Member Research and Reports

Member Research and Reports

Economic Burden of Zika Epidemic Quantified by Yale Model

The Zika virus, which continues to grow internationally, has the potential to cause widespread harm not only the health of people in affected areas, but to local economies as well. An epidemic can rack up high costs in health care, as well as lost productivity. In a first-of-its-kind study, a research team led by the Yale School of Public Health have quantified the potential economic impact of the epidemic in the United States under a variety of epidemic severity scenarios.

The team, led by Burnett and Stender Families Professor of Epidemiology, Dr. Alison Galvani, used a novel computational model to forecast the economic impact of the virus across a wide variety of possible scenarios in six U.S. states which are most likely to experience an outbreak: Alabama, Florida, Georgia, Louisiana, Mississippi, and Texas. These states along the Gulf of Mexico were chosen because of their proximity to Latin America, where Zika has had a stronghold, and the favorability of conditions there for the species of mosquitos, which transmit the virus.

The study, published in PLOS Neglected Tropical Diseases, is the first to examine the potential economic cost of Zika in the United States, and contributes valuable data to the ongoing debate regarding resource allocations to address the epidemic. If one out of every 10,000 persons in Florida and Texas were to be infected with Zika virus, the total costs due to Zika associated microcephaly and other central nervous system disorders, as well as Guillan-Barré syndrome were estimated to range from $14 to 106 million and $25 to 193 million, in the two states respectively. The study also reveals the primary determinants of Zika-associated costs, which include health care utilization, Medicaid costs, direct medical costs, and worker productivity loss.

While the attack rates that are being calculating for are of a highly hypothetical nature and unlikely to be constant across an entire state (especially across all 6 states), the calculations can be scaled to the appropriate population sizes that are expected to be at risk, said Galvani, director of the school’s Center for Infectious Diseases Modeling and Analysis (CIDMA)

The results have the potential to help guide policy decisions surrounding Zika preparedness and response. Without knowing which prevention methods might be implemented and how effective they might be, it is difficult, according to the paper, to know exactly how much of the associated costs of Zika might be averted, but the team estimates that assuming one-third of costs could be averted through preventive measures, an attack rate of 1 percent across the six states would justify one billion dollars in investments into prevention and control.

Evaluating the hypothetical, but possible, ways in which a Zika outbreak could occur would be difficult, according to the paper, without a computational model that can factor in the many considerations on how an attack of the disease could strike. The Zika virus can cause a wide array of symptoms of varying severity, including fever, rash, joint pain, conjunctivitis, muscle pain and headache. It is also linked to more serious conditions, including Guillain-Barre Syndrome, and microcephaly as well as other central nervous system disorders in newborns. All of these potential symptoms were among the scenarios tested by the model.

The team also included Associate Research Scientist Dr. Jorge Alfaro-Murillo and Ms. Alyssa Parpia, both of CIDMA, as well as researchers from the Johns Hopkins Bloomberg School of Public Health and the Baylor College of Medicine in Houston.