<--GAT-->
Clinical Topics

Zika Infection Had More Serious Effects in Older Veterans With Comorbidities

by Brenda Mooney

August 19, 2018

WASHINGTON—Zika virus infection had affected more than a half-million people in the Western Hemisphere by the end of 2016. Among those were more than 700 VA patients with confirmed or presumed possible infection.

Much of the concern was about the effects on unborn fetuses or young women seeking to become pregnant, with the assumption that ZIKV infection’s effects were generally mild in everyone else. The new article, published in PLOS Neglected Tropical Diseases, raised questions, however, about the danger of Zika in an older population with significant co-morbidities.1

To help add to the understanding of which patients are most at risk of severe disease from ZIKV infection, researchers from Public Health Surveillance & Research at the VA described risk factors for hospitalizations and neurologic complications among veterans.

The study found that older veterans with multiple comorbidities, as well as those presenting with neurologic symptoms, were more likely to be hospitalized. Interestingly, patients presenting with rashes were less likely to be hospitalized, according to the report.

In addition, researchers report that patients who were hospitalized or had a prior history of cerebrovascular disease or dementia were more likely to develop neurologic complications.

“Better understanding of those patients most at risk for severe disease can help providers when evaluating and treating patients with ZIKV infection,” study authors wrote.

“Hospitalization and deaths are reported to be uncommon in ZIKV infection,” researchers added. “During the 2007 ZIKV outbreak in Micronesia, among 49 confirmed and 59 probable cases, patients presented with typical symptoms described here, but none were hospitalized, and none died. Although patients in that study were on average >10 years younger, fewer had comorbidities than U.S. veterans. In Brazil, among 119 ZIKV confirmed patients, only one hospitalization and no deaths were reported]. Hospitalizations and death (<1%) were noted in Puerto Rico from November 2015-July 2016. In our veteran population, 3% died after a ZIKV diagnosis, and 13% were hospitalized, which is higher than other ZIKV studies and may be related to veterans increased comorbidities.

An outbreak of ZIKV, a flavivirus transmitted primarily by Aedes mosquitos, occurred in 2015 and 2016, affecting hundreds of thousands of people, including more than 5,000 cases in the continental United States and more than 36,000 in Puerto Rico and the Virgin Islands. Because VHA has healthcare facilities throughout the United States and its territories, it was an ideal location to perform ongoing surveillance for emerging pathogens, the study suggested.

For the recent study, researchers conducted a case series study of all ZIKV cases in VHA hospitals in 2015 and 2016, analyzing patient characteristics and clinical outcomes of 736 ZIKV positive patients out of the 1,538 patients who were tested for ZIKV during that time.

Over, 736 (48%) of the patients tested positive for ZIKV. Most, 89%, were male, and the great majority, 93%, were treated by the VA Caribbean Healthcare System. The remaining 7% of patients were diagnosed at 24 other VHA medical centers.

Documented Travel

Documented travel for those diagnosed in the continental United States included non-Puerto Rico Caribbean (18), Puerto Rico (16), Central America (9), South America (2), Indonesia (1) and Senegal (1), while six patients had exposure only in Florida.

Mean age of all patients was 58.8 years (range 20-99), although patients from the VA Caribbean Healthcare System compared to returning travelers with ZIKV infection were older (mean age 60 vs. 47).

Hospitalization was necessary for 13% of the patients, and 3% died after their ZIKV infection. Results indicated that hospitalization was associated with:

  • Increased Charlson co-morbidity index (adjusted odds ratio [OR] 1.2; 95% confidence interval [CI], 1.1-1.3);
  • Underlying connective tissue disease (OR, 29.5; CI, 3.6-244.7);
  • Congestive heart failure (OR, 6; CI, 2-18.5);
  • Dementia (OR, 3.6; CI, 1.1-11.2);
  • Neurologic symptom presentation (OR, 3.9; CI, 1.7-9.2);
  • Leukocytosis (OR, 11.8; CI, 4.5-31);
  • Thrombocytopenia (OR, 7.8; CI, 3.3-18.6);and
  • Acute kidney injury (OR, 28.9; CI, 5.8-145.1), or using glucocorticoids within 30 days of testing (OR, 13.3; CI 1.3–133).

Patients presenting with rash were less likely to be hospitalized (OR, 0.29; CI, 0.13–0.66), however.

Researchers also reported that risk for neurologic complications increased with hospitalization (OR, 5.9; CI 2.9-12.2), cerebrovascular disease (OR 4.9; CI 1.7-14.4), and dementia (OR 2.8; CI 1.2-6.6).

“ZIKV has been documented to have congenital as well as neurologic complications,” the study authors wrote. “Forty-six patients in our cohort were also noted to have neurologic complications after ZIKV infection. While these neurologic complications are quite broad, they identify potential complications post-ZIKV infection. Prior history of CVD and dementia as well as being hospitalized with ZIKV increased risk of neurologic complication. It was difficult to confirm whether these other neurologic complications were the result of ZIKV infection. Since neonatal and pediatric care was not provided by VA, the status of the infants exposed to ZIKV is unknown.”

1. Schirmer PL, Wendelboe A, Lucero-Obusan CA, Ryono RA, et. Al. Zika virus infection in the Veterans Health Administration (VHA), 2015-2016. PLOS Neglected Tropical Diseases, 2018; 12 (5): e0006416 DOI: 10.1371/journal.pntd.0006416


Comments are closed here.


Related Articles

VAMCs Usually as Good or Better Than Private Hospitals in Same Communities

Veterans are being given more options for obtaining care outside of the VA healthcare system. The question raised in new research is whether doing so improves care.

Report Could Add 23 Presumptive Conditions for Gulf War Veterans

A new report from the National Academies of Sciences, Engineering, and Medicine found that sufficient evidence supported an association between exposure to seven factors and detrimental reproductive effects in men or women who served in the Gulf War or developmental effects in their children.


U.S. Medicine Recommends


More From infectious disease

Infectious Disease

DHA Releases Interim Guidance for HIV Pre-Exposure Prophylaxis

The Defense Health Agency (DHA) has released interim guidance designed to optimize clinical use of human immunodeficiency virus (HIV) pre-exposure prophylaxis and reduce variability in access to prophylactic medication.

Infectious Disease

With Advancing Age, Veterans with HIV Face Novel Challenges

Thirty years ago, veterans with human immunodeficiency virus and their physicians focused on survival.

Infectious Disease

Could Bilirubin Measurements Predict, Prevent CV Events in HIV Patients?

For most people, mention of bilirubin, which is formed after the breakdown of red blood cells and is eliminated by the liver, elicits thoughts of jaundice—which occurs when the compound is too high.

Infectious Disease

VA Pilots Automated Nationwide MDRO Alert System

The VA has successfully piloted a nationwide system to alert VA facilities when patients are admitted with a history of infection with two challenging multidrug resistant organisms (MDROs).

Infectious Disease

Protocols to Prevent Pathogen Transmission Often Violated in Hospitals

Precautionary practices to prevent infectious agent transmission in hospitals often fail, according to a study looking at 325 patient rooms, including some at a VAMC.

Subscribe to U.S. Medicine Print Magazine

U.S. Medicine is mailed free each month to physicians, pharmacists, nurse practitioners, physician assistants and administrators working for Veterans Affairs, Department of Defense and U.S. Public Health Service.

Subscribe Now

Receive Our Email Newsletter

Stay informed about federal medical news, clinical updates and reports on government topics for the federal healthcare professional.

Sign Up