Epidemiologic Analysis of Chilblains Cohorts Before and During the COVID-19 Pandemic.

Importance: Beginning in March 2020, case reports and case series linked the COVID-19 pandemic with an increased occurrence of chilblains, but this association has not been evaluated in an epidemiologic study. Objective: To assess whether a correlation exists between COVID-19 incidence and chilblains incidence. Design, Setting, and Participants: A retrospective cohort study was conducted within the Kaiser Permanente Northern California system from January 1, 2016, to December 31, 2020; health plan members of all ages were included. Exposure: COVID-19 incidence in 207 location-months, representing 23 geographic locations in northern California across 9 months. Main Outcome and Measures: Chilblains incidence was the main outcome. The association of chilblains incidence with COVID-19 incidence across the 207 location-months was measured using the Spearman rank correlation coefficient. Results: Of 780 patients with chilblains reported during the pandemic, 464 were female (59.5%); mean (SD) age was 36.8 (21.8) years. COVID-19 incidence was correlated with chilblains incidence at 207 location-months (Spearman coefficient 0.18; P = .01). However, only 17 of 456 (3.7%) patients with chilblains tested during the pandemic were positive for SARS-CoV-2, and only 9 of 456 (2.0%) were positive for SARS-CoV-2 within 6 weeks of the chilblains diagnosis. Test results of 1 of 97 (1.0%) patients were positive for SARS-CoV-2 IgG antibodies. Latinx patients were disproportionately affected by COVID-19 but not by chilblains. Conclusions and Relevance: This cohort study found that in northern California, the incidence of chilblains increased during the pandemic but was correlated weakly with the incidence of COVID-19 across 207 location-months. These findings may have resulted from a causal role of COVID-19, increased care-seeking by patients with chilblains during the pandemic, or changes in behavior during shelter in place.

The changing epidemiology of serious bacterial infections in young infants.

BACKGROUND: Management of febrile young infants suspected of having serious bacterial infections has been a challenge for decades. The impact of changes in prenatal screening for Group B Streptococcus and of infant immunizations has received little attention in population-based studies. METHODS: This study analyzed all cultures of blood, urine and cerebrospinal fluid obtained from full-term infants 1 week to 3 months of age, who presented for care at Kaiser Permanente Northern California during a 7-year period utilizing electronic medical records. RESULTS: A total of 224,553 full-term infants were born during the study period. Of 5396 blood cultures, 129 bacteremic infants were identified (2%). Of 4599 urine cultures, 823 episodes of urinary tract infection (UTI) were documented in 778 infants (17%). Of 1796 CSF cultures, 16 infants had bacterial meningitis (0.9%). The incidence rate of serious bacterial infections (bacteremia, UTI and meningitis) and febrile serious bacterial infections was 3.75 and 3.1/1000 full-term births, respectively. Escherichia coli was the leading cause of bacteremia (78), UTI (719) and bacterial meningitis (7). There were 23 infants with Group B Streptococcus bacteremia including 6 cases of meningitis and no cases of Listeria infection. Nine percentage of infants had multiple sites of infection; 10% of UTIs were associated with bacteremia and 52% of bacteremia was associated with UTI. CONCLUSIONS: Compared with earlier studies, UTIs now are found significantly more often than bacteremia and meningitis with 92% of occult infections associated with UTIs. These data emphasize the importance of an urinalysis in febrile infants.

Changing epidemiology of bacteremia in infants aged 1 week to 3 months.

BACKGROUND: Bacteremia in young infants has remained an important ongoing concern for decades. Despite changes in prenatal screening and infant immunizations, the current epidemiology of this problem has received little attention. METHODS: We conducted a retrospective analysis of all blood cultures collected at Kaiser Permanente Northern California on full-term, previously healthy infants presenting for care between 1 week to 3 months of age for whom a blood culture was drawn from January 1, 2005, through December 31, 2009. RESULTS: During the study period, 4255 blood cultures were collected from 160 818 full-term infants. Only 2% of all blood cultures were positive for pathogens (93/4255), whereas 247 positive cultures were due to contaminants. The incidence rate of true bacteremia was 0.57 in 1000 full-term births. The most common pathogen was Escherichia coli (56%). Ninety-eight percent of infants with E coli bacteremia had a urinary tract infection. Group B Streptococcus and Staphylococcus aureus were the second and third most common pathogens, respectively. There were no cases of Listeria monocytogenes bacteremia or meningococcemia and only 1 case of enterococcal bacteremia. Ampicillin resistant pathogens accounted for 36% of organisms. CONCLUSIONS: Our study indicates bacteremia in young infants occurs infrequently and in only 2.2% of those who had a blood culture drawn. On the basis of the epidemiology of pathogens found in this large cohort, these data suggest a change in currently recommended presumptive antibiotic coverage in 1-week to 3-month-old infants with suspected bacteremia.

