Guillain-Barré syndrome (GBS) is an acute paralyzing illness that is potentially associated with Zika virus infection. Several countries in Latin America have reported increases in GBS cases coinciding with Zika outbreaks. A study in French Polynesia during a 2013-2014 Zika outbreak found that nearly all GBS patients had evidence of recent Zika infection. While the link between Zika and GBS requires more research, the increased GBS incidence in areas with Zika suggests Zika may cause GBS in some cases.

1. 3/9/2016
Zika Virus and
Guillain-Barré Syndrome
Michael Wilson, MD

2. What is Guillain-Barré Syndrome (GBS)?
 Acute monophasic paralyzing illness
 Impaired conduction along peripheral nerves (typically demyelinating)
 Incidence: 1-2 per 100,000 people per year
 Occurs worldwide
 M > F
 All age groups affected (more common with increasing age)
 Mortality is under 5%
 Several subtypes including acute motor axonal neuropathy (AMAN)
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

3. What Causes GBS?
 Typically preceded by an infection 1-8 weeks prior
• Campylobacter jejuni
• Haemophilus influenzae
• Mycoplasma pneumoniae
• Cytomegalovirus
• Epstein-Barr virus
• HIV-1
• Influenza-like illnesses
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

4. What does GBS Look Like?
 (Mostly) symmetric muscle weakness
• Most commonly starts in the legs
• Early arm and facial muscle involvement in ~10%
 Paresthesias in the hands and feet are common
 Pain in the back and extremities is an early feature in 2/3 of patients
 Progressing over days
 Absent or depressed deep tendon reflexes
 10-30% of patients develop severe respiratory weakness
 Dysautonomia
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

5. How do you diagnose GBS?
 Clinical syndrome over typical timeline
 History of preceding infection
 Cerebrospinal fluid studies
• Elevated protein
• Normal white blood cell count
 Electromyography and nerve conduction studies
• Demyelinating polyradiculoneuropathy
 Serum antibodies can be associated with some GBS subtypes
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

6. How Do You Treat GBS?
 Immunotherapy
• Plasma exchange
• Intravenous immunoglobulins
 Supportive care
• Respiratory support
• Autonomic dysfunction
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

7. Zika and GBS in Latin America
 Brazil
• 19% increase in GBS cases nationwide from 2014 to 2015
• Northeastern states reported 121 cases (1/15 – 7/15)
 El Salvador
• 104 GBS cases from 12/1/15-1/30/16 (yearly average: 169 cases)
 Colombia
• 5 week period: 86 cases (weekly average: 5 cases)
 Venezuela
• 252 GBS cases in January 2016 (66 in the state of Zulia)
European Centre for Disease Prevention and Control. Rapid Risk Assessment. Zika virus disease epidemic. ECDC; 2016.
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

8. Zika and GBS in French Polynesia
 Case-control study during Zika outbreak from October 2013 to April 2014
 GBS cases (n=42; 74% men; median age of 42 yo)
• 3-10 patients per year from 2009-2012
 Two control groups:
• Patients with non-febrile illness (n=98) matched for age, sex and residence
• Patients with Zika virus infection (n=70) without neuro symptoms (RT-PCR
confirmed)
Cao-Lormeau VM, Blake A, Mons S, et al. Guillain-Barré Syndrome outbreak associated with Zika virus infection in French Polynesia: a case-control study.
Lancet 2016
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

9. Zika and GBS in French Polynesia
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

10. Zika and GBS in French Polynesia
 Zika IgM Ab positive in 93% of GBS cases vs 17% in non-febrile control group
 Neutralizing Zika Ab present in 100% of GBS patients vs 56% of non-febrile
control group (p<0.0001)
 Median interval between viral syndrome and GBS was 6 days
 Rapid progression to symptom nadir: 6 days
 Nerve conduction studies consistent with AMAN subtype
 38% of patients required intensive care
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

11. Zika and GBS in French Polynesia
 All survived
 3 months after discharge, 57% of patients walked without assistance
 Incidence estimated at 0.24 cases per 1,000 Zika virus infections
• Similar to Campylobacter jejuni incidence
 Dengue serologies similar across all three groups
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency

12. Summary: Zika and GBS
 Increased incidence of GBS coinciding with Zika virus outbreaks in multiple
countries
 Link between Zika virus and GBS is still unclear
 Prospective studies are urgently needed to further define the strength of the
possible association between Zika virus infection and GBS
 Zika also reported in conjunction with meningoencephalitis and myelitis
3/9/2016Preparedness for the Zika Virus: A Public Health Emergency