February 16, 2016
Ron Rosenberg, ScD
Division of Vector-Borne Diseases
National Center for Emerging & Zoonotic Infectious Diseases
The Yap Epidemic Duffy et al, 2009, N Engl J Med 360:2536
• April - July, 2007 • Macropapular rash, conjunctivitis, fever, arthralgia • dengue IgM negative
• Lab diagnosis protocol • Positive: PCR+ or IgM+, PRNT90 >20 & dengue PRNT90 >4 • Probable: IgM+, PRNT90 >20 & dengue PRNT90 <4
• Sought care (n=185): • 49 confirmed, 59 probable, 72 suspect Zika
• Household survey (n=557): • 74% IgM+, 19% ill
• Aedes hensilli: 36% of containers
Zika Virus - Basics
Genus Flavivirus (Family Flaviviridae)
26 vector-borne human pathogens, 1 non-arbovirus
tick & mosquito vectors
neuroinvasive or hemorrhagic
Discovery
Rockefeller Foundation dedicated to arbovirus discovery
1947 (sentinel macaque), 1948 (mosquito), 1954 (human)
Sequence: Kuno & Chang, January, 2007 (Arch. Virol. 152:687)
1947 Discovery
The Spread of Zika Virus Discovery
1947 Discovery
The Spread of Zika Virus Discovery
1954 1st Human
1947 Discovery
The Spread of Zika Virus Discovery
1954 1st Human
1954-2007 Asia
1947 Discovery
The Spread of Zika Virus Discovery
1954 1st Human
1954-2007 Asia
2007-2014 Pacific
1947 Discovery
The Spread of Zika Virus Discovery
1954 1st Human
1954-2007 Asia
2007-2014 Pacific
2015 Americas
South Pacific Outbreaks
• 2013 – French Polynesia
• Estimated 28,000 (11% population) – clinically similar to Yap, but…
• First suspect association Guillan-Barré syndrome
• 2015 retrospective case review: increase in microcephaly
• 2014 – New Caledonia, Cook Islands, Solomons, Easter Island
• Asian genotype – Yap, Cambodia
Kraemer MUG, et alii, eLife 2015;4:e08347
Actual & Potential Geographic Distribution of Aedes aegypti
Some Things We Need or Need to Know
• Infection course • Length of viremia, asymptomatic infectivity, antibody profile
• Birth defects, GBS • Incidence • Risk factors (co-morbidities) • Has mutation increased risk?
• Risk of non-vectored transmission • Transfusion, transplantation • Sexual
• Diagnostics • Serology – poor specificity in dengue endemic areas • RNA in urine?
• Ecology • Animal reservoirs • Vector species
• and 200 other obscure or “non-pathogenic” arboviruses….
For more information, contact CDC 1-800-CDC-INFO (232-4636) TTY: 1-888-232-6348 www.cdc.gov The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.
