Mosquito Trails: Ecology, Health, and the Politics of Entanglement by Alex M. Nading (review)

This ethnographic, anthropologic examination of dengue control activities in Ciudad Sandino (Managua metropolitan area, Nicaragua, 2006–9) seeks to demonstrate the importance of local specifics of how “people, pathogens, vectors, and their shared surroundings are always in the process of becoming, together” because “environments do not just cause health problems; rather humans and non-humans incorporate one another’s actions” (p. 202). Nading’s informants included community health workers (brigadistas, who worked as dengue case investigators and vector control officials), garbage collectors, scavengers, scrap metal buyers, Ciudad Sandino residents, physicians, entomologists, and epidemiologists.

The analysis is first concerned with the layout and culture of the place, its relation to garbage as a source of both mosquitoes and income (recycling), and the parasitic relationships between large brokers and scavengers, mosquitoes and people, and humans and the environment. Then Nading stresses the appeals of a well-ordered house and knowledge of the mosquito life cycle; the similarity of public health work with evangelical house-to-house visits and the mosquito’s life (brief visits to the homes’ most intimate spaces); and the gendered condition of dengue control work (women held responsible for prevention activities in the home, and the paradoxical self-identification of single-mother brigadistas with female mosquitoes, which become dangerous, biting humans and laying eggs, only after the males impregnate them and fly away). Finally, the author examines the intricacies of disease surveillance for global and local health, the disappearance of human stories into data points, and the repetitiveness and confluence of viral epidemics and clinical diagnoses.

Nading defines “entanglement” as an analytical framework to examine “the unfolding, often incidental attachments and affinities, antagonisms and animosities that bring people, nonhuman animals, and things into each other’s worlds” (p. 11). Even in strictly biological terms, dengue is quite “entangled.” It is produced by any of four closely related viruses (dengue serotypes 1–4) transmitted by Aedes mosquitoes (mostly Ae. aegypti, also the vector of yellow fever). They breed in containers of relatively clean water associated with human environments, such as flower vases, old tires, cans, and bottles.

Dengue is characterized by sudden onset, fever, headache, muscle and joint pains, loss of appetite, and other symptoms or signs of variable frequency. Each viral serotype provokes immunity only to itself, so residents of endemic areas with multiple serotypes face the lifetime probability of as many episodes of dengue. Repeat infections increase the risk of shock (sudden drop in blood pressure), which overwhelms the body’s control of coagulation and produces difficult-totreat hemorrhages and a fatal outcome. The nonspecific initial symptoms, variable nature of disease progression, and lack of inexpensive, rapid diagnostic tests or specific curative drugs produce a complicated situation for medical management.

The explanations for the behavior of the disease further complicate the story. Dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS) were characterized in Southeast Asia in the late 1950s and early 1960s. A prolonged controversy about the relative power of two factors for severity—viral characteristics versus immune response—was resolved in a consensus that both are important, but immune response is the common underlying trigger. This imposed the goal of a vaccine effective against all serotypes simultaneously, to avoid the chance of repeated infection and severe disease.

At the end of the 1990s, new laboratory techniques raised hopes for a vaccine, so study sites were established to examine dengue in populations that might benefit from immunization (e.g., in Managua, pp. 148–49, 176, 186). In the meantime, control has focused on mosquito abatement through the elimination of breeding sites. The methods developed for individuals and communities to assume responsibility for vector control have shown limited success, and Nading shows many of the obstacles (pp. 64, 90, 98–99, 112, 126, 129–30, 140, 145, 147, 154–59).

Dengue control efforts, as the author makes clear, must consider not only the universal interaction among...