ABSTRACT
Background. West Nile virus (WNV) causes a mosquito-borne disease that can lead to permanent paralysis or death. WNV became endemic in Maricopa County in 2003. The Maricopa County Department of Public Health (MCDPH) and Environmental Services Department Vector Control (MCESD VC) and Arizona Department of Health Services (ADHS) collaborated to monitor and respond to mosquito surveillance and human WNV cases. We describe an unprecedented WNV outbreak in 2021. Methods. MCESD VC monitored vector complaints, mosquito vector positive traps, and vector index (VI) data. Reported human cases (using the CSTE/CDC case definition) were interviewed by MCDPH. MCDPH and ADHS sent surveillance alerts to healthcare providers regarding WNV symptomology and clinical testing guidance. MCDPH consulted with providers and/or Infection Preventionists during case investigations. Results. The first WNV-positive mosquito trap occurred the week of May 1 (VI=0.235);VI peaked the week of September 11 at 53.608;the last positive trap was the week of November 20. MCESD VC fogged >400,000 acres (~2x the 10-year average) with adulticide, applied larvicide to ~25,000 sites, and received ~9,500 mosquito complaints (40% more than prior season). During the 2021 WNV season, 1,487 cases were reported, of which 960 (64.6%) had neuroinvasive illnesses (WNND) and 101 (6.8%) died (all were WNND cases). Median case age was 66 (IQR=53-75) years;for deaths, it was 79 (IQR=71-83) years. In total, 1,017 (68.4%) cases were hospitalized with a median length of stay (LOS) of 7 (IQR=4-10) days. WNND cases accounted for 91.2% of hospitalizations. Median LOS for hospitalized WNND cases was 7 (IQR=4-11) days, compared to 4 (IQR=2-6) days for nonneuroinvasive cases. Despite 3 surveillance alerts sent to providers and media coverage, providers were not consistently aware of the WNV outbreak or that serum can be tested for WNV. Conclusion. This was the largestWNVoutbreak in Maricopa County. It taxed an already stressed healthcare system during the COVID-19 pandemic with over 1,000 hospitalized cases, including nearly 100 in people without WNND. During WNV season, clinicians should consider WNV testing of both serum and CSF in severely ill patients with and without evidence of neuroinvasive disease.
ABSTRACT
Background: In young adults and adolescent males, myocarditis has been described as a rare complication of SARS-CoV-2 mRNA-vaccination. Reported findings include chest pain, elevated troponin levels, and cardiac MRI abnormalities. ECG abnormalities include ST-elevation but to our knowledge, ventricular arrhythmia has not been yet described. In the vast majority of reported cases, symptoms were relatively mild and patients recovered fully. Method: Here, we report two male adolescents (15 resp. 13 years old) admitted to our hospital with nonsustained (ns) VT and chest pain (patient no. 1) and near syncope (patient no. 2) after receiving an mRNA-SARS-CoV-2 vaccine (patient no. 1: 4 days after the second dose and patient no. 2: 15 days after days after the first dose). Further workup included family history, standard 12 lead ECG, the Holter monitoring, heart catheterization, myocardial biopsy, invasive programmed RV stimulation, and cardiac MRI. Results: Both patients did not have elevated troponin levels nor specific ECG findings. Family history was free for cardiac diseases, sudden cardiac death, or syncopal episodes. The Holter monitoring showed recurrent ns VT in one patient. Cardiac MRI and myocardial biopsy in both patients did not show evidence of myocarditis, but both patients showed severe thickening of the arterioles in myocardial biopsy. Invasive RV-stimulation did not trigger VT. Ultimately, both patients did not meet diagnostic criteria for myocarditis and β-blockers were started for ns VT. As of today, four more patients in age group 12 to 17 years were diagnosed with vaccine-associated myocarditis in our institution and one male with COVID-19 associated myocarditis. Notably, none of these patients had ventricular tachycardia or other cardiac arrhythmia. Conclusion: We observed ventricular tachycardia after SARS-CoV-2-mRNA vaccination in two adolescent males. This manifestation seems to be distinct from the well-described vaccine-associated myocarditis. Interestingly in both patients, perivascular thickening of arterioles was noted in biopsy. The mechanism and causality of ventricular arrhythmia in association with SARS-CoV-2 mRNA vaccines remain unclear and requires further observation.