Table 1.
Mosquito-borne viral emerging infectious diseases
| Name | Epidemiology | Transmission | Clinical Manifestations | Diagnosis | Management | Prevention |
|---|---|---|---|---|---|---|
| Yellow fever | Endemic in sub-Saharan Africa, Central & South America & Caribbean; endemic in 47 different countries. In United States, all cases imported & in unimmunized travelers to risk areas True incidence unknown due to lack of surveillance |
Zoonotic infection spread by mosquitoes in Americas A aegypti Potential for rapid spread by international travelers Mosquitoes acquire the virus by feeding on infected primates (human or nonhuman) transmitting virus to other primates. People infected with yellow fever virus are viremic shortly before the onset of fever and up to 5 d after onset Yellow fever virus has 3 transmission cycles: jungle (sylvatic), intermediate (savannah), and urban The urban cycle involves transmission of the virus between humans and mosquitoes, primarily. Virus brought to the urban setting by a viremic human who was infected in the jungle or savannah |
Incubation 3–6 d. Wide spectrum including asymptomatic. Early flulike symptoms: fever, malaise, myalgia, headache, vomiting. Majority will have bimodal disease. Fever returns within 24 h: hepatitis, jaundice, renal failure. In severe cases, hemorrhage & shock. Among those who develop severe disease, 30%–60% die Most people with the initial symptoms improve within 1 wk. Residual weakness and fatigue might last several months |
Yellow fever infection is diagnosed based on laboratory testing, symptoms, and travel history Difficult in early phase: confused with malaria and other Flaviviruses |
Supportive & symptomatic care Avoid certain medications, such as aspirin or other nonsteroidal anti-inflammatory drugs, which increase the risk of bleeding No specific antiviral treatment IV gamma globulin in early infection WHO considers confirmed case as seminal event indicating transmission: mass vaccination is required. Issue is not enough vaccine. Vaccine-sparing strategies to immunize enough people for herd immunity & population protection |
Control of vector & prevention of mosquito bites Use Environmental Protection Agency–registered insect repellents, for example, DEET, Picaridin One vaccine yellow fever-Vax (Sanofi Pasteur, Swiftwater, PA, USA) approved by Food and Drug Administration in United States (www.cdc.gov/vaccines) CDC & WHO recommend those traveling and living in endemic areas receive 1 dose |
| Chikungunya virus Ramachandran et al,16 2016 & Rathore et al,14 2017 |
Endemic to Africa & Asia | Arbovirus like Zika, yellow fever, and dengue transmitted by mosquito (A aegypti) (see previous discussion on yellow fever). Recent outbreaks in Europe and Americas (including United States) | Can cause infections in adults & children. Up to 28% asymptomatic. Incubation 3–7 d. Abrupt onset high fever for up to 2 wk, severe polyarthralgia, transient skin rash maculopapular on trunk and extremities. Relapse may occur 2–3 mo after onset. At risk are older adults (>65), persons with comorbidities, neonates exposed intrapartum. Infants & children high risk of atypical or severe disease, for example, vesiculobullous lesions, neurologic complications | Differential diagnosis, dengue fever, malaria, leptospirosis, group A streptococcus, rubella, measles, parvovirus Laboratory tests combined with history. In United States, laboratory test at CDC. Rely on detection of the virus |
No specific antiviral treatment Supportive management. Only acetaminophen for joint pain & fever until determined is not dengue fever |
Focus on vector control and avoiding further bites to humans to disrupt mode of transmission of infection (see previous discussion on yellow fever) No licensed vaccine for virus, although WHO is evaluating several |
| Dengue virus | Global arboviral Endemic in more than 120 countries, for example, SE Asia & Western Pacific areas, Caribbean, Latin America, some regions of the United States, Africa, Middle East 3.9 billion at risk worldwide. In 2016, large outbreaks worldwide affecting children and adults. Epidemics in the United States in eighteenth and early twentieth centuries. Reemerged in 2016 (Texas & Hawaii) −764 confirmed cases |
Transmitted by Aedes genus of mosquito (primarily A aegypti) Four antigenically distinct virus serotypes, all RNA viruses belonging to Flavivirus (also includes yellow fever, West Nile, Zika, among others) |
WHO defines in terms of complexity: without warning signs (fever with nausea/vomiting; rash, myalgias); with warning signs (in addition to above, abdominal pain, clinical fluid accumulation, lethargy); severe dengue (all of the above with severe plasma leakage, severe bleeding) | Confirmatory tests: viral antigen or nucleic acid detection & serology. Difficult to distinguish clinically from Zika & chikungunya virus infections | No specific antiviral agent. Fluid therapy |
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