease in Hong Kong. The virus has an ORF3a-Q57H mutation, causing truncation of ORF3b. This virus evades induction of cytokine, chemokine, and interferon-stimulated gene expression in primary human respiratory cells.