Infectious Disease: Mosquito-Borne Viral Illnesses.

Due to rapid globalization and ease of travel, mosquito-borne viral infections are now a concern for family physicians throughout the United States. Zika virus infection is one such concern. It is spread via mosquito bites or by sexual contact with an infected individual. Most patients are asymptomatic, and when symptoms occur, they are mild and nonspecific. The main concern is the potential of the infection to cause fetal anomalies. Dengue is another mosquito-borne viral infection. Symptoms of initial infection are mild, and may include arthralgias. Subsequent infection with a different serotype can cause life-threatening hemorrhagic fever or shock. Chikungunya virus infection is widespread in the Americas and symptoms are similar to those of dengue. However, it can cause a postviral chronic inflammatory rheumatism in up to half of patients. Yellow fever occurs mostly in sub-Saharan Africa and can cause hepatic failure. Encephalitis viruses, most commonly West Nile in the United States and others such as Japanese encephalitis virus, can cause neuroinvasive disease, most often in older adults. Vaccines are available for yellow fever and Japanese encephalitis viruses but the keys to prevention are insect avoidance, mosquito eradication, and use of mosquito repellants.