Changing epidemiology of outpatient bacteremia in 3- to 36-month-old children after the introduction of the heptavalent-conjugated pneumococcal vaccine.

BACKGROUND: The introduction of routine vaccination with heptavalent conjugated pneumococcal vaccine has changed the overall incidence of bacteremia in children 3 months-3 years old. OBJECTIVE: To describe the changing incidence and etiology of bacteremia in previously healthy toddlers presenting to outpatient clinical settings. METHODS: Retrospective case series of all blood cultures obtained between September 1998 and August 2003 in Kaiser Permanente Northern California outpatient clinics and emergency departments from previously healthy children 3 months-3 years old. RESULTS: Implementation of routine vaccination with the conjugated pneumococcal vaccine resulted in an 84% reduction of Streptococcus pneumoniae bacteremia (1.3-0.2%) and a 67% reduction in overall bacteremia (1.6-0.7%) in the study population. The rate of blood culture isolation of contaminating organisms remained unchanged at 1.8%; therefore, by the end of the study, >70% of organisms identified in blood cultures were contaminants. During the 5 study years, total blood cultures drawn decreased by 35% in outpatient pediatric clinics but remained unchanged in emergency departments. By 2003, one-third of all pathogenic organisms isolated from blood cultures were Escherichia coli, one-third were non-vaccine serotype S. pneumoniae, the majority of the remaining one-third were Staphylococcus aureus, Salmonella spp., Neisseria meningitidis and Streptococcus pyogenes. In our population of children routinely immunized with the conjugated pneumococcal vaccine, a white blood cell count >15,000 by itself is a poor predictor of bacteremia in the febrile toddler (sensitivity, 74.0%; specificity, 54.5%; positive predictive value, 1.5%; negative predictive value, 99.5%). CONCLUSION: In the United States, routine vaccinations with Haemophilus influenzae type b and S. pneumoniae vaccines have made bacteremia in the previously healthy toddler a rare event. As the incidence of pneumococcal bacteremia has decreased, E. coli, Salmonella spp. and Staphylococcus aureus have increased in relative importance. The use of the white blood cell count alone to guide the empiric use of antibiotics is not indicated. New guidelines are needed to approach the previously healthy febrile toddler in the outpatient setting.

Perceived risks and benefits of HIV testing, and predictors of acceptance of HIV counselling and testing among pregnant women in Zimbabwe.

This project evaluated perceived risks and benefits and determined predictors of acceptance of voluntary HIV counselling and testing (VCT) among pregnant women in Zimbabwe. One hundred and seventy pregnant women attending an urban antenatal clinic were surveyed. Implications of a negative or positive HIV test result and of telling a partner or community members that one is HIV positive were queried. Forty women (23.5%) consented to VCT, and 16 (40%) were HIV positive. Women who saw VCT as lower risk (odds ratio [OR] = 2.3, 95% confidence interval [CI] [1.1-5.0]) and women who had had a stillbirth or child die (OR = 0.4, 95% CI [0.16-0.97]) were more likely to consent. Prenatal HIV VCT offers the best opportunity for prevention of mother-to-child transmission of HIV; however, less than 25% of women consented. If such interventions are to be successful, attention must be directed towards developing culturally appropriate strategies to address women's concerns and improve future acceptance of VCT in Zimbabwe.

Viral dynamics of early HIV infection in neonatal macaques after oral exposure to HIV-2287: an animal model with implications for maternal-neonatal HIV transmission.

A model of vertical HIV transmission was developed using oral HIV-2(287) exposure of newborn Macaca nemestrina. The minimal Animal Infectious Dose for this oral route was found to be 10-fold higher than that for atraumatic viral transmission across other mucosal membranes (vaginal/rectal) of juvenile macaques. However, once infection was established, viral replication was rapid and plasma viremia could be detected by reverse-transcriptase polymerase chain reaction and viral co-culture within 1 week following exposure. No animal was resistant to infection and all macaques initially exposed to a subinfectious viral inoculum were subsequently infected by re-exposure of mucosal membranes. Higher viral load during primary infection correlated with a more rapid CD4 depletion; however, all HIV-2(287)-infected animals developed CD4 depletion during the observation period. This animal model can now be used to study early viral replication in the presence and absence of anti-retroviral agents to help identify conditions to reduce vertical HIV transmission in human newborns.