On July 31, 2020, this report was posted as an MMWR Early Release on the MMWR website (https://www.cdc.gov/mmwr). Limited data are available about transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), among youths. During June 17-20, an overnight camp in Georgia (camp A) held orientation for 138 trainees and 120 staff members; staff members remained for the first camp session, scheduled during June 21-27, and were joined by 363 campers and three senior staff members on June 21. Camp A adhered to the measures in Georgia's Executive Order* that allowed overnight camps to operate beginning on May 31, including requiring all trainees, staff members, and campers to provide documentation of a negative viral SARS-CoV-2 test ≤12 days before arriving. Camp A adopted most † components of CDC's Suggestions for Youth and Summer Camps § to minimize the risk for SARS-CoV-2 introduction and transmission. Measures not implemented were cloth masks for campers and opening windows and doors for increased ventilation in buildings. Cloth masks were required for staff members. Camp attendees were cohorted by cabin and engaged in a variety of indoor and outdoor activities, including daily vigorous singing and cheering. On June 23, a teenage staff member left camp A after developing chills the previous evening. The staff member was tested and reported a positive test result for SARS-CoV-2 the following day (June 24). Camp A officials began sending campers home on June 24 and closed the camp on June 27. On June 25, the Georgia Department of Public Health (DPH) was notified and initiated an investigation. DPH recommended that all attendees be tested and self-quarantine, and isolate if they had a positive test result. A line list of all attendees was obtained and matched to laboratory results from the State Electronic Notifiable Disease Surveillance System ¶ and data from DPH case investigations. A COVID-19 case associated with the camp A outbreak was * https://gov.georgia.gov/document/2020-executive-order/06112001/download. † Notable adopted measures included cohorting of attendees by cabin (≤26 persons), staggering of cohorts for use of communal spaces, physical distancing outside of cabin cohorts, and enhanced cleaning and disinfection, especially of shared equipment and spaces.

BACKGROUND: Very low birth weight (VLBW) and premature infants are at risk for developing postnatal cytomegalovirus (CMV) disease, including CMV-related sepsis-like syndrome (CMV-SLS) for which in the United States are lacking. METHODS: We performed a systematic review and meta-analysis to estimate the pooled proportions (and 95% confidence intervals) of VLBW and premature infants born to CMV-seropositive women with breast milk–acquired CMV infection and CMV-SLS. We combined these proportions with population-based rates of CMV seropositivity, breast milk feeding, VLBW, and prematurity to estimate annual rates of breast milk–acquired CMV infection and CMV-SLS in the United States. RESULTS: In our meta-analysis, among 299 infants fed untreated breast milk, we estimated 19% (11%–32%) acquired CMV infection and 4% (2%–7%) developed CMV-SLS. Assuming these proportions, we estimated a rate of breast milk–acquired CMV infection among VLBW and premature infants in the United States of 6.5% (3.7%–10.9%) and 1.4% (0.7%–2.4%) of CMV-SLS, corresponding to 600 infants with CMV-SLS in 2008. Among 212 infants fed frozen breast milk, our meta-analysis proportions were 13% (7%–24%) for infection and 5% (2%–12%) for CMV-SLS, yielding slightly lower rates of breast milk–acquired CMV infection (4.4%; 2.4%–8.2%) but similar rates of CMV-SLS (1.7%; 0.7%–4.1%). CONCLUSIONS: Breast milk–acquired CMV infection presenting with CMV-SLS is relatively rare. Prospective studies to better define the burden of disease are needed to refine guidelines for feeding breast milk from CMV-seropositive mothers to VLBW and premature infants.

Summary Background Congenital cytomegalovirus (CMV) infection is the leading infectious cause of congenital hearing loss and neurodevelopmental disability in developed countries. Information on congenital CMV infection in developing countries appears to be lacking. Methods We conducted a systematic literature review to identify studies from developing countries with population-based samples of at least 300 infants that used laboratory methods established as reliable for the diagnosis of congenital CMV infection. Results Most studies were excluded due to biased samples or inadequate diagnostic methods; consequently the search identified just 11 studies that were from Africa, Asia, and Latin America. The number of newborns tested ranged from 317 to 12 195. Maternal CMV seroprevalence ranged from 84% to 100%. CMV birth prevalence varied from 0.6% to 6.1%. CMV-associated impairments were not documented in most studies. Conclusions Birth prevalence ranges were higher than for Europe and North America, as expected based on the higher maternal CMV seroprevalence. With very limited data available on sequelae, the disease burden of congenital CMV in developing countries remains largely unknown at this time.

Objectives To assess the prevalence, characteristics, and risk of sensorineural hearing loss (SNHL) through 18 years of age in children with congenital CMV infection identified through hospital-based newborn screening who were asymptomatic at birth compared to uninfected children. Methods We included 92 case-patients and 51 controls assessed using auditory brainstem response and behavioral audiometry. We used Kaplan-Meier survival analysis to estimate prevalence of SNHL, defined as ≥25 dB hearing level (HL) at any frequency, and Cox proportional hazards regression analyses to compare SNHL risk between groups. Results At the end of follow-up, SNHL prevalence was 25% (95% CI: 17–36%) among case-patients and 8% (95% CI: 3–22%) in controls (hazard ratio (HR): 4.0; 95% CI: 1.2–14.5; p-value=0.02). Among children without SNHL by age 5 years, the risk of delayed-onset SNHL was not significantly greater for case-patients than for controls (HR: 1.6; 95% CI: 0.4–6.1; P=0.5). Among case-patients, the risk of delayed-onset SNHL was significantly greater among those with unilateral congenital/early-onset loss than those without (hazard ratio: 6.9; 95% CI: 2.5–19.1; P<0.01). At the end of follow-up, the prevalence of severe to profound bilateral SNHL among case-patients was 2% (95% CI: 1–9%). Conclusions Delayed-onset and progression of SNHL among children with asymptomatic congenital CMV infection continued to occur throughout adolescence. However, the risk of developing SNHL after age 5 years among case-patients was not different than in uninfected children. An estimated 2% of case-patients developed SNHL severe enough to be candidates for cochlear implantation.

