By Dr. Luz Mendoza
Tropical disease research is the scientific study of infections that thrive in warm, humid climates and disproportionately affect low- and middle-income countries. In Peru, that means dengue, leishmaniasis, Chagas disease, leptospirosis, and soil-transmitted helminths. Adjacent concepts include neglected tropical diseases (NTDs), vector-borne transmission, zoonotic spillover, and the social determinants of infection. For Spanish-speaking students and professionals working between molecular biology and field epidemiology, the funding gap is not an abstract policy problem. It shapes which questions get asked, which samples get sequenced, and which communities receive timely diagnosis. This article explains how tropical disease research gets underfunded, why the usual explanations are incomplete, and what the evidence actually shows about the consequences for Peruvian ecosystems and public health.
The Funding Gap in Numbers
Global health funding is heavily skewed toward diseases that affect high-income countries. According to the World Health Organization, more than one billion people are affected by neglected tropical diseases, yet NTD programs receive a small fraction of global health research investment. A 2022 analysis by Policy Cures Research found that basic research and product development for neglected diseases received about $4.1 billion in 2021, while HIV, tuberculosis, and malaria together received more than three times that amount. Dengue, a disease that causes major outbreaks in northern Peru, receives less than 10% of the funding allocated to malaria, even though its geographic range is expanding rapidly.
In Peru, the gap is visible at the institutional level. Public universities such as Universidad Nacional Mayor de San Marcos and Universidad Peruana Cayetano Heredia maintain strong tropical medicine programs, but their laboratories often depend on short-term international grants. When a grant ends, equipment maintenance slows, reagent stocks shrink, and trained personnel move to better-funded projects. This is not a failure of individual researchers. It is a structural feature of how tropical disease science is financed.
Why the Market Fails Tropical Diseases
The standard explanation is that tropical diseases affect poor people, so there is no profitable market for drugs, vaccines, or diagnostics. That explanation is true but incomplete. The funding problem also comes from how research priorities are set, how grant cycles work, and how scientific prestige is distributed.
The Commercial Disincentive
Pharmaceutical companies invest where they can recover costs. A new antihypertensive drug can generate billions of dollars in revenue. A new treatment for chronic Chagas cardiomyopathy, which affects mostly rural populations in Latin America, offers little commercial return. This is why benznidazole and nifurtimox, the two main drugs for Chagas disease, were developed more than 50 years ago and have known toxicity problems. The market has not produced a better option because the market has no incentive to do so.
This is similar to what happens in a small Peruvian market town. If only a few families can pay for a product, no vendor will stock it, even if those families need it urgently. The difference is that in global health, the families are entire regions, and the vendors are multinational corporations with research budgets larger than some national economies.
The Prestige Problem
Scientific careers are built on publications in high-impact journals. Those journals tend to favor research on diseases with broad international readership. A molecular study of a newly discovered coronavirus variant will attract more attention than a careful field study of Bartonella bacilliformis in Andean valleys. The coronavirus study may be important, but the Bartonella study may be equally important for the communities affected. The difference is not scientific merit. It is perceived relevance.
Young researchers in Peru see this clearly. A talented molecular biologist can choose between a well-funded project on cancer biomarkers, with international collaborators and stable reagents, or a poorly funded project on Carrion’s disease, with difficult field conditions and uncertain publication prospects. Many choose the first option. That is a rational career decision. But it means tropical disease expertise is slowly leaking out of the system.
The Grant Cycle Trap
Most research grants last two to five years. Tropical disease research often requires longer time horizons. Vector ecology studies need multiple seasons to capture climate variability. Community-based interventions need time to build trust. Longitudinal cohort studies need years of follow-up. When funding cycles are short, researchers are pushed toward quick, publishable results rather than durable, field-based knowledge.
This is like trying to understand ceviche preparation by watching only the first minute of the process. You see the fish being cut, but you miss the acid denaturation, the timing, the balance of ají and limón. The result is a partial picture that misses the mechanism. In tropical disease research, short funding cycles produce partial pictures that miss transmission dynamics, ecological interactions, and the slow work of building laboratory capacity.
What Gets Left Out
Underfunding does not simply mean less research. It means a specific kind of research gets left out. The work that disappears first is the work that is hardest to fund through competitive grants: long-term surveillance, basic taxonomy of vectors and reservoirs, maintenance of strain collections, and training of field technicians.
