Bites That Suck (Mosquito Borne Illness in the US) Jesus Seda MD Objectives Review presentations of some Mosquito born illnesses Review ED evaluation and treatment Review Diagnostic Testing Treatment of Local Reactions Think Warm Thoughts Case 1 5 yo M presents in July with swelling to arm for a few hours after spending day outside. P: local pain E: erythema S: STS T: Tingling / paresthesia Local reaction Reaction varies by biting species Wanes over years Immune response dominant Local wheal & flare develops over 36 hours Bacterial superinfection uncommon! Usually takes days Zyrtec effective for itching & swelling (Karppinen, 2002) Steroids No specific studies Topical first or 7 day oral treatment No antibiotics if within hours Low grade fever Case 2 25 yo M p/w fever, nausea HA and fatigue Returned from Medical Mission in Haiti 1 month prior Trip of 5 weeks duration Rural village, no infrastructure Noncompliant with prophylaxis Initial Presentation Usually present due to high fevers Headache, malaise, rash Symptoms similar to viral illness/influenza Elicit travel history where, when, activity, length, bites VFR vs military travel Prophylaxis does not prevent disease Malaria: Historically in the USA 1 million deaths per year globally 1500 cases in US per year 2011 1900 cases 1947 15,000 Famous Sufferers: George Washington Abraham Lincoln Andrew Jackson Jesse James Malaria: transmission Caused by protozoa plasmodium Transmitted by anopheles mosquito Plasmodium falciparum >2% RBC load Severe : (pulmonary edema, ARF) Vivax, malariae and ovale Usually less severe disease Can lay dormant in liver for years Knowlesi: newly described in Asia Malaria: species distribution Malaria: Signs/Symptoms Fever 35% no fever (Svenson 1995) Fever cycles Hemolysis Jaundice Anemia Myalgias GI symptoms Partial Immunity Severe disease Cerebral malaria Seizures, decreased LOC Acute Kidney Injury Lactic acidosis Hypoglycemia Pulmonary edema Severe anemia (Hgb 2 cm Increase in HCT with rapid decrease in platelet count Dengue: Diagnosis WHO criteria 2 of the following Rash Arthralgia Nausea/vomiting Leukopenia Positive tourniquet test IgM/IgG and subtype serology available Doesnt change management Important for epidemiology Dengue: Treatment Proper hydration Watch for warning signs Outpatient treatment w/ 24 follow up Daily CBCs Avoid NSAIDs Avoid fluid overload during recovery phase No benefit from steroids Increased morbidly and GI bleeding Crystalloid more cost effective than colloids Colloids if not responding Transfuse Vaccines in phase 3 trial Case 4 60 yo F HA for 1 week, BIB family due to decreased LOC No significant travel history West Nile Virus: Distribution Endemic in all 48 states Transmitted by Culex Highest infection rates in summer/fall 2014 2205 total cases 1347 neuro-invasive Birds are reservoir West Nile Virus: Signs/Symptoms Invades CNS through unclear mechanism Cell lysis causes flaccid paralysis, impaired cognition Flaccid paralysis Damaged anterior horn cells GBS like demyelinating syndrome Most cases asymptomatic