This article summarizes what is currently known about the 2019 novel coronavirus and offers interim guidance.

BACKGROUND: COVID-19 has disproportionately affected older adults and certain racial and ethnic groups in the US. Data quantifying the disease burden, as well as describing clinical outcomes during hospitalization among these groups, is needed. OBJECTIVE: We aimed to describe interim COVID-19 hospitalization rates and severe clinical outcomes by age group and race and ethnicity among Veterans in a multi-site surveillance network. METHODS: We implemented a multisite COVID-19 surveillance platform in 5 Veterans Affairs Medical Centers (VAMCs: Atlanta, Bronx, Houston, Palo Alto, and Los Angeles), collectively serving >396,000 patients annually. From February 27- July 17 2020, we actively identified SARS-CoV-2 positive inpatient cases through screening of admitted patients and review of laboratory test results. We manually abstracted medical charts for demographics, underlying medical conditions, and clinical outcomes of COVID-19 hospitalized patients. We calculated hospitalization incidence and incidence rate ratios, and relative risk (RR) for invasive mechanical ventilation, intensive care unit (ICU) admission, and death after adjusting for age, race and ethnicity, and underlying medical conditions. RESULTS: We identified 621 laboratory-confirmed hospitalized COVID-19 cases. Median age was 70 years, 66% were aged ≥65 years, and 94% were male. Most COVID-19 diagnoses were among non-Hispanic Blacks (52%), followed by non-Hispanic Whites (25%) and Hispanic or Latinos (18%). Hospitalization rates were highest among Veterans aged ≥85 years, Hispanic or Latino, and non-Hispanic Black (430, 317 and 298 per 100,000, respectively); Veterans aged ≥85 years had a 14-fold increased rate of hospitalization compared with Veterans aged 18-29 years (95% CI: 5.7-34.6), while Hispanic or Latino and Black Veterans had a 4.6 and 4.2-fold increased rate of hospitalization compared with non-Hispanic White Veterans (95% CI: 3.6-5.9), respectively. Overall, 11.6% of patients required invasive mechanical ventilation, 26.6% were admitted to the intensive care unit (ICU), and 16.9% died in hospital. The adjusted RR for invasive mechanical ventilation and ICU admission did not differ by age group or race/ethnicity, but Veterans aged ≥65 had a 4.5-fold increased risk of death while hospitalized with COVID-19 compared with those aged <65 years (95% CI: 2.4-8.6). CONCLUSIONS: COVID-19 surveillance at 5 VAMCs across the US demonstrated higher hospitalization rates and severe outcomes in older Veterans, and higher hospitalization rates in Hispanic or Latino and non-Hispanic Black Veterans compared to non-Hispanic White Veterans. These data highlight the need for targeted prevention and timely treatment for Veterans, with special attention to increasing age, Hispanic or Latino and non-Hispanic Black Veterans.