Surveillance Gaps
Peru has a diverse geography that creates distinct disease ecologies. The Amazon basin, the Andean highlands, and the coastal desert each support different vectors and pathogens. Effective surveillance requires continuous sampling across these regions. But continuous sampling is expensive and unglamorous. It does not produce a single dramatic discovery. It produces a slow accumulation of data that becomes valuable only when an outbreak occurs.
When surveillance is underfunded, outbreaks are detected late. The 2017 dengue epidemic in Peru, which caused more than 68,000 cases, exposed weaknesses in early warning systems. By the time the outbreak was recognized, the virus had already spread through multiple districts. Better surveillance might not have prevented the epidemic, but it could have shortened the response time and reduced severe cases.
Vector Biology and Ecology
Controlling vector-borne diseases requires understanding the vector. For example, the sandfly species that transmit leishmaniasis in Peru have different behaviors depending on altitude, forest cover, and human settlement patterns. Some species bite indoors; others bite outdoors. Some are active at dusk; others at night. These details matter for designing control programs. But detailed vector ecology studies are rarely funded because they are site-specific and do not generalize easily.
This is a loss for science and for public health. Without basic ecological data, control programs rely on generic strategies that may not fit local conditions. Insecticide-treated bed nets work well for malaria vectors that bite indoors at night. They work less well for sandflies that bite outdoors at dusk. The difference is not academic. It determines whether a control program works or fails.
Local Laboratory Capacity
Molecular biology requires infrastructure: reliable electricity, cold storage, PCR machines, sequencing equipment, and trained personnel. In many Peruvian regions, this infrastructure is concentrated in Lima. Field sites in Iquitos, Pucallpa, or Cajamarca may have basic laboratories but lack the capacity for advanced molecular diagnostics. When samples must be shipped to Lima or abroad, delays increase, sample quality degrades, and local researchers lose the opportunity to build skills.
Funding agencies sometimes support equipment purchases but not the long-term costs of maintenance and training. A PCR machine without reagents is like a kitchen without ingredients. The equipment is there, but the work cannot happen. Sustainable capacity requires funding for salaries, reagents, service contracts, and continuing education. That kind of funding is rare.
The Peruvian Context
Peru is a particularly instructive case because it combines high biodiversity, diverse climates, and a strong tradition of tropical medicine research. The country has produced important contributions to the understanding of Bartonellosis, leishmaniasis, and HTLV-1. But the current funding environment makes it difficult to sustain that tradition.
One example is the work on Carrion’s disease, caused by Bartonella bacilliformis and transmitted by sandflies in Andean valleys. The disease has been known since the 19th century, but many basic questions remain unanswered. Why do some patients develop severe anemia while others have mild symptoms? What is the role of asymptomatic carriers in transmission? How does climate change affect the distribution of the sandfly vector? These questions require long-term investment in field sites and laboratory capacity. Current funding levels do not support that investment.
Another example is the rise of dengue in urban areas. Dengue was once considered a disease of the Amazon basin. Now it is established in Piura, Tumbes, and other coastal cities. The expansion is driven by urbanization, water storage practices, and climate variability. Understanding this expansion requires collaboration between entomologists, epidemiologists, and social scientists. But interdisciplinary research is hard to fund because it does not fit neatly into single-disease categories.
What the Evidence Says About Solutions
The funding gap is not inevitable. Several mechanisms have been proposed to address it, and some have shown promise. But each has limitations, and none is a complete solution.
Product Development Partnerships
Product development partnerships (PDPs) bring together public, private, and philanthropic funders to develop drugs, vaccines, and diagnostics for neglected diseases. Examples include the Drugs for Neglected Diseases initiative (DNDi) and the Medicines for Malaria Venture. These partnerships have produced new treatments for sleeping sickness, malaria, and leishmaniasis. They work by sharing risk and removing the profit motive from the equation.
However, PDPs focus on product development, not on basic research or field ecology. They are necessary but not sufficient. A new drug for leishmaniasis does not solve the problem of underfunded vector surveillance. The two types of research are complementary, but they compete for the same limited pool of funding.
