Health Information Portal (HIP)

Arboviruses

Topic	Priority Priority Alert Conveys the highest level of importance; warrants immediate action or attention. Advisory Provides important information for a specific incident or situation; may not require immediate action. Notification Provides information regarding an incident or situation; unlikely to require immediate action. Update Provides updated information regarding an incident or situation; unlikely to require immediate action.	Date of Alert
Increased Risk of Dengue and Oropouche Virus Infections: Clinical Recognition and Management	Advisory	Oct 3, 2024
Increased Seasonal Risk for West Nile Virus Infection: Clinical Recognition and Testing Reminders	Advisory	Aug 20, 2024
First Symptomatic West Nile Virus Cases Identified for the 2023 Season	Advisory	Sep 18, 2023
First Neuroinvasive West Nile Virus Cases Identified for the 2022 Season	Advisory	Aug 29, 2022
Testing and Reporting Requirements for West Nile Virus and Other Arboviruses	Advisory	Jun 9, 2022

Surveillance

• PDPH West Nile Virus Surveillance
• PDPH Zika and Other Travel-Related Arboviruses Surveillance
• CDC West Nile Virus Surveillance
• CDC Dengue Surveillance
• CDC Chikungunya Geographic Distribution
• CDC Zika Virus Geographic Distribution

Vaccine Information

There are no vaccines currently 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, collect cerebrospinal fluid and serum for WNV IgM and IgG testing from patients who present with suspected WNV infections or unexplained encephalitis or meningitis. WNV-specific IgM in serum or CSF is preferred for laboratory confirmation. Consider the specimen type and timing of collection when ordering WNV-specific IgM testing.

• Serum: Collect 8 to 14 days after illness onset. Draw and test additional serum if collected too early.
• CSF: Collect within 8 days of illness onset. Polymerase Chain Reaction (PCR) or culture for other viral etiologies (i.e., herpes simplex virus, enterovirus, etc) should also be ordered.

A 4-fold increase in WNV-specific IgG titers from acute and convalescent serum collected at least 2-weeks apart can also confirm diagnosis. Contact the Division of Disease Control at 215-685-6742 to help facilitate specimen submission to the PA Department of Health laboratory for confirmatory testing.

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 laboratory and PDPH should be contacted at 215-685-6742 for testing requests (see 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)
  *Note: Dengue PCR availability is limited
• Day 4 to 7 of illness: Order PCR, IgM, & IgG
• Day 8 and after: Order IgM, & IgG

For detailed information on screening and testing pregnant people and their infants for Zika, click here to view the Zika Virus Guidance page.

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 mosquito repellent
  • Stay in well-screened, air-conditioned accommodations
  • Wear long pants and sleeves when weather permits
  • Remove standing water outside the home twice a week
• 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
• See the Zika Guidance page for information on the prevention of sexual transmission of Zika and congenital Zika infections

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

• CDC West Nile Virus Information for Healthcare Providers
• Diagnostic Testing Algorithm for Suspected West Nile Virus Disease

Clinical Guidelines for Chikungunya

• CDC Chikungunya Information for Healthcare Providers
• Chikungunya Virus – An Emerging Threat to the Americas [CDC, 2014]

Clinical Guidelines for Dengue

• World Health Organization’s Dengue Guidelines for Diagnosis, Treatment, Prevention and Control
• CDC Dengue Clinical Case Management Course (Free CME)

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.

Health Educational Materials

• West Nile Virus Fact Sheet [PDPH, 2011]
• Dengue Fact Sheet [PDPH, 2011]
• Chikungunya Fact Sheet [PDPH, 2011]
• Zika Virus Fact Sheet (Spanish) [PDPH, 2016]
• PDPH Zika and Pregnancy Brochure for Obstetrician Waiting Rooms (Spanish) [PDPH, 2016]
• Zika and Pregnancy 11x17 Poster for Obstetrician Waiting Rooms (Spanish) [PDPH, 2016]
• CDC Clinical Considerations for Pregnant Persons with Possible Zika Virus Infection
• CDC Congenital Zika Syndrome and Other Birth Defects

Links and Resources

• Pennsylvania Department of Health WNV Specimen Submission Form
• CDC Division of Vector-Borne Diseases Homepage
• CDC West Nile Virus Homepage
• CDC Yellow Book - Health Information for International Travel
• CDC Zika Virus Homepage
• Zika Virus - What Clinicians Need to Know [COCA Conference Call, January 26, 2016]

For Patients and Community Members:

Posters:

There are no posters for Arboviruses.