IMPACTS Team Continues to Combat Life-Threatening Arthropod-Borne Infections in Belize
By Chris J. Bahnsen • October 23, 2018
Now in its second year of a five-year initiative to better understand and detect arboviruses in Belize, the IMPACTS project has expanded its focus to include tick-borne infections in addition to mosquito-borne diseases, like Zika and dengue. IMPACTS (which stands for Integrated Mayo Clinic Program for Arbovirus Community health education Training and Surveillance) is a four-tiered project that is a joint effort with Mayo Clinic, the University of Notre Dame’s Eck Institute for Global Health, and the Belize Ministry of Health.
“Unlike a lot of the mosquito-borne diseases, many tick-borne illnesses are treatable,” says Elitza Theel, Ph.D., microbiologist and co-leader on the project who directs Mayo’s Infectious Disease Serology Laboratory (IDSL) and co-directs the Vector-Borne Diseases Service Line. The IDSL has been testing serum from asymptomatic and symptomatic Belizeans throughout the country to identify these diseases. “So far, we’ve seen evidence of infection with Anaplasma, Babesia, as well as with the Rickettsia species, which are all tick-borne bacterial infections able to be treated with antibiotics. So that’s why we’ve added tick pathogens to our focus.”
As it stands, Belizean health providers often have to outsource human samples from patients with suspected arboviruses to a lab based in Trinidad. Test results can take more than two weeks, by which time, the patient has either recovered from the illness, gotten very sick, or even died. To help reduce outsourcing, IDSL is leading Tier 1 of the project, which focuses on training Belizean laboratorians in diagnostic testing for these infectious agents.
“The goal of Tier 1 is to expand in-country laboratory-testing capacity and quality-assurance practices in Belize,” says John W. Wilson, M.D., with Mayo’s Department of Infectious Diseases, who co-leads the project with Dr. Theel. “And also to expand the country’s diagnostic test menu so providers don’t have to outsource, which besides being quite expensive, puts patients at risk.”
To that end, Mayo has been holding workshops in Belize to help teach providers to do testing in-house. Tier 1 also includes an exchange program that brings Belizean laboratorians to IDSL for further training and to observe how Mayo’s clinical laboratories operate. Thus far, three technologists have been trained to perform PCR testing on serum samples for Zika, dengue, and chikungunya viruses.
“This has been the first exposure that Belizean lab technologists have had to PCR testing for these mosquito-borne infections,” says Dr. Theel. “Now that they’ve been trained, we’re planning to maintain their proficiency by sending them blinded samples, previously characterized as positive or negative for these viruses, until they can purchase the PCR kits themselves and implement testing on patients in-house, hopefully in 2019. So we’ve achieved our first goal, which was to train them to do PCR testing, and that’s been really fulfilling on both sides.”
She adds, “Mayo Clinic is a very teamwork-oriented organization, and I want to mention that this training would not have been possible without the dedicated efforts of multiple development technologists and quality specialists in our Division of Clinical Microbiology, including Dane Granger, Teri Ross, and Lynne Sloan.”
The IMPACTS team hopes to expand Belize’s PCR-testing capabilities to other infectious diseases, including endemic tick-borne agents, in the future.
High Incidence of Rocky Mountain Spotted Fever
Tier 2 involves human surveillance testing (via blood donor samples) to acquire data on current or prior mosquito- and tick-borne infections “to understand the prevalence of these vector-borne infections throughout Belize,” says Dr. Wilson.
After testing more than 800 serum samples, IDSL has identified Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever (RMSF), as a rather widespread pathogen in Belize.
“So far, approximately 23% of the human population that we tested in Belize was seropositive for antibodies to R. rickettsii,” says Dr. Theel. “But when we looked at just the southern district of Belize, 35% of residents in that area were seropositive for this infection. And we know that this infectious agent is transmitted through ticks.”
This is particularly concerning when one considers that, if left untreated, the disease can be “rapidly fatal.” Conversely, if treated in time, the infection is very responsive to the antibiotic doxycycline. Even so, Belizean health providers do not currently consider RMSF as a possible cause of patient symptoms and, thus, do not treat for it.
“We’re working with the Ministry of Health and Central Medical Laboratory to collect serum from patients who present with symptoms of RMSF and other diseases,” says Dr. Theel. “We want providers to start thinking about the possibility of tick-borne infections, which can then be treated appropriately with antibiotics.”
Collecting Ticks In-Country
On a recent trip to Belize, Notre Dame students in master's programs, under the expertise of entomologists John Grieco, Ph.D., and Nicole Achee, Ph.D., co-leaders of the initiative from the Eck Institute, conducted “tick drags.” This is a process by which, using a wooden dowel with a piece of white flannel cloth hanging from it, the cloth is dragged over vegetation in hopes of attracting “questing” ticks that climb to the top of grass stalks and reach out their legs. Once in questing position, a tick patiently waits to attach to a passing animal, and humans do just nicely. Ticks were also collected from domestic dogs—pets of villagers who live in traditional, open-style Mayan huts in the middle of the jungle—that are bringing these parasitic arachnids (possibly infected) back into households.
“We collected a lot of ticks from the tick drag—hundreds of little nymph-stage ticks,” says Dr. Theel. “And maybe 25 ticks from the 10 or 15 dogs that we screened.”
Tick and mosquito collection is part of Tier 3’s overall focus. Once captured, these arachnids are tested to see what vector-borne diseases they may carry.
“Tier 3 is where Notre Dame’s medical entomologist expertise fits in so well,” says Dr. Wilson. “They capture mosquitoes and ticks from different parts of the country and perform molecular testing on the insects for the presence of select arboviruses and bacterial infections, like Rickettsia, to basically understand the carriage incidence of these insects.”