Research Capacity Strengthening
Some funders, including the Wellcome Trust and the Fogarty International Center, support programs that build research capacity in low- and middle-income countries. These programs fund training, mentorship, and institutional partnerships. They have helped create a generation of Peruvian researchers with skills in genomics, bioinformatics, and field epidemiology.
The limitation is that capacity strengthening is often tied to specific projects. When the project ends, the capacity may not be sustained. A more durable approach would fund core laboratory operations, not just project-specific activities. That requires a shift in how funders think about return on investment.
Regional Collaboration
Peru shares disease ecologies with neighboring countries. Leishmaniasis, dengue, and Chagas disease do not respect borders. Regional collaboration can reduce duplication and share costs. For example, a reference laboratory in Lima could serve as a hub for molecular diagnostics for Bolivia and Ecuador, while field sites in those countries provide ecological data that Peru lacks.
Regional collaboration is politically difficult. Countries have different regulatory systems, different research priorities, and different levels of institutional capacity. But the scientific case is strong. Diseases that cross borders require research networks that cross borders.
What Students and Professionals Can Do
The funding gap can feel like a distant policy problem. But for students and early-career researchers, it has practical implications. The choices made now shape the future of tropical disease science in Peru.
First, learn the funding landscape. Understand which agencies fund tropical disease research, what they prioritize, and how to write competitive proposals. This is not cynical careerism. It is a necessary skill for doing the work.
Second, build collaborations early. Tropical disease research is rarely a solo endeavor. It requires partnerships between molecular biologists, field epidemiologists, entomologists, and community health workers. Those partnerships take time to build and maintain.
Third, document what is missing. When a surveillance program is cut, when a laboratory loses its reagent budget, when a field site closes, that loss should be recorded. The evidence base for advocacy depends on knowing what was lost and why.
Frequently Asked Questions
Why are tropical diseases called neglected?
The term “neglected tropical diseases” refers to a group of infections that affect mainly poor populations in tropical and subtropical regions and receive less attention and funding than diseases such as HIV, tuberculosis, and malaria. The neglect is not biological; it is political and economic. These diseases cause significant disability and death, but they do not generate commercial markets for new products.
How does underfunding affect disease surveillance in Peru?
Underfunding reduces the frequency and geographic coverage of surveillance. When surveillance is weak, outbreaks are detected later, and public health responses are slower. In Peru, this has been observed with dengue epidemics in coastal cities and with leishmaniasis in Amazonian communities. Weak surveillance also means that changes in vector distribution, such as the expansion of Aedes aegypti into new areas, are noticed only after cases appear.
What is the difference between funding for basic research and funding for product development?
Basic research asks fundamental questions about how pathogens, vectors, and hosts interact. Product development aims to create specific tools such as drugs, vaccines, or diagnostics. Both are needed, but they are funded differently. Product development partnerships have attracted significant philanthropic investment because they produce tangible results. Basic research, especially field ecology and long-term surveillance, is harder to fund because its results are less immediate and less visible.
Can Peru build sustainable tropical disease research capacity without international funding?
In the current economic context, it is unlikely. Peru’s public research budget is small relative to the burden of tropical diseases. International funding will remain important for the foreseeable future. The goal should be to use international funding to build durable local capacity, not to create permanent dependence. That means investing in training, equipment maintenance, and institutional partnerships that outlast individual grants.
A Note on Uncertainty
The evidence on tropical disease research funding is incomplete. Funding data are often aggregated across diseases and countries, making it difficult to track specific investments in Peruvian field sites. Some funding flows through channels that are not publicly reported. The numbers cited here should be understood as estimates, not precise measurements. The overall pattern, however, is consistent across multiple sources: tropical diseases receive less research funding than their disease burden would justify, and the gap is especially wide for basic research and field ecology.
What Comes Next
This article is the first in a series on how tropical disease research is organized, funded, and practiced in Peru. Future articles will examine specific diseases, including leishmaniasis and Carrion’s disease, and specific funding mechanisms, including PDPs and capacity-strengthening programs. The goal is to build a durable resource for students and professionals who want to understand not just the science of tropical diseases, but the systems that shape that science.
If you have questions about a specific funding program or a particular disease, send them to the blog. Reader questions help shape the editorial calendar and ensure that the content addresses real needs in the Peruvian research community.
