Arboviruses
Surveillance
Local Surveillance
National Surveillance
Vaccine Information
There is no vaccine information available for Arboviruses.
Diagnosis & Management
West Nile Virus (WNV)
Clinical Characteristics
- Neuroinvasive WNV infection: meningitis, encephalitis or acute flaccid paralysis
- <1% of infected individuals develop WNV neuroinvasive disease
- May result in residual neurological deficits or death
- People who are at increased/higher risk include:
- adults >50 years old
- organ transplant recipients or immunocompromised patients
- WNV Fever
- 20% of infected individuals develop WNV fever
- Fever accompanied by other symptoms, such as headache, body aches, joint pains, vomiting, diarrhea, or rash
- Most recover completely, but fatigue and weakness can last for weeks or months
WNV Testing
Between May and October, clinicians should collect both serum and cerebrospinal fluid (CSF) for WNV testing from patients who have onset of unexplained encephalitis, meningitis, or acute flaccid myelitis. Serum can be tested for those with suspected WNV Fever. WNV-specific IgM in serum or CSF is preferred for laboratory confirmation.
Antibodies in serum are typically detectable 3–8 days after symptom onset. Absence of detectable antibodies in serum within 8 days of illness does not rule out WNV. Recollect serum after day 8 if there is ongoing concern for WNV. Testing of patients with neuroinvasive infections for other arboviral infections (e.g., Powassan, Jamestown Canyon virus, Eastern Equine Encephalitis, etc.) may also be considered, given detections of infected vectors in Pennsylvania and New Jersey.
Many commercial laboratories offer serologic or Polymerase Chain Reaction (PCR) testing for WNV. Any positive specimen should be forwarded to the Pennsylvania Department of Health Bureau of Laboratories (PADOH BOL) for confirmatory testing. For WNV or other arbovirus testing assistance, contact the Acute Communicable Disease Program at 215-685-6741.
Treatment
Treatment for WNV infection is supportive. Most patients with WNV fever or meningitis fully recover without long-term effects. Recovery from WNV encephalitis or acute flaccid myelitis can take several weeks to months with long-lasting neurologic deficits. The case fatality rate among persons with severe illness is 10%.
Chikungunya, Dengue, and Zika
Clinical Characteristics
Testing
If chikungunya, dengue, or Zika is suspected, collect serum and test for all three. Testing for all three pathogens is available through the PA Department of Health (PADOH) laboratory and PDPH should be contacted at 215-685-6742 for testing requests. View PADOH's arboviral collection instructions and specimen submission guidance. Commercial laboratories are offering arboviral testing, but assays available vary by laboratory, and providers will also need to place separate orders for each arbovirus (chikungunya, dengue, and Zika).
The type of assay(s) performed will depend on the time from illness onset to specimen collection.
- Day 1 to 3 of illness: Order polymerase chain reaction (PCR)
- Day 4 to 7 of illness: Order PCR, IgM, & IgG
- Day 8 and after: Order IgM, & IgG
Read CDC's clinical considerations for pregnant people with possible Zika virus infection for detailed information on screening and testing pregnant people and their infants for Zika.
The following laboratory results can help confirm diagnosis:
- Positive virus-specific PCR
- Positive virus-specific IgM titer with evidence of virus-specific neutralizing antibodies*
*Note: Neutralization tests that help differentiate arboviral pathogens are only available through public health laboratories - 4-fold change in virus-specific IgG titers from acute and convalescent serum (collected >2 weeks apart)
Treatment
- Patients with chikungunya or Zika should be managed as dengue with acetaminophen recommended for initial treatment.
- If dengue, which causes hemorrhagic complications, has been ruled out, NSAIDS or narcotics may be considered to manage fever and pain.
Guidelines for Management and Control
Prevention
- During warmer months (May-October) in Philadelphia and when traveling to areas with local transmission of chikungunya, dengue or Zika, encourage patients to take personal prevention measures:
- Use repellent with DEET, Picaridin, oil of lemon eucalyptus, or another EPA-registered product when outdoors. when outdoors.
- When weather permits, wear long-sleeved shirts and long pants.
- Keep well-fitted screens on windows and doors to keep out mosquitoes, along with using air conditioning.
- Regularly check and empty standing water outside the home (e.g., unused pools, tires, containers).
- Pregnant people or people planning to become pregnant due to the risk of congenital infection along with adults >65 years of age and persons with underlying conditions (e.g., hypertension, diabetes, etc.) who are at risk for severe disease should consider not traveling to areas with ongoing chikungunya or Zika outbreaks
- Advise patients with suspected chikungunya, dengue, or Zika infections to stay indoors and avoid mosquito bites for the first 7 days of illness to prevent local transmission
Prevention of Transmission for Returning Travelers
- Advise patients with suspected Zika, dengue, or chikungunya infections to stay indoors and avoid mosquito bites for the first 7 days of illness to prevent local transmission
Prevention of Sexual Transmission of Zika
- Since sexual transmission of Zika virus is possible and Zika virus may persist in semen longer than blood, providers should provide counseling to prevent sexual transmission to men who traveled to a country with Zika transmission and their partners.
- Those who have a pregnant partner should abstain from sexual activity or consistently and correctly use condoms during sex for the duration of the pregnancy
- Those with non-pregnant partners might consider abstaining from sexual activity or using condoms consistently and correctly during sex
- When more information on the duration seminal shedding becomes available, more definitive time frames for the prevention of sexual transmission will be provided
Clinical Guidelines for West Nile Virus
Clinical Guidelines for Chikungunya
Clinical Guidelines for Dengue
Clinical Guidelines for Zika
- CDC Clinical Signs and Symptoms of Zika Virus Disease
- Update: Interim Guidance for Health Care Providers Caring for Pregnant Women with Possible Zika Virus Exposure — United States (Including U.S. Territories), July 2017 [MMWR, July 28, 2017 / 66(29); 781-793]
- Interim Guidance for Zika Virus Testing of Urine — United States, 2016 [MMWR, May 13, 2016 / 65(18)]
- Interim Guidance for Interpretation of Zika Virus Antibody Test Results [MMWR, June 3, 2016 / 65(21)]
- Update: Interim Guidance for Preconception Counseling and Prevention of Sexual Transmission of Zika Virus for Men with Possible Zika Virus Exposure — United States, August 2018 [MMWR, August 10, 2018 / 67(31); 868-871]
- Pan American Health Organization (PAHO): Zika
Resources
For Healthcare Providers:
Reporting to PDPH
Report WNV cases immediately to PDPH by calling 215-685-6748 during business hours or calling 215-686-4514 after normal business hours. To arrange for testing and report suspected Zika cases, contact PDPH by calling 215-685-6742 during business hours.
Report dengue and chikungunya cases within 5 days by calling 215-685-6748 or faxing a disease report form to 215-238-6947.
Report WNV cases immediately to PDPH by calling 215-685-6748 during business hours or calling 215-686-4514 after normal business hours.
Health Educational Materials
Related Links
For Patients and Community Members:
There are no patient or community resources for Arboviruses.
Posters:
There are no posters for Arboviruses.