Coronavirus disease 2019 (COVID-19) is primarily a respiratory illness, although increasing evidence indicates that infection with SARS-CoV-2, the virus that causes COVID-19, can affect multiple organ systems (1). Data that examine all in-hospital complications of COVID-19 and that compare these complications with those associated with other viral respiratory pathogens, such as influenza, are lacking. To assess complications of COVID-19 and influenza, electronic health records (EHRs) from 3,948 hospitalized patients with COVID-19 (March 1-May 31, 2020) and 5,453 hospitalized patients with influenza (October 1, 2018-February 1, 2020) from the national Veterans Health Administration (VHA), the largest integrated health care system in the United States,* were analyzed. Using International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes, complications in patients with laboratory-confirmed COVID-19 were compared with those in patients with influenza. Risk ratios were calculated and adjusted for age, sex, race/ethnicity, and underlying medical conditions; proportions of complications were stratified among patients with COVID-19 by race/ethnicity. Patients with COVID-19 had almost 19 times the risk for acute respiratory distress syndrome (ARDS) than did patients with influenza, (adjusted risk ratio [aRR] = 18.60; 95% confidence interval [CI] = 12.40-28.00), and more than twice the risk for myocarditis (2.56; 1.17-5.59), deep vein thrombosis (2.81; 2.04-3.87), pulmonary embolism (2.10; 1.53-2.89), intracranial hemorrhage (2.85; 1.35-6.03), acute hepatitis/liver failure (3.13; 1.92-5.10), bacteremia (2.46; 1.91-3.18), and pressure ulcers (2.65; 2.14-3.27). The risks for exacerbations of asthma (0.27; 0.16-0.44) and chronic obstructive pulmonary disease (COPD) (0.37; 0.32-0.42) were lower among patients with COVID-19 than among those with influenza. The percentage of COVID-19 patients who died while hospitalized (21.0%) was more than five times that of influenza patients (3.8%), and the duration of hospitalization was almost three times longer for COVID-19 patients. Among patients with COVID-19, the risk for respiratory, neurologic, and renal complications, and sepsis was higher among non-Hispanic Black or African American (Black) patients, patients of other races, and Hispanic or Latino (Hispanic) patients compared with those in non-Hispanic White (White) patients, even after adjusting for age and underlying medical conditions. These findings highlight the higher risk for most complications associated with COVID-19 compared with influenza and might aid clinicians and researchers in recognizing, monitoring, and managing the spectrum of COVID-19 manifestations. The higher risk for certain complications among racial and ethnic minority patients provides further evidence that certain racial and ethnic minority groups are disproportionally affected by COVID-19 and that this disparity is not solely accounted for by age and underlying medical conditions.

Coronavirus disease 2019 (COVID-19), the respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first identified in Wuhan, China and has since become pandemic. In response to the first cases identified in the United States, close contacts of confirmed COVID-19 cases were investigated to enable early identification and isolation of additional cases and to learn more about risk factors for transmission. Close contacts of nine early travel-related cases in the United States were identified and monitored daily for development of symptoms (active monitoring). Selected close contacts (including those with exposures categorized as higher risk) were targeted for collection of additional exposure information and respiratory samples. Respiratory samples were tested for SARS-CoV-2 by real-time reverse transcription polymerase chain reaction at the Centers for Disease Control and Prevention. Four hundred four close contacts were actively monitored in the jurisdictions that managed the travel-related cases. Three hundred thirty-eight of the 404 close contacts provided at least basic exposure information, of whom 159 close contacts had ≥1 set of respiratory samples collected and tested. Across all actively monitored close contacts, two additional symptomatic COVID-19 cases (i.e., secondary cases) were identified; both secondary cases were in spouses of travel-associated case patients. When considering only household members, all of whom had ≥1 respiratory sample tested for SARS-CoV-2, the secondary attack rate (i.e., the number of secondary cases as a proportion of total close contacts) was 13% (95% CI: 4-38%). The results from these contact tracing investigations suggest that household members, especially significant others, of COVID-19 cases are at highest risk of becoming infected. The importance of personal protective equipment for healthcare workers is also underlined. Isolation of persons with COVID-19, in combination with quarantine of exposed close contacts and practice of everyday preventive behaviors, is important to mitigate spread of COVID-19.

INTRODUCTION: Noroviruses are a leading cause of acute gastroenteritis worldwide. An estimated 21 million illnesses in the United States and upwards of 684 million illnesses worldwide are attributed to norovirus infection. There are no licensed vaccines to prevent norovirus, but several candidates are in development. Areas covered: We review recent advances in molecular epidemiology of noroviruses, immunology, and in-vitro cultivation of noroviruses using human intestinal enteroids. We also provide an update on the status of norovirus vaccine candidates. Expert opinion: Molecular epidemiological studies confirm the tremendous genetic diversity of noroviruses, the continuous emergence of new recombinant strains, and the predominance of GII.4 viruses worldwide. Duration of immunity, extent of cross protection between different genotypes, and differences in strain distribution for young children compared with adults remain key knowledge gaps. Recent discoveries regarding which epitopes are targeted by neutralizing antibodies using the novel in vitro culture of human noroviruses in human intestinal enteroids are enhancing our understanding of mechanisms of protection and providing guidance for vaccine development. A future norovirus vaccine has the potential to substantially reduce the burden of illnesses due to this ubiquitous virus.

