One-dose universal varicella vaccination (UVV) was introduced in the Argentinian National Immunization Program in July 2015. This study examined the impact of one-dose UVV on varicella incidence and mortality in Argentina. Incidence and mortality data were obtained from official databases for pre-UVV (January 2008–June 2015) and post-UVV (July 2015–December 2019) periods. Time series analyses with autoregressive integrated moving average (ARIMA) modeling predicted varicella incidence and mortality in absence of UVV in the target (aged 1–4 years) and overall population. Predicted and observed values post-UVV were compared to estimate UVV impact. Mean annual incidence rates per 100,000 reduced from 1999 (pre-UVV) to 1122 (post-UVV) in the target population and from 178 to 154 in the overall population. Significant declines in incidence were observed, reaching reductions of 83.9% (95% prediction interval [PI]: 58.9, 90.0) and 69.1% (95% PI: 23.6, 80.7) in the target and overall populations, respectively, during peak months (September-November) post-UVV. Decreasing trends in mortality rate from 0.4 to 0.2 per 1,000,000 population were observed. Over the last four years, one-dose UVV has significantly reduced varicella burden of disease in Argentina. Continuous efforts to improve vaccination coverage rates and long-term follow-up are needed to better understand the benefits of the UVV program.

Extrapulmonary tuberculosis accounts for 15-20 % of all clinical presentations of tuberculosis. Peripheral tuberculous lymphadenitis is the second most common presentation of extrapulmonary tuberculosis in children, after pleural tuberculosis, in Argentina. We analyzed 92 patients with peripheral tuberculous lymphadenitis seen at the Department of Tisiology of Hospital de Ninos "Dr. Ricardo Gutierrez" between August 2000 and September 2015. The patients' mean age was 8.7 +/- 5 years. Nodal sites corresponded to single peripheral (31.5 %), multiple peripheral (20.6 %), and peripheral associated with deep nodes (47.8 %). Cervical lymph nodes were the most common site of involvement (80 %). In 80 % of patients previous antibiotic therapy had been administered, without response. The tuberculosis source was known in 56 %; 69 % had a positive tuberculin skin test; and 54 %, a pathological chest X-ray. Tuberculosis treatment was started on all patients based on clinical criteria, exposure and/or positive tuberculin skin test, prior to microbiological or histological confirmation. The clinical course was either healing (81.5 %), referral to a facility near home (8.7 %) or dropout (8.7 %). One patient died.

Introduction. In Argentina, an estimated 400 000 varicella cases occur annually. Given the under-recording of existing cases, the actual burden of disease is unknown. Objective. To assess the burden of varicella before the introduction of the varicella vaccine in the national immunization schedule. Materials and methods. Retrospective, analytical, observational study carried out in three hospitals of Argentina. Review of medical records from outpatient visits to the Emergency Department and from patients younger than 18 years hospitalized for varicella. Period:1/2011-12/2013. Results. A total of 382 782 outpatients were seen; 3367 (0.88% )corresponded to visits due to varicella; 57.6 % were <= 4 years old. A total of 164 (4.9 %) patients required hospitalization, with an overall hospitalization rate of 65.3/10 000 hospitalized patients/ year (95 % confidence interval [CI]: 55.4-76.5); hospitalization rate in healthy children: 57.2/10 000 (95 % CI: 67.7-48.0); median age: 31.5 months. The most common causes of hospitalization were skin and/or soft tissue infections (61.1 %) and respiratory infections (10.1 %). Also, 54.3 % were treated with acyclovir and 73.1 %, with antibiotics. Bacteremia developed in 5/67 patients (7.5 %), all cases were caused by Gram-positive cocci and occurred in immunocompetent patients. Out of 19 immunocompromised patients, 36.8 % had complications (5 skin and/or soft tissue infection and 2 pneumonia cases). The median length of stay was 4 days, which is significantly more prolonged in immunocompromised patients. One patient required intensive care. No patient died. Conclusion. The burden of disease was significant, with a considerable impact in patients without an underlying disease.

Infectious Spondylodiscitis is a rare infection in children. It is more frequent in patients under 6 years of age. We report the case of an 8-year-old patient with lumbar pain for 2 months, without fever. Xrays, computed tomography and magnetic resonance imaging all three showed spondylodiscitis L4-L5. After a 10-day antibiotic treatment with clindamycin with regular response, a bone puncture was performed isolating Kingella kingae (Kk). Ostearticular infections caused by Kk have increased among infants and children. Due to improvement in culture techniques, the usage of automatic systems and assessment molecular techniques, these infections re-emerged in the past few years. Kk is a pathogen that has lately become significant in osteoarticular infections.