zika virus, fertility and you
TRANSCRIPT
The Zika Virus, Fertility and You
Paul Turek MD, FACS, FRSMDirector, The Turek Clinics
Beverly Hills and San Francisco
Zika Infection History and Vectors
• Flavivirus similar to yellow fever, dengue, West Nile.
• Aedes sp. mosquitoes(Ae. aegypti and Ae.
albopictus) • Sexual intercourse• Maternal-fetal• Blood transfusion
(suspected)• All ages at risk of infection
CDC.gov
• First human case: Nigeria 1952• First epidemic: Yap, Micronesia, 2007• First large epidemic, French Polynesia, 2013• Latest epidemic: Brazil, 2015
Zika Infection-Symptoms
• Many have symptoms, but many don’t.
• Typically, fever rash, joint pain or red eyes.
• Also, muscle pain, headache.
• Lasts days to a week• Not lethal• Immune to future
infections
CDC.gov
Zika Infection-Risks
• Fetal microcephaly (less brain tissue and brain damage)
• Fetal eye, ear defects• Impaired growth and
joint issues (clubfoot)• Guillain-Barre Syndrome
CDC.gov
• Among n=442 fetuses in US Zika registry, 6% born with birth defects
• Among n=117 babies of Zika infected women in Rio, 42% were “grossly abnormal” at birth.
Zika Infection-Microcephaly Risk in Brazil
• Bahia, Brazil.• First trimester
infections.• Pink/solid are actual
cases.• White is 50% of actual
rate.• Gray is usual
incidence: <12/10,000 births
Johansson MA et al. NEJM. 2016; 375:1-4.
Zika Infection-Epidemiology of Worldwide Cases
CDC.gov
Lab confirmed cases as of 12/14/16. Excludes cases of travel only Zika infections
Zika Infection-Epidemiology US Cases
CDC.gov
Lab confirmed cases as of 12/28/16. Total cases: 4809; 95.5% are travel related.
Zika Infection-Mouse Male Infertility
Govero J et al. Nature. 2016, Oct 31, Epubl
• Mice infected with 2 strains of Zika virus: Fr. Polynesian and Senegalese.
• Dengue virus (a mosquito born flavovirus) infection served as controls.
• Evaluated viral presence in reproductive tissue, hormones and sperm production in all mice
Zika Infection-Mouse Male Infertility
Govero J et al. Nature. 2016, Oct 31, Epubl
• Both strains of Zika virus found in testes of mice, unlike Dengue virus.
• Virus observed in mature sperm as well as in Sertoli cells, spermatogonia and primary spermatocytes.
Results
Zika Infection-Mouse Male Infertility
Govero J et al. Nature. 2016, Oct 31, Epubl
• Zika infected testes looked normal at 1 week.• By week two, atrophy was observed• By week three, testis tissue was destroyed• Although mice cleared the virus, testis atrophy
was not reversible.
Results cont’d
Zika Infection-Mouse Male Infertility
Govero J et al. Nature. 2016, Oct 31, Epubl
• There were corresponding decreases in testosterone and inhibin B levels in Zika infected male mice.
• Sperm counts were also reduced.• Zika mice showed ¼ of normal fertility in mating
studies.
Results cont’d
Zika Infection-Vaccines
CDC.gov
• Flavovirus vaccines currently exist.• Zika virus vaccine constructs give
protective immune responses in mice and nonhuman primates.
• Two DNA Zika virus vaccine constructs are in clinical trials in the US.
Thomas SJ et al. NEJM. 2016; 375: 1212-16