On May 21, 2021, this report was posted as an MMWR Early Release on the MMWR website (https://www.cdc.gov/mmwr).To meet the educational, physical, social, and emotional needs of children, many U.S. schools opened for in-person learning during fall 2020 by implementing strategies to prevent transmission of SARS-CoV-2, the virus that causes COVID-19 (1,2). To date, there have been no U.S. studies comparing COVID-19 incidence in schools that varied in implementing recommended prevention strategies, including mask requirements and ventilation improvements* (2). Using data from Georgia kindergarten through grade 5 (K-5) schools that opened for in-person learning during fall 2020, CDC and the Georgia Department of Public Health (GDPH) assessed the impact of school-level prevention strategies on incidence of COVID-19 among students and staff members before the availability of COVID-19 vaccines. † Among 169 K-5 schools that participated in a survey on prevention strategies and reported COVID-19 cases during November 16-December 11, 2020, COVID-19 incidence was 3.08 cases among students and staff members per 500 enrolled students. § Adjusting for county-level incidence, COVID-19 incidence was 37% lower in schools that required teachers and staff members to use masks, and 39% lower in schools that improved ventilation, compared with schools that did not use these prevention strategies. Ventilation strategies associated with lower school incidence included methods to dilute airborne particles alone by opening windows, opening doors, or using fans (35% lower incidence), or in combination with methods to filter airborne particles with high-efficiency particulate absorbing (HEPA) filtration with or without purification with ultraviolet germicidal irradiation (UVGI) (48% lower incidence). Multiple strategies should be implemented * Ventilation strategies include dilution methods (opening doors, opening windows, and using fans to improve circulation from open windows); filtration methods (installation of high-efficiency particulate absorbing [HEPA] filters); and purification methods (installation of ultraviolet germicidal irradiation [UVGI] units, installed in upper room areas and shielded from persons or installed in the heating, ventilation, and air conditioning [HVAC] system).

This cohort study assesses the sensitivity of dried blood spots polymerase chain reaction for newborn screening for congenital cytomegalovirus infection using saliva as the reference standard for screening, followed by collection of a urine sample for confirmation of congenital infection

In mid-2015, Salvador, Brazil, reported an outbreak of Guillain-Barré syndrome (GBS), coinciding with the introduction and spread of Zika virus (ZIKV). We found that GBS incidence during April–July 2015 among those ≥12 years of age was 5.6 cases/100,000 population/year and increased markedly with increasing age to 14.7 among those ≥60 years of age. We conducted interviews with 41 case-patients and 85 neighborhood controls and found no differences in demographics or exposures prior to GBS-symptom onset. A higher proportion of case-patients (83%) compared to controls (21%) reported an antecedent illness (OR 18.1, CI 6.9–47.5), most commonly characterized by rash, headache, fever, and myalgias, within a median of 8 days prior to GBS onset. Our investigation confirmed an outbreak of GBS, particularly in older adults, that was strongly associated with Zika-like illness and geo-temporally associated with ZIKV transmission, suggesting that ZIKV may result in severe neurologic complications.

The efficacy of licensed rotavirus vaccines has only been shown against certain rotavirus group A (RV-A) types. It is critical to understand the burden of rotavirus gastroenteritis (RVGE) and its prevalent types to assess the potential impact of these vaccines in Latin America and the Caribbean (LA&C). We performed a systematic review and meta-analyses of all the available evidence reported from 1990 to 2009 on the burden of rotavirus disease and strains circulating in LA&C. Eligible studies--185 country-level reports, 174 951 faecal samples--were selected from MEDLINE, Cochrane Library, EMBASE, LILACS, regional Ministries of Health, PAHO, regional proceedings, doctoral theses, reference lists of included studies and consulting experts. Arc-sine transformations and DerSimonian-Laird random-effects model were used for meta-analyses. The proportion of gastroenteritis cases due to rotavirus was 24.3% (95%CI 22.3-26.4) and the incidence of RVGE was 170 per 1000 children-years (95%CI 130-210). We estimated a global annual mortality for 22 countries of 88.2 (95%CI 79.3-97.1) deaths per 100 000 under 5 years (47 000 deaths).The most common G type detected was G1 (34.2%), followed by G9 (14.6%), and G2 (14.4%). The most common P types detected were P[8] (56.2%), P[4] (22.1%) and P[1] 5.4%, and the most prevalent P-G type associations were P[8]G1 17.9%, P[4]G2 9.1% and P[8]G9 8.8%. In the last 10 years, G9 circulation increased remarkably and G5 almost disappeared. More recently, G12 appeared and P[4]G2 re-emerged. To our knowledge, this is the first meta-analysis of rotavirus infection and burden of disease in LA&C.