"Death" - what is it, definition of the term
«Death» is the irreversible cessation of all vital biological processes that sustain an organism, marked by the permanent loss of consciousness, respiration, and circulatory activity; it denotes the final stage of the life cycle after which no metabolic or neurological function can be detected.
Detailed information
Mortality linked to arthropod vectors remains a significant public health concern. These organisms transmit pathogens that can lead to severe physiological disruption and, in many cases, fatal outcomes.
Ticks act as carriers for a range of pathogens, including bacteria of the Borrelia genus, viruses such as the tick‑borne encephalitis virus, and protozoa like Babesia. Infection can provoke neurological impairment, renal failure, or hemorrhagic complications. Reported case‑fatality ratios for tick‑borne diseases vary widely, with some viral encephalitides reaching mortality rates above 20 %.
Bugs, encompassing various hematophagous insects, serve as vectors for diseases such as Chagas disease (transmitted by triatomine bugs) and leishmaniasis (carried by sandflies). Chronic infection with Trypanosoma cruzi may culminate in cardiac failure, while visceral leishmaniasis can cause multi‑organ dysfunction. Mortality statistics for these conditions often exceed 10 % in untreated populations.
Lice, particularly body and head lice, are associated with the spread of bacterial infections like epidemic typhus (Rickettsia prowazekii) and trench fever (Bartonella quintana). Typhus outbreaks historically produced mortality rates approaching 30 % in vulnerable groups, especially when secondary complications such as pneumonia develop.
Fleas transmit pathogens including Yersinia pestis, the bacterium responsible for plague, and Rickettsia typhi, the agent of murine typhus. Plague, when untreated, exhibits a case‑fatality rate of 30–60 % for the bubonic form and up to 90 % for the pneumonic variant. Murine typhus generally presents a lower mortality, yet severe cases can still result in death.
Preventive measures focus on vector control and personal protection:
- Regular inspection and removal of ectoparasites from hosts.
- Use of insecticide‑treated clothing and bed nets.
- Environmental sanitation to reduce breeding sites.
- Prompt diagnosis and antimicrobial therapy for vector‑borne infections.
Effective implementation of these strategies reduces the likelihood of severe disease progression and associated mortality.