Eventually, Tiers 2 and 3 will be combined to identify hot spots, or “clusters,” throughout the country—areas where human incidence of vector-borne infections are overlapping a prevalence of mosquitoes and/or ticks. Such hot spots will then be geo-mapped to help enhance public health and provider education, which is the purpose of Tier 4 of the project.
Arming Health Providers with Knowledge
Tier 4 has two levels. The first level is to deliver knowledge to health providers about what vector-borne diseases are circulating in Belize.
“Tier 4 is predicated on Dr. Theel’s work on human epidemiology surveillance data (Tier 2) and Notre Dame’s work with vector borne-disease carriage rates and geo-mapping (Tier 3),” says Dr. Wilson. “We need to know what the disease prevalence of these vector-borne diseases is throughout Belize so that we can really inform health providers and the Ministry of Health on what the common infections are, and what to test for, based on clinical presentation, for example, a rash, fever, body aches, etc.”
For mosquito-borne diseases, much of the provider education focuses on preventive strategies, such as pregnancy discussions pertaining to Zika virus and the clinical symptoms for chikungunya and dengue.
So far, IDSL data is showing more of a mosquito-virus prevalence in northern Belize as compared to the south, which is revealing more tick-borne infections.
Public Health Education
The second level of Tier 4 is public health education.
“We want to give communities that serve as hot spots for these arboviral infections a fundamental understanding of what these infections are so that preventive strategies can take place,” says Dr. Wilson. “We’ve worked in a similar capacity with our Mayo Department of Education, where we’ve looked at various strategies such as patient information pamphlets, reading material, and so forth, and we’ve really found that videography-based teaching can be a helpful and powerful tool for patient and community education.”
Part of the reason for this is that visual tools do not have to rely on a medical literacy baseline. Meaning that, in a highly rural community, where basic medical knowledge or a fundamental understanding of diseases is minimal, a pamphlet may be off-putting, or more difficult to assimilate, depending on the degree of literacy in a household. This is where video-based education can be much more effective.
Hence, the IMPACTS team is supplying the Belize Ministry of Health with mobile tablets, uploaded with specific educational video and audio material on arboviral infections, strategies on how not to attract mosquitoes in and around a house, and precautions related to ticks. The tablets are given to outreach workers who visit rural communities and work with families.
On his trip to Belize last June, Dr. Wilson observed how these outreach workers interacted with families, using the mobile tablet tools—to show, for example, visuals on what mosquitoes look like and how common vector-borne infections present certain symptoms.
“One of the things I really like about how this is rolling out is that the information is being delivered by Belizean outreach workers who actually live in these communities,” says Dr. Wilson. “The community members know these outreach individuals who are sponsored through the Ministry of Health. They’re recognized, they’re respected and trusted, and they integrate well with the community, so it allows for a much more comfortable delivery of health-based educational material, rather than having it delivered by an outsider who doesn’t know the culture and might struggle with the language.”
Dr. Wilson was pleased by what he saw on the trip. “With some training and direction, the workers understood, very quickly, how to use the video, photo, and podcast tools in these tablets,” he says.
Given the very positive results of the initial training/observational sessions, the team will now further refine the educational content and compose additional material—including a script for outreach workers to draw on—and download them into the tablets. Formal training sessions will then be implemented in Belize over the next few months. The new material will also include simple questionnaires to get some baseline information on how aware these communities are of mosquito propagation, tick infections, and the like.
“The questionnaire information will help keep us pointed in the right direction, regarding the educational content,” says Dr. Wilson. “It also provides a metric that we can follow up on to assess if families are retaining the educational material and, ultimately, if it’s resulting in behavioral changes.”
Helping Laboratory Equipment Last Longer
Each tier moves forward at its own speed, which was the intent of the IMPACTS team. And, as the project’s second year unwinds, a fifth tier has been developed through Mayo’s Division of Bioengineering. Tier 5 is focused on medical equipment maintenance and repair; Dr. Wilson describes it as a “medical equipment sustainability initiative.” To implement it, a number of bioengineering graduate students from Mayo have been working with the Ministry of Health and University of Belize to identify the equipment that is most commonly used and has a history of maintenance problems.
“It’s so hot and humid in Belize that the microscopes get overgrown with fungus on the lenses, among other problems, which really shortens the shelf life,” says Dr. Wilson. “And so the team is not only focusing on how to clean a microscope, but also how to keep the microscope stored in a more arid setting—for example, storing it in a plastic bag with a desiccant present to keep the humidity low and increase that shelf life.”
Similar strategies are being implemented with other common equipment, like autopipettes, to keep them functional and working properly.
A Prototype Project for Other Latin American Counties
The IMPACTS project has already proven successful enough to attract interest from other countries—including Mexico, Guatemala, and Trinidad—that also want to improve their laboratory capacity training and mitigate the spread of vector-borne diseases.
“We’re very happy about this widening interest because these diseases don’t see country boundaries and certainly continue to spread,” says Dr. Wilson. “So, if we can take a regional approach in this regard, it will give us a much better understanding of not only the prevalence of these diseases, but also how they change and how environmental factors propagate certain vector-borne infections. Working with other countries will also allow us to really enhance public and provider awareness of what diseases are common in different parts of Central America and Latin America.”
Chris J. Bahnsen
Chris J. Bahnsen covers emerging research and discovery for Mayo Clinic Laboratories. His writing has also appeared in The New York Times, Los Angeles Times, and Smithsonian Air & Space. He divides his time between Southern California and Northwest Ohio.