OBJECTIVE: To estimate the prevalence of microcephaly and central nervous system (CNS) defects during the Zika virus (ZIKV) epidemic in Colombia and proportion attributable to congenital ZIKV infection. STUDY DESIGN: Clinical and laboratory data for cases of microcephaly and/or CNS defects reported to national surveillance between 2015 and 2017 were reviewed and classified by a panel of clinical subject matter experts. Maternal and fetal/infant biologic specimens were tested for congenital infection and chromosomal abnormalities. Infants/fetuses with microcephaly and/or CNS defects (cases) were classified into broad etiologic categories (teratogenic, genetic, multifactorial, and unknown). Cases classified as potentially attributable to congenital ZIKV infection were stratified by strength of evidence for ZIKV etiology (strong, moderate, or limited) using a novel strategy considering birth defects unique or specific to ZIKV or other infections and laboratory evidence. RESULTS: Among 858 reported cases with sufficient information supporting a diagnosis of microcephaly or CNS defects, 503 were classified as potentially attributable to congenital ZIKV infection. Of these, the strength of evidence was considered strong in 124 (24.7%) cases; moderate in 232 (46.1%) cases; and limited in 147 (29.2%). Of the remaining, 355 (41.4%) were attributed to etiologies other than ZIKV infection (syphilis, toxoplasmosis, rubella, cytomegalovirus, herpes 1 and herpes 2 viruses only, n = 32 [3.7%]; genetic, n = 16 [1.9%]; multifactorial, n = 42 [4.9%]; unknown, n = 265 [30.9%]). CONCLUSIONS: Fifty-eight percent of cases of microcephaly and/or CNS defects were potentially attributable to congenital ZIKV infection; however, the strength of evidence varied considerably. This surveillance protocol might serve as a model approach for investigation and etiologic classification of complex congenital conditions.

BACKGROUND: Coronavirus disease 2019 (COVID-19) causes a range of illness severity. Mild illness has been reported, but whether illness severity correlates with infectivity is unknown. We describe the public health investigation of a mildly ill, non-hospitalized COVID-19 case who traveled to China. METHODS: The case was a Maricopa County resident with multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive specimens collected on January 22, 2020. Contacts were persons exposed to the case on or after the day before case diagnostic specimen collection. Contacts were monitored for 14 days after last known exposure. High-risk contacts had close, prolonged case contact (>/=10 minutes within 2 meters). Medium-risk contacts wore all U.S. Centers for Disease Control and Prevention (CDC)-recommended personal protective equipment during interactions. Nasopharyngeal and oropharyngeal (NP/OP) specimens were collected from the case and high-risk contacts and tested for SARS-CoV-2. RESULTS: Paired case NP/OP specimens were collected for SARS-CoV-2 testing at 11 time points. In 8 pairs (73%), >/=1 specimen tested positive or indeterminate, and in 3 pairs (27%) both tested negative. Specimens collected 18 days after diagnosis tested positive. Sixteen contacts were identified; 11 (69%) had high-risk exposure, including 1 intimate contact, and 5 (31%) had medium-risk exposure. In total, 35 high-risk contact NP/OP specimens were collected for SARS-CoV-2 testing; all 35 pairs (100%) tested negative. CONCLUSIONS: This report demonstrates that SARS-CoV-2 infection can cause mild illness and result in positive tests for up to 18 days after diagnosis, without evidence of transmission to close contacts. These data might inform public health strategies to manage individuals with asymptomatic infection or mild illness.