Aug 15th, 2014
Two APK faculty members are being recognized for performing with distinction. Read more here […]
Aug 15th, 2014
Dr. Ashley Smuder, a NIH post-doctoral fellow in the Department of Applied Physiology and Kinesiology, has been promoted to Research Assistant Professor. She will continue her work in Dr. Scott […]
Nov 3rd, 2014
We are excited to announce that Dr. Beth Barton, currently in the Department of Anatomy and Cell Biology at the University of Pennsylvania, has been hired by APK as part […]
September 26, 2016
It is estimated that about 80 percent of Zika infections are asymptomatic or have symptoms so mild that the disease is not detected. This means the number of cases reported by disease surveillance systems in the U.S. and across the world might be only a small fraction of the actual number of infections. In fact, it’s likely we are are underestimating imported cases in the U.S. and even likely some locally spread cases. In this situation, mathematical and computational models that account for mosquito populations, human mobility, infrastructure and other factors that influence the spread of Zika are valuable because they can generate estimates of the full extent of the epidemic. This is what our research group, made up of physicists, biostatisticians and computer scientists, has done for Zika. The Global Epidemic and Mobility Model (GLEAM) can model the spread of Zika through countries and geographical regions. Our model suggests that while more cases of Zika can be expected in the continental U.S., outbreaks will probably be small and are not projected to spread. By contrast, some countries, like Brazil, have already seen widespread outbreaks. How does the model work? Zika is primarily transmitted by Aedes mosquitoes. For a mosquito to transmit Zika to a human, it must first have bitten a human infected with the virus. If enough people infected with Zika travel to a new area with these mosquitoes, the virus could spread in a new geographic region. That means models for Zika transmission need to take factors like mosquito population, human mobility and temperature, among others, into account. So we begin by dividing the population of the Americas into geographical cells of similar size, and grouping these cells into subpopulations centered around major transportation hubs. 7 Our model also incorporates data on the density of the mosquitoes that transmit Zika, Aedes aegypti and Aedes albopictus, within those subpopulations. Mosquitoes need warm weather to thrive, so we include a daily estimated temperature for each subpopulation. That allows us to factor seasonal temperature changes into our simulations. To breed, mosquitoes need standing water, and to spread Zika, they need people to feed on. Areas with standing water, fewer window screens and less air conditioning, which are often lower-income areas, are at greater risk. The model uses detailed data about socioeconomics for each subpopulation, as well as data on the relationship between socioeconomic status and risk of exposure to mosquito-borne disease. Once all of these factors are incorporated into the model, we simulate a Zika outbreak. These simulations are meant to project what will happen next with Zika, so they need to include information about what has already happened. The simulations were calibrated to match data from countries that experienced the epidemic first, like Brazil and Colombia. We started by “introducing” Zika into one of 12 major transportation hubs in Brazil. Each calibration starts with a different time and place where Zika was first introduced into the country, and simulates about 500,000 possible epidemics. From those we select a few thousand that match surveillance data to project the epidemic forward. Randomness is also incorporated into the simulations so that the resulting “epidemics” can reflect the natural variability in how diseases spread. Zika’s spread in the U.S. will be limited Based on current data, our model projects only small outbreaks from mosquito transmission in the continental U.S. that are likely to die out before spreading to new areas. Alabama, Arkansas, Georgia, Louisiana, Mississippi, Oklahoma, South Carolina and Texas are at risk of these small outbreaks. This is because it is warm enough in these states through the summer and fall to sustain mosquito transmission. But the median number of daily cases from local mosquito transmission in these states is projected to be zero. This means that in general we do not expect an outbreak to happen, though small outbreaks are possible. Any outbreaks in these states are expected to end by November or December 2016, consistent with declining temperatures and the end of mosquito season. Florida, on the other hand, may observe sustained transmission between September and November 2016. After calibrating the model with available surveillance data through mid-August, on average, less than 100 symptomatic Zika cases are projected by the second half of September. As many as eight pregnant women could be locally infected in the first trimester, though these women would not give birth until October 2017. In comparison, over 671 pregnant women infected during travel have already been identified in the U.S. as of September 1, 2016. And, as in other states, when mosquito season ends in December, so will Zika transmission from local mosquitoes. Keep in mind, we are just talking about people getting infected with Zika from local mosquitoes. In the U.S. the number of local cases is expected to be small relative to the number of travel-related infections and to affect comparatively few pregnant women. The number of travel-related and local cases that are detected by the Zika surveillance system in the continental U.S. is likely much smaller than the total number of infections. Our model estimates that only 2 percent to 5 percent of travel-related infections are detected by surveillance. And local infections may not be detected for individuals without symptoms. But even taking frequent travel-related infections and low detection rates into account, our models project few local cases in the continental U.S. It’s a different picture for other parts of the Americas. Our models suggest that larger outbreaks occurred or will occur in Brazil, Colombia, Venezuela and Puerto Rico. All have tropical or subtropical climates, have higher densities of the mosquito vectors, and may be at greater risk due to socioeconomic factors. This is a projection, not a prediction Remember, these are projections for what might happen, not predictions of what will happen. No model can perfectly replicate reality. For instance, this model doesn’t account for sexual transmission. We still don’t know how common it is for a person infected with Zika to transmit it during sex. Sexual transmission may proportionally have a larger effect in domestic outbreaks than we realize. This type of detailed modeling is complex, and that makes it difficult to examine what is happening within states, or even within single counties. It will take more time and data to analyze simulations at such local levels. Finally, the model does not include any interventions, such as increased mosquito control. Unless other modes of transmission, such as sexual transmission, turn out to be significant factors, our projection might be considered a worst-case scenario. Model projections like this should be always scrutinized using information about what is happening on the ground. And they need to be recalibrated and refined as new information becomes available. This article originally appeared in The Conversation on Sept. 12, 2016.
September 26, 2016
It might not be surprising news that a night of heavy drinking impacts a person’s short-term memory, but University of Florida researchers have found that older adults’ mental abilities are more affected by heavy drinking than younger adults, and that heavy drinking in youth can have long-lasting effects on memory and learning in old age. Researchers investigated the effects of current heavy alcohol consumption as well as a past history of heavy alcohol use on adults. They found the older a person is, the more significantly heavy drinking affects thinking and memory. They also found a lifetime of past heavy drinking has the same negative impact, even after someone stops drinking. The researchers published their findings online Thursday (Sept. 22) in the journal Alcoholism: Clinical and Experimental Research. “As people get older, their decline of memory is one of their greatest complaints. We found that in those who drink heavily, as they age, they have a greater decline in thinking and memory than their non-drinking or moderate-drinking counterparts,” said Adam Woods, Ph.D., an assistant professor in the UF College of Medicine’s department of aging and geriatric research who led the study. “The real story is less of an age story and more of one of the consequences of heavy drinking in your past. You may think, ‘Well, I’m young, I’ll be fine, my body can take it.’ The reality is our data suggest this may not be the case. If you are drinking heavily, you may experience long-term cognitive consequences throughout life.” Some of these consequences can be difficulty learning new technology, remembering steps to a recipe, taking a medication on a prescribed schedule, and even driving. For the study, researchers recruited 66 participants — 35 women and 31 men between the ages of 35 and 70. The participants met the National Institute on Alcohol Abuse and Alcoholism’s criteria for heavy drinking, which means both men and women drank five or more drinks on the same occasion on five or more days in the past 30 days. The participants, recruited from the Lifespan/Tufts/Brown University Center for AIDs Research, underwent a comprehensive battery of testing to investigate their mental abilities and memory recall. The participants were also compared with non-drinkers and moderate drinkers. The researchers found that heavy drinking in older adults was associated with poorer global cognitive function, learning, memory and motor function. A history of heavy past drinking was associated with poorer function in those same areas as well as in attention. “Learning and memory is so central not only to our ability to function in an everyday environment, but it’s also a subcomponent in almost every element of human cognition,” said Woods, who is also the assistant director of the Center for Cognitive Aging and Memory Clinical Translational Research Program in the Evelyn F. and William L. McKnight Brain Institute at the University of Florida.
September 16, 2016
As the mom of a young child with autism spectrum disorder, Jovon Howard is hesitant to step away even for a few minutes to take a shower or wash the dishes. Her daughter, 6-year-old Jaliyah, is as curious as any child and has figured out how to unlock doors. And because she is primarily nonverbal, Jaliyah won’t respond to being called. “We’ve had a couple of major scares,” her mom said. Now, a new state program aims to help families like Jaliyah’s, providing free, wristwatch-style GPS tracking devices to people who have autism spectrum disorder and are at risk for wandering. The state-funded pilot program, being launched by the Center for Autism and Related Disabilities at the University of Florida and two other centers, will cover the cost of the devices for participants as well as receivers for local sheriff’s offices. In addition to the UF center, centers at Florida Atlantic University and the University of South Florida will provide devices to participants in the Palm Beach and Tampa areas. The devices are being made available through state grants — $100,000 to each of the three centers — as a result of Senate Bill 230, which the Legislature passed this year. The law is aimed at improving personal safety for people with autism spectrum disorder by providing tracking devices that aid in search-and-rescue efforts. Known as Project Leo, the law was passed following the 2014 death of 9-year-old Leo Walker, a boy with autism spectrum disorder who wandered from his North Florida home and drowned in a nearby pond. Under the program, 80 personal transmitters — which can be attached to clothing or worn around the wrist or ankle — will be available at the UF center and distributed to those who meet certain criteria, including risk of wandering and a diagnosis of autism spectrum disorder. “It can save lives,” said Ann-Marie Orlando, Ph.D., a research assistant professor at UF’s Center for Autism and Related Disabilities. “We want children and families to be protected.” The program is geared toward helping families who cannot afford such devices, which are available for purchase online and can be connected to receivers already in use by many sheriff’s offices, including the Alachua County Sheriff’s Office. “Some families can afford them, but others can’t,” Orlando said. “The purpose is to help those who can’t do this on their own.” Greg Valcante, Ph.D., director of UF’s center, wants to get the word out to parents who might be interested in participating in the pilot program. In the Gainesville region, residents of Alachua, Columbia, Suwannee, Hamilton and Baker counties may apply; those interested should contact Ana Vilfort Garces at the Center for Autism and Related Disabilities at 352-273-0581 or firstname.lastname@example.org. UF’s center is obtaining its transmitters from Project Lifesaver International, a Port St. Lucie-based nonprofit that sells electronics intended for people with cognitive disorders. According to Project Lifesaver, most people who wander are found within a few miles of home, and the use of tracking devices has cut search times from hours or days to minutes. The three Florida centers will report back on the results of the pilot project by December 2017 and make recommendations to the governor and Legislature. For Jovon Howard of Gainesville, word of the new program is great news. Her family had briefly used a tracking device with Jaliyah — a device that provided status updates to their smartphones — but it became too costly. “Her wanting to get out is her natural curiosity as a child,” Howard said. “The problem is she doesn’t have a sense of danger. She’s just doing what kids naturally